/* roulang page: index */
/* ============ 设计变量 ============ */
:root {
  --bg-primary: #0A1120;
  --bg-secondary: #0F1A2E;
  --brand-primary: #2E7CF6;
  --brand-light: #38BDF8;
  --accent: #2DD4A0;
  --warning: #F5B056;
  --error: #F87171;
  --text-primary: #E7EDF7;
  --text-secondary: #94A3BC;
  --text-muted: #5D6F88;
  --border-color: rgba(255,255,255,0.08);
  --border-light: rgba(255,255,255,0.12);
  --card-bg: rgba(255,255,255,0.03);
  --glass-highlight: rgba(255,255,255,0.06);
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 12px;
  --shadow-card: 0 4px 24px rgba(0,0,0,0.30);
  --shadow-hover: 0 12px 40px rgba(0,0,0,0.45);
  --shadow-glow: 0 0 20px rgba(45,212,170,0.15);
  --container-width: 1200px;
  --font-sans: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
}

/* ============ Reset & Base ============ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 16px;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; transition: color 0.3s ease, border-color 0.3s ease, background 0.3s ease; }
a:hover { color: var(--brand-light); }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input { font-family: inherit; }
ul, ol { list-style: none; }
h1, h2, h3, h4, h5 { font-weight: 700; letter-spacing: 0.02em; line-height: 1.3; }

/* ============ 背景光晕 ============ */
body::before {
  content: "";
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background:
    radial-gradient(circle at 15% 10%, rgba(46,124,246,0.18) 0%, transparent 55%),
    radial-gradient(circle at 85% 90%, rgba(45,212,170,0.10) 0%, transparent 45%);
  pointer-events: none;
  z-index: -1;
}

/* ============ 容器 ============ */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ============ 顶部信息条 ============ */
.top-bar {
  background: #060B14;
  height: 34px;
  display: flex;
  align-items: center;
  font-size: 13px;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-color);
  position: relative;
  z-index: 100;
}
.top-bar .container { display: flex; align-items: center; justify-content: space-between; width: 100%; }
.top-bar .top-domain { color: var(--text-secondary); font-weight: 500; }
.top-bar .top-msg { text-align: center; flex: 1; }
.top-bar .top-msg span { color: var(--text-secondary); }
.top-bar .top-msg .dot { color: var(--accent); }
.top-bar .top-action a { color: var(--text-secondary); border-bottom: 1px solid transparent; padding-bottom: 2px; }
.top-bar .top-action a:hover { color: var(--brand-light); border-bottom-color: var(--brand-light); }

/* ============ 导航栏 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 99;
  height: 72px;
  background: rgba(10, 17, 32, 0.82);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border-color);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.brand { display: flex; align-items: center; gap: 10px; }
.brand .logo-mark {
  width: 36px; height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--brand-primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 16px rgba(46,124,246,0.35);
  flex-shrink: 0;
}
.brand .logo-mark svg { width: 20px; height: 20px; stroke: #fff; }
.brand .logo-text {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(90deg, var(--text-primary), #b0c4e8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.main-nav { display: flex; align-items: center; gap: 28px; }
.main-nav a {
  font-size: 15px;
  color: var(--text-secondary);
  position: relative;
  padding: 8px 2px;
  transition: color 0.3s;
}
.main-nav a:hover { color: var(--text-primary); }
.main-nav a.active {
  color: var(--text-primary);
}
.main-nav a.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--brand-primary), var(--accent));
  border-radius: 2px;
}
.header-cta { display: flex; align-items: center; gap: 12px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 500;
  padding: 10px 20px;
  transition: all 0.3s ease;
  white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(135deg, var(--brand-primary) 0%, var(--accent) 100%);
  color: #fff;
  box-shadow: 0 0 0 1px rgba(45,212,170,0.4), 0 0 20px rgba(45,212,170,0.25);
}
.btn-primary:hover {
  filter: brightness(1.15);
  box-shadow: 0 0 0 1px rgba(45,212,170,0.5), 0 0 28px rgba(45,212,170,0.4);
  color: #fff;
}
.btn-primary:active { transform: translateY(2px); }
.btn-lg { padding: 16px 32px; font-size: 16px; border-radius: 14px; height: 60px; min-width: 200px; }
.btn-outline {
  background: transparent;
  border: 1px solid rgba(255,255,255,0.25);
  color: var(--text-primary);
}
.btn-outline:hover { border-color: rgba(255,255,255,0.5); background: rgba(255,255,255,0.06); color: var(--text-primary); }
.btn-outline:active { transform: translateY(2px); }

/* ============ 汉堡按钮 ============ */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 10px;
}
.menu-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s;
}

/* ============ 移动端抽屉导航 ============ */
.mobile-drawer {
  position: fixed;
  top: 0;
  right: -280px;
  width: 280px;
  height: 100vh;
  background: var(--bg-secondary);
  z-index: 1000;
  box-shadow: -10px 0 40px rgba(0,0,0,0.5);
  transition: right 0.35s ease;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.mobile-drawer.open { right: 0; }
.mobile-drawer .drawer-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.mobile-drawer .drawer-brand { font-size: 18px; font-weight: 700; }
.drawer-close { font-size: 22px; color: var(--text-primary); padding: 4px 8px; }
.mobile-drawer a {
  display: block;
  padding: 14px 12px;
  font-size: 16px;
  color: var(--text-secondary);
  border-radius: 10px;
  transition: background 0.2s, color 0.2s;
}
.mobile-drawer a:hover { background: rgba(255,255,255,0.05); color: var(--text-primary); }
.mobile-drawer a.active { color: var(--brand-light); background: rgba(46,124,246,0.12); }
.mobile-drawer .drawer-cta { margin-top: 16px; }
.mobile-drawer .drawer-cta .btn { width: 100%; }
.drawer-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s;
}
.drawer-overlay.show { opacity: 1; visibility: visible; }

/* ============ Hero ============ */
.hero {
  position: relative;
  min-height: 90vh;
  display: flex;
  align-items: center;
  background: url('/assets/images/backpic/back-1.webp') center center / cover no-repeat;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(105deg, rgba(10,17,32,0.88) 40%, rgba(10,17,32,0.68) 75%, rgba(10,17,32,0.55) 100%);
}
.hero .container {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  width: 100%;
  padding-top: 40px;
  padding-bottom: 40px;
}
.hero-content { max-width: 620px; }
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(46,124,246,0.12);
  border: 1px solid rgba(46,124,246,0.3);
  color: var(--brand-light);
  font-size: 13px;
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 20px;
}
.hero-badge svg { width: 14px; height: 14px; }
.hero h1 {
  font-size: clamp(28px, 4.5vw, 44px);
  font-weight: 700;
  line-height: 1.22;
  margin-bottom: 18px;
  letter-spacing: 0.02em;
}
.hero h1 .highlight {
  background: linear-gradient(90deg, var(--brand-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-sub {
  font-size: 17px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 32px;
  max-width: 480px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-note {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 28px;
  font-size: 13px;
  color: var(--text-muted);
  flex-wrap: wrap;
}
.hero-note .note-item { display: flex; align-items: center; gap: 5px; }
.hero-note .note-item svg { width: 14px; height: 14px; stroke: var(--accent); }
.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero-visual .visual-card {
  width: 100%;
  max-width: 420px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-light);
  box-shadow: 0 30px 60px rgba(0,0,0,0.5);
  position: relative;
}
.hero-visual .visual-card img { width: 100%; height: auto; display: block; }
.hero-visual .visual-card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, transparent 70%, rgba(10,17,32,0.4));
  pointer-events: none;
}
.visual-float {
  position: absolute;
  bottom: -18px;
  left: -18px;
  background: rgba(15,26,46,0.9);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  gap: 14px;
  box-shadow: var(--shadow-card);
}
.visual-float .float-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--brand-primary), var(--accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: #fff;
  font-weight: 700;
  flex-shrink: 0;
}
.visual-float .float-text { font-size: 13px; color: var(--text-secondary); line-height: 1.4; }
.visual-float .float-text strong { display: block; color: var(--text-primary); font-size: 15px; }
.scroll-hint {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  color: var(--text-muted);
  font-size: 12px;
  z-index: 2;
}
.scroll-hint .line {
  width: 1px;
  height: 28px;
  background: linear-gradient(180deg, var(--text-muted), transparent);
  animation: scrollPulse 2s ease infinite;
}
@keyframes scrollPulse {
  0%, 100% { opacity: 0.4; transform: scaleY(0.8); }
  50% { opacity: 1; transform: scaleY(1.2); }
}

/* ============ 信任/数据条 ============ */
.trust-bar {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
}
.trust-bar .container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding-top: 24px;
  padding-bottom: 24px;
  align-items: center;
}
.trust-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 4px;
}
.trust-item .trust-num {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
  font-feature-settings: "tnum";
}
.trust-item .trust-num em { font-style: normal; color: var(--accent); }
.trust-item .trust-label {
  font-size: 13px;
  color: var(--text-muted);
}
.trust-divider { width: 1px; height: 36px; background: var(--border-color); }

/* ============ 板块通用 ============ */
.section { padding: 96px 0; position: relative; }
.section-alt { background: var(--bg-secondary); }
.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px;
}
.section-tag {
  display: inline-block;
  font-size: 13px;
  color: var(--brand-light);
  background: rgba(46,124,246,0.12);
  border-radius: 999px;
  padding: 5px 16px;
  margin-bottom: 14px;
  border: 1px solid rgba(46,124,246,0.22);
  letter-spacing: 0.04em;
}
.section h2 {
  font-size: clamp(22px, 3vw, 32px);
  margin-bottom: 14px;
  line-height: 1.3;
}
.section-desc {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.7;
}

/* ============ 功能亮点 ============ */
.features-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 20px;
}
.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  position: relative;
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  min-height: 200px;
}
.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.12), transparent);
  opacity: 0.6;
  transition: opacity 0.3s;
}
.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover), 0 0 30px rgba(46,124,246,0.08);
  border-color: rgba(46,124,246,0.3);
}
.feature-card.large { grid-row: span 1; }
.feature-card .feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(46,124,246,0.2), rgba(45,212,170,0.15));
  border: 1px solid rgba(46,124,246,0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.feature-card .feature-icon svg { width: 24px; height: 24px; stroke: var(--brand-light); }
.feature-card h3 { font-size: 19px; margin-bottom: 10px; }
.feature-card p { color: var(--text-secondary); font-size: 15px; line-height: 1.7; }
.feature-card .feature-link {
  display: inline-block;
  margin-top: 16px;
  font-size: 14px;
  color: var(--brand-light);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s;
}
.feature-card .feature-link:hover { border-bottom-color: var(--brand-light); }
.feature-stack { display: flex; flex-direction: column; gap: 20px; }

/* ============ 功能截图轮播 ============ */
.carousel-section { background: var(--bg-secondary); overflow: hidden; }
.carousel-container {
  position: relative;
  max-width: 1080px;
  margin: 0 auto;
}
.carousel-track {
  display: flex;
  transition: transform 0.4s ease;
}
.carousel-slide {
  min-width: 100%;
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 48px;
  align-items: center;
  padding: 0 20px;
}
.carousel-slide .slide-text { padding: 20px 0; }
.carousel-slide .slide-text h3 {
  font-size: 26px;
  margin-bottom: 12px;
  line-height: 1.3;
}
.carousel-slide .slide-text p {
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
  font-size: 15px;
}
.carousel-slide .slide-text .slide-divider {
  width: 48px;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-primary), var(--accent));
  border-radius: 3px;
  margin-bottom: 20px;
}
.carousel-slide .slide-text .slide-spec {
  font-size: 13px;
  color: var(--text-muted);
}
.slide-visual {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 50px rgba(0,0,0,0.45);
  border: 1px solid var(--border-light);
  transform: perspective(800px) rotateY(-2deg);
  transition: transform 0.4s;
}
.slide-visual:hover { transform: perspective(800px) rotateY(0deg); }
.slide-visual img { width: 100%; height: auto; display: block; }
.carousel-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 32px;
  gap: 24px;
}
.carousel-arrows { display: flex; gap: 12px; }
.carousel-arrow {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border-light);
  background: rgba(255,255,255,0.03);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: all 0.3s;
  font-size: 18px;
  line-height: 1;
}
.carousel-arrow:hover { border-color: var(--brand-primary); color: var(--brand-light); background: rgba(46,124,246,0.1); }
.carousel-progress { display: flex; gap: 8px; flex: 1; justify-content: center; }
.carousel-progress .dot {
  width: 28px;
  height: 3px;
  border-radius: 3px;
  background: rgba(255,255,255,0.15);
  cursor: pointer;
  transition: background 0.3s;
}
.carousel-progress .dot.active { background: linear-gradient(90deg, var(--brand-primary), var(--accent)); }

/* ============ 系统要求 ============ */
.spec-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  max-width: 860px;
  margin: 0 auto;
}
.spec-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px 30px;
  display: flex;
  align-items: center;
  gap: 20px;
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.spec-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(46,124,246,0.25);
}
.spec-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(46,124,246,0.12);
  border: 1px solid rgba(46,124,246,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.spec-icon svg { width: 22px; height: 22px; stroke: var(--accent); }
.spec-info .spec-label { font-size: 14px; color: var(--text-muted); margin-bottom: 2px; }
.spec-info .spec-value { font-size: 18px; font-weight: 700; color: var(--text-primary); font-feature-settings: "tnum"; }
.spec-info .spec-value em { font-style: normal; color: var(--accent); }

/* ============ 评价墙 ============ */
.review-section { background: var(--bg-secondary); position: relative; overflow: hidden; }
.review-section::before {
  content: "\201C";
  position: absolute;
  top: 40px;
  left: 40px;
  font-size: 240px;
  font-family: Georgia, serif;
  color: rgba(255,255,255,0.03);
  line-height: 1;
  pointer-events: none;
}
.review-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.review-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  position: relative;
  transition: transform 0.3s, box-shadow 0.3s;
}
.review-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
.review-stars {
  display: flex;
  gap: 2px;
  margin-bottom: 16px;
}
.review-stars svg { width: 16px; height: 16px; fill: var(--warning); }
.review-text {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-primary);
  margin-bottom: 20px;
}
.review-user {
  display: flex;
  align-items: center;
  gap: 12px;
}
.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(46,124,246,0.5), rgba(45,212,170,0.4));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}
.review-user .user-name { font-size: 14px; color: var(--text-primary); font-weight: 500; }
.review-user .user-role { font-size: 13px; color: var(--text-muted); }

/* ============ 下载行动区 ============ */
.download-cta .container {
  max-width: 900px;
  text-align: center;
}
.download-cta h2 { font-size: clamp(22px, 3vw, 32px); margin-bottom: 12px; }
.download-cta .section-desc { max-width: 600px; margin: 0 auto 32px; }
.download-cta .cta-buttons { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; margin-bottom: 18px; }
.env-note {
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}
.env-note .env-icon { display: inline-flex; align-items: center; gap: 4px; }
.env-note .env-icon svg { width: 14px; height: 14px; stroke: var(--accent); }

/* ============ 资讯列表 ============ */
.news-section { background: var(--bg-secondary); }
.news-list { max-width: 860px; margin: 0 auto; display: flex; flex-direction: column; gap: 14px; }
.news-card {
  display: block;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.news-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(46,124,246,0.25);
}
.news-card .news-row { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.news-card .news-info { flex: 1; }
.news-card h3 { font-size: 17px; margin-bottom: 6px; color: var(--text-primary); transition: color 0.3s; }
.news-card:hover h3 { color: var(--brand-light); }
.news-card .news-excerpt {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.65;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.news-card .news-meta { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.news-cat {
  font-size: 12px;
  background: rgba(46,124,246,0.15);
  color: var(--brand-light);
  border-radius: 999px;
  padding: 4px 12px;
  white-space: nowrap;
}
.news-date {
  font-size: 13px;
  color: var(--text-muted);
  white-space: nowrap;
  font-feature-settings: "tnum";
}
.news-empty {
  border: 2px dashed rgba(255,255,255,0.14);
  border-radius: var(--radius-md);
  padding: 48px;
  text-align: center;
  color: var(--text-muted);
  font-size: 15px;
}
.news-empty svg { width: 36px; height: 36px; margin: 0 auto 12px; stroke: var(--text-muted); }

/* ============ FAQ ============ */
.faq-list { max-width: 760px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.3s, background 0.3s;
}
.faq-item.active { border-color: rgba(46,124,246,0.3); background: rgba(46,124,246,0.04); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 500;
  color: var(--text-primary);
  user-select: none;
}
.faq-question .faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s, background 0.3s;
  flex-shrink: 0;
  font-size: 18px;
  font-weight: 300;
  color: var(--brand-light);
}
.faq-item.active .faq-icon { transform: rotate(45deg); background: rgba(46,124,246,0.15); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}
.faq-answer .answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.75;
}

/* ============ 最终 CTA ============ */
.final-cta {
  position: relative;
  min-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: url('/assets/images/backpic/back-2.webp') center center / cover no-repeat;
}
.final-cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(10,17,32,0.78);
}
.final-cta .container { position: relative; z-index: 2; max-width: 700px; }
.final-cta h2 { font-size: clamp(22px, 3.2vw, 34px); margin-bottom: 16px; }
.final-cta p { color: var(--text-secondary); margin-bottom: 28px; font-size: 16px; }
.final-cta .cta-buttons { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; }

/* ============ 页脚 ============ */
.site-footer { background: #060B14; border-top: 1px solid rgba(46,124,246,0.15); position: relative; }
.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(46,124,246,0.4), rgba(45,212,170,0.4), transparent);
}
.footer-main {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr 1fr;
  gap: 40px;
  padding: 56px 0 40px;
}
.footer-brand .logo-text { font-size: 20px; margin-bottom: 14px; display: inline-block; }
.footer-brand p { font-size: 14px; color: var(--text-muted); line-height: 1.7; max-width: 280px; }
.footer-col h4 {
  font-size: 15px;
  color: var(--text-primary);
  margin-bottom: 18px;
  position: relative;
  padding-bottom: 10px;
}
.footer-col h4::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 24px;
  height: 2px;
  background: linear-gradient(90deg, var(--brand-primary), var(--accent));
  border-radius: 2px;
}
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col ul a { font-size: 14px; color: var(--text-secondary); transition: color 0.3s, padding-left 0.3s; }
.footer-col ul a:hover { color: var(--brand-light); padding-left: 4px; }
.footer-contact p { font-size: 14px; color: var(--text-secondary); line-height: 1.8; }
.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding: 20px 0;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
}

/* ============ 响应式 ============ */
@media (max-width: 1023px) {
  .main-nav { display: none; }
  .menu-toggle { display: flex; }
  .header-cta .btn { display: none; }
  .hero .container { grid-template-columns: 1fr; gap: 32px; }
  .hero-visual { margin-top: 12px; }
  .hero-visual .visual-card { max-width: 100%; }
  .features-grid { grid-template-columns: 1fr; }
  .feature-stack { flex-direction: row; }
  .carousel-slide { grid-template-columns: 1fr; gap: 24px; }
  .review-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-main { grid-template-columns: repeat(2, 1fr); }
  .trust-bar .container { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 767px) {
  .section { padding: 56px 0; }
  .top-bar .top-msg { display: none; }
  .trust-bar .container { grid-template-columns: repeat(2, 1fr); gap: 12px; padding-top: 16px; padding-bottom: 16px; }
  .feature-stack { flex-direction: column; }
  .review-grid { grid-template-columns: 1fr; }
  .spec-grid { grid-template-columns: 1fr; }
  .news-card .news-row { flex-direction: column; align-items: flex-start; gap: 10px; }
  .news-card .news-meta { width: 100%; justify-content: space-between; }
  .footer-main { grid-template-columns: 1fr; gap: 32px; }
  .hero-actions, .cta-buttons { flex-direction: column; width: 100%; }
  .hero-actions .btn, .cta-buttons .btn { width: 100%; }
  .hero { min-height: auto; padding: 60px 0; }
  .visual-float { display: none; }
  .carousel-slide { padding: 0; }
  .carousel-controls { flex-direction: column; align-items: center; }
  .btn-lg { height: 54px; min-width: 0; padding: 14px 24px; }
}
@media (max-width: 520px) {
  .trust-item .trust-num { font-size: 20px; }
  .spec-card { flex-direction: column; text-align: center; padding: 24px; }
  .spec-icon { margin: 0 auto; }
  .faq-question { padding: 16px 18px; font-size: 15px; }
  .faq-answer .answer-inner { padding: 0 18px 16px; }
}

/* roulang page: category1 */
:root {
  --bg-primary: #0A1120;
  --bg-secondary: #0F1A2E;
  --brand-blue: #2E7CF6;
  --brand-sky: #38BDF8;
  --brand-green: #2DD4A0;
  --warning: #F5B056;
  --error: #F87171;
  --text-main: #E7EDF7;
  --text-sub: #94A3BC;
  --text-muted: #5D6F88;
  --border: rgba(255, 255, 255, 0.08);
  --border-light: rgba(255, 255, 255, 0.12);
  --glass: rgba(255, 255, 255, 0.03);
  --radius-large: 20px;
  --radius-medium: 14px;
  --radius-small: 12px;
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.30);
  --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.45);
  --container: 1200px;
  --space-section: 96px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
  background: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.75;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; }
button { font-family: inherit; }
ul, ol { list-style: none; }

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 20px;
}

.page-bg {
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(600px 400px at 8% -10%, rgba(46, 124, 246, 0.20), transparent 60%),
    radial-gradient(800px 500px at 110% 35%, rgba(45, 212, 160, 0.12), transparent 60%),
    var(--bg-primary);
}

.page-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 42px 42px;
}

/* ===== Topbar ===== */
.topbar {
  height: 34px;
  background: #060B16;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 13px;
  color: var(--text-sub);
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.topbar-domain {
  color: var(--text-muted);
  font-weight: 600;
  font-feature-settings: "tnum";
  letter-spacing: 0.02em;
}

.topbar-msg {
  color: var(--text-muted);
  letter-spacing: 0.03em;
}

.topbar-link {
  color: var(--brand-sky);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.topbar-link:hover { color: var(--brand-green); }

/* ===== Main Nav ===== */
.main-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 72px;
  background: rgba(10, 17, 32, 0.75);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  position: relative;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}

.logo-badge {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, #2E7CF6, #2DD4A0);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 18px;
  box-shadow: 0 0 16px rgba(45, 212, 160, 0.4);
  font-family: "Inter", sans-serif;
}

.logo-text {
  font-size: 20px;
  font-weight: 700;
  background: linear-gradient(90deg, #E7EDF7, #b0c4e8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
  margin-right: 32px;
}

.nav-links a {
  color: var(--text-sub);
  font-size: 15px;
  text-decoration: none;
  padding: 8px 2px;
  position: relative;
  transition: color 0.3s;
  letter-spacing: 0.02em;
}

.nav-links a:hover { color: var(--text-main); }

.nav-links a.active {
  color: var(--text-main);
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, #2E7CF6, #2DD4A0);
  box-shadow: 0 0 8px rgba(45, 212, 170, 0.5);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 10px;
  border-radius: 8px;
  align-items: center;
  justify-content: center;
  transition: background 0.3s;
}

.nav-toggle:hover { background: rgba(255, 255, 255, 0.05); }

.nav-toggle span {
  display: block;
  height: 2px;
  width: 22px;
  background: var(--text-main);
  border-radius: 2px;
  transition: all 0.3s;
}

.mobile-menu {
  display: none;
  flex-direction: column;
  position: absolute;
  top: 72px;
  left: 0;
  right: 0;
  background: rgba(10, 17, 32, 0.98);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding: 12px 20px 20px;
  gap: 6px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.mobile-menu.open { display: flex; }

.mobile-menu a {
  display: block;
  padding: 14px 12px;
  border-radius: 10px;
  color: var(--text-sub);
  text-decoration: none;
  font-size: 16px;
  transition: background 0.3s, color 0.3s;
}

.mobile-menu a:hover,
.mobile-menu a.active {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
}

.mobile-menu .btn {
  margin-top: 10px;
  width: 100%;
}

/* ===== Button ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  cursor: pointer;
  font-family: inherit;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-small);
  text-decoration: none;
  transition: all 0.25s ease;
  line-height: 1;
  padding: 0 20px;
  height: 40px;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #2E7CF6, #2DD4A0);
  color: #fff;
  box-shadow: 0 0 0 1px rgba(45, 212, 170, 0.4), 0 0 20px rgba(45, 212, 170, 0.35);
}

.btn-primary:hover {
  filter: brightness(1.1);
  box-shadow: 0 0 0 1px rgba(45, 212, 170, 0.5), 0 0 32px rgba(45, 212, 170, 0.45);
  transform: translateY(-1px);
}

.btn-primary:active { transform: translateY(2px); }

.btn-secondary {
  background: rgba(255, 255, 255, 0.03);
  color: var(--text-main);
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.5);
  background: rgba(255, 255, 255, 0.06);
}

.btn-secondary:active { transform: translateY(2px); }

.btn-lg { height: 48px; padding: 0 28px; font-size: 16px; }
.btn-xl { height: 60px; padding: 0 40px; font-size: 17px; }

/* ===== Page Hero ===== */
.page-hero {
  position: relative;
  min-height: 360px;
  display: flex;
  align-items: center;
  background-size: cover;
  background-position: center;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10, 17, 32, 0.72), rgba(10, 17, 32, 0.86));
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 80px 0;
  width: 100%;
}

.hero-badge {
  display: inline-flex;
  padding: 6px 18px;
  border-radius: 999px;
  background: rgba(46, 124, 246, 0.15);
  border: 1px solid rgba(46, 124, 246, 0.3);
  color: var(--brand-sky);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.05em;
  margin-bottom: 20px;
}

.hero-content h1 {
  font-size: clamp(32px, 4.5vw, 46px);
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: 0.02em;
}

.hero-content p {
  max-width: 680px;
  margin: 0 auto 32px;
  color: var(--text-sub);
  font-size: 17px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== Section ===== */
.section { padding: var(--space-section) 0; }

.section-head {
  text-align: center;
  margin-bottom: 52px;
}

.section-tag {
  display: inline-flex;
  padding: 5px 14px;
  border-radius: 999px;
  background: rgba(46, 124, 246, 0.12);
  color: var(--brand-sky);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}

.section-head h2 {
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  margin-bottom: 14px;
  letter-spacing: 0.02em;
}

.section-head p {
  color: var(--text-sub);
  max-width: 600px;
  margin: 0 auto;
  font-size: 15px;
}

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  grid-template-rows: auto auto;
  gap: 24px;
}

.feature-main {
  grid-row: 1 / 3;
}

.feature-card {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-large);
  padding: 36px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.14), transparent);
}

.feature-card::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(46, 124, 246, 0.2), transparent);
  opacity: 0;
  transition: opacity 0.3s;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover), 0 0 30px rgba(46, 124, 246, 0.08);
  border-color: rgba(46, 124, 246, 0.3);
}

.feature-card:hover::after { opacity: 1; }

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(46, 124, 246, 0.2), rgba(45, 212, 160, 0.2));
  margin-bottom: 22px;
  color: var(--brand-sky);
}

.feature-icon svg {
  width: 28px;
  height: 28px;
  stroke: currentColor;
  stroke-width: 1.5;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: 0.02em;
}

.feature-card p {
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 16px;
}

.feature-card .feature-link {
  color: var(--brand-sky);
  font-size: 14px;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.feature-card .feature-link:hover {
  color: var(--brand-green);
  text-decoration: underline;
}

.feature-img {
  margin-top: 24px;
  border-radius: var(--radius-medium);
  overflow: hidden;
  border: 1px solid var(--border);
}

.feature-img img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.feature-main:hover .feature-img img { transform: scale(1.03); }

/* ===== Gallery ===== */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.gallery-item {
  border-radius: var(--radius-large);
  overflow: hidden;
  border: 1px solid var(--border);
  position: relative;
  aspect-ratio: 4 / 3;
  background: var(--bg-secondary);
  transition: border-color 0.3s, box-shadow 0.3s;
}

.gallery-item:hover {
  border-color: rgba(46, 124, 246, 0.35);
  box-shadow: var(--shadow-hover);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.gallery-item:hover img { transform: scale(1.04); }

.gallery-label {
  position: absolute;
  left: 16px;
  bottom: 16px;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(10, 17, 32, 0.72);
  backdrop-filter: blur(8px);
  color: var(--text-main);
  font-size: 13px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  letter-spacing: 0.02em;
}

/* ===== Specs ===== */
.specs-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.spec-card {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-medium);
  padding: 30px;
  transition: all 0.3s ease;
}

.spec-card:hover {
  border-color: rgba(45, 212, 160, 0.3);
  box-shadow: var(--shadow-hover);
  transform: translateY(-4px);
}

.spec-icon {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  border-radius: 12px;
  background: rgba(45, 212, 160, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--brand-green);
}

.spec-icon svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  stroke-width: 1.5;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.spec-card h4 {
  font-size: 14px;
  color: var(--text-sub);
  font-weight: 500;
  margin-bottom: 6px;
}

.spec-value {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-main);
  font-feature-settings: "tnum";
  letter-spacing: 0.01em;
}

/* ===== Timeline ===== */
.update-timeline {
  max-width: 760px;
  margin: 0 auto;
  position: relative;
  padding-left: 34px;
}

.update-timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(180deg, rgba(46, 124, 246, 0.5), rgba(45, 212, 160, 0.3));
}

.timeline-item {
  position: relative;
  margin-bottom: 24px;
}

.timeline-dot {
  position: absolute;
  left: -34px;
  top: 24px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 2px solid var(--brand-sky);
  box-shadow: 0 0 0 4px rgba(46, 124, 246, 0.15);
}

.timeline-card {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-medium);
  padding: 20px 24px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: all 0.3s ease;
}

.timeline-card:hover {
  border-color: rgba(46, 124, 246, 0.3);
  transform: translateX(6px);
  box-shadow: var(--shadow-card);
}

.version-badge {
  display: inline-flex;
  padding: 4px 14px;
  border-radius: 999px;
  background: linear-gradient(135deg, rgba(46, 124, 246, 0.2), rgba(45, 212, 160, 0.2));
  color: var(--brand-sky);
  font-weight: 700;
  font-size: 14px;
  font-feature-settings: "tnum";
  flex-shrink: 0;
  letter-spacing: 0.02em;
}

.timeline-card p {
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.6;
}

/* ===== FAQ ===== */
.faq-cols {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 56px;
  align-items: start;
}

.faq-side h2 {
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  margin-bottom: 14px;
  letter-spacing: 0.02em;
}

.faq-side p {
  color: var(--text-sub);
  margin-bottom: 28px;
  font-size: 15px;
  line-height: 1.7;
}

.faq-side .btn { margin-bottom: 8px; }

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-medium);
  overflow: hidden;
  transition: border-color 0.3s, background 0.3s, box-shadow 0.3s;
}

.faq-item.open {
  border-color: rgba(46, 124, 246, 0.35);
  background: rgba(255, 255, 255, 0.05);
  box-shadow: var(--shadow-card);
}

.faq-q {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 18px 22px;
  background: transparent;
  border: none;
  color: var(--text-main);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  letter-spacing: 0.01em;
  transition: color 0.3s;
}

.faq-q:hover { color: var(--brand-sky); }

.faq-icon {
  position: relative;
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  background: var(--brand-sky);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.faq-icon::before {
  top: 8px;
  left: 0;
  width: 18px;
  height: 2px;
}

.faq-icon::after {
  top: 0;
  left: 8px;
  width: 2px;
  height: 18px;
}

.faq-item.open .faq-icon::after {
  transform: rotate(90deg);
  opacity: 0;
}

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}

.faq-a-inner {
  padding: 0 22px 20px;
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.75;
}

.faq-item.open .faq-a { max-height: 500px; }

/* ===== CTA ===== */
.cta {
  position: relative;
  background-image: url('/assets/images/backpic/back-2.webp');
  background-size: cover;
  background-position: center;
  overflow: hidden;
}

.cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(10, 17, 32, 0.82);
}

.cta-inner {
  position: relative;
  text-align: center;
  padding: 88px 0;
}

.cta-inner h2 {
  font-size: clamp(26px, 3.5vw, 36px);
  font-weight: 700;
  margin-bottom: 14px;
  letter-spacing: 0.02em;
}

.cta-inner p {
  color: var(--text-sub);
  margin-bottom: 32px;
  font-size: 16px;
}

.cta-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 18px;
  flex-wrap: wrap;
}

.cta-note {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* ===== Footer ===== */
.site-footer {
  background: #060B16;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  position: relative;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(46, 124, 246, 0.3), rgba(45, 212, 160, 0.3), transparent);
}

.footer-main {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding: 64px 0 48px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 14px;
  margin-top: 14px;
  max-width: 320px;
  line-height: 1.7;
}

.footer-col h4,
.footer-contact h4 {
  font-size: 15px;
  color: var(--text-main);
  margin-bottom: 16px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  color: var(--text-sub);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s;
}

.footer-col a:hover {
  color: var(--brand-sky);
}

.footer-contact p {
  color: var(--text-sub);
  font-size: 14px;
  margin-bottom: 10px;
  font-feature-settings: "tnum";
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding: 20px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
  letter-spacing: 0.02em;
}

/* ===== Responsive ===== */
@media (max-width: 1023px) {
  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-toggle { display: flex; }

  .section { padding: 72px 0; }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .feature-main { grid-row: auto; }

  .gallery-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .specs-grid { grid-template-columns: 1fr; }

  .faq-cols {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .footer-main {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 767px) {
  .section { padding: 56px 0; }

  .hero-content { padding: 60px 0; }

  .gallery-grid { grid-template-columns: 1fr; }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 28px;
    padding: 48px 0 32px;
  }

  .hero-actions,
  .cta-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn,
  .cta-actions .btn {
    width: 100%;
  }

  .topbar-msg { display: none; }

  .topbar-inner {
    justify-content: space-between;
  }

  .feature-card { padding: 26px; }

  .spec-card { padding: 24px; }

  .timeline-card {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .section-head { margin-bottom: 36px; }
}

@media (max-width: 520px) {
  .container { padding: 0 16px; }

  .specs-grid { gap: 16px; }

  .feature-card { padding: 22px; }

  .update-timeline { padding-left: 24px; }

  .timeline-dot { left: -24px; }

  .btn-xl { height: 54px; padding: 0 28px; font-size: 16px; }
}

/* roulang page: article */
:root {
            --bg-main: #0A1120;
            --bg-secondary: #0F1A2E;
            --brand: #2E7CF6;
            --brand-light: #38BDF8;
            --accent: #2DD4A0;
            --text-main: #E7EDF7;
            --text-sub: #94A3BC;
            --text-weak: #5D6F88;
            --border: rgba(255, 255, 255, 0.08);
            --card-bg: rgba(255, 255, 255, 0.03);
            --radius-lg: 20px;
            --radius-md: 14px;
            --radius-sm: 12px;
            --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.30);
            --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.45);
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
            background:
                radial-gradient(1200px 600px at 10% -10%, rgba(46, 124, 246, 0.18), transparent 60%),
                radial-gradient(900px 500px at 90% 110%, rgba(45, 212, 160, 0.12), transparent 60%),
                var(--bg-main);
            color: var(--text-main);
            line-height: 1.75;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
        }

        body::before {
            content: "";
            position: fixed;
            inset: 0;
            background-image:
                linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
                linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
            background-size: 50px 50px;
            pointer-events: none;
            z-index: 0;
        }

        a {
            color: var(--text-main);
            text-decoration: none;
            transition: color 0.2s ease;
        }

        a:hover {
            color: var(--brand-light);
        }

        img {
            max-width: 100%;
            display: block;
        }

        button,
        input {
            font-family: inherit;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding-left: 20px;
            padding-right: 20px;
        }

        ::selection {
            background: rgba(46, 124, 246, 0.4);
            color: #fff;
        }

        :focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        .topbar {
            background: #060D1A;
            border-bottom: 1px solid rgba(255, 255, 255, 0.06);
            height: 34px;
            display: flex;
            align-items: center;
            position: relative;
            z-index: 90;
        }

        .topbar-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 16px;
            width: 100%;
            font-size: 13px;
        }

        .topbar-domain {
            color: var(--text-weak);
            font-weight: 600;
            letter-spacing: 0.02em;
            white-space: nowrap;
        }

        .topbar-msg {
            color: var(--text-sub);
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
            text-align: center;
            flex: 1;
        }

        .topbar-entry {
            color: var(--brand-light);
            font-weight: 500;
            white-space: nowrap;
            padding: 4px 12px;
            border: 1px solid rgba(56, 189, 248, 0.3);
            border-radius: 999px;
            transition: all 0.2s ease;
        }

        .topbar-entry:hover {
            background: rgba(56, 189, 248, 0.1);
            color: var(--brand-light);
            border-color: rgba(56, 189, 248, 0.6);
        }

        .site-header {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(10, 17, 32, 0.78);
            backdrop-filter: blur(14px);
            -webkit-backdrop-filter: blur(14px);
            border-bottom: 1px solid rgba(255, 255, 255, 0.06);
        }

        .nav-wrap {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 28px;
            height: 72px;
        }

        .brand {
            display: inline-flex;
            align-items: center;
            gap: 12px;
            flex-shrink: 0;
        }

        .brand-logo {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 38px;
            height: 38px;
            flex-shrink: 0;
        }

        .brand-logo svg {
            width: 36px;
            height: 36px;
        }

        .logo-text {
            font-size: 22px;
            font-weight: 700;
            letter-spacing: 0.02em;
            background: linear-gradient(90deg, #E7EDF7, #b0c4e8);
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
            white-space: nowrap;
        }

        .main-nav {
            display: flex;
            align-items: center;
            gap: 28px;
            margin-left: auto;
        }

        .main-nav a {
            font-size: 15px;
            font-weight: 500;
            color: var(--text-sub);
            padding: 10px 2px;
            position: relative;
            transition: color 0.2s ease;
            white-space: nowrap;
        }

        .main-nav a:hover {
            color: var(--text-main);
        }

        .main-nav a.active {
            color: var(--text-main);
        }

        .main-nav a.active::after {
            content: "";
            position: absolute;
            left: 0;
            right: 0;
            bottom: 0;
            height: 2px;
            border-radius: 2px;
            background: linear-gradient(90deg, var(--brand), var(--accent));
            box-shadow: 0 0 12px rgba(45, 212, 160, 0.4);
        }

        .nav-cta {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: linear-gradient(135deg, #2E7CF6, #2DD4A0);
            color: #fff;
            border: none;
            border-radius: 12px;
            padding: 10px 20px;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            box-shadow: 0 0 20px rgba(45, 212, 170, 0.25), 0 0 0 1px rgba(45, 212, 170, 0.4);
            transition: all 0.25s ease;
            flex-shrink: 0;
        }

        .nav-cta:hover {
            color: #fff;
            transform: translateY(-2px);
            box-shadow: 0 0 30px rgba(45, 212, 170, 0.4);
            filter: brightness(1.08);
        }

        .nav-cta:active {
            transform: translateY(0);
        }

        .nav-toggle {
            display: none;
            align-items: center;
            justify-content: center;
            width: 44px;
            height: 44px;
            background: rgba(255, 255, 255, 0.06);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 12px;
            color: var(--text-main);
            cursor: pointer;
            flex-shrink: 0;
        }

        .nav-toggle:hover {
            border-color: rgba(56, 189, 248, 0.4);
            background: rgba(56, 189, 248, 0.08);
        }

        .btn-primary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: linear-gradient(135deg, #2E7CF6, #2DD4A0);
            color: #fff;
            border: none;
            border-radius: 12px;
            padding: 12px 28px;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            box-shadow: 0 0 20px rgba(45, 212, 170, 0.25), 0 0 0 1px rgba(45, 212, 170, 0.4);
            transition: all 0.25s ease;
            text-decoration: none;
        }

        .btn-primary:hover {
            color: #fff;
            transform: translateY(-2px);
            filter: brightness(1.08);
            box-shadow: 0 0 30px rgba(45, 212, 170, 0.45);
        }

        .btn-primary:active {
            transform: translateY(0);
        }

        .btn-secondary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: transparent;
            color: var(--text-main);
            border: 1px solid rgba(255, 255, 255, 0.25);
            border-radius: 12px;
            padding: 12px 28px;
            font-size: 15px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.25s ease;
            text-decoration: none;
        }

        .btn-secondary:hover {
            color: var(--text-main);
            border-color: var(--brand-light);
            background: rgba(255, 255, 255, 0.06);
            transform: translateY(-2px);
        }

        .btn-secondary:active {
            transform: translateY(0);
        }

        .article-main {
            position: relative;
            z-index: 1;
            padding-top: 48px;
            padding-bottom: 80px;
        }

        .article-container {
            max-width: 860px;
        }

        .breadcrumb {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 14px;
            color: var(--text-weak);
            margin-bottom: 20px;
            flex-wrap: wrap;
        }

        .breadcrumb a {
            color: var(--text-sub);
            transition: color 0.2s ease;
        }

        .breadcrumb a:hover {
            color: var(--brand-light);
        }

        .breadcrumb-sep {
            color: var(--text-weak);
        }

        .breadcrumb-current {
            color: var(--text-sub);
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
            max-width: 320px;
        }

        .article-card {
            background: var(--card-bg);
            border: 1px solid var(--border);
            border-radius: var(--radius-lg);
            padding: clamp(28px, 4.5vw, 56px);
            box-shadow: var(--shadow-card);
            position: relative;
            overflow: hidden;
        }

        .article-card::before {
            content: "";
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 1px;
            background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
        }

        .article-header {
            margin-bottom: 28px;
        }

        .article-cat {
            display: inline-flex;
            align-items: center;
            padding: 6px 16px;
            border-radius: 999px;
            background: rgba(46, 124, 246, 0.15);
            color: var(--brand-light);
            font-size: 13px;
            font-weight: 600;
            margin-bottom: 16px;
            border: 1px solid rgba(46, 124, 246, 0.2);
        }

        .article-header h1 {
            font-size: clamp(26px, 4vw, 38px);
            font-weight: 700;
            line-height: 1.35;
            letter-spacing: 0.02em;
            margin-bottom: 16px;
        }

        .article-meta {
            display: flex;
            flex-wrap: wrap;
            gap: 8px 20px;
            color: var(--text-weak);
            font-size: 13px;
            border-top: 1px solid rgba(255, 255, 255, 0.06);
            padding-top: 16px;
        }

        .article-cover {
            border-radius: 16px;
            overflow: hidden;
            margin-bottom: 28px;
            border: 1px solid rgba(255, 255, 255, 0.06);
        }

        .article-cover img {
            width: 100%;
            height: auto;
            display: block;
        }

        .article-content {
            font-size: 16px;
            line-height: 1.8;
            color: var(--text-main);
        }

        .article-content p {
            margin-bottom: 20px;
        }

        .article-content h2 {
            font-size: clamp(20px, 2.6vw, 26px);
            font-weight: 700;
            margin: 36px 0 16px;
            letter-spacing: 0.02em;
            line-height: 1.4;
        }

        .article-content h2::before {
            content: "";
            display: inline-block;
            width: 4px;
            height: 18px;
            background: linear-gradient(180deg, var(--brand), var(--accent));
            border-radius: 2px;
            margin-right: 10px;
            vertical-align: -2px;
        }

        .article-content h3 {
            font-size: 18px;
            font-weight: 700;
            margin: 28px 0 12px;
            color: var(--text-main);
        }

        .article-content ul,
        .article-content ol {
            margin: 0 0 20px;
            padding-left: 22px;
        }

        .article-content li {
            margin-bottom: 8px;
        }

        .article-content a {
            color: var(--brand-light);
            border-bottom: 1px solid rgba(56, 189, 248, 0.3);
            transition: border-color 0.2s ease;
        }

        .article-content a:hover {
            border-bottom-color: var(--accent);
            color: var(--accent);
        }

        .article-content blockquote {
            border-left: 3px solid var(--accent);
            background: rgba(45, 212, 160, 0.06);
            padding: 16px 20px;
            margin: 24px 0;
            border-radius: 0 12px 12px 0;
            color: var(--text-sub);
            font-style: normal;
        }

        .article-content blockquote p {
            margin-bottom: 0;
        }

        .article-content img {
            border-radius: 14px;
            margin: 24px 0;
            border: 1px solid rgba(255, 255, 255, 0.06);
            width: 100%;
        }

        .article-content pre {
            background: #060D1A;
            border: 1px solid rgba(255, 255, 255, 0.08);
            border-radius: 12px;
            padding: 18px 20px;
            overflow-x: auto;
            margin: 24px 0;
            font-size: 14px;
            line-height: 1.6;
            color: #e2e8f0;
        }

        .article-content code {
            background: rgba(255, 255, 255, 0.08);
            padding: 2px 6px;
            border-radius: 6px;
            font-size: 0.9em;
            color: var(--brand-light);
        }

        .article-content pre code {
            background: transparent;
            padding: 0;
            color: inherit;
        }

        .empty-article {
            text-align: center;
            padding: 48px 24px;
            border: 1px dashed rgba(255, 255, 255, 0.18);
            border-radius: 16px;
            color: var(--text-sub);
        }

        .empty-article p {
            font-size: 16px;
            margin-bottom: 20px;
        }

        .article-back {
            margin-top: 36px;
            padding-top: 24px;
            border-top: 1px solid rgba(255, 255, 255, 0.06);
            display: flex;
            justify-content: center;
        }

        .related-section {
            margin-top: 48px;
        }

        .section-title {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            font-size: 24px;
            font-weight: 700;
            letter-spacing: 0.02em;
            margin-bottom: 24px;
        }

        .section-title::before {
            content: "";
            width: 4px;
            height: 20px;
            border-radius: 2px;
            background: linear-gradient(180deg, var(--brand), var(--accent));
        }

        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
        }

        .related-card {
            background: var(--card-bg);
            border: 1px solid var(--border);
            border-radius: 16px;
            overflow: hidden;
            transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
        }

        .related-card:hover {
            transform: translateY(-4px);
            border-color: rgba(45, 212, 160, 0.4);
            box-shadow: var(--shadow-hover), 0 0 24px rgba(45, 212, 160, 0.12);
        }

        .related-card img {
            width: 100%;
            height: 160px;
            object-fit: cover;
            display: block;
        }

        .related-info {
            padding: 20px;
        }

        .related-info h3 {
            font-size: 17px;
            font-weight: 600;
            margin-bottom: 8px;
            color: var(--text-main);
        }

        .related-info p {
            font-size: 14px;
            color: var(--text-sub);
            line-height: 1.6;
            margin-bottom: 12px;
        }

        .related-info .related-link {
            font-size: 13px;
            font-weight: 600;
            color: var(--brand-light);
            display: inline-flex;
            align-items: center;
            gap: 4px;
        }

        .related-info .related-link:hover {
            color: var(--accent);
        }

        .cta-section {
            margin-top: 56px;
            padding: 64px 32px;
            text-align: center;
            border-radius: var(--radius-lg);
            background:
                linear-gradient(rgba(10, 17, 32, 0.88), rgba(10, 17, 32, 0.92)),
                url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
            border: 1px solid rgba(255, 255, 255, 0.08);
            position: relative;
            overflow: hidden;
        }

        .cta-section::before {
            content: "";
            position: absolute;
            top: 0;
            left: 10%;
            right: 10%;
            height: 1px;
            background: linear-gradient(90deg, transparent, rgba(45, 212, 160, 0.5), transparent);
        }

        .cta-section h2 {
            font-size: clamp(22px, 3vw, 30px);
            font-weight: 700;
            margin-bottom: 12px;
            letter-spacing: 0.02em;
        }

        .cta-section p {
            color: var(--text-sub);
            font-size: 15px;
            max-width: 560px;
            margin: 0 auto 28px;
            line-height: 1.7;
        }

        .cta-buttons {
            display: flex;
            justify-content: center;
            gap: 14px;
            flex-wrap: wrap;
        }

        .site-footer {
            background: #060D1A;
            border-top: 1px solid rgba(45, 212, 160, 0.2);
            position: relative;
            z-index: 1;
        }

        .site-footer::before {
            content: "";
            position: absolute;
            top: -1px;
            left: 0;
            right: 0;
            height: 1px;
            background: linear-gradient(90deg, transparent, rgba(45, 212, 160, 0.5), transparent);
        }

        .footer-main {
            display: grid;
            grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
            gap: 40px;
            padding: 56px 0 40px;
        }

        .footer-brand .logo-text {
            font-size: 20px;
            font-weight: 700;
            background: linear-gradient(90deg, #E7EDF7, #b0c4e8);
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
            display: inline-block;
            margin-bottom: 14px;
        }

        .footer-brand p {
            color: var(--text-weak);
            font-size: 14px;
            line-height: 1.7;
            max-width: 320px;
        }

        .footer-col h4,
        .footer-contact h4 {
            color: var(--text-main);
            font-size: 15px;
            font-weight: 600;
            margin-bottom: 16px;
        }

        .footer-col ul {
            list-style: none;
        }

        .footer-col li {
            margin-bottom: 10px;
        }

        .footer-col a {
            color: var(--text-weak);
            font-size: 14px;
            transition: color 0.2s ease;
        }

        .footer-col a:hover {
            color: var(--brand-light);
        }

        .footer-contact p {
            color: var(--text-weak);
            font-size: 14px;
            margin-bottom: 8px;
        }

        .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.06);
            padding: 20px 0;
            text-align: center;
        }

        .footer-bottom .container {
            color: var(--text-weak);
            font-size: 13px;
        }

        @media (max-width: 1024px) {
            .nav-wrap {
                gap: 16px;
            }

            .main-nav {
                position: fixed;
                top: 0;
                right: 0;
                bottom: 0;
                width: 280px;
                background: rgba(10, 17, 32, 0.98);
                backdrop-filter: blur(16px);
                -webkit-backdrop-filter: blur(16px);
                flex-direction: column;
                align-items: flex-start;
                gap: 8px;
                padding: 88px 24px 32px;
                transform: translateX(100%);
                transition: transform 0.3s ease;
                z-index: 1000;
                border-left: 1px solid rgba(255, 255, 255, 0.08);
                margin-left: 0;
            }

            .main-nav.open {
                transform: translateX(0);
            }

            .main-nav a {
                display: block;
                width: 100%;
                padding: 12px 8px;
                font-size: 16px;
                border-bottom: 1px solid rgba(255, 255, 255, 0.04);
                border-radius: 8px;
            }

            .main-nav a:hover {
                background: rgba(255, 255, 255, 0.04);
                color: var(--brand-light);
            }

            .main-nav a.active::after {
                left: 8px;
                right: auto;
                width: 40px;
                height: 2px;
            }

            .nav-cta {
                display: none;
            }

            .nav-toggle {
                display: inline-flex;
            }

            .related-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (max-width: 768px) {
            .topbar-msg {
                display: none;
            }

            .topbar-inner {
                justify-content: space-between;
            }

            .footer-main {
                grid-template-columns: 1fr 1fr;
                gap: 28px;
                padding: 40px 0 28px;
            }

            .footer-brand {
                grid-column: 1 / -1;
            }

            .related-grid {
                grid-template-columns: 1fr;
            }

            .cta-section {
                padding: 48px 20px;
            }

            .article-card {
                padding: 24px;
            }

            .article-back {
                justify-content: center;
            }
        }

        @media (max-width: 520px) {
            .container {
                padding-left: 16px;
                padding-right: 16px;
            }

            .logo-text {
                font-size: 18px;
            }

            .brand-logo {
                width: 32px;
                height: 32px;
            }

            .brand-logo svg {
                width: 30px;
                height: 30px;
            }

            .nav-wrap {
                height: 64px;
            }

            .article-main {
                padding-top: 32px;
                padding-bottom: 56px;
            }

            .breadcrumb-current {
                max-width: 180px;
            }

            .article-header h1 {
                font-size: 24px;
            }

            .cta-buttons {
                flex-direction: column;
            }

            .cta-buttons .btn-primary,
            .cta-buttons .btn-secondary {
                width: 100%;
                justify-content: center;
            }

            .footer-main {
                grid-template-columns: 1fr;
                gap: 24px;
            }

            .footer-col ul {
                display: flex;
                flex-wrap: wrap;
                gap: 12px 24px;
            }

            .footer-col li {
                margin-bottom: 0;
            }
        }

/* roulang page: category2 */
:root {
  --bg: #0A1120;
  --bg-2: #0F1A2E;
  --primary: #2E7CF6;
  --primary-light: #38BDF8;
  --accent: #2DD4A0;
  --warning: #F5B056;
  --error: #F87171;
  --text: #E7EDF7;
  --text-2: #94A3BC;
  --text-3: #5D6F88;
  --border: rgba(255, 255, 255, 0.10);
  --border-2: rgba(255, 255, 255, 0.16);
  --glass: rgba(255, 255, 255, 0.03);
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 12px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.30);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.45);
  --shadow-accent: 0 0 20px rgba(45, 212, 170, 0.35);
  --font: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
}
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  background-image:
    radial-gradient(900px 420px at -5% 0%, rgba(46,124,246,0.16), transparent 60%),
    radial-gradient(720px 460px at 105% 100%, rgba(45,212,160,0.10), transparent 60%),
    linear-gradient(rgba(255,255,255,0.028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.028) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 44px 44px, 44px 44px;
  background-attachment: fixed;
}
body.no-scroll { overflow: hidden; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, textarea { font-family: inherit; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
::selection { background: rgba(46, 124, 246, 0.35); color: #fff; }

/* 顶部信息条 */
.top-bar {
  background: #070D18;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  font-size: 13px;
  color: var(--text-2);
  position: relative;
  z-index: 120;
}
.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 34px;
  gap: 16px;
}
.topbar-domain { color: var(--text-2); font-weight: 600; letter-spacing: 0.02em; }
.topbar-msg { color: var(--text-3); display: flex; align-items: center; gap: 6px; white-space: nowrap; overflow: hidden; }
.topbar-msg .lock-icon { color: var(--accent); font-size: 14px; }
.topbar-action { color: var(--text-3); white-space: nowrap; }

/* 主导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 110;
  background: rgba(10, 17, 32, 0.72);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: 20px;
}
.brand { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.logo-mark { display: flex; align-items: center; justify-content: center; width: 38px; height: 38px; border-radius: 12px; background: rgba(46,124,246,0.12); border: 1px solid rgba(46,124,246,0.25); }
.logo-text {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(90deg, #E7EDF7, #b0c4e8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.main-nav { display: flex; align-items: center; gap: 28px; margin-left: auto; }
.main-nav a {
  font-size: 15px;
  color: var(--text-2);
  padding: 8px 2px;
  position: relative;
  transition: color 0.25s ease;
  letter-spacing: 0.02em;
}
.main-nav a:hover { color: var(--text); }
.main-nav a.active { color: #fff; font-weight: 600; }
.main-nav a.active::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  box-shadow: 0 0 8px rgba(45, 212, 170, 0.5);
}
.header-actions { display: flex; align-items: center; gap: 14px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 48px;
  padding: 0 24px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  transition: all 0.3s ease;
  border: 1px solid transparent;
  white-space: nowrap;
}
.btn-sm { height: 40px; padding: 0 18px; font-size: 14px; border-radius: 10px; }
.btn-primary {
  background: linear-gradient(135deg, #2E7CF6, #2DD4A0);
  color: #fff;
  box-shadow: var(--shadow-accent), 0 0 0 1px rgba(45,212,170,0.4);
}
.btn-primary:hover { filter: brightness(1.08); box-shadow: 0 0 30px rgba(45,212,170,0.5), 0 0 0 1px rgba(45,212,170,0.6); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(2px); filter: brightness(0.98); }
.btn-ghost { background: transparent; border-color: rgba(255, 255, 255, 0.25); color: var(--text); }
.btn-ghost:hover { border-color: rgba(255, 255, 255, 0.5); background: rgba(255, 255, 255, 0.06); }
.btn-lg { height: 56px; padding: 0 36px; font-size: 16px; border-radius: 14px; }
.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.03);
  transition: background 0.25s;
}
.menu-toggle:hover { background: rgba(255, 255, 255, 0.08); }
.menu-toggle .bar {
  width: 20px;
  height: 2px;
  background: var(--text);
  display: block;
  position: relative;
  border-radius: 2px;
  transition: background 0.2s;
}
.menu-toggle .bar::before,
.menu-toggle .bar::after {
  content: '';
  position: absolute;
  left: 0;
  width: 20px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s ease, top 0.3s ease;
}
.menu-toggle .bar::before { top: -7px; }
.menu-toggle .bar::after { top: 7px; }
.menu-toggle.active .bar { background: transparent; }
.menu-toggle.active .bar::before { top: 0; transform: rotate(45deg); }
.menu-toggle.active .bar::after { top: 0; transform: rotate(-45deg); }
.nav-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 105;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.nav-overlay.show { opacity: 1; visibility: visible; }

/* Hero */
.category-hero {
  position: relative;
  padding: 96px 0 88px;
  background: url('/assets/images/backpic/back-2.webp') center 30% / cover no-repeat;
}
.category-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10,17,32,0.72) 0%, rgba(10,17,32,0.92) 100%);
}
.hero-content { position: relative; z-index: 2; max-width: 760px; }
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--text-3);
  margin-bottom: 20px;
}
.breadcrumb a { color: var(--text-3); transition: color 0.25s; }
.breadcrumb a:hover { color: var(--primary-light); }
.breadcrumb .sep { color: rgba(255,255,255,0.25); }
.hero-title {
  font-size: clamp(28px, 4.5vw, 44px);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: 0.02em;
  margin-bottom: 18px;
}
.hero-title .grad {
  background: linear-gradient(90deg, #38BDF8, #2DD4A0);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-2);
  margin-bottom: 32px;
  max-width: 640px;
}
.hero-btns { display: flex; gap: 16px; flex-wrap: wrap; }

/* Section 通用 */
.section { padding: 96px 0; }
.section-alt { background: rgba(15, 26, 46, 0.45); border-top: 1px solid rgba(255, 255, 255, 0.05); border-bottom: 1px solid rgba(255, 255, 255, 0.05); }
.section-head { max-width: 720px; margin-bottom: 48px; }
.section-title {
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  letter-spacing: 0.02em;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}
.section-title::before {
  content: '';
  width: 4px;
  height: 24px;
  border-radius: 999px;
  background: linear-gradient(180deg, #2E7CF6, #2DD4A0);
  flex-shrink: 0;
}
.section-sub { color: var(--text-2); font-size: 16px; line-height: 1.8; }

/* 快速开始 */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.step-card {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px 24px 26px;
  position: relative;
  overflow: hidden;
  transition: transform 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
}
.step-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.28), transparent);
}
.step-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 24px;
  right: 24px;
  height: 1px;
  background: linear-gradient(90deg, rgba(46,124,246,0.4), rgba(45,212,160,0.4));
  opacity: 0;
  transition: opacity 0.35s;
}
.step-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgba(46,124,246,0.35); }
.step-card:hover::after { opacity: 1; }
.step-num { font-size: 13px; font-weight: 700; color: var(--accent); letter-spacing: 0.1em; display: flex; align-items: center; gap: 8px; }
.step-num::after { content: ''; width: 24px; height: 1px; background: rgba(45,212,170,0.35); }
.step-card h3 { font-size: 18px; font-weight: 600; margin: 14px 0 8px; line-height: 1.5; }
.step-card p { color: var(--text-2); font-size: 14px; line-height: 1.75; }

/* 核心操作指引 */
.guide-rows { display: grid; gap: 56px; }
.guide-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 56px;
}
.guide-media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  position: relative;
  background: var(--bg-2);
}
.guide-media::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04);
}
.guide-media img { width: 100%; height: 100%; object-fit: cover; }
.guide-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(46, 124, 246, 0.14);
  border: 1px solid rgba(46, 124, 246, 0.3);
  color: var(--primary-light);
  font-size: 13px;
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.guide-content h3 { font-size: 24px; font-weight: 700; margin-bottom: 12px; letter-spacing: 0.02em; }
.guide-content > p { color: var(--text-2); margin-bottom: 16px; }
.guide-content ul { margin-top: 8px; }
.guide-content ul li {
  padding-left: 26px;
  position: relative;
  margin-bottom: 8px;
  color: #b6c2d4;
  font-size: 15px;
}
.guide-content ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  box-shadow: 0 0 6px rgba(45, 212, 170, 0.5);
}

/* 安全与隐私 */
.security-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.security-card {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  position: relative;
  transition: transform 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
}
.security-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 24px;
  right: 24px;
  height: 1px;
  background: linear-gradient(90deg, rgba(255,255,255,0.15), transparent);
}
.security-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: rgba(45,212,170,0.35); }
.sec-icon {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(46, 124, 246, 0.14);
  border: 1px solid rgba(46, 124, 246, 0.28);
  margin-bottom: 18px;
  color: var(--primary-light);
}
.security-card h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.security-card p { color: var(--text-2); font-size: 14px; line-height: 1.75; }

/* 多端同步 */
.sync-panel {
  background: linear-gradient(135deg, rgba(46,124,246,0.10), rgba(45,212,160,0.06));
  border: 1px solid rgba(46, 124, 246, 0.22);
  border-radius: calc(var(--radius-lg) + 4px);
  padding: 56px;
  position: relative;
  overflow: hidden;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}
.sync-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(56, 189, 248, 0.6), transparent);
}
.sync-panel::after {
  content: '';
  position: absolute;
  right: -120px;
  top: -120px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(45, 212, 160, 0.14), transparent 65%);
  pointer-events: none;
}
.sync-copy h3 { font-size: 24px; font-weight: 700; margin-bottom: 14px; }
.sync-copy p { color: var(--text-2); margin-bottom: 20px; }
.sync-feats { display: grid; gap: 14px; }
.sync-feat {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: var(--radius-md);
  padding: 16px 18px;
}
.sync-feat .f-icon { flex-shrink: 0; color: var(--accent); margin-top: 2px; }
.sync-feat h4 { font-size: 15px; font-weight: 600; margin-bottom: 4px; }
.sync-feat p { color: var(--text-2); font-size: 14px; margin: 0; }
.sync-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 280px;
  border-radius: var(--radius-lg);
  background: rgba(10, 17, 32, 0.5);
  border: 1px dashed rgba(56, 189, 248, 0.3);
}
.device-stack { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.device-chip {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 20px 18px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-md);
  min-width: 90px;
}
.device-chip .d-icon { color: var(--primary-light); }
.device-chip span { font-size: 13px; color: var(--text-2); }

/* FAQ */
.faq-list { max-width: 860px; margin: 0 auto; display: grid; gap: 14px; }
.faq-item {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}
.faq-item.open { background: rgba(255, 255, 255, 0.05); border-color: rgba(46, 124, 246, 0.45); box-shadow: 0 4px 24px rgba(0, 0, 0, 0.2); }
.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  user-select: none;
  transition: color 0.2s;
}
.faq-q:hover { color: var(--primary-light); }
.faq-icon {
  width: 26px;
  height: 26px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  transition: transform 0.35s ease, background 0.3s, border-color 0.3s;
}
.faq-icon::before, .faq-icon::after { content: ''; position: absolute; background: var(--text-2); border-radius: 2px; transition: background 0.3s; }
.faq-icon::before { width: 10px; height: 2px; }
.faq-icon::after { width: 2px; height: 10px; }
.faq-item.open .faq-icon { transform: rotate(45deg); background: rgba(46, 124, 246, 0.22); border-color: rgba(46, 124, 246, 0.6); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  padding: 0 24px;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
  transition: max-height 0.38s ease, padding 0.38s ease;
}
.faq-item.open .faq-a { max-height: 420px; padding: 0 24px 22px; }

/* CTA 帮助 */
.help-section {
  position: relative;
  padding: 96px 0;
  background: url('/assets/images/backpic/back-3.png') center / cover no-repeat;
}
.help-section::before { content: ''; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(10,17,32,0.82), rgba(10,17,32,0.94)); }
.help-card {
  position: relative;
  z-index: 2;
  text-align: center;
  background: rgba(15, 26, 46, 0.62);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: calc(var(--radius-lg) + 4px);
  padding: 64px 40px;
  box-shadow: var(--shadow-lg);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}
.help-card h2 { font-size: clamp(24px, 3vw, 32px); font-weight: 700; margin-bottom: 14px; }
.help-card > p { color: var(--text-2); font-size: 16px; max-width: 560px; margin: 0 auto 32px; }
.help-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.help-note { margin-top: 20px; font-size: 13px; color: var(--text-3); }

/* 页脚 */
.site-footer { background: #070D18; border-top: 1px solid rgba(45, 212, 170, 0.2); box-shadow: 0 -1px 12px rgba(45, 212, 170, 0.06); }
.footer-main {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding: 64px 0 44px;
}
.footer-brand p { color: var(--text-3); font-size: 14px; margin-top: 14px; max-width: 300px; line-height: 1.8; }
.footer-col h4, .footer-contact h4 { color: var(--text); font-size: 15px; font-weight: 600; margin-bottom: 18px; letter-spacing: 0.04em; }
.footer-col li { margin-bottom: 11px; }
.footer-col a { color: var(--text-3); font-size: 14px; transition: color 0.25s, padding-left 0.25s; }
.footer-col a:hover { color: var(--primary-light); padding-left: 4px; }
.footer-contact p { color: var(--text-3); font-size: 14px; margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding: 20px 0;
  text-align: center;
  color: var(--text-3);
  font-size: 13px;
}

/* 滚动提示 */
.scroll-hint {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  color: var(--text-3);
  font-size: 12px;
  margin-top: 48px;
}
.scroll-hint .line {
  width: 1px;
  height: 36px;
  background: linear-gradient(180deg, transparent, rgba(148, 163, 188, 0.5));
  position: relative;
  overflow: hidden;
}
.scroll-hint .line::after {
  content: '';
  position: absolute;
  width: 1px;
  height: 8px;
  background: var(--accent);
  left: 0;
  top: -8px;
  animation: scrollDot 2.2s ease-in-out infinite;
}
@keyframes scrollDot { 0% { top: -8px; } 100% { top: 40px; } }

/* 响应式 */
@media (max-width: 1199px) {
  .steps-grid, .security-grid { grid-template-columns: repeat(2, 1fr); }
  .sync-panel { padding: 44px; gap: 32px; }
}
@media (max-width: 1024px) {
  .container { padding: 0 16px; }
  .menu-toggle { display: flex; }
  .header-actions .btn { display: none; }
  .main-nav {
    position: fixed;
    top: 0;
    right: 0;
    width: 300px;
    height: 100vh;
    background: rgba(10, 17, 32, 0.98);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    padding: 88px 28px 32px;
    gap: 4px;
    transform: translateX(100%);
    transition: transform 0.35s ease;
    box-shadow: -16px 0 48px rgba(0, 0, 0, 0.55);
    margin-left: 0;
    z-index: 130;
    border-left: 1px solid rgba(255, 255, 255, 0.08);
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav a {
    font-size: 16px;
    display: block;
    width: 100%;
    padding: 15px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--text-2);
  }
  .main-nav a:hover { color: var(--text); background: rgba(255,255,255,0.02); }
  .main-nav a.active { color: var(--accent); font-weight: 600; }
  .main-nav a.active::after { display: none; }
  .section { padding: 72px 0; }
  .guide-row { grid-template-columns: 1fr; gap: 28px; }
  .guide-media { order: 2; }
  .guide-row:nth-child(odd) .guide-media { order: 2; }
  .guide-row:nth-child(even) .guide-media { order: 2; }
  .sync-panel { grid-template-columns: 1fr; }
  .footer-main { grid-template-columns: 1fr 1fr; gap: 32px; }
  .category-hero { padding: 72px 0 64px; }
}
@media (max-width: 767px) {
  .topbar-msg { display: none; }
  .topbar-inner { justify-content: center; }
  .steps-grid, .security-grid { grid-template-columns: 1fr; }
  .hero-btns .btn { width: 100%; max-width: 100%; }
  .hero-btns { flex-direction: column; }
  .section { padding: 56px 0; }
  .section-head { margin-bottom: 32px; }
  .sync-panel { padding: 28px 20px; }
  .help-card { padding: 40px 20px; }
  .footer-main { grid-template-columns: 1fr; padding: 48px 0 36px; }
  .footer-contact p { font-size: 13px; }
  .scroll-hint { display: none; }
  .btn-lg { width: 100%; max-width: 100%; }
  .help-btns .btn { width: 100%; }
  .guide-content h3 { font-size: 20px; }
}
@media (max-width: 480px) {
  .header-inner { height: 64px; }
  .logo-text { font-size: 17px; }
  .hero-title { font-size: 26px; }
  .hero-desc { font-size: 15px; }
  .section-title { font-size: 20px; }
  .faq-q { font-size: 15px; padding: 18px 18px; }
  .faq-a { font-size: 14px; padding: 0 18px; }
  .faq-item.open .faq-a { padding: 0 18px 18px; }
  .step-card { padding: 24px 20px; }
  .security-card { padding: 24px 20px; }
}