/* ==========================================================================
   NanaZip 官方网站样式表
   扁平 · 现代 · 专业 · 蓝色品牌色
   ========================================================================== */

/* ---------- 设计令牌 ---------- */
:root {
  --brand: #0078D4;          /* 主品牌蓝 */
  --brand-dark: #005A9E;     /* 深蓝 */
  --brand-light: #2A9EF0;    /* 浅蓝 */
  --brand-50: #EFF6FC;       /* 极浅蓝背景 */
  --brand-100: #DEEAF5;
  --accent: #00B7FF;         /* 高亮蓝 */
  --navy: #002060;           /* 深海军蓝（logo色）*/

  --ink: #1A2233;            /* 主文字 */
  --ink-2: #4A5568;          /* 次文字 */
  --ink-3: #8A94A6;          /* 辅助文字 */
  --line: #E4EAF1;           /* 分割线 */
  --bg: #FFFFFF;
  --bg-soft: #F7F9FC;
  --bg-card: #FFFFFF;

  --success: #0EA968;
  --warning: #F5A623;

  --shadow-sm: 0 1px 3px rgba(16, 36, 64, .06), 0 1px 2px rgba(16, 36, 64, .04);
  --shadow-md: 0 4px 16px rgba(16, 36, 64, .08), 0 2px 6px rgba(16, 36, 64, .04);
  --shadow-lg: 0 18px 48px rgba(16, 36, 64, .12), 0 6px 18px rgba(16, 36, 64, .06);
  --shadow-brand: 0 12px 30px rgba(0, 120, 212, .28);

  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 22px;
  --radius-pill: 999px;

  --container: 1200px;
  --header-h: 68px;

  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
          "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  --font-mono: "Cascadia Code", "JetBrains Mono", "Consolas", "Courier New", monospace;
}

/* ---------- 重置 ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--brand); text-decoration: none; transition: color .2s; }
a:hover { color: var(--brand-dark); }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
h1, h2, h3, h4, h5 { line-height: 1.3; font-weight: 700; color: var(--ink); }

/* ---------- 容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}
.section { padding: 88px 0; }
.section-sm { padding: 56px 0; }
.section-tight { padding: 40px 0; }

/* ---------- 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-pill);
  transition: all .22s cubic-bezier(.4, 0, .2, 1);
  white-space: nowrap;
  cursor: pointer;
  border: 2px solid transparent;
}
.btn-primary {
  background: var(--brand);
  color: #fff;
  box-shadow: var(--shadow-brand);
}
.btn-primary:hover {
  background: var(--brand-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 16px 36px rgba(0, 120, 212, .36);
}
.btn-ghost {
  background: rgba(255,255,255,.12);
  color: #fff;
  border-color: rgba(255,255,255,.5);
  backdrop-filter: blur(6px);
}
.btn-ghost:hover { background: rgba(255,255,255,.22); color:#fff; }
.btn-outline {
  background: transparent;
  color: var(--brand);
  border-color: var(--brand);
}
.btn-outline:hover { background: var(--brand); color: #fff; }
.btn-lg { padding: 15px 34px; font-size: 16px; }
.btn-sm { padding: 8px 18px; font-size: 14px; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .85);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--line);
}
.nav {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 20px;
  color: var(--ink);
}
.brand img { width: 36px; height: 36px; }
.brand span { letter-spacing: -.3px; }
.brand .dot { color: var(--brand); }
.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
}
.nav-links a {
  color: var(--ink-2);
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  font-size: 15px;
  transition: all .2s;
}
.nav-links a:hover { color: var(--brand); background: var(--brand-50); }
.nav-links a.active { color: var(--brand); background: var(--brand-50); }
.nav-cta { display: flex; align-items: center; gap: 12px; }
.nav-toggle {
  display: none;
  width: 42px; height: 42px;
  border-radius: 10px;
  align-items: center; justify-content: center;
  color: var(--ink);
}
.nav-toggle svg { width: 24px; height: 24px; }

@media (max-width: 900px) {
  .nav-links {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    background: #fff;
    flex-direction: column;
    align-items: stretch;
    padding: 12px 16px 20px;
    gap: 4px;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-md);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: all .25s;
  }
  .nav-links.open { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 12px 16px; }
  .nav-toggle { display: inline-flex; }
  .nav-cta .btn-text { display: none; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  background:
    radial-gradient(1200px 500px at 80% -10%, rgba(42, 158, 240, .25), transparent 60%),
    radial-gradient(900px 480px at 0% 110%, rgba(0, 120, 212, .18), transparent 60%),
    linear-gradient(160deg, #002060 0%, #0050C0 45%, #0078D4 100%);
  color: #fff;
  padding: 96px 0 110px;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(900px 600px at 70% 0%, #000 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(900px 600px at 70% 0%, #000 30%, transparent 80%);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 1; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  gap: 56px;
  align-items: center;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,255,255,.12);
  border: 1px solid rgba(255,255,255,.25);
  color: #EAF4FF;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 22px;
  backdrop-filter: blur(8px);
}
.hero-badge .pulse {
  width: 8px; height: 8px; border-radius: 50%;
  background: #5BF0A0;
  box-shadow: 0 0 0 0 rgba(91, 240, 160, .6);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(91,240,160,.6); }
  70% { box-shadow: 0 0 0 8px rgba(91,240,160,0); }
  100% { box-shadow: 0 0 0 0 rgba(91,240,160,0); }
}
.hero h1 {
  font-size: 52px;
  line-height: 1.12;
  color: #fff;
  letter-spacing: -1px;
  margin-bottom: 22px;
}
.hero h1 .grad {
  background: linear-gradient(90deg, #8FD4FF 0%, #FFFFFF 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero p.lead {
  font-size: 18px;
  color: #DCEBFA;
  max-width: 560px;
  margin-bottom: 32px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-stats {
  display: flex;
  gap: 38px;
  margin-top: 44px;
  padding-top: 28px;
  border-top: 1px solid rgba(255,255,255,.15);
}
.hero-stat .num { font-size: 30px; font-weight: 800; color: #fff; letter-spacing: -.5px; }
.hero-stat .lbl { font-size: 13px; color: #BFD9F5; margin-top: 2px; }

/* Hero visual: app window mockup */
.hero-visual {
  position: relative;
}
.app-mock {
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 30px 80px rgba(0,0,0,.35), 0 8px 24px rgba(0,0,0,.2);
  overflow: hidden;
  transform: perspective(1200px) rotateY(-6deg) rotateX(3deg);
  border: 1px solid rgba(255,255,255,.3);
}
.app-titlebar {
  height: 38px;
  background: linear-gradient(180deg, #F3F6FA, #E8EEF5);
  display: flex; align-items: center;
  padding: 0 14px;
  border-bottom: 1px solid #E1E7EF;
  gap: 7px;
}
.app-titlebar .dot { width: 11px; height: 11px; border-radius: 50%; }
.app-titlebar .d1 { background: #FF6058; }
.app-titlebar .d2 { background: #FFBC2C; }
.app-titlebar .d3 { background: #28C840; }
.app-titlebar .ttl { margin-left: 12px; font-size: 12px; color: #6b7280; font-weight: 500; }
.app-toolbar {
  display: flex;
  gap: 6px;
  padding: 10px 14px;
  background: #FAFBFC;
  border-bottom: 1px solid #EEF2F7;
}
.app-toolbar .tb {
  padding: 5px 12px;
  font-size: 12px;
  border-radius: 6px;
  background: #fff;
  border: 1px solid #E1E7EF;
  color: #4a5568;
}
.app-toolbar .tb.active { background: var(--brand); color: #fff; border-color: var(--brand); }
.app-body {
  display: grid;
  grid-template-columns: 160px 1fr;
  min-height: 320px;
}
.app-side {
  background: #F5F8FC;
  padding: 14px 10px;
  border-right: 1px solid #EEF2F7;
  font-size: 12.5px;
}
.app-side .grp { color: #8a94a6; font-size: 11px; text-transform: uppercase; letter-spacing: .5px; margin: 10px 6px 6px; }
.app-side .item { padding: 7px 10px; border-radius: 6px; color: #4a5568; cursor: default; }
.app-side .item.active { background: var(--brand); color: #fff; }
.app-side .item.active::before { content: "📁 "; }
.app-side .item::before { content: "📂 "; opacity: .8; }
.app-main { padding: 14px 16px; background: #fff; }
.app-row {
  display: grid;
  grid-template-columns: 24px 1fr 80px 90px 110px;
  gap: 10px;
  align-items: center;
  padding: 7px 6px;
  font-size: 12.5px;
  border-bottom: 1px solid #F1F4F8;
  color: #3a4452;
}
.app-row.head { color: #8a94a6; font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: .5px; }
.app-row .ic { font-size: 14px; }
.app-row .bar { height: 6px; background: #EEF2F7; border-radius: 3px; overflow: hidden; }
.app-row .bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--brand), var(--brand-light)); border-radius: 3px; }
.app-statusbar {
  padding: 7px 14px;
  background: #FAFBFC;
  border-top: 1px solid #EEF2F7;
  font-size: 11.5px;
  color: #8a94a6;
  display: flex; justify-content: space-between;
}

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .hero h1 { font-size: 36px; }
  .hero p.lead { font-size: 16px; }
  .hero-stats { gap: 24px; flex-wrap: wrap; }
  .app-mock { transform: none; }
}

/* ---------- 通用区块标题 ---------- */
.sec-head { text-align: center; max-width: 760px; margin: 0 auto 52px; }
.sec-head .tag {
  display: inline-block;
  color: var(--brand);
  font-weight: 700;
  letter-spacing: 1px;
  font-size: 13px;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.sec-head h2 {
  font-size: 38px;
  letter-spacing: -.5px;
  margin-bottom: 14px;
}
.sec-head p {
  color: var(--ink-2);
  font-size: 17px;
}
@media (max-width: 760px) {
  .sec-head h2 { font-size: 28px; }
  .sec-head p { font-size: 15px; }
}

/* ---------- 特性卡片 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 30px 26px;
  transition: all .25s;
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--brand-100);
}
.feature-icon {
  width: 52px; height: 52px;
  border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--brand-50), var(--brand-100));
  color: var(--brand);
  margin-bottom: 18px;
}
.feature-icon svg { width: 28px; height: 28px; }
.feature-card h3 { font-size: 19px; margin-bottom: 10px; }
.feature-card p { color: var(--ink-2); font-size: 15px; }
@media (max-width: 900px) { .feature-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 620px) { .feature-grid { grid-template-columns: 1fr; } }

/* ---------- 使用场景 ---------- */
.scenarios {
  background: var(--bg-soft);
}
.scenario-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
}
.scenario-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px;
  display: flex;
  gap: 22px;
  border: 1px solid var(--line);
  transition: all .25s;
}
.scenario-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--brand-100);
  transform: translateY(-2px);
}
.scenario-emoji {
  flex-shrink: 0;
  width: 58px; height: 58px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px;
  background: linear-gradient(135deg, var(--brand-50), #E8F1FB);
}
.scenario-card h3 { font-size: 19px; margin-bottom: 8px; }
.scenario-card p { color: var(--ink-2); font-size: 15px; }
.scenario-card .tag {
  display: inline-block;
  margin-top: 12px;
  font-size: 12px;
  color: var(--brand);
  background: var(--brand-50);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  font-weight: 600;
}
@media (max-width: 760px) { .scenario-grid { grid-template-columns: 1fr; } }

/* ---------- 用户评价 ---------- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.review-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 28px 26px;
  position: relative;
  transition: all .25s;
}
.review-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.review-quote {
  font-size: 56px;
  color: var(--brand-100);
  font-family: Georgia, serif;
  line-height: .6;
  position: absolute;
  top: 22px; right: 24px;
}
.review-stars { color: #F5A623; font-size: 16px; margin-bottom: 12px; letter-spacing: 2px; }
.review-text { color: var(--ink); font-size: 15px; line-height: 1.75; margin-bottom: 18px; }
.review-user { display: flex; align-items: center; gap: 12px; }
.review-avatar {
  width: 44px; height: 44px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; color: #fff; font-size: 16px;
}
.review-name { font-weight: 700; font-size: 14px; }
.review-meta { font-size: 12px; color: var(--ink-3); }
@media (max-width: 900px) { .reviews-grid { grid-template-columns: 1fr; } }

/* ---------- 下载 CTA 横幅 ---------- */
.cta-band {
  background:
    radial-gradient(700px 300px at 90% 10%, rgba(42,158,240,.4), transparent 60%),
    linear-gradient(135deg, var(--navy), var(--brand));
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 56px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
  flex-wrap: wrap;
  box-shadow: var(--shadow-lg);
}
.cta-band h2 { color: #fff; font-size: 30px; margin-bottom: 8px; }
.cta-band p { color: #DCEBFA; font-size: 16px; }
@media (max-width: 760px) { .cta-band { padding: 36px 26px; } .cta-band h2 { font-size: 24px; } }

/* ---------- 下载中心 ---------- */
.dl-hero {
  background: linear-gradient(160deg, var(--navy), var(--brand));
  color: #fff;
  padding: 70px 0 90px;
  text-align: center;
}
.dl-hero h1 { color: #fff; font-size: 42px; margin-bottom: 14px; letter-spacing: -.5px; }
.dl-hero p { color: #DCEBFA; font-size: 17px; max-width: 640px; margin: 0 auto; }

.dl-options {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
/*  margin-top: -60px; */
  position: relative;
  z-index: 2;
}
.dl-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  transition: all .25s;
  text-align: center;
}
.dl-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.dl-card.recommended { border: 2px solid var(--brand); position: relative; }
.dl-card.recommended::before {
  content: "推荐";
  position: absolute;
  top: -12px; left: 50%;
  transform: translateX(-50%);
  background: var(--brand);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
}
.dl-logo {
  width: 64px; height: 64px;
  margin: 0 auto 16px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  font-size: 30px;
}
.dl-logo.ms { background: linear-gradient(135deg, #0078D4, #005A9E); color: #fff; }
.dl-logo.gh { background: linear-gradient(135deg, #24292E, #1A1E22); color: #fff; }
.dl-logo.sf { background: linear-gradient(135deg, #FF6600, #CC5200); color: #fff; }
.dl-card h3 { font-size: 20px; margin-bottom: 6px; }
.dl-card .sub { color: var(--ink-3); font-size: 13px; margin-bottom: 16px; }
.dl-card .meta { font-size: 13px; color: var(--ink-2); margin-bottom: 20px; padding: 10px; background: var(--bg-soft); border-radius: var(--radius-sm); }
@media (max-width: 900px) { .dl-options { grid-template-columns: 1fr; } }

/* 系统需求 + 安装指引 */
.dl-info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}
.info-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 32px;
}
.info-card h3 { font-size: 20px; margin-bottom: 18px; display: flex; align-items: center; gap: 10px; }
.info-card h3 .ic { color: var(--brand); }
.info-list { display: flex; flex-direction: column; gap: 12px; }
.info-list li {
  display: flex; gap: 10px;
  padding: 10px 14px;
  background: var(--bg-soft);
  border-radius: var(--radius-sm);
  font-size: 14.5px;
}
.info-list li .k { color: var(--ink-3); min-width: 100px; flex-shrink: 0; }
.info-list li .v { color: var(--ink); font-weight: 500; }
@media (max-width: 900px) { .dl-info-grid { grid-template-columns: 1fr; } }

/* 步骤 */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  counter-reset: step;
}
.step-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 30px 26px;
  position: relative;
}
.step-card .num {
  counter-increment: step;
  width: 40px; height: 40px;
  border-radius: 12px;
  background: var(--brand);
  color: #fff;
  font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 16px;
  font-size: 18px;
}
.step-card .num::before { content: counter(step); }
.step-card h4 { font-size: 17px; margin-bottom: 8px; }
.step-card p { color: var(--ink-2); font-size: 14.5px; }
@media (max-width: 900px) { .steps { grid-template-columns: 1fr; } }

/* 版本历史 */
.version-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--line);
}
.version-table th, .version-table td {
  padding: 14px 20px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
}
.version-table th {
  background: var(--bg-soft);
  font-weight: 700;
  color: var(--ink);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: .5px;
}
.version-table tr:last-child td { border-bottom: none; }
.version-table tr:hover { background: var(--brand-50); }
.version-table .badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
}
.badge.stable { background: #E6F6EF; color: var(--success); }
.badge.preview { background: #FFF4E0; color: var(--warning); }

/* ---------- 功能页 ---------- */
.page-hero {
  background:
    radial-gradient(900px 400px at 80% 0%, rgba(42,158,240,.18), transparent 60%),
    linear-gradient(160deg, var(--navy), var(--brand));
  color: #fff;
  padding: 72px 0 84px;
  text-align: center;
}
.page-hero h1 { color: #fff; font-size: 40px; margin-bottom: 12px; letter-spacing: -.5px; }
.page-hero p { color: #DCEBFA; font-size: 17px; max-width: 680px; margin: 0 auto; }
.breadcrumb {
  display: flex; justify-content: center; gap: 8px;
  color: #BFD9F5; font-size: 13px; margin-bottom: 18px;
}
.breadcrumb a { color: #BFD9F5; }
.breadcrumb a:hover { color: #fff; }

/* 功能分组 */
.feat-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 50px;
  align-items: center;
  padding: 56px 0;
}
.feat-block:nth-child(even) .feat-text { order: 2; }
.feat-block .feat-text h2 { font-size: 30px; margin-bottom: 16px; letter-spacing: -.3px; }
.feat-block .feat-text p { color: var(--ink-2); font-size: 16px; margin-bottom: 18px; }
.feat-block .feat-text ul.checks li {
  padding: 8px 0 8px 30px;
  position: relative;
  color: var(--ink-2);
  font-size: 15px;
}
.feat-block .feat-text ul.checks li::before {
  content: "";
  position: absolute; left: 0; top: 12px;
  width: 18px; height: 18px;
  background: var(--brand);
  border-radius: 50%;
  -webkit-mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M9 16.2l-3.5-3.5L4 14.2 9 19.2 20 8.2l-1.5-1.5z' fill='white'/></svg>") center/14px no-repeat;
          mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M9 16.2l-3.5-3.5L4 14.2 9 19.2 20 8.2l-1.5-1.5z' fill='white'/></svg>") center/14px no-repeat;
}
.feat-visual {
  background: linear-gradient(135deg, var(--brand-50), #E8F1FB);
  border-radius: var(--radius-lg);
  padding: 36px;
  min-height: 280px;
  display: flex; align-items: center; justify-content: center;
  position: relative;
  overflow: hidden;
}
.feat-visual .icon-big {
  font-size: 96px;
  filter: drop-shadow(0 8px 16px rgba(0,120,212,.25));
}
@media (max-width: 860px) {
  .feat-block { grid-template-columns: 1fr; gap: 28px; }
  .feat-block:nth-child(even) .feat-text { order: 0; }
}

/* 格式支持表 */
.format-table {
  width: 100%;
  background: #fff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  overflow: hidden;
}
.format-table th, .format-table td {
  padding: 12px 18px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}
.format-table th { background: var(--bg-soft); font-weight: 700; font-size: 13px; }
.format-table .fmt { font-family: var(--font-mono); color: var(--brand); font-weight: 600; }
.yes { color: var(--success); font-weight: 700; }
.no { color: var(--ink-3); }

/* ---------- 关于页 ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 50px;
  align-items: start;
}
.about-text p { color: var(--ink-2); margin-bottom: 16px; font-size: 16px; }
.about-side .info-card { margin-bottom: 22px; }
.stat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}
.stat-card {
  text-align: center;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 18px;
}
.stat-card .num { font-size: 32px; font-weight: 800; color: var(--brand); letter-spacing: -.5px; }
.stat-card .lbl { font-size: 13px; color: var(--ink-3); margin-top: 4px; }
@media (max-width: 760px) {
  .about-grid { grid-template-columns: 1fr; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
}

/* 时间线 */
.timeline { position: relative; padding-left: 30px; }
.timeline::before {
  content: ""; position: absolute;
  left: 8px; top: 6px; bottom: 6px;
  width: 2px; background: var(--brand-100);
}
.timeline-item { position: relative; padding-bottom: 26px; }
.timeline-item::before {
  content: ""; position: absolute;
  left: -30px; top: 4px;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: var(--brand);
  border: 3px solid #fff;
  box-shadow: 0 0 0 2px var(--brand-100);
}
.timeline-item .date { font-size: 13px; color: var(--brand); font-weight: 700; }
.timeline-item h4 { font-size: 17px; margin: 4px 0 6px; }
.timeline-item p { color: var(--ink-2); font-size: 14.5px; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 820px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 14px;
  overflow: hidden;
  transition: all .2s;
}
.faq-item:hover { border-color: var(--brand-100); }
.faq-q {
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.faq-q .arrow {
  flex-shrink: 0;
  width: 24px; height: 24px;
  display: flex; align-items: center; justify-content: center;
  color: var(--brand);
  transition: transform .25s;
}
.faq-item.open .faq-q .arrow { transform: rotate(180deg); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height .3s ease, padding .3s ease;
  padding: 0 24px;
  color: var(--ink-2);
  font-size: 15px;
  line-height: 1.75;
}
.faq-item.open .faq-a { max-height: 600px; padding: 0 24px 22px; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: #0B1B33;
  color: #B8C5DA;
  padding: 64px 0 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 44px;
}
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 16px; color: #fff; font-weight: 800; font-size: 20px; }
.footer-brand img { width: 36px; height: 36px; }
.footer-about { font-size: 14px; line-height: 1.75; color: #9AAAC4; max-width: 320px; }
.footer-col h4 { color: #fff; font-size: 14px; margin-bottom: 16px; letter-spacing: .5px; text-transform: uppercase; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { color: #9AAAC4; font-size: 14px; transition: color .2s; }
.footer-col ul li a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding-top: 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: #7A8AA8;
}
.footer-bottom a { color: #7A8AA8; }
.footer-bottom a:hover { color: #fff; }
@media (max-width: 760px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
  .footer-brand-col { grid-column: 1 / -1; }
}

/* ---------- 下载弹窗 ---------- */
.modal-mask {
  position: fixed;
  inset: 0;
  background: rgba(11, 27, 51, .55);
  backdrop-filter: blur(6px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 20px;
  opacity: 0;
  transition: opacity .25s;
}
.modal-mask.open { display: flex; opacity: 1; }
.modal {
  background: #fff;
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 760px;
  max-height: 92vh;
  overflow: auto;
  box-shadow: var(--shadow-lg);
  transform: scale(.96) translateY(8px);
  transition: transform .25s cubic-bezier(.4,0,.2,1);
}
.modal-mask.open .modal { transform: scale(1) translateY(0); }
.modal-head {
  padding: 24px 28px 16px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  background: linear-gradient(135deg, var(--brand-50), #fff);
}
.modal-head .ttl { display: flex; align-items: center; gap: 12px; }
.modal-head .ttl .ic {
  width: 44px; height: 44px;
  border-radius: 12px;
  background: var(--brand);
  color: #fff;
  display: flex; align-items: center; justify-content: center;
}
.modal-head h3 { font-size: 20px; }
.modal-head .sub { font-size: 13px; color: var(--ink-3); }
.modal-close {
  width: 38px; height: 38px;
  border-radius: 10px;
  color: var(--ink-2);
  display: flex; align-items: center; justify-content: center;
  transition: all .2s;
}
.modal-close:hover { background: var(--bg-soft); color: var(--ink); }
.modal-body { padding: 26px 28px 28px; }
.modal-body .intro { color: var(--ink-2); font-size: 15px; margin-bottom: 22px; line-height: 1.75; }

.qr-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-bottom: 24px;
}
.qr-card {
  border: 2px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  transition: all .2s;
}
.qr-card:hover { border-color: var(--brand); box-shadow: var(--shadow-sm); }
.qr-card img {
  width: 180px; height: 180px;
  margin: 0 auto 12px;
  border-radius: var(--radius-sm);
  background: #fff;
}
.qr-card .platform { font-weight: 700; font-size: 15px; margin-bottom: 4px; color: var(--ink); }
.qr-card .hint { font-size: 12px; color: var(--ink-3); }

.modal-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  align-items: center;
  justify-content: space-between;
}
.modal-actions .left { display: flex; gap: 10px; flex-wrap: wrap; }
.modal-actions .right { font-size: 13px; color: var(--ink-3); }
@media (max-width: 560px) {
  .qr-row { grid-template-columns: 1fr; }
  .qr-card img { width: 160px; height: 160px; }
}

/* ---------- 工具类 ---------- */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.bg-soft { background: var(--bg-soft); }
.eyebrow {
  display: inline-block;
  color: var(--brand);
  font-weight: 700;
  letter-spacing: 1.2px;
  font-size: 12px;
  text-transform: uppercase;
  margin-bottom: 10px;
}
.divider { height: 1px; background: var(--line); margin: 40px 0; border: 0; }

/* 滚动渐入 */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* 回到顶部 */
.to-top {
  position: fixed;
  right: 24px; bottom: 24px;
  width: 46px; height: 46px;
  border-radius: 50%;
  background: var(--brand);
  color: #fff;
  display: flex; align-items: center; justify-content: center;
  box-shadow: var(--shadow-brand);
  opacity: 0;
  pointer-events: none;
  transition: all .25s;
  z-index: 80;
}
.to-top.show { opacity: 1; pointer-events: auto; }
.to-top:hover { background: var(--brand-dark); transform: translateY(-2px); }