/* ============================================================
   Aegisub 中文站 · www.aegisub.com.cn
   设计系统：扁平现代专业 · 深蓝主色（源自官方 Logo）
   ============================================================ */

:root {
  /* 品牌色（取自 logo 深蓝） */
  --c-primary: #1B4E8A;
  --c-primary-dark: #143A66;
  --c-primary-darker: #0F2C4E;
  --c-primary-light: #2E6DB4;
  --c-primary-lighter: #4A85C6;

  /* 辅助色 */
  --c-accent: #2AA198;          /* 青绿，用于点缀/成功 */
  --c-accent-dark: #1F7B73;
  --c-warn: #C0662A;

  /* 中性色 */
  --c-ink: #1E2A38;
  --c-ink-soft: #43536A;
  --c-ink-mute: #6C7A8F;
  --c-line: #E2E8F0;
  --c-line-strong: #CBD5E1;
  --c-bg: #F5F7FA;
  --c-bg-white: #FFFFFF;
  --c-bg-soft: #EEF2F7;
  --c-primary-soft: #E8F0F9;

  /* 语义色 */
  --c-danger: #B54248;

  /* 排版 */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;

  /* 布局 */
  --wrap: 1120px;
  --radius: 10px;
  --radius-lg: 14px;
  --shadow-sm: 0 1px 3px rgba(15, 44, 78, 0.08);
  --shadow-md: 0 4px 14px rgba(15, 44, 78, 0.10);
  --shadow-lg: 0 12px 36px rgba(15, 44, 78, 0.18);
}

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

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

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-ink);
  background: var(--c-bg);
  min-height: 100vh;
}

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

a { color: var(--c-primary); text-decoration: none; }
a:hover { color: var(--c-primary-dark); text-decoration: underline; }

ul, ol { padding-left: 1.4em; }

:focus-visible {
  outline: 3px solid var(--c-primary-light);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--c-primary); color: #fff;
  padding: 10px 18px; border-radius: 0 0 8px 0; z-index: 200;
}
.skip-link:focus { left: 0; color: #fff; }

/* ============ 布局容器 ============ */
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }

.section { padding: 72px 0; }
.section-alt { background: var(--c-bg-white); }
.section-soft { background: var(--c-bg-soft); }

.section-head { text-align: center; max-width: 760px; margin: 0 auto 48px; }
.section-kicker {
  display: inline-block;
  font-size: 13px; font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--c-primary);
  background: var(--c-primary-soft);
  border-radius: 999px;
  padding: 4px 16px;
  margin-bottom: 14px;
}
.section-title { font-size: 32px; font-weight: 800; line-height: 1.3; color: var(--c-ink); }
.section-desc { margin-top: 12px; color: var(--c-ink-soft); font-size: 17px; }

/* ============ 顶部导航 ============ */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid var(--c-line);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 66px; gap: 28px;
}
.brand { display: flex; align-items: center; gap: 11px; flex-shrink: 0; }
.brand img { width: 136px; }
.brand-name { font-size: 21px; font-weight: 800; color: var(--c-ink); letter-spacing: 0.2px; }
.brand-name small { font-weight: 500; color: var(--c-ink-mute); font-size: 12px; display: block; line-height: 1; margin-top: 1px; }

.main-nav { display: flex; gap: 6px; flex: 1; justify-content: center; }
.main-nav a {
  padding: 8px 15px; border-radius: 8px;
  font-size: 15px; font-weight: 600; color: var(--c-ink-soft);
}
.main-nav a:hover { background: var(--c-primary-soft); color: var(--c-primary); text-decoration: none; }
.main-nav a[aria-current="page"] { background: var(--c-primary); color: #fff; }

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

.nav-toggle {
  display: none;
  background: none; border: 1px solid var(--c-line-strong); border-radius: 8px;
  padding: 8px 12px; cursor: pointer; color: var(--c-ink);
}

/* ============ 按钮 ============ */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  padding: 12px 26px;
  border-radius: 9px;
  font-size: 16px; font-weight: 700;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
  font-family: inherit;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--c-primary); color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { background: var(--c-primary-dark); color: #fff; }

.btn-accent {
  background: var(--c-accent); color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-accent:hover { background: var(--c-accent-dark); color: #fff; }

.btn-ghost {
  background: transparent; color: var(--c-primary);
  border-color: var(--c-line-strong);
}
.btn-ghost:hover { border-color: var(--c-primary); background: var(--c-primary-soft); }

.btn-lg { padding: 15px 34px; font-size: 17px; border-radius: 11px; }
.btn-sm { padding: 7px 16px; font-size: 14px; border-radius: 7px; }

/* 下载按钮（弹窗触发） */
.js-open-download {
  background: var(--c-primary); color: #fff;
  box-shadow: var(--shadow-sm);
}
.js-open-download:hover { background: var(--c-primary-dark); color: #fff; }
.js-open-download .dl-arrow { flex-shrink: 0; }

/* ============ 面包屑 ============ */
.breadcrumb { font-size: 13.5px; color: var(--c-ink-mute); padding: 18px 0 0; }
.breadcrumb ol { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 6px; }
.breadcrumb li+li::before { content: "/"; margin-right: 6px; color: var(--c-line-strong); }
.breadcrumb a { color: var(--c-ink-mute); }
.breadcrumb a:hover { color: var(--c-primary); }
.breadcrumb [aria-current] { color: var(--c-ink-soft); }

/* ============ 页头 Hero ============ */
.hero {
  background:
    radial-gradient(1100px 480px at 85% -10%, rgba(46, 109, 180, 0.16), transparent 62%),
    radial-gradient(900px 420px at -8% 8%, rgba(42, 161, 152, 0.10), transparent 58%),
    linear-gradient(180deg, #FFFFFF 0%, #F0F4F9 100%);
  padding: 84px 0 88px;
  overflow: hidden;
}
.hero-grid {
  display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 56px; align-items: center;
}
.hero-kicker {
  display: inline-flex; align-items: center; gap: 8px;
  background: #fff; border: 1px solid var(--c-line);
  border-radius: 999px; padding: 6px 16px;
  font-size: 13.5px; font-weight: 600; color: var(--c-ink-soft);
  box-shadow: var(--shadow-sm);
  margin-bottom: 22px;
}
.hero-kicker .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--c-accent);
}
.hero-title { font-size: 44px; font-weight: 800; line-height: 1.22; letter-spacing: 0.2px; color: var(--c-ink); }
.hero-title .brand-blue { color: var(--c-primary); }
.hero-sub { margin-top: 18px; font-size: 18px; color: var(--c-ink-soft); max-width: 560px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 10px 26px; margin-top: 26px; font-size: 14px; color: var(--c-ink-mute); }
.hero-meta li { list-style: none; display: inline-flex; align-items: center; gap: 7px; }
.hero-meta .check { color: var(--c-accent-dark); font-weight: 800; }

/* Hero 视觉区：界面示意图 */
.hero-visual { position: relative; }
.mock-window {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
.mock-titlebar {
  display: flex; align-items: center; gap: 8px;
  background: var(--c-bg-soft);
  border-bottom: 1px solid var(--c-line);
  padding: 10px 14px;
}
.mock-dot { width: 11px; height: 11px; border-radius: 50%; background: var(--c-line-strong); }
.mock-dot.r { background: #E08E8E; }
.mock-dot.y { background: #E5C36B; }
.mock-dot.g { background: #9BC49B; }
.mock-title { font-size: 12px; color: var(--c-ink-mute); margin-left: 6px; font-family: var(--font-mono); }

.mock-body { padding: 18px; display: grid; gap: 14px; }
.mock-video {
  aspect-ratio: 16 / 8.2;
  background:
    linear-gradient(135deg, #10365E 0%, #1B4E8A 55%, #2E6DB4 100%);
  border-radius: 8px;
  position: relative;
  overflow: hidden;
}
.mock-video .sub-line {
  position: absolute; left: 50%; transform: translateX(-50%);
  color: #fff; font-weight: 700; text-shadow: 0 0 6px rgba(0,0,0,0.6);
  white-space: nowrap;
}
.mock-video .sub-1 { top: 34%; font-size: 15px; letter-spacing: 2px; }
.mock-video .sub-2 { top: 56%; font-size: 19px; }
.mock-video .sub-2 em { font-style: normal; color: #FFE9A8; }
.mock-video .badge {
  position: absolute; top: 10px; right: 12px;
  font-size: 10.5px; font-family: var(--font-mono);
  color: rgba(255,255,255,0.85);
  background: rgba(0,0,0,0.28);
  border-radius: 4px; padding: 2px 7px;
}

.mock-audio {
  border: 1px solid var(--c-line); border-radius: 8px;
  background:
    repeating-linear-gradient(180deg, rgba(27,78,138,0.10) 0 2px, transparent 2px 9px),
    #FAFBFD;
  height: 74px; position: relative; overflow: hidden;
}
.mock-audio .wave {
  position: absolute; inset: 0;
  background:
    repeating-linear-gradient(90deg, transparent 0 5px, rgba(27,78,138,0.55) 5px 7px, transparent 7px 14px);
  mask-image: linear-gradient(90deg, transparent, #000 18%, #000 82%, transparent);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 18%, #000 82%, transparent);
  opacity: 0.55;
}
.mock-audio .sel {
  position: absolute; top: 6px; bottom: 6px; left: 42%; width: 30%;
  border-left: 2px solid var(--c-primary);
  border-right: 2px solid var(--c-primary);
  background: rgba(46,109,180,0.14);
}

.mock-grid { font-family: var(--font-mono); font-size: 11.5px; color: var(--c-ink-soft); }
.mock-grid .row {
  display: grid; grid-template-columns: 58px 74px 1fr 58px;
  border-bottom: 1px solid var(--c-line); padding: 5px 8px; gap: 8px;
  align-items: center;
}
.mock-grid .row.head { color: var(--c-ink-mute); font-weight: 700; background: var(--c-bg-soft); }
.mock-grid .row.active { background: var(--c-primary-soft); color: var(--c-primary-dark); font-weight: 700; }
.mock-grid .num { text-align: right; }

/* ============ 数据条 ============ */
.stats-band { background: var(--c-primary-darker); color: #fff; }
.stats-band .wrap {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
  padding-top: 34px; padding-bottom: 34px;
}
.stat-item { text-align: center; padding: 6px 10px; }
.stat-num { font-size: 30px; font-weight: 800; font-variant-numeric: tabular-nums; }
.stat-num .unit { font-size: 15px; font-weight: 600; color: rgba(255,255,255,0.75); margin-left: 2px; }
.stat-label { font-size: 13.5px; color: rgba(255,255,255,0.72); margin-top: 3px; }

/* ============ 卡片与网格 ============ */
.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--c-bg-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 26px;
  box-shadow: var(--shadow-sm);
}
.card:hover { box-shadow: var(--shadow-md); }
.card h3 { font-size: 18px; font-weight: 700; color: var(--c-ink); }
.card p { margin-top: 8px; font-size: 15px; color: var(--c-ink-soft); }

.feature-card .icon-box {
  width: 46px; height: 46px; border-radius: 11px;
  background: var(--c-primary-soft);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 16px;
  color: var(--c-primary);
}

/* ============ 场景卡 ============ */
.scene-card { position: relative; overflow: hidden; }
.scene-card .scene-tag {
  display: inline-block;
  font-size: 12px; font-weight: 700; letter-spacing: 0.08em;
  color: var(--c-accent-dark);
  background: rgba(42, 161, 152, 0.12);
  border-radius: 6px; padding: 3px 10px; margin-bottom: 12px;
}
.scene-card h3 { font-size: 18px; }
.scene-card ul { margin-top: 10px; }
.scene-card li { font-size: 14.5px; color: var(--c-ink-soft); margin-top: 6px; }

/* ============ 步骤条 ============ */
.steps { counter-reset: step; display: grid; gap: 22px; }
.step-card { position: relative; padding-left: 66px; }
.step-card::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute; left: 0; top: 2px;
  width: 46px; height: 46px; border-radius: 12px;
  background: var(--c-primary); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 16px;
  font-variant-numeric: tabular-nums;
}
.step-card h3 { font-size: 17px; font-weight: 700; }
.step-card p { margin-top: 6px; font-size: 15px; color: var(--c-ink-soft); }
.step-card .kbd-note { font-size: 13.5px; color: var(--c-ink-mute); margin-top: 6px; }

/* ============ 表格 ============ */
.table-wrap { overflow-x: auto; border: 1px solid var(--c-line); border-radius: var(--radius-lg); background: #fff; box-shadow: var(--shadow-sm); }
table.table { width: 100%; border-collapse: collapse; font-size: 14.5px; min-width: 640px; }
.table th {
  text-align: left; font-size: 13px; letter-spacing: 0.06em;
  color: var(--c-ink-mute); font-weight: 700;
  background: var(--c-bg-soft);
  padding: 12px 18px; border-bottom: 1px solid var(--c-line);
  white-space: nowrap;
}
.table td { padding: 13px 18px; border-bottom: 1px solid var(--c-line); vertical-align: top; }
.table tbody tr:last-child td { border-bottom: none; }
.table .mono { font-family: var(--font-mono); font-size: 13px; }
.table .ver { font-weight: 700; color: var(--c-ink); white-space: nowrap; }
.badge {
  display: inline-block; font-size: 12px; font-weight: 700;
  border-radius: 6px; padding: 2px 9px; white-space: nowrap;
}
.badge-latest { background: rgba(42,161,152,0.14); color: var(--c-accent-dark); }
.badge-beta { background: rgba(192,102,42,0.12); color: var(--c-warn); }
.badge-stable { background: var(--c-primary-soft); color: var(--c-primary); }
.badge-classic { background: var(--c-bg-soft); color: var(--c-ink-mute); }

/* ============ 提示框 ============ */
.note {
  border: 1px solid var(--c-line);
  border-left: 4px solid var(--c-primary);
  background: #fff;
  border-radius: 10px;
  padding: 16px 20px;
  font-size: 14.5px; color: var(--c-ink-soft);
  margin-top: 22px;
}
.note strong { color: var(--c-ink); }
.note.green { border-left-color: var(--c-accent); }
.note.orange { border-left-color: var(--c-warn); }

/* ============ 时间线（关于页） ============ */
.timeline { position: relative; padding-left: 30px; }
.timeline::before {
  content: ""; position: absolute; left: 8px; top: 6px; bottom: 6px;
  width: 2px; background: var(--c-line-strong); border-radius: 2px;
}
.timeline-item { position: relative; padding: 0 0 30px 24px; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
  content: ""; position: absolute; left: -30px; top: 7px;
  width: 14px; height: 14px; border-radius: 50%;
  background: #fff; border: 3px solid var(--c-primary);
}
.timeline-item.major::before { background: var(--c-primary); }
.timeline-time { font-size: 13px; font-weight: 700; color: var(--c-primary); letter-spacing: 0.04em; }
.timeline-item h3 { font-size: 17px; font-weight: 700; margin-top: 2px; }
.timeline-item p { margin-top: 6px; font-size: 14.5px; color: var(--c-ink-soft); }

/* ============ FAQ ============ */
.faq-list { max-width: 800px; margin: 0 auto; display: grid; gap: 12px; }
.faq-item {
  background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius);
  overflow: hidden;
}
.faq-q {
  width: 100%; display: flex; justify-content: space-between; align-items: center; gap: 16px;
  background: none; border: none; cursor: pointer;
  padding: 17px 22px; text-align: left;
  font-size: 16px; font-weight: 700; color: var(--c-ink); font-family: inherit;
}
.faq-q .faq-icon {
  flex-shrink: 0; width: 22px; height: 22px; border-radius: 50%;
  background: var(--c-primary-soft); color: var(--c-primary);
  display: flex; align-items: center; justify-content: center;
  font-size: 15px; font-weight: 800; line-height: 1;
  transition: transform 0.2s ease;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-a { display: none; padding: 0 22px 18px; font-size: 15px; color: var(--c-ink-soft); }
.faq-a p + p { margin-top: 8px; }
.faq-a a { font-weight: 600; }
.faq-a kbd {
  font-family: var(--font-mono); font-size: 12.5px;
  background: var(--c-bg-soft); border: 1px solid var(--c-line-strong);
  border-bottom-width: 2px; border-radius: 5px; padding: 1px 6px;
}

/* ============ CTA 横幅 ============ */
.cta-band {
  background:
    radial-gradient(900px 400px at 12% 0%, rgba(42,161,152,0.25), transparent 55%),
    linear-gradient(135deg, var(--c-primary-darker) 0%, var(--c-primary) 100%);
  color: #fff; border-radius: var(--radius-lg);
  padding: 52px 48px;
  display: flex; align-items: center; justify-content: space-between; gap: 32px;
  box-shadow: var(--shadow-md);
}
.cta-band h2 { font-size: 27px; font-weight: 800; }
.cta-band p { margin-top: 8px; color: rgba(255,255,255,0.82); font-size: 15.5px; max-width: 560px; }
.cta-band .btn-primary { background: #fff; color: var(--c-primary); }
.cta-band .btn-primary:hover { background: #EDF3FA; color: var(--c-primary-dark); }

/* ============ 页脚 ============ */
.site-footer { background: var(--c-primary-darker); color: rgba(255,255,255,0.78); margin-top: 80px; }
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 36px;
  padding: 52px 0 40px;
}
.footer-brand { display: flex; align-items: center; gap: 10px; color: #fff; margin-bottom: 14px; }
.footer-brand img { width: 130px;}
.footer-brand span { font-size: 18px; font-weight: 800; }
.footer-desc { font-size: 13.5px; line-height: 1.8; max-width: 340px; }
.site-footer h4 { color: #fff; font-size: 14px; font-weight: 700; margin-bottom: 14px; letter-spacing: 0.05em; }
.footer-col ul { list-style: none; padding: 0; display: grid; gap: 9px; }
.footer-col a { color: rgba(255,255,255,0.72); font-size: 14px; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.12);
  padding: 20px 0; font-size: 12.5px; color: rgba(255,255,255,0.55);
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px;
}
.footer-bottom p + p { text-align: right; }

/* ============ 下载弹窗 ============ */
.modal-overlay {
  position: fixed; inset: 0; z-index: 300;
  background: rgba(15, 32, 56, 0.55);
  display: none;
  align-items: center; justify-content: center;
  padding: 24px;
}
.modal-overlay.open { display: flex; }
.modal {
  background: #fff; border-radius: var(--radius-lg);
  width: 100%; max-width: 660px;
  box-shadow: var(--shadow-lg);
  max-height: calc(100dvh - 48px);
  overflow-y: auto;
  animation: modal-in 0.22s ease;
}
@keyframes modal-in {
  from { opacity: 0; transform: translateY(14px) scale(0.98); }
  to { opacity: 1; transform: none; }
}
.modal-head {
  display: flex; align-items: flex-start; justify-content: space-between; gap: 16px;
  padding: 24px 28px 0;
}
.modal-title { font-size: 21px; font-weight: 800; color: var(--c-ink); }
.modal-sub { font-size: 14px; color: var(--c-ink-mute); margin-top: 4px; }
.modal-close {
  flex-shrink: 0; width: 34px; height: 34px; border-radius: 8px;
  border: 1px solid var(--c-line); background: #fff; cursor: pointer;
  font-size: 16px; color: var(--c-ink-soft); line-height: 1;
}
.modal-close:hover { background: var(--c-bg-soft); }
.modal-body { padding: 22px 28px 28px; }
.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.qr-card {
  border: 1px solid var(--c-line); border-radius: var(--radius);
  padding: 20px 16px; text-align: center; background: var(--c-bg);
}
.qr-card:hover { border-color: var(--c-primary-light); }
.qr-img {
  width: 170px; height: 170px; margin: 0 auto 12px;
  background: #fff; border: 1px solid var(--c-line); border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  padding: 10px;
}
.qr-img img { width: 100%; height: 100%; object-fit: contain; }
.qr-img svg { width: 100%; height: 100%; }
.qr-name { font-size: 15px; font-weight: 700; color: var(--c-ink); }
.qr-hint { font-size: 12.5px; color: var(--c-ink-mute); margin-top: 3px; }
.modal-tips {
  margin-top: 18px; font-size: 13px; color: var(--c-ink-mute);
  background: var(--c-bg-soft); border-radius: 8px; padding: 12px 16px;
  line-height: 1.7;
}

/* ============ 返回顶部 ============ */
.back-top {
  position: fixed; right: 26px; bottom: 30px; z-index: 90;
  width: 44px; height: 44px; border-radius: 10px;
  background: var(--c-primary); color: #fff; border: none; cursor: pointer;
  box-shadow: var(--shadow-md);
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
}
.back-top.show { opacity: 1; visibility: visible; transform: none; }
.back-top:hover { background: var(--c-primary-dark); }

/* ============ 响应式 ============ */
@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .hero { padding: 56px 0 64px; }
  .hero-title { font-size: 34px; }
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .stats-band .wrap { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .cta-band { flex-direction: column; text-align: center; padding: 40px 28px; }
  .cta-band p { margin-left: auto; margin-right: auto; }
  .main-nav {
    display: none; position: absolute; top: 66px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--c-line);
    flex-direction: column; padding: 10px 20px 16px; gap: 4px;
    box-shadow: var(--shadow-md);
  }
  .main-nav.open { display: flex; }
  .nav-toggle { display: inline-flex; }
}

@media (max-width: 640px) {
  .section { padding: 52px 0; }
  .section-title { font-size: 26px; }
  .hero-title { font-size: 29px; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .qr-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .footer-bottom { flex-direction: column; }
  .footer-bottom p + p { text-align: left; }
  .btn-lg { padding: 13px 26px; font-size: 16px; }
  .header-actions .btn { display: none; }
}

/* ============ 打印 ============ */
@media print {
  .site-header, .site-footer, .back-top, .modal-overlay, .cta-band, .hero-cta { display: none; }
  body { background: #fff; }
}