/* ==========================================================================
   关税通 GoTariff · 官网统一样式
   主色: #3b82f6 (蓝) · 强调: #f59e0b (琥珀) · 深浅双主题 · 响应式
   ========================================================================== */

/* -------- 主题变量 -------- */
:root {
  --primary: #3b82f6;
  --primary-dark: #2563eb;
  --accent: #f59e0b;
  --accent-light: #fbbf24;
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 20px;
  --maxw: 1160px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow: 0 4px 16px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.12);
  --transition: 0.25s ease;
}

/* 深色（默认） */
:root,
html.dark {
  --bg: #0f172a;
  --bg-grad-1: rgba(59, 130, 246, 0.15);
  --bg-grad-2: rgba(99, 102, 241, 0.15);
  --bg-grad-3: #020617;
  --surface: rgba(30, 41, 59, 0.6);
  --surface-solid: #1e293b;
  --surface-2: rgba(51, 65, 85, 0.5);
  --border: rgba(148, 163, 184, 0.18);
  --border-strong: rgba(148, 163, 184, 0.3);
  --text: #f8fafc;
  --text-secondary: #94a3b8;
  --text-tertiary: #64748b;
  --nav-bg: rgba(15, 23, 42, 0.8);
}

/* 浅色 */
html.light {
  --bg: #f8fafc;
  --bg-grad-1: rgba(59, 130, 246, 0.08);
  --bg-grad-2: rgba(99, 102, 241, 0.06);
  --bg-grad-3: #f1f5f9;
  --surface: rgba(255, 255, 255, 0.85);
  --surface-solid: #ffffff;
  --surface-2: rgba(241, 245, 249, 0.8);
  --border: rgba(203, 213, 225, 0.6);
  --border-strong: rgba(148, 163, 184, 0.5);
  --text: #1e293b;
  --text-secondary: #475569;
  --text-tertiary: #64748b;
  --nav-bg: rgba(255, 255, 255, 0.8);
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow: 0 4px 16px rgba(15, 23, 42, 0.06);
  --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.1);
}

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

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  font-family: 'Inter', 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', sans-serif;
  background:
    radial-gradient(circle at top right, var(--bg-grad-1), transparent 40%),
    radial-gradient(circle at bottom left, var(--bg-grad-2), transparent 45%),
    linear-gradient(180deg, var(--bg-grad-3), var(--bg));
  background-attachment: fixed;
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  transition: color var(--transition);
}

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

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

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* -------- 顶部导航（nav.js 注入） -------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--nav-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  height: 64px; display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.nav-brand { display: flex; align-items: center; gap: 10px; }
.nav-brand img { width: 34px; height: 34px; }
.nav-brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.nav-brand-text .cn { font-size: 17px; font-weight: 700; color: var(--text); }
.nav-brand-text .en { font-size: 11px; color: var(--text-tertiary); letter-spacing: 0.04em; font-weight: 500; }

.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
.nav-links a {
  color: var(--text-secondary); font-size: 15px; font-weight: 500;
  padding: 8px 14px; border-radius: var(--radius-sm);
}
.nav-links a:hover { color: var(--text); background: var(--surface-2); }
.nav-links a.active { color: var(--primary); }

.nav-actions { display: flex; align-items: center; gap: 8px; }

/* 主题切换按钮 */
.theme-toggle {
  width: 38px; height: 38px; border-radius: 50%; border: 1px solid var(--border);
  background: var(--surface); color: var(--text-secondary); cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: all var(--transition);
}
.theme-toggle:hover { color: var(--text); border-color: var(--border-strong); }
.theme-toggle .icon-moon { display: none; }
html.light .theme-toggle .icon-moon { display: block; }
html.light .theme-toggle .icon-sun { display: none; }

/* 语言切换按钮 */
.lang-switch {
  height: 38px; padding: 0 12px; border-radius: 999px; border: 1px solid var(--border);
  background: var(--surface); color: var(--text-secondary); cursor: pointer;
  font-family: inherit; font-size: 13px; font-weight: 600; letter-spacing: 0.02em;
  display: flex; align-items: center; justify-content: center; transition: all var(--transition);
}
.lang-switch:hover { color: var(--text); border-color: var(--primary); }

/* 移动端汉堡 */
.nav-toggle { display: none; }

/* -------- 按钮 -------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: inherit; font-size: 15px; font-weight: 600; cursor: pointer;
  padding: 11px 22px; border-radius: var(--radius-sm); border: 1px solid transparent;
  transition: all var(--transition); white-space: nowrap; text-align: center;
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff; box-shadow: 0 4px 14px rgba(59, 130, 246, 0.35);
}
.btn-primary:hover { color: #fff; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(59, 130, 246, 0.45); }
.btn-ghost {
  background: var(--surface); color: var(--text); border-color: var(--border-strong);
}
.btn-ghost:hover { color: var(--text); border-color: var(--primary); }
.btn-sm { padding: 8px 16px; font-size: 14px; }
.btn-lg { padding: 14px 30px; font-size: 16px; }

/* -------- Hero 区 -------- */
.hero { padding: 80px 0 70px; position: relative; overflow: hidden; }
.hero-grid {
  display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center;
}
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--surface); border: 1px solid var(--border);
  padding: 6px 14px; border-radius: 999px; font-size: 13px; color: var(--text-secondary);
  margin-bottom: 22px;
}
.hero-eyebrow .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }
.hero h1 {
  font-size: clamp(30px, 4.4vw, 50px); font-weight: 800; line-height: 1.18;
  letter-spacing: -0.02em; margin-bottom: 20px;
}
.hero h1 .hl { color: var(--primary); }
.hero h1 .accent { color: var(--accent); }
.hero-sub { font-size: 18px; color: var(--text-secondary); margin-bottom: 32px; max-width: 540px; }
.hero-ctas { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 28px; }
.hero-trust { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; font-size: 13px; color: var(--text-tertiary); }
.hero-trust .check { display: inline-flex; align-items: center; gap: 6px; }
.hero-trust .check::before { content: ''; width: 5px; height: 5px; border-radius: 50%; background: var(--primary); display: inline-block; }

/* Hero mockup：自绘策略对比卡片 */
.hero-mockup {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
  overflow: hidden; backdrop-filter: blur(10px);
}
.mockup-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 18px; border-bottom: 1px solid var(--border);
  background: var(--surface-2);
}
.mockup-head .title { font-size: 13px; font-weight: 600; color: var(--text-secondary); }
.mockup-dots { display: flex; gap: 6px; }
.mockup-dots span { width: 10px; height: 10px; border-radius: 50%; background: var(--border-strong); }
.mockup-kpis { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--border); }
.mockup-kpi { background: var(--surface); padding: 16px 14px; text-align: center; }
.mockup-kpi .label { font-size: 11px; color: var(--text-tertiary); margin-bottom: 4px; }
.mockup-kpi .value { font-size: 18px; font-weight: 700; color: var(--text); }
.mockup-kpi .value.save { color: var(--accent); }
.mockup-list { padding: 8px; }
.mockup-row {
  display: grid; grid-template-columns: 24px 1fr auto auto; align-items: center; gap: 10px;
  padding: 10px 12px; border-radius: var(--radius-sm); font-size: 13px;
}
.mockup-row.best { background: rgba(34, 197, 94, 0.1); border: 1px solid rgba(34, 197, 94, 0.25); }
.mockup-row .rank { width: 20px; height: 20px; border-radius: 50%; background: var(--surface-2); color: var(--text-tertiary); font-size: 11px; display: flex; align-items: center; justify-content: center; font-weight: 600; }
.mockup-row.best .rank { background: var(--accent); color: #fff; }
.mockup-row .origin { font-weight: 600; color: var(--text); }
.mockup-row .cost { font-weight: 700; color: var(--text); font-variant-numeric: tabular-nums; }
.mockup-row .tag { font-size: 10px; padding: 2px 7px; border-radius: 999px; background: rgba(34, 197, 94, 0.15); color: #22c55e; font-weight: 600; }

/* -------- 通用 section -------- */
section { padding: 72px 0; }
.section-head { text-align: center; max-width: 680px; margin: 0 auto 48px; }
.section-eyebrow {
  display: inline-block; font-size: 13px; font-weight: 600; color: var(--primary);
  text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 12px;
}
.section-head h2 { font-size: clamp(26px, 3.2vw, 38px); font-weight: 800; letter-spacing: -0.02em; margin-bottom: 14px; }
.section-head p { font-size: 17px; color: var(--text-secondary); }

/* KPI 数字带 */
.kpi-band {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--border); border: 1px solid var(--border);
  border-radius: var(--radius); overflow: hidden;
}
.kpi-item { background: var(--surface); padding: 28px 20px; text-align: center; }
.kpi-item .num { font-size: 36px; font-weight: 800; color: var(--primary); line-height: 1; margin-bottom: 8px; font-variant-numeric: tabular-nums; }
.kpi-item .num .unit { font-size: 18px; color: var(--accent); margin-left: 2px; }
.kpi-item .desc { font-size: 14px; color: var(--text-secondary); }

/* 痛点对照 */
.compare-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }

/* 务实叙述段（替代工整对照） */
.lede {
  max-width: 760px; margin: 0 auto; padding: 36px 0;
  font-size: 19px; line-height: 1.85; color: var(--text-secondary); text-align: left;
}
.lede p { margin-bottom: 18px; }
.lede strong { color: var(--text); font-weight: 600; }
.lede .pull {
  display: block; margin: 24px 0 8px; padding: 16px 20px;
  border-left: 3px solid var(--accent); background: var(--surface-2);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0; font-size: 17px;
}

/* 核心能力四宫格（正式、简洁） */
.cap-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--border); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.cap-item { background: var(--surface); padding: 30px 24px; }
.cap-item .num { font-size: 34px; font-weight: 800; color: var(--primary); line-height: 1; margin-bottom: 10px; font-variant-numeric: tabular-nums; }
.cap-item .num .unit { font-size: 16px; color: var(--text-tertiary); margin-left: 3px; font-weight: 600; }
.cap-item .desc { font-size: 14px; color: var(--text-secondary); line-height: 1.5; }
.compare-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 32px; backdrop-filter: blur(8px);
}
.compare-card.before { border-color: rgba(239, 68, 68, 0.25); }
.compare-card.after { border-color: rgba(34, 197, 94, 0.3); box-shadow: 0 0 0 1px rgba(34, 197, 94, 0.1); }
.compare-card h3 { display: flex; align-items: center; gap: 10px; font-size: 19px; margin-bottom: 18px; }
.compare-card.before h3 { color: #ef4444; }
.compare-card.after h3 { color: #22c55e; }
.compare-card ul { list-style: none; }
.compare-card li { display: flex; gap: 10px; padding: 8px 0; font-size: 15px; color: var(--text-secondary); border-bottom: 1px dashed var(--border); }
.compare-card li:last-child { border-bottom: none; }
.compare-card li svg { flex-shrink: 0; margin-top: 4px; }
.compare-card.before li svg { color: #ef4444; }
.compare-card.after li svg { color: #22c55e; }

/* 功能卡片网格 */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.feature-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; backdrop-filter: blur(8px); transition: all var(--transition);
}
.feature-card:hover { transform: translateY(-4px); border-color: var(--primary); box-shadow: var(--shadow-lg); }
.feature-icon {
  width: 48px; height: 48px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.15), rgba(59, 130, 246, 0.05));
  color: var(--primary); margin-bottom: 18px;
}
.feature-card h3 { font-size: 18px; margin-bottom: 10px; }
.feature-card p { font-size: 14.5px; color: var(--text-secondary); }

/* 数据源徽章 */
.source-band { text-align: center; }
.source-badges { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 24px; }
.source-badge {
  display: inline-flex; align-items: center; gap: 8px; padding: 10px 18px;
  background: var(--surface); border: 1px solid var(--border); border-radius: 999px;
  font-size: 14px; font-weight: 600; color: var(--text-secondary);
}
.source-badge .dot { width: 8px; height: 8px; border-radius: 50%; background: #22c55e; }

/* 案例演示 */
.demo-case { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 36px; backdrop-filter: blur(8px); }
.demo-steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-bottom: 32px; }
.demo-step { text-align: center; }
.demo-step .num { width: 36px; height: 36px; border-radius: 50%; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: #fff; font-weight: 700; display: inline-flex; align-items: center; justify-content: center; margin-bottom: 12px; }
.demo-step h4 { font-size: 16px; margin-bottom: 6px; }
.demo-step p { font-size: 13.5px; color: var(--text-secondary); }
.demo-result { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius); }
.demo-result table { width: 100%; border-collapse: collapse; min-width: 520px; }
.demo-result th { background: var(--surface-2); color: var(--text-secondary); font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; padding: 12px 16px; text-align: left; }
.demo-result td { padding: 13px 16px; border-top: 1px solid var(--border); font-size: 14px; }
.demo-result tr.best { background: rgba(34, 197, 94, 0.08); }
.demo-result tr.best td:first-child { font-weight: 700; }
.demo-result .save { color: var(--accent); font-weight: 700; }
.demo-note { margin-top: 16px; font-size: 13px; color: var(--text-tertiary); text-align: center; }

/* 套餐表 */
.pricing-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; align-items: start; }
.price-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px 22px; backdrop-filter: blur(8px); transition: all var(--transition); position: relative;
}
.price-card.popular { border-color: var(--primary); box-shadow: 0 0 0 1px var(--primary), var(--shadow); }
.price-card .badge { position: absolute; top: -11px; left: 50%; transform: translateX(-50%); background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: #fff; font-size: 11px; font-weight: 700; padding: 4px 14px; border-radius: 999px; letter-spacing: 0.04em; }
.price-card h3 { font-size: 18px; margin-bottom: 8px; }
.price-card .price { font-size: 34px; font-weight: 800; margin-bottom: 4px; }
.price-card .price .per { font-size: 14px; font-weight: 500; color: var(--text-tertiary); }
.price-card .price .custom { font-size: 22px; color: var(--text-secondary); }
.price-card .desc { font-size: 13px; color: var(--text-tertiary); margin-bottom: 18px; min-height: 36px; }
.price-card ul { list-style: none; margin-bottom: 22px; }
.price-card li { display: flex; gap: 8px; padding: 7px 0; font-size: 13.5px; color: var(--text-secondary); border-top: 1px dashed var(--border); }
.price-card li:first-child { border-top: none; }
.price-card li svg { flex-shrink: 0; margin-top: 3px; color: var(--primary); }
.price-card .btn { width: 100%; }

/* 适用人群 */
.audience-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; }
.audience-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px 18px; text-align: center; transition: all var(--transition); }
.audience-card:hover { border-color: var(--primary); transform: translateY(-3px); }
.audience-card .emoji { font-size: 32px; margin-bottom: 12px; }
.audience-card h4 { font-size: 15px; margin-bottom: 6px; }
.audience-card p { font-size: 12.5px; color: var(--text-secondary); }

/* FAQ 手风琴 */
.faq-list { max-width: 760px; margin: 0 auto; }
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 12px; background: var(--surface); overflow: hidden; }
.faq-q { width: 100%; text-align: left; background: none; border: none; cursor: pointer; padding: 18px 22px; font-family: inherit; font-size: 16px; font-weight: 600; color: var(--text); display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq-q .chev { flex-shrink: 0; transition: transform var(--transition); color: var(--text-tertiary); }
.faq-item.open .faq-q .chev { transform: rotate(180deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s ease; }
.faq-a-inner { padding: 0 22px 18px; color: var(--text-secondary); font-size: 14.5px; line-height: 1.7; }

/* 底部 CTA */
.cta-band {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: var(--radius-lg); padding: 56px 40px; text-align: center; color: #fff;
  position: relative; overflow: hidden;
}
.cta-band::before { content: ''; position: absolute; inset: 0; background: radial-gradient(circle at 30% 20%, rgba(255,255,255,0.15), transparent 50%); }
.cta-band h2 { font-size: clamp(24px, 3vw, 34px); font-weight: 800; margin-bottom: 14px; position: relative; }
.cta-band p { font-size: 17px; opacity: 0.9; margin-bottom: 28px; position: relative; }
.cta-band .btn { background: #fff; color: var(--primary-dark); position: relative; }
.cta-band .btn:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.2); }

/* -------- 页脚（nav.js 注入） -------- */
.site-footer { border-top: 1px solid var(--border); padding: 48px 0 28px; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 32px; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.footer-brand img { width: 32px; height: 32px; }
.footer-brand .cn { font-size: 16px; font-weight: 700; }
.footer-brand .en { font-size: 11px; color: var(--text-tertiary); }
.footer-about { font-size: 13.5px; color: var(--text-secondary); max-width: 300px; }
.footer-col h4 { font-size: 14px; font-weight: 600; margin-bottom: 14px; color: var(--text); }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 9px; }
.footer-col a { color: var(--text-secondary); font-size: 14px; }
.footer-col a:hover { color: var(--primary); }
.footer-bottom { border-top: 1px solid var(--border); padding-top: 22px; display: flex; justify-content: space-between; align-items: center; gap: 16px; flex-wrap: wrap; font-size: 13px; color: var(--text-tertiary); }
.disclaimer { font-size: 12.5px; color: var(--text-tertiary); line-height: 1.6; padding: 14px 18px; background: var(--surface-2); border-radius: var(--radius-sm); margin-bottom: 22px; border-left: 3px solid var(--accent); }

/* -------- 使用说明页专用 -------- */
.guide-layout { display: grid; grid-template-columns: 240px 1fr; gap: 40px; padding: 48px 0; align-items: start; }
.guide-toc { position: sticky; top: 88px; }
.guide-toc h4 { font-size: 13px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-tertiary); margin-bottom: 14px; }
.guide-toc ul { list-style: none; }
.guide-toc li { margin-bottom: 4px; }
.guide-toc a { display: block; padding: 7px 12px; border-radius: var(--radius-sm); font-size: 14px; color: var(--text-secondary); border-left: 2px solid transparent; }
.guide-toc a:hover { color: var(--text); background: var(--surface-2); }
.guide-toc a.active { color: var(--primary); border-left-color: var(--primary); background: var(--surface-2); }

.doc-block { margin-bottom: 56px; scroll-margin-top: 88px; }
.doc-block h2 { font-size: 26px; font-weight: 800; margin-bottom: 8px; padding-bottom: 12px; border-bottom: 2px solid var(--border); }
.doc-block h3 { font-size: 18px; font-weight: 700; margin: 26px 0 12px; color: var(--text); }
.doc-block h4 { font-size: 15px; font-weight: 600; margin: 18px 0 8px; color: var(--primary); }
.doc-block p { color: var(--text-secondary); margin-bottom: 12px; }
.doc-block ul, .doc-block ol { color: var(--text-secondary); margin: 0 0 14px 4px; }
.doc-block li { margin-bottom: 6px; padding-left: 6px; }

.doc-table { width: 100%; border-collapse: collapse; margin: 14px 0; border: 1px solid var(--border); border-radius: var(--radius-sm); overflow: hidden; }
.doc-table th { background: var(--surface-2); color: var(--text-secondary); font-size: 13px; font-weight: 600; padding: 10px 14px; text-align: left; }
.doc-table td { padding: 10px 14px; border-top: 1px solid var(--border); font-size: 14px; color: var(--text-secondary); }
.doc-table td:first-child { color: var(--text); font-weight: 500; }

.steps-list { counter-reset: step; list-style: none; margin: 16px 0; }
.steps-list li { counter-increment: step; position: relative; padding: 10px 0 10px 44px; color: var(--text-secondary); }
.steps-list li::before { content: counter(step); position: absolute; left: 0; top: 8px; width: 28px; height: 28px; border-radius: 50%; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: #fff; font-size: 13px; font-weight: 700; display: flex; align-items: center; justify-content: center; }

.screenshot-ph {
  border: 2px dashed var(--border-strong); border-radius: var(--radius); padding: 40px;
  text-align: center; color: var(--text-tertiary); font-size: 14px; margin: 18px 0;
  background: var(--surface-2);
}
.callout { padding: 14px 18px; border-radius: var(--radius-sm); margin: 14px 0; font-size: 14px; }
.callout.info { background: rgba(59, 130, 246, 0.1); border-left: 3px solid var(--primary); color: var(--text); }
.callout.warn { background: rgba(245, 158, 11, 0.1); border-left: 3px solid var(--accent); color: var(--text); }

/* -------- 下载页专用 -------- */
.status-banner { background: rgba(245, 158, 11, 0.12); border: 1px solid rgba(245, 158, 11, 0.3); border-radius: var(--radius); padding: 14px 20px; display: flex; align-items: center; gap: 12px; margin-bottom: 32px; font-size: 14.5px; }
.status-banner svg { flex-shrink: 0; color: var(--accent); }
.dl-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-bottom: 40px; }
.dl-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 32px; backdrop-filter: blur(8px); }
.dl-card.recommended { border-color: var(--primary); box-shadow: 0 0 0 1px var(--primary); }
.dl-card .tag { display: inline-block; background: var(--primary); color: #fff; font-size: 11px; font-weight: 700; padding: 3px 10px; border-radius: 999px; margin-bottom: 12px; }
.dl-card h3 { font-size: 20px; margin-bottom: 10px; }
.dl-card p { color: var(--text-secondary); font-size: 14.5px; margin-bottom: 18px; }
.qr-ph { width: 180px; height: 180px; border: 2px dashed var(--border-strong); border-radius: var(--radius); display: flex; align-items: center; justify-content: center; color: var(--text-tertiary); font-size: 13px; margin: 0 auto 18px; background: var(--surface-2); }
.version-info { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; margin-bottom: 24px; }
.version-info h3 { font-size: 17px; margin-bottom: 12px; }
.sys-req { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
.sys-req .chip { background: var(--surface-2); border: 1px solid var(--border); padding: 6px 14px; border-radius: 999px; font-size: 13px; color: var(--text-secondary); }

/* -------- 动画 -------- */
@keyframes fadeUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
.reveal { opacity: 0; }
.reveal.in { animation: fadeUp 0.6s ease-out forwards; }

/* -------- 响应式 -------- */
@media (max-width: 960px) {
  .feature-grid, .pricing-grid { grid-template-columns: repeat(2, 1fr); }
  .audience-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
}
@media (max-width: 768px) {
  .nav-links, .nav-actions .btn { display: none; }
  .nav-toggle {
    display: flex; flex-direction: column; gap: 5px; width: 38px; height: 38px;
    background: none; border: 1px solid var(--border); border-radius: var(--radius-sm); cursor: pointer;
    align-items: center; justify-content: center;
  }
  .nav-toggle span { width: 18px; height: 2px; background: var(--text); border-radius: 1px; transition: var(--transition); }
  .nav-links.open {
    display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0;
    background: var(--surface-solid); border-bottom: 1px solid var(--border); padding: 12px 24px; gap: 2px;
  }
  .nav-links.open a { padding: 12px 14px; }

  .hero { padding: 48px 0 40px; }
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  section { padding: 52px 0; }
  .kpi-band { grid-template-columns: repeat(2, 1fr); }
  .compare-grid, .dl-grid { grid-template-columns: 1fr; }
  .demo-steps { grid-template-columns: 1fr; }
  .pricing-grid, .feature-grid { grid-template-columns: 1fr; }
  .audience-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }

  .guide-layout { grid-template-columns: 1fr; }
  .guide-toc { position: static; margin-bottom: 24px; }
  .guide-toc ul { display: none; }
  .guide-toc.open ul { display: block; }
  .cta-band { padding: 40px 24px; }
}
@media (max-width: 480px) {
  .audience-grid { grid-template-columns: 1fr; }
  .container { padding: 0 18px; }
  .hero h1 { font-size: 28px; }
}