/* ============================================================
   Nooko.Agent 诺可智能体 - 官网主样式
   全静态、移动优先、暗色模式、零依赖
   ============================================================ */

/* ---------- 设计变量 ---------- */
:root {
  --color-primary: #6366f1;
  --color-primary-600: #4f46e5;
  --color-primary-700: #4338ca;
  --color-accent: #8b5cf6;
  --color-cyan: #06b6d4;
  --color-emerald: #10b981;
  --color-amber: #f59e0b;
  --color-rose: #f43f5e;

  --grad-brand: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #06b6d4 100%);
  --grad-brand-soft: linear-gradient(135deg, rgba(99, 102, 241, 0.12) 0%, rgba(139, 92, 246, 0.12) 50%, rgba(6, 182, 212, 0.12) 100%);
  --grad-hero: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(99, 102, 241, 0.25) 0%, transparent 60%),
               radial-gradient(ellipse 60% 50% at 90% 20%, rgba(139, 92, 246, 0.18) 0%, transparent 60%),
               radial-gradient(ellipse 60% 50% at 10% 30%, rgba(6, 182, 212, 0.15) 0%, transparent 60%);

  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --bg-muted: #f1f5f9;
  --bg-card: #ffffff;
  --bg-code: #0f172a;
  --bg-overlay: rgba(255, 255, 255, 0.7);

  --fg: #0f172a;
  --fg-soft: #334155;
  --fg-muted: #64748b;
  --fg-faint: #94a3b8;

  --border: #e2e8f0;
  --border-strong: #cbd5e1;

  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04), 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.05);
  --shadow-lg: 0 20px 25px -5px rgba(15, 23, 42, 0.12), 0 8px 10px -6px rgba(15, 23, 42, 0.08);
  --shadow-glow: 0 0 0 1px rgba(99, 102, 241, 0.2), 0 8px 24px -4px rgba(99, 102, 241, 0.35);

  --radius-sm: 6px;
  --radius: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 999px;

  --container: 1200px;
  --container-narrow: 880px;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", "Cascadia Code", "Fira Code", Consolas, Monaco, monospace;

  --header-h: 68px;
}

[data-theme="dark"] {
  --bg: #0a0e1a;
  --bg-soft: #0f172a;
  --bg-muted: #1e293b;
  --bg-card: #111827;
  --bg-overlay: rgba(10, 14, 26, 0.7);

  --fg: #f1f5f9;
  --fg-soft: #cbd5e1;
  --fg-muted: #94a3b8;
  --fg-faint: #64748b;

  --border: #1e293b;
  --border-strong: #334155;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.6);

  --grad-hero: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(99, 102, 241, 0.18) 0%, transparent 60%),
               radial-gradient(ellipse 60% 50% at 90% 20%, rgba(139, 92, 246, 0.14) 0%, transparent 60%),
               radial-gradient(ellipse 60% 50% at 10% 30%, rgba(6, 182, 212, 0.12) 0%, transparent 60%);
}

/* ---------- 基础重置 ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 24px);
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}
img, svg, video { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
ul, ol { list-style: none; }
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 通用容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}
.container-narrow {
  width: 100%;
  max-width: var(--container-narrow);
  margin-inline: auto;
  padding-inline: 24px;
}
.section {
  padding-block: clamp(56px, 8vw, 110px);
}
.section-sm { padding-block: clamp(40px, 5vw, 64px); }
.section-muted { background: var(--bg-soft); }
.section-dark { background: var(--bg-code); color: #f1f5f9; }
.bg-grad { background: var(--grad-brand-soft); }

.text-center { text-align: center; }
.text-grad {
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* ---------- 标题排版 ---------- */
.h-display {
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.025em;
}
.h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.15;
  font-weight: 800;
  letter-spacing: -0.02em;
}
.h2 {
  font-size: clamp(1.6rem, 3vw, 2.25rem);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.015em;
}
.h3 {
  font-size: clamp(1.25rem, 2vw, 1.5rem);
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.lead {
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  line-height: 1.65;
  color: var(--fg-soft);
}
.muted { color: var(--fg-muted); }
.faint { color: var(--fg-faint); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: var(--grad-brand-soft);
  border: 1px solid rgba(99, 102, 241, 0.18);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.section-head {
  max-width: 720px;
  margin-inline: auto;
  text-align: center;
  margin-bottom: clamp(40px, 5vw, 64px);
}
.section-head .eyebrow { margin-bottom: 18px; }
.section-head .lead { margin-top: 16px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius);
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease, color 0.18s ease, border-color 0.18s ease;
  white-space: nowrap;
  user-select: none;
}
.btn svg { width: 18px; height: 18px; }
.btn-primary {
  background: var(--grad-brand);
  color: #fff;
  box-shadow: var(--shadow-glow);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 0 1px rgba(99, 102, 241, 0.3), 0 12px 32px -4px rgba(99, 102, 241, 0.5);
}
.btn-ghost {
  background: var(--bg-card);
  color: var(--fg);
  border: 1px solid var(--border-strong);
}
.btn-ghost:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-2px);
}
.btn-lg { padding: 14px 30px; font-size: 1rem; }
.btn-sm { padding: 8px 16px; font-size: 0.85rem; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-overlay);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--border);
  transition: background 0.3s ease, border-color 0.3s ease;
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}
.brand-logo {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--grad-brand);
  color: #fff;
  box-shadow: var(--shadow-glow);
}
.brand-logo svg { width: 20px; height: 20px; }
.brand small {
  display: block;
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--fg-muted);
  letter-spacing: 0.04em;
  margin-top: -2px;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  padding: 8px 14px;
  border-radius: var(--radius);
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--fg-soft);
  transition: color 0.15s ease, background 0.15s ease;
}
.nav-link:hover { color: var(--color-primary); background: var(--bg-muted); }
.nav-link.active { color: var(--color-primary); font-weight: 600; }
.nav-actions { display: flex; align-items: center; gap: 10px; }

.theme-toggle {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all 0.2s ease;
}
.theme-toggle:hover { border-color: var(--color-primary); color: var(--color-primary); transform: rotate(15deg); }
.theme-toggle svg { width: 18px; height: 18px; }
[data-theme="dark"] .theme-toggle .sun { display: block; }
[data-theme="dark"] .theme-toggle .moon { display: none; }
.theme-toggle .sun { display: none; }
.theme-toggle .moon { display: block; }

.nav-toggle {
  display: none;
  width: 38px;
  height: 38px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  align-items: center;
  justify-content: center;
}
.nav-toggle svg { width: 20px; height: 20px; }

@media (max-width: 920px) {
  .nav-toggle { display: inline-flex; }
  .nav-menu {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 16px 24px 24px;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-120%);
    transition: transform 0.3s ease;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
  }
  .nav-menu.open { transform: translateY(0); }
  .nav-link { padding: 12px 14px; font-size: 1rem; }
  .nav-actions .btn-ghost.mobile-hide { display: none; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding-block: clamp(72px, 12vw, 140px) clamp(56px, 8vw, 96px);
  background: var(--grad-hero);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(99, 102, 241, 0.04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(99, 102, 241, 0.04) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 60% 50% at 50% 30%, #000 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 60% 50% at 50% 30%, #000 0%, transparent 70%);
  pointer-events: none;
}
.hero-inner {
  position: relative;
  display: grid;
  gap: 28px;
  text-align: center;
  max-width: 880px;
  margin-inline: auto;
}
.hero h1 .text-grad { display: inline-block; }
.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  margin-top: 8px;
}
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 28px;
  justify-content: center;
  align-items: center;
  margin-top: 18px;
  color: var(--fg-muted);
  font-size: 0.9rem;
}
.hero-meta-item { display: inline-flex; align-items: center; gap: 8px; }
.hero-meta-item svg { width: 16px; height: 16px; color: var(--color-emerald); }

.hero-preview {
  position: relative;
  margin-top: clamp(40px, 6vw, 64px);
  border-radius: var(--radius-xl);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
.hero-preview-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-soft);
}
.hero-preview-bar span {
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--border-strong);
}
.hero-preview-bar span:nth-child(1) { background: #ff5f57; }
.hero-preview-bar span:nth-child(2) { background: #febc2e; }
.hero-preview-bar span:nth-child(3) { background: #28c840; }
.hero-preview-bar .url {
  margin-left: 12px;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  border: 1px solid var(--border);
  font-size: 0.78rem;
  color: var(--fg-muted);
  font-family: var(--font-mono);
}
.hero-preview-body { padding: 24px; display: grid; gap: 16px; }

/* ---------- 卡片网格 ---------- */
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 26px;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  position: relative;
  overflow: hidden;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(99, 102, 241, 0.3);
}
.card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  display: grid;
  place-items: center;
  background: var(--grad-brand-soft);
  color: var(--color-primary);
  margin-bottom: 18px;
}
.card-icon svg { width: 24px; height: 24px; }
.card h3 { margin-bottom: 8px; }
.card p { color: var(--fg-muted); font-size: 0.94rem; line-height: 1.6; }
.card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 14px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-primary);
}
.card-link svg { width: 14px; height: 14px; transition: transform 0.2s ease; }
.card:hover .card-link svg { transform: translateX(4px); }

/* ---------- 特性列表卡片 ---------- */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(40px, 6vw, 80px);
  align-items: center;
}
.feature-row + .feature-row { margin-top: clamp(56px, 8vw, 96px); }
.feature-row.reverse .feature-visual { order: -1; }
@media (max-width: 820px) {
  .feature-row { grid-template-columns: 1fr; }
  .feature-row.reverse .feature-visual { order: 0; }
}
.feature-content .eyebrow { margin-bottom: 16px; }
.feature-content h2 { margin-bottom: 16px; }
.feature-content p { color: var(--fg-soft); margin-bottom: 18px; }
.feature-list { display: grid; gap: 10px; margin-top: 18px; }
.feature-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.94rem;
  color: var(--fg-soft);
}
.feature-list svg {
  width: 18px; height: 18px;
  color: var(--color-emerald);
  flex-shrink: 0;
  margin-top: 3px;
}
.feature-visual {
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 24px;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}
.feature-visual::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--grad-brand-soft);
  opacity: 0.5;
  pointer-events: none;
}

/* ---------- 模拟界面 ---------- */
.mock {
  position: relative;
  background: var(--bg-soft);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  font-size: 0.85rem;
}
.mock-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-card);
  font-weight: 600;
  font-size: 0.82rem;
}
.mock-head .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--color-primary); }
.mock-body { padding: 16px; display: grid; gap: 12px; }
.mock-msg {
  display: flex;
  gap: 10px;
  align-items: flex-start;
}
.mock-avatar {
  width: 26px; height: 26px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
  flex-shrink: 0;
}
.mock-avatar.ai { background: var(--grad-brand); }
.mock-avatar.user { background: var(--color-emerald); }
.mock-bubble {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 8px 12px;
  border-radius: var(--radius);
  color: var(--fg-soft);
  font-size: 0.82rem;
  line-height: 1.5;
}
.mock-bubble.ai { background: var(--grad-brand-soft); border-color: rgba(99, 102, 241, 0.2); }
.mock-node {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 12px;
  font-size: 0.82rem;
  display: flex;
  align-items: center;
  gap: 8px;
}
.mock-node .ic {
  width: 22px; height: 22px;
  border-radius: 6px;
  display: grid; place-items: center;
  background: var(--grad-brand);
  color: #fff; font-size: 0.7rem;
}

/* ---------- 数字统计 ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
@media (max-width: 700px) { .stats { grid-template-columns: repeat(2, 1fr); } }
.stat {
  text-align: center;
  padding: 24px 16px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border);
}
.stat-num {
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
}
.stat-label { margin-top: 8px; color: var(--fg-muted); font-size: 0.92rem; }

/* ---------- 代码块 ---------- */
.code-block {
  background: var(--bg-code);
  border-radius: var(--radius-md);
  border: 1px solid #1e293b;
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.65;
}
.code-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: #1e293b;
  color: #cbd5e1;
  font-size: 0.78rem;
  border-bottom: 1px solid #334155;
}
.code-head .lang { color: var(--color-cyan); font-weight: 600; }
.code-body {
  padding: 18px 20px;
  overflow-x: auto;
  color: #e2e8f0;
}
.code-body pre { white-space: pre; }
.code-body .c-key { color: #c084fc; }
.code-body .c-str { color: #86efac; }
.code-body .c-num { color: #fcd34d; }
.code-body .c-com { color: #64748b; font-style: italic; }
.code-body .c-fn { color: #60a5fa; }

/* ---------- 步骤 ---------- */
.steps { display: grid; gap: 0; counter-reset: step; }
.step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 24px;
  padding-block: 24px;
  border-top: 1px solid var(--border);
}
.step:first-child { border-top: none; }
.step-num {
  counter-increment: step;
  width: 48px; height: 48px;
  border-radius: 50%;
  background: var(--grad-brand);
  color: #fff;
  display: grid; place-items: center;
  font-weight: 700;
  font-size: 1.1rem;
  box-shadow: var(--shadow-glow);
}
.step-num::before { content: counter(step); }
.step h3 { margin-bottom: 6px; }
.step p { color: var(--fg-muted); }

/* ---------- 价格卡片 ---------- */
.price-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: stretch;
}
@media (max-width: 900px) { .price-grid { grid-template-columns: 1fr; max-width: 480px; margin-inline: auto; } }
.price-card {
  display: flex;
  flex-direction: column;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  position: relative;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.price-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.price-card.featured {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-glow);
  background: linear-gradient(180deg, rgba(99, 102, 241, 0.04) 0%, var(--bg-card) 30%);
}
.price-badge {
  position: absolute;
  top: -12px; left: 50%;
  transform: translateX(-50%);
  background: var(--grad-brand);
  color: #fff;
  font-size: 0.74rem;
  font-weight: 700;
  padding: 5px 14px;
  border-radius: var(--radius-full);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  white-space: nowrap;
}
.price-name { font-size: 1.15rem; font-weight: 700; }
.price-desc { color: var(--fg-muted); font-size: 0.9rem; margin-top: 4px; min-height: 40px; }
.price-amount {
  margin-top: 20px;
  display: flex;
  align-items: baseline;
  gap: 6px;
}
.price-amount .num { font-size: 2.5rem; font-weight: 800; letter-spacing: -0.02em; }
.price-amount .unit { color: var(--fg-muted); font-size: 0.92rem; }
.price-features { margin: 22px 0 26px; display: grid; gap: 10px; flex: 1; }
.price-features li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.92rem;
  color: var(--fg-soft);
}
.price-features svg { width: 18px; height: 18px; color: var(--color-emerald); flex-shrink: 0; margin-top: 2px; }
.price-card .btn { width: 100%; }

/* ---------- FAQ ---------- */
.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 18px 0;
}
.faq-q {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-weight: 600;
  font-size: 1.02rem;
  cursor: pointer;
  text-align: left;
  width: 100%;
}
.faq-q::after {
  content: "+";
  font-size: 1.5rem;
  color: var(--color-primary);
  transition: transform 0.2s ease;
  flex-shrink: 0;
}
.faq-item.open .faq-q::after { transform: rotate(45deg); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, margin-top 0.3s ease;
  color: var(--fg-muted);
  line-height: 1.7;
}
.faq-item.open .faq-a { max-height: 400px; margin-top: 12px; }

/* ---------- 标签/胶囊 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  background: var(--bg-muted);
  color: var(--fg-soft);
  font-size: 0.8rem;
  font-weight: 500;
}
.tag-grad {
  background: var(--grad-brand-soft);
  color: var(--color-primary);
  border: 1px solid rgba(99, 102, 241, 0.2);
}
.tags { display: flex; flex-wrap: wrap; gap: 8px; }

/* ---------- 场景卡片 ---------- */
.scenario-card {
  position: relative;
  border-radius: var(--radius-md);
  padding: 28px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.scenario-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.scenario-card .emoji { font-size: 2rem; }
.scenario-card h3 { margin: 12px 0 8px; }
.scenario-card p { color: var(--fg-muted); font-size: 0.92rem; }

/* ---------- CTA 区块 ---------- */
.cta-band {
  position: relative;
  border-radius: var(--radius-xl);
  background: var(--grad-brand);
  color: #fff;
  padding: clamp(40px, 6vw, 64px);
  text-align: center;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.cta-band::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 20% 20%, rgba(255,255,255,0.18) 0%, transparent 30%),
    radial-gradient(circle at 80% 80%, rgba(255,255,255,0.12) 0%, transparent 30%);
}
.cta-band > * { position: relative; }
.cta-band h2 { color: #fff; margin-bottom: 14px; }
.cta-band p { color: rgba(255,255,255,0.9); margin-bottom: 28px; font-size: 1.1rem; }
.cta-band .btn-primary {
  background: #fff;
  color: var(--color-primary-700);
  box-shadow: 0 10px 30px -10px rgba(0,0,0,0.4);
}
.cta-band .btn-primary:hover { background: #f8fafc; transform: translateY(-2px); }
.cta-band .btn-ghost {
  background: rgba(255,255,255,0.12);
  color: #fff;
  border-color: rgba(255,255,255,0.3);
  backdrop-filter: blur(10px);
}
.cta-band .btn-ghost:hover { background: rgba(255,255,255,0.2); border-color: rgba(255,255,255,0.5); }
.cta-band .hero-cta { margin-top: 0; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--border);
  padding-block: 64px 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(4, 1fr);
  gap: 40px;
}
@media (max-width: 880px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
}
.footer-brand .brand { margin-bottom: 14px; }
.footer-brand p { color: var(--fg-muted); font-size: 0.92rem; max-width: 280px; }
.footer-social { display: flex; gap: 10px; margin-top: 18px; }
.footer-social a {
  width: 36px; height: 36px;
  display: grid; place-items: center;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all 0.18s ease;
}
.footer-social a:hover { color: var(--color-primary); border-color: var(--color-primary); transform: translateY(-2px); }
.footer-social svg { width: 18px; height: 18px; }
.footer-col h4 {
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-muted);
  margin-bottom: 16px;
}
.footer-col ul { display: grid; gap: 10px; }
.footer-col a {
  color: var(--fg-soft);
  font-size: 0.92rem;
  transition: color 0.15s ease;
}
.footer-col a:hover { color: var(--color-primary); }
.footer-bottom {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  color: var(--fg-muted);
  font-size: 0.86rem;
}
.footer-bottom a { color: var(--fg-muted); }
.footer-bottom a:hover { color: var(--color-primary); }

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--fg-muted);
  margin-bottom: 20px;
}
.breadcrumb a:hover { color: var(--color-primary); }
.breadcrumb svg { width: 14px; height: 14px; }
.breadcrumb .sep { color: var(--fg-faint); }

/* ---------- 页面通用 hero (子页) ---------- */
.page-hero {
  position: relative;
  padding-block: clamp(56px, 8vw, 96px);
  background: var(--grad-hero);
  text-align: center;
  overflow: hidden;
}
.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(99, 102, 241, 0.04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(99, 102, 241, 0.04) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 60% 50% at 50% 30%, #000 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 60% 50% at 50% 30%, #000 0%, transparent 70%);
  pointer-events: none;
}
.page-hero > * { position: relative; }
.page-hero .eyebrow { margin-bottom: 18px; }
.page-hero h1 { margin-bottom: 16px; }
.page-hero .lead { max-width: 680px; margin-inline: auto; }

/* ---------- 表格 ---------- */
.tbl {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border);
  font-size: 0.92rem;
}
.tbl th, .tbl td {
  padding: 14px 18px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.tbl th {
  background: var(--bg-soft);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--fg-soft);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.tbl tbody tr:last-child td { border-bottom: none; }
.tbl tbody tr:hover { background: var(--bg-soft); }
.tbl .yes { color: var(--color-emerald); font-weight: 600; }
.tbl .no { color: var(--fg-faint); }

/* ---------- 下载卡片 ---------- */
.dl-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.dl-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.dl-icon {
  width: 56px; height: 56px;
  margin: 0 auto 14px;
  border-radius: var(--radius);
  background: var(--grad-brand-soft);
  display: grid; place-items: center;
  color: var(--color-primary);
}
.dl-icon svg { width: 28px; height: 28px; }
.dl-card h3 { margin-bottom: 4px; }
.dl-card .muted { font-size: 0.85rem; margin-bottom: 18px; }

/* ---------- 滚动动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  * { scroll-behavior: auto !important; }
}

/* ---------- 杂项 ---------- */
.divider { height: 1px; background: var(--border); border: none; margin-block: 40px; }
.kbd {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  padding: 2px 8px;
  border-radius: 6px;
  background: var(--bg-muted);
  border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  color: var(--fg-soft);
}
.prose p { margin-bottom: 16px; color: var(--fg-soft); line-height: 1.75; }
.prose h2 { margin: 32px 0 16px; }
.prose h3 { margin: 24px 0 12px; }
.prose ul { list-style: disc; padding-left: 22px; margin-bottom: 16px; display: grid; gap: 8px; color: var(--fg-soft); }
.prose ul li::marker { color: var(--color-primary); }
.prose code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--bg-muted);
  color: var(--color-primary);
}
.callout {
  border-left: 3px solid var(--color-primary);
  background: var(--grad-brand-soft);
  padding: 14px 18px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 20px 0;
  color: var(--fg-soft);
  font-size: 0.94rem;
}

/* ---------- Toast 提示 ---------- */
.toast-stack {
  position: fixed;
  top: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 12px;
  pointer-events: none;
}
.toast {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 260px;
  max-width: 400px;
  pointer-events: auto;
  opacity: 0;
  transform: translateY(-12px) scale(0.96);
  transition: opacity 0.25s ease, transform 0.25s ease;
}
.toast.show {
  opacity: 1;
  transform: translateY(0) scale(1);
}
.toast-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  flex-shrink: 0;
  font-size: 1.1rem;
}
.toast-icon.info {
  background: var(--grad-brand-soft);
  color: var(--color-primary);
}
.toast-icon.success {
  background: rgba(16, 185, 129, 0.12);
  color: var(--color-emerald);
}
.toast-icon.warning {
  background: rgba(245, 158, 11, 0.12);
  color: var(--color-amber);
}
.toast-icon.error {
  background: rgba(244, 63, 94, 0.12);
  color: var(--color-rose);
}
.toast-icon svg {
  width: 18px;
  height: 18px;
}
.toast-body {
  flex: 1;
  font-size: 0.94rem;
  font-weight: 500;
  color: var(--fg);
}
.toast-close {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: var(--fg-faint);
  flex-shrink: 0;
  transition: all 0.15s ease;
}
.toast-close:hover {
  background: var(--bg-muted);
  color: var(--fg-soft);
}
.toast-close svg {
  width: 14px;
  height: 14px;
}
@media (prefers-reduced-motion: reduce) {
  .toast, .toast.show {
    transition: none;
    opacity: 1;
    transform: none;
  }
}