/* ===========================================================
   越夏科技官网预览 · 设计系统样式
   对应文档：docs/design-system.md
   =========================================================== */

/* ---------- 1. Design Tokens ---------- */
:root {
  /* 品牌色 */
  --primary-50: #EFF5FF;
  --primary-100: #DBEAFE;
  --primary-200: #BFDBFE;
  --primary-500: #4C85FF;
  --primary-600: #1F5BFF;
  --primary-700: #1A47D6;
  --primary-900: #12307A;

  /* 强调色 */
  --accent-50: #E6F9F1;
  --accent-500: #00B578;
  --accent-600: #009E68;

  /* 中性色 */
  --ink-50: #F8FAFC;
  --ink-100: #F1F5F9;
  --ink-300: #CBD5E1;
  --ink-500: #64748B;
  --ink-700: #334155;
  --ink-900: #0B1220;

  /* 语义色 */
  --success: #16A34A;
  --warning: #F59E0B;
  --danger: #DC2626;
  --info: #0EA5E9;

  /* 主题映射（浅色） */
  --bg: #FFFFFF;
  --bg-subtle: var(--ink-50);
  --surface: #FFFFFF;
  --surface-2: var(--ink-50);
  --border: var(--ink-100);
  --border-strong: var(--ink-300);
  --text: var(--ink-700);
  --heading: var(--ink-900);
  --muted: var(--ink-500);
  --link: var(--primary-600);

  /* 圆角 */
  --r-sm: 6px;
  --r: 8px;
  --r-md: 12px;
  --r-lg: 16px;
  --r-xl: 24px;
  --r-full: 9999px;

  /* 阴影 */
  --sh-xs: 0 1px 2px rgba(11, 18, 32, .05);
  --sh-sm: 0 1px 3px rgba(11, 18, 32, .08), 0 1px 2px rgba(11, 18, 32, .04);
  --sh-md: 0 4px 12px rgba(11, 18, 32, .08);
  --sh-lg: 0 12px 32px rgba(11, 18, 32, .10);
  --sh-xl: 0 24px 64px rgba(11, 18, 32, .12);
  --sh-focus: 0 0 0 3px rgba(31, 91, 255, .35);

  /* 布局 */
  --container: 1200px;
  --gutter: 32px;
  --section: 96px;
  --section-sm: 56px;

  /* 动效 */
  --ease: cubic-bezier(.22, 1, .36, 1);
  --t-fast: 150ms;
  --t: 200ms;
  --t-slow: 400ms;
}

/* 深色模式 */
.dark {
  --bg: #0B1220;
  --bg-subtle: #0F1729;
  --surface: #131C31;
  --surface-2: #1A2440;
  --border: #26314F;
  --border-strong: #33405F;
  --text: #94A3B8;
  --heading: #E2E8F0;
  --muted: #7C8AA5;
  --link: #5B8CFF;
  --primary-600: #5B8CFF;
  --primary-700: #7CA3FF;
  --primary-50: #16233F;
  --primary-100: #1B2E52;
  --ink-100: #1A2440;
  --ink-50: #131C31;
  --sh-sm: 0 1px 3px rgba(0, 0, 0, .4);
  --sh-md: 0 4px 12px rgba(0, 0, 0, .45);
  --sh-lg: 0 12px 32px rgba(0, 0, 0, .5);
  --sh-xl: 0 24px 64px rgba(0, 0, 0, .55);
}

/* ---------- 2. Reset & Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
               "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, h4 { color: var(--heading); margin: 0; font-weight: 600; letter-spacing: -.01em; }
p { margin: 0; }
a { color: var(--link); text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; }
input, textarea, select { font: inherit; color: inherit; }
ul { margin: 0; padding: 0; list-style: none; }

:where(a, button, input, textarea, summary):focus-visible {
  outline: none;
  box-shadow: var(--sh-focus);
  border-radius: var(--r-sm);
}

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.prose { max-width: 720px; }

/* ---------- 3. Typography ---------- */
.t-display { font-size: 56px; line-height: 1.1; letter-spacing: -.02em; font-weight: 700; }
.t-h1 { font-size: 40px; line-height: 1.2; letter-spacing: -.01em; font-weight: 700; }
.t-h2 { font-size: 32px; line-height: 1.3; font-weight: 600; }
.t-h3 { font-size: 24px; line-height: 1.4; font-weight: 600; }
.t-h4 { font-size: 20px; line-height: 1.5; font-weight: 600; }
.t-lg { font-size: 18px; line-height: 1.75; }
.t-sm { font-size: 14px; line-height: 1.7; }
.t-cap { font-size: 13px; line-height: 1.6; }
.muted { color: var(--muted); }

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; letter-spacing: .06em; text-transform: uppercase;
  color: var(--primary-600);
}
.eyebrow::before {
  content: ""; width: 20px; height: 2px; border-radius: 2px;
  background: var(--primary-600);
}

/* ---------- 4. Layout ---------- */
.section { padding-block: var(--section); }
.section--subtle { background: var(--bg-subtle); }
.section--tight { padding-block: 64px; }
@media (max-width: 768px) {
  :root { --section: 56px; --gutter: 20px; }
  .section--tight { padding-block: 48px; }
  .t-display { font-size: 32px; }
  .t-h1 { font-size: 28px; }
  .t-h2 { font-size: 24px; }
  .t-h3 { font-size: 20px; }
  .t-h4 { font-size: 18px; }
}

.section-head { max-width: 720px; margin-bottom: 56px; }
.section-head--center { margin-inline: auto; text-align: center; }
.section-head .t-h2 { margin-top: 16px; }
.section-head p { margin-top: 16px; font-size: 18px; color: var(--muted); }
@media (max-width: 768px) { .section-head { margin-bottom: 36px; } }

.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: 1024px) { .grid--4 { grid-template-columns: repeat(2, 1fr); } .grid--3 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; } }

/* ---------- 5. Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 44px; padding-inline: 20px;
  border: 1px solid transparent; border-radius: var(--r);
  font-size: 15px; font-weight: 600; white-space: nowrap;
  transition: background var(--t-fast) var(--ease), color var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease), transform var(--t) var(--ease),
              box-shadow var(--t) var(--ease);
}
.btn svg { width: 18px; height: 18px; }
.btn--lg { height: 48px; padding-inline: 26px; font-size: 16px; }
.btn--sm { height: 32px; padding-inline: 14px; font-size: 14px; }
.btn--primary { background: var(--primary-600); color: #fff; box-shadow: var(--sh-sm); }
.btn--primary:hover { background: var(--primary-700); transform: translateY(-1px); box-shadow: var(--sh-md); }
.btn--secondary { background: var(--surface); color: var(--heading); border-color: var(--border-strong); }
.btn--secondary:hover { border-color: var(--primary-600); color: var(--primary-600); }
.btn--accent { background: var(--accent-500); color: #fff; }
.btn--accent:hover { background: var(--accent-600); transform: translateY(-1px); }
.btn--ghost { background: transparent; color: var(--primary-600); }
.btn--ghost:hover { background: var(--primary-50); }
.btn[disabled] { opacity: .5; cursor: not-allowed; transform: none; }
.btn-group { display: flex; flex-wrap: wrap; gap: 12px; }

/* ---------- 6. Header & Nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: var(--bg);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.site-header.is-scrolled { border-bottom-color: var(--border); box-shadow: var(--sh-sm); }
.header-inner {
  display: flex; align-items: center; gap: 32px;
  height: 72px;
  transition: height var(--t) var(--ease);
}
.site-header.is-scrolled .header-inner { height: 60px; }

.brand { display: flex; align-items: center; gap: 10px; font-size: 18px; font-weight: 700; color: var(--heading); }
.brand-mark {
  width: 32px; height: 32px; border-radius: 9px; flex: none;
  background: linear-gradient(135deg, var(--primary-600), var(--primary-500));
  display: grid; place-items: center; color: #fff; font-size: 15px; font-weight: 800;
  box-shadow: var(--sh-sm);
}

.nav { display: flex; align-items: center; gap: 4px; margin-right: auto; }
.nav-link {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 8px 12px; border-radius: var(--r);
  font-size: 15px; font-weight: 500; color: var(--text);
  transition: color var(--t-fast) var(--ease), background var(--t-fast) var(--ease);
}
.nav-link:hover, .nav-item:hover > .nav-link { color: var(--primary-600); background: var(--primary-50); }
.nav-link.is-active { color: var(--primary-600); }
.nav-link .chev { width: 14px; height: 14px; }
.nav-item { position: relative; }

.header-actions { display: flex; align-items: center; gap: 8px; }
.icon-btn {
  width: 38px; height: 38px; display: grid; place-items: center;
  background: transparent; border: 1px solid transparent; border-radius: var(--r);
  color: var(--muted);
  transition: color var(--t-fast) var(--ease), background var(--t-fast) var(--ease);
}
.icon-btn:hover { color: var(--heading); background: var(--surface-2); }
.icon-btn svg { width: 18px; height: 18px; }
.lang-switch { display: flex; align-items: center; gap: 2px; font-size: 14px; color: var(--muted); }
.lang-switch button { background: none; border: 0; padding: 4px 6px; border-radius: var(--r-sm); color: var(--muted); }
.lang-switch button.is-active { color: var(--primary-600); font-weight: 600; }
.menu-toggle { display: none; }

/* Megamenu */
.mega {
  position: absolute; top: 100%; left: -12px; width: 620px;
  padding: 20px; display: grid; grid-template-columns: 1fr 1fr; gap: 8px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-lg);
  box-shadow: var(--sh-lg);
  opacity: 0; visibility: hidden; transform: translateY(-6px);
  transition: opacity var(--t) var(--ease), transform var(--t) var(--ease), visibility var(--t);
}
.nav-item:hover .mega { opacity: 1; visibility: visible; transform: translateY(0); }
.mega-item { display: flex; gap: 12px; padding: 12px; border-radius: var(--r-md); transition: background var(--t-fast) var(--ease); }
.mega-item:hover { background: var(--surface-2); }
.mega-ico {
  width: 36px; height: 36px; flex: none; border-radius: 9px; display: grid; place-items: center;
  background: var(--primary-50); color: var(--primary-600);
}
.mega-ico svg { width: 18px; height: 18px; }
.mega-item strong { display: block; color: var(--heading); font-size: 15px; font-weight: 600; }
.mega-item span { font-size: 13px; line-height: 1.5; color: var(--muted); }

/* Mobile drawer */
@media (max-width: 1024px) {
  .nav { display: none; }
  .menu-toggle { display: grid; }
  .lang-switch { display: none; }
  .nav.is-open {
    display: block; position: fixed; inset: 72px 0 auto; max-height: calc(100vh - 72px);
    overflow-y: auto; padding: 16px var(--gutter) 24px;
    background: var(--bg); border-bottom: 1px solid var(--border); box-shadow: var(--sh-lg);
  }
  .nav.is-open .nav-link { display: block; padding: 14px 8px; font-size: 16px; }
  .nav.is-open .mega { position: static; width: auto; opacity: 1; visibility: visible; transform: none;
    grid-template-columns: 1fr; box-shadow: none; border: 0; padding: 4px 0 8px 12px; }
  .nav.is-open .btn { margin-top: 12px; width: 100%; }
}

/* ---------- 7. Hero ---------- */
.hero { position: relative; padding-block: 96px 80px; overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: -140px 0 auto; height: 620px; z-index: -1;
  background:
    radial-gradient(600px 300px at 15% 0%, rgba(31, 91, 255, .12), transparent 70%),
    radial-gradient(500px 260px at 85% 10%, rgba(0, 181, 120, .10), transparent 70%);
  pointer-events: none;
}
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }
.hero h1 { margin-top: 20px; }
.hero-sub { margin-top: 20px; font-size: 18px; color: var(--muted); max-width: 520px; }
.hero .btn-group { margin-top: 32px; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 24px; margin-top: 32px; }
.hero-meta li { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--muted); }
.hero-meta svg { width: 16px; height: 16px; color: var(--accent-500); }
@media (max-width: 1024px) {
  .hero { padding-block: 56px; }
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
}

/* 产品截图占位（纯 CSS 应用窗口） */
.app-window {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-lg);
  box-shadow: var(--sh-xl); overflow: hidden;
}
.app-bar { display: flex; align-items: center; gap: 6px; height: 40px; padding-inline: 14px; background: var(--surface-2); border-bottom: 1px solid var(--border); }
.app-bar i { width: 10px; height: 10px; border-radius: 50%; background: var(--border-strong); }
.app-bar span { margin-left: 10px; font-size: 12px; color: var(--muted); }
.app-body { display: grid; grid-template-columns: 148px 1fr; min-height: 300px; }
.app-side { padding: 16px 12px; border-right: 1px solid var(--border); background: var(--surface-2); display: grid; gap: 10px; align-content: start; }
.app-side i { display: block; height: 10px; border-radius: var(--r-sm); background: var(--border); }
.app-side i:nth-child(1) { background: var(--primary-200); width: 70%; }
.app-main { padding: 18px; display: grid; gap: 14px; align-content: start; }
.app-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.app-stat { padding: 12px; border: 1px solid var(--border); border-radius: var(--r-md); }
.app-stat b { display: block; font-size: 20px; color: var(--heading); font-variant-numeric: tabular-nums; }
.app-stat span { font-size: 11px; color: var(--muted); }
.app-chart { height: 110px; border: 1px solid var(--border); border-radius: var(--r-md); padding: 14px;
  display: flex; align-items: flex-end; gap: 8px; }
.app-chart i { flex: 1; border-radius: 4px 4px 0 0; background: linear-gradient(180deg, var(--primary-500), var(--primary-50)); }
.dark .app-chart i { background: linear-gradient(180deg, var(--primary-600), var(--primary-900)); }
.app-chart i:nth-child(2) { height: 45%; } .app-chart i:nth-child(3) { height: 70%; }
.app-chart i:nth-child(4) { height: 55%; } .app-chart i:nth-child(5) { height: 90%; }
.app-chart i:nth-child(6) { height: 65%; }
@media (max-width: 520px) { .app-body { grid-template-columns: 1fr; } .app-side { display: none; } }

/* ---------- 8. Logo wall ---------- */
.logo-wall { overflow: hidden; -webkit-mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); }
.logo-track { display: flex; gap: 64px; width: max-content; animation: marquee 34s linear infinite; }
.logo-wall:hover .logo-track { animation-play-state: paused; }
.logo-track span {
  font-size: 19px; font-weight: 700; letter-spacing: .02em; color: var(--ink-500);
  filter: grayscale(1); opacity: .6; transition: filter var(--t) var(--ease), opacity var(--t) var(--ease), color var(--t) var(--ease);
}
.logo-track span:hover { filter: grayscale(0); opacity: 1; color: var(--heading); }
@keyframes marquee { to { transform: translateX(-50%); } }

/* ---------- 9. Cards ---------- */
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-lg);
  padding: 28px; box-shadow: var(--sh-sm);
  transition: transform var(--t) var(--ease), box-shadow var(--t) var(--ease), border-color var(--t) var(--ease);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--sh-md); border-color: var(--primary-200); }
.card-ico {
  width: 44px; height: 44px; border-radius: var(--r-md); display: grid; place-items: center;
  background: var(--primary-50); color: var(--primary-600); margin-bottom: 18px;
}
.card-ico svg { width: 22px; height: 22px; }
.card h3 { font-size: 20px; }
.card p { margin-top: 10px; font-size: 15px; color: var(--muted); }
.card-link { display: inline-flex; align-items: center; gap: 6px; margin-top: 18px; font-size: 14px; font-weight: 600; color: var(--primary-600); }
.card-link svg { width: 16px; height: 16px; transition: transform var(--t) var(--ease); }
.card:hover .card-link svg { transform: translateX(3px); }

.tag {
  display: inline-flex; align-items: center; height: 24px; padding-inline: 10px;
  border-radius: var(--r-sm); font-size: 13px; font-weight: 500;
  background: var(--primary-50); color: var(--primary-700);
}
.tag--outline { background: transparent; border: 1px solid var(--border-strong); color: var(--muted); }
.tag--success { background: var(--accent-50); color: var(--accent-600); }

/* ---------- 10. Tabs ---------- */
.tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 32px; }
.tab {
  height: 40px; padding-inline: 18px; border-radius: var(--r-full);
  background: var(--surface); border: 1px solid var(--border-strong);
  color: var(--text); font-size: 15px; font-weight: 500;
  transition: all var(--t-fast) var(--ease);
}
.tab:hover { border-color: var(--primary-600); color: var(--primary-600); }
.tab.is-active { background: var(--primary-600); border-color: var(--primary-600); color: #fff; }
.tab-panel { display: none; }
.tab-panel.is-active { display: block; animation: fadeUp var(--t-slow) var(--ease); }
@keyframes fadeUp { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }

.solution-panel { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; }
.solution-panel ul { margin-top: 24px; display: grid; gap: 14px; }
.solution-panel li { display: flex; gap: 12px; align-items: flex-start; }
.solution-panel li svg { width: 20px; height: 20px; flex: none; margin-top: 3px; color: var(--accent-500); }
.solution-visual {
  aspect-ratio: 4 / 3; border-radius: var(--r-lg); border: 1px solid var(--border);
  background:
    radial-gradient(300px 200px at 30% 20%, rgba(31, 91, 255, .16), transparent 70%),
    radial-gradient(280px 200px at 75% 80%, rgba(0, 181, 120, .14), transparent 70%),
    var(--surface-2);
  display: grid; place-items: center; box-shadow: var(--sh-md);
}
.solution-visual span { font-size: 13px; color: var(--muted); }
@media (max-width: 1024px) { .solution-panel { grid-template-columns: 1fr; gap: 32px; } }

/* ---------- 11. Cases ---------- */
.case-card { display: flex; flex-direction: column; overflow: hidden; padding: 0; }
.case-cover { height: 132px; display: grid; place-items: center; border-bottom: 1px solid var(--border);
  background: linear-gradient(135deg, var(--primary-50), var(--surface-2)); }
.case-cover span { font-size: 17px; font-weight: 700; color: var(--primary-900); letter-spacing: .04em; }
.dark .case-cover span { color: var(--primary-700); }
.case-body { padding: 24px; display: flex; flex-direction: column; flex: 1; }
.case-body h3 { font-size: 18px; }
.case-body > p { margin-top: 10px; font-size: 14px; color: var(--muted); }
.case-metrics { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 20px; padding-top: 20px; border-top: 1px solid var(--border); }
.case-metrics div b { display: block; font-size: 22px; color: var(--primary-600); font-variant-numeric: tabular-nums; }
.case-metrics div span { font-size: 12px; color: var(--muted); }
.case-body .card-link { margin-top: auto; }

/* ---------- 12. Stats ---------- */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.stat { text-align: center; }
.stat b { display: block; font-size: 44px; line-height: 1.1; color: var(--heading); font-variant-numeric: tabular-nums; }
.stat span { display: block; margin-top: 8px; font-size: 14px; color: var(--muted); }
@media (max-width: 768px) { .stats { grid-template-columns: repeat(2, 1fr); gap: 32px 16px; } .stat b { font-size: 32px; } }

/* ---------- 13. Blog ---------- */
.post-card { display: flex; flex-direction: column; padding: 0; overflow: hidden; }
.post-cover { height: 150px; background: linear-gradient(135deg, var(--primary-100), var(--surface-2)); border-bottom: 1px solid var(--border); }
.post-body { padding: 24px; display: flex; flex-direction: column; flex: 1; gap: 10px; }
.post-meta { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--muted); }
.post-body h3 { font-size: 18px; line-height: 1.45; }
.post-body p { font-size: 14px; color: var(--muted); }
.post-body .card-link { margin-top: auto; }

/* ---------- 14. CTA & Form ---------- */
.cta-band {
  position: relative; overflow: hidden;
  padding: 64px; border-radius: var(--r-xl);
  background: linear-gradient(120deg, var(--primary-900), var(--primary-600) 65%, var(--primary-500));
  color: #fff;
}
.cta-band::after {
  content: ""; position: absolute; width: 420px; height: 420px; right: -120px; top: -160px;
  background: radial-gradient(circle, rgba(255, 255, 255, .16), transparent 65%);
}
.cta-band h2, .cta-band p { color: #fff; }
.cta-band p { margin-top: 14px; opacity: .85; }
.cta-band-inner { position: relative; z-index: 1; display: grid; grid-template-columns: 1fr 420px; gap: 48px; align-items: center; }
@media (max-width: 1024px) { .cta-band { padding: 36px 24px; } .cta-band-inner { grid-template-columns: 1fr; gap: 32px; } }

.form-card { background: var(--surface); border-radius: var(--r-lg); padding: 28px; box-shadow: var(--sh-xl); }
.form-card h3 { font-size: 20px; margin-bottom: 4px; }
.form-card .muted { font-size: 14px; }
.field { display: grid; gap: 6px; margin-top: 16px; }
.field label { font-size: 14px; font-weight: 500; color: var(--heading); }
.field label i { color: var(--danger); font-style: normal; }
.field input, .field textarea, .field select {
  width: 100%; min-height: 44px; padding: 10px 14px;
  background: var(--surface); border: 1px solid var(--border-strong); border-radius: var(--r);
  transition: border-color var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease);
}
.field textarea { min-height: 96px; resize: vertical; }
.field input:focus, .field textarea:focus, .field select:focus { outline: none; border-color: var(--primary-600); box-shadow: var(--sh-focus); }
.field input::placeholder, .field textarea::placeholder { color: var(--ink-500); opacity: .7; }
.field .err { font-size: 13px; color: var(--danger); display: none; }
.field.has-error input, .field.has-error textarea { border-color: var(--danger); }
.field.has-error .err { display: block; }
.checkbox { display: flex; gap: 10px; align-items: flex-start; margin-top: 18px; font-size: 13px; color: var(--muted); }
.checkbox input { width: 16px; height: 16px; margin-top: 3px; accent-color: var(--primary-600); }
.checkbox a { color: var(--primary-600); }
.form-card .btn { width: 100%; margin-top: 20px; }
.form-success { display: none; text-align: center; padding: 24px 0; }
.form-success.show { display: block; animation: fadeUp var(--t-slow) var(--ease); }
.form-success .ok { width: 56px; height: 56px; margin: 0 auto 16px; border-radius: 50%; display: grid; place-items: center;
  background: var(--accent-50); color: var(--accent-600); }
.form-success .ok svg { width: 28px; height: 28px; }

/* ---------- 15. Breadcrumb ---------- */
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); padding-block: 24px; }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--primary-600); }
.breadcrumb svg { width: 14px; height: 14px; }

/* ---------- 16. Product page ---------- */
.product-hero { padding-block: 24px 72px; }
.product-hero-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
@media (max-width: 1024px) { .product-hero-grid { grid-template-columns: 1fr; gap: 36px; } }

.feature-row { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.feature-row + .feature-row { margin-top: 80px; }
.feature-row:nth-child(even) .feature-visual { order: -1; }
.feature-visual {
  aspect-ratio: 16 / 10; border-radius: var(--r-lg); border: 1px solid var(--border);
  background: radial-gradient(340px 220px at 30% 25%, rgba(31, 91, 255, .14), transparent 70%), var(--surface-2);
  display: grid; place-items: center; box-shadow: var(--sh-md);
}
.feature-visual span { font-size: 13px; color: var(--muted); }
.feature-list { margin-top: 24px; display: grid; gap: 14px; }
.feature-list li { display: flex; gap: 12px; }
.feature-list svg { width: 20px; height: 20px; flex: none; margin-top: 3px; color: var(--accent-500); }
@media (max-width: 1024px) {
  .feature-row { grid-template-columns: 1fr; gap: 28px; }
  .feature-row:nth-child(even) .feature-visual { order: 0; }
  .feature-row + .feature-row { margin-top: 56px; }
}

.arch-box {
  border: 1px solid var(--border); border-radius: var(--r-lg); background: var(--surface-2);
  padding: 40px; box-shadow: var(--sh-sm);
}
.arch-diagram { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.arch-node {
  padding: 18px; border: 1px solid var(--border-strong); border-radius: var(--r-md);
  background: var(--surface); text-align: center; font-size: 14px; font-weight: 600; color: var(--heading);
}
.arch-node small { display: block; margin-top: 4px; font-size: 12px; font-weight: 400; color: var(--muted); }
.arch-flow { display: grid; place-items: center; padding-block: 16px; color: var(--primary-600); font-size: 13px; }
@media (max-width: 768px) { .arch-diagram { grid-template-columns: 1fr; } }

.integration-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; }
.integration-item {
  aspect-ratio: 1; border: 1px solid var(--border); border-radius: var(--r-md); background: var(--surface);
  display: grid; place-items: center; font-size: 13px; color: var(--muted);
  transition: border-color var(--t) var(--ease), color var(--t) var(--ease), transform var(--t) var(--ease);
}
.integration-item:hover { border-color: var(--primary-600); color: var(--primary-600); transform: translateY(-2px); }
@media (max-width: 1024px) { .integration-grid { grid-template-columns: repeat(4, 1fr); } }
@media (max-width: 640px) { .integration-grid { grid-template-columns: repeat(3, 1fr); } }

.cert-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }

/* FAQ */
.faq { display: grid; gap: 12px; max-width: 860px; }
.faq details {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-md);
  transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.faq details[open] { border-color: var(--primary-200); box-shadow: var(--sh-sm); }
.faq summary {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 18px 20px; cursor: pointer; list-style: none;
  font-size: 16px; font-weight: 600; color: var(--heading);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary .plus { width: 20px; height: 20px; flex: none; color: var(--primary-600); transition: transform var(--t) var(--ease); }
.faq details[open] summary .plus { transform: rotate(45deg); }
.faq .answer { padding: 0 20px 20px; font-size: 15px; color: var(--muted); }

/* Inline CTA strip */
.cta-strip {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 20px;
  padding: 32px 36px; border-radius: var(--r-lg);
  background: var(--primary-50); border: 1px solid var(--primary-100);
}
.cta-strip h3 { font-size: 20px; }
.cta-strip p { font-size: 14px; color: var(--muted); margin-top: 4px; }

/* Spec table */
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--r-lg); }
table { width: 100%; border-collapse: collapse; min-width: 640px; }
th, td { padding: 16px 20px; text-align: left; border-bottom: 1px solid var(--border); font-size: 15px; }
th { background: var(--surface-2); font-size: 13px; color: var(--muted); font-weight: 600; }
tbody tr:last-child td { border-bottom: 0; }
td:not(:first-child) { text-align: center; }
th:not(:first-child) { text-align: center; }
.yes { color: var(--accent-600); font-weight: 600; }
.no { color: var(--ink-300); }

/* ---------- 17. Contact page ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 380px; gap: 48px; align-items: start; }
@media (max-width: 1024px) { .contact-grid { grid-template-columns: 1fr; gap: 32px; } }
.info-card { padding: 24px; border: 1px solid var(--border); border-radius: var(--r-lg); background: var(--surface); box-shadow: var(--sh-sm); }
.info-card + .info-card { margin-top: 16px; }
.info-card h3 { font-size: 16px; margin-bottom: 12px; }
.info-card li { display: flex; gap: 12px; padding-block: 10px; font-size: 15px; border-top: 1px solid var(--border); }
.info-card li:first-child { border-top: 0; }
.info-card li svg { width: 18px; height: 18px; flex: none; margin-top: 3px; color: var(--primary-600); }
.qr-box { width: 132px; height: 132px; border-radius: var(--r-md); border: 1px solid var(--border); display: grid; place-items: center;
  background: var(--surface-2); font-size: 12px; color: var(--muted); text-align: center; }
.contact-hero { padding-block: 72px 8px; }
.contact-aside { display: grid; gap: 16px; }
.contact-aside .info-card + .info-card { margin-top: 0; }
.info-card-ico { width: 40px; height: 40px; border-radius: var(--r); display: grid; place-items: center;
  background: var(--primary-50); color: var(--primary-600); margin-bottom: 14px; }
.info-card-ico svg { width: 20px; height: 20px; }
.info-card h4 { font-size: 16px; margin-bottom: 0; }
.info-card p { margin-top: 6px; font-size: 14px; color: var(--muted); }
.info-card .feature-list { margin-top: 12px; }
.info-card .feature-list li { border-top: 0; padding-block: 6px; font-size: 14px; }
.topics-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
@media (max-width: 1024px) { .topics-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .topics-grid { grid-template-columns: 1fr; } }
.topic { padding: 28px; border: 1px solid var(--border); border-radius: var(--r-lg); background: var(--surface); box-shadow: var(--sh-sm); }
.topic h4 { display: flex; align-items: center; gap: 10px; font-size: 16px; }
.topic h4 svg { width: 20px; height: 20px; color: var(--primary-600); flex: none; }
.topic p { margin-top: 10px; font-size: 14px; color: var(--muted); }
.topic a { display: inline-flex; align-items: center; gap: 6px; margin-top: 16px; font-size: 14px; color: var(--primary-600); }
.map-card { border: 1px solid var(--border); border-radius: var(--r-lg); overflow: hidden; background: var(--surface); }

/* ---------- 18. Footer ---------- */
.site-footer { background: var(--bg-subtle); border-top: 1px solid var(--border); padding-block: 64px 32px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr repeat(4, 1fr); gap: 40px; }
.footer-brand p { margin-top: 16px; font-size: 14px; color: var(--muted); max-width: 280px; }
.footer-col h4 { font-size: 14px; margin-bottom: 16px; }
.footer-col li + li { margin-top: 10px; }
.footer-col a { font-size: 14px; color: var(--muted); transition: color var(--t-fast) var(--ease); }
.footer-col a:hover { color: var(--primary-600); }
.socials { display: flex; gap: 8px; margin-top: 20px; }
.socials a { width: 36px; height: 36px; display: grid; place-items: center; border: 1px solid var(--border); border-radius: var(--r); color: var(--muted); }
.socials a:hover { border-color: var(--primary-600); color: var(--primary-600); }
.socials svg { width: 17px; height: 17px; }
.footer-bottom {
  display: flex; flex-wrap: wrap; gap: 12px; justify-content: space-between; align-items: center;
  margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--border); font-size: 13px; color: var(--muted);
}
.footer-bottom nav { display: flex; gap: 20px; flex-wrap: wrap; }
@media (max-width: 1024px) { .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; } }
@media (max-width: 640px) { .footer-grid { grid-template-columns: 1fr; } }

/* ---------- 19. Utilities & Animation ---------- */
.ic { width: 1em; height: 1em; flex: none; }
.reveal { opacity: 0; transform: translateY(16px); transition: opacity var(--t-slow) var(--ease), transform var(--t-slow) var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }
.divider { height: 1px; background: var(--border); border: 0; margin: 0; }
.text-center { text-align: center; }
.mt-32 { margin-top: 32px; }
.mt-48 { margin-top: 48px; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
  html { scroll-behavior: auto; }
}

/* 浮动咨询条 */
.floating-cta {
  position: fixed; right: 20px; bottom: 24px; z-index: 40;
  display: grid; gap: 10px;
}
.floating-cta button {
  width: 48px; height: 48px; border-radius: 50%; border: 0;
  background: var(--surface); color: var(--primary-600); box-shadow: var(--sh-lg);
  display: grid; place-items: center;
  transition: transform var(--t) var(--ease), background var(--t) var(--ease);
}
.floating-cta button:hover { transform: translateY(-2px); background: var(--primary-600); color: #fff; }
.floating-cta svg { width: 20px; height: 20px; }
.floating-cta .to-top { color: var(--muted); }
@media (max-width: 768px) { .floating-cta .to-top, .floating-cta .chat { display: none; } }

/* ---------- 跳转链接（键盘与读屏用户直达正文） ---------- */
.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 100;
  padding: 10px 16px;
  border-radius: 8px;
  background: var(--primary-600);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  transition: top 150ms ease-out;
}
.skip-link:focus { top: 12px; }
@media (prefers-reduced-motion: reduce) { .skip-link { transition: none; } }