/* ===== Design tokens ===== */
:root {
  --bg: #ffffff;
  --bg-soft: #f7f9fc;
  --bg-elev: #ffffff;
  --text: #0b1220;
  --text-muted: #5b6779;
  --line: #e6eaf0;
  --line-soft: #eef1f6;
  --brand: #1a56db;
  --brand-2: #06a3c9;
  --brand-soft: #eef3ff;
  --shadow: 0 1px 2px rgba(11, 18, 32, .04), 0 12px 32px rgba(11, 18, 32, .06);
  --shadow-lg: 0 2px 4px rgba(11, 18, 32, .05), 0 24px 60px rgba(11, 18, 32, .10);
  --r-sm: 10px;
  --r-md: 16px;
  --r-lg: 24px;
  --maxw: 1160px;
  --ease: cubic-bezier(.22, .8, .3, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0e17;
    --bg-soft: #0e1420;
    --bg-elev: #121a28;
    --text: #eaf0f9;
    --text-muted: #93a1b8;
    --line: #1e2838;
    --line-soft: #18202e;
    --brand: #6d9bff;
    --brand-2: #35c8e8;
    --brand-soft: #131f38;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 12px 32px rgba(0, 0, 0, .35);
    --shadow-lg: 0 2px 4px rgba(0, 0, 0, .35), 0 24px 60px rgba(0, 0, 0, .5);
  }
}

/* ===== Base ===== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system,
    BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { margin: 0; line-height: 1.25; letter-spacing: -0.02em; font-weight: 700; }
p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }

.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 24px; }
.section { padding: clamp(64px, 9vw, 116px) 0; }
.section--soft { background: var(--bg-soft); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 46px; padding: 0 22px;
  border-radius: 999px; border: 1px solid transparent;
  font-size: 15px; font-weight: 600; white-space: nowrap;
  cursor: pointer;
  transition: transform .25s var(--ease), background .25s var(--ease),
              border-color .25s var(--ease), box-shadow .25s var(--ease), opacity .25s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }
.btn--primary {
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
  color: #fff;
  box-shadow: 0 8px 24px -8px color-mix(in srgb, var(--brand) 70%, transparent);
}
.btn--primary:hover { box-shadow: 0 14px 34px -10px color-mix(in srgb, var(--brand) 75%, transparent); }
.btn--ghost { background: var(--bg-elev); color: var(--text); border-color: var(--line); }
.btn--ghost:hover { border-color: color-mix(in srgb, var(--brand) 45%, var(--line)); }
.btn--sm { height: 38px; padding: 0 18px; font-size: 14px; }

/* ===== Header ===== */
.header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s var(--ease), background .3s var(--ease);
}
.header.is-stuck { border-bottom-color: var(--line); }
.header__inner { display: flex; align-items: center; gap: 24px; height: 68px; }

.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: -0.01em; }
.logo__mark {
  width: 32px; height: 32px; border-radius: 9px; flex: none;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  display: grid; place-items: center;
  box-shadow: 0 6px 16px -6px color-mix(in srgb, var(--brand) 80%, transparent);
}
.logo__mark svg { width: 18px; height: 18px; }
.logo__text { font-size: 17px; }
.logo__text span { color: var(--text-muted); font-weight: 500; font-size: 12px; letter-spacing: .14em; display: block; margin-top: -4px; }

.nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav a {
  padding: 8px 14px; border-radius: 999px;
  font-size: 15px; color: var(--text-muted);
  transition: color .2s var(--ease), background .2s var(--ease);
}
.nav a:hover { color: var(--text); background: var(--bg-soft); }
.header__cta { margin-left: 8px; }

.burger {
  display: none; margin-left: auto;
  width: 42px; height: 42px; border-radius: 12px;
  border: 1px solid var(--line); background: var(--bg-elev);
  cursor: pointer; place-items: center; color: var(--text);
}
.burger svg { width: 20px; height: 20px; }

/* ===== Hero ===== */
.hero { position: relative; overflow: hidden; padding: clamp(72px, 10vw, 132px) 0 clamp(56px, 7vw, 92px); }
.hero__glow {
  position: absolute; inset: -20% -10% auto -10%; height: 620px; pointer-events: none; z-index: 0;
  background:
    radial-gradient(48% 52% at 22% 32%, color-mix(in srgb, var(--brand) 22%, transparent), transparent 68%),
    radial-gradient(42% 48% at 78% 18%, color-mix(in srgb, var(--brand-2) 20%, transparent), transparent 66%);
  filter: blur(8px);
}
.hero__grid-bg {
  position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background-image: linear-gradient(var(--line-soft) 1px, transparent 1px),
                    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(70% 60% at 50% 30%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 60% at 50% 30%, #000 0%, transparent 78%);
  opacity: .75;
}
.hero .wrap { position: relative; z-index: 1; }
.hero__inner { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(32px, 5vw, 72px); align-items: center; }

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px 6px 8px; border-radius: 999px;
  background: var(--brand-soft); border: 1px solid color-mix(in srgb, var(--brand) 18%, transparent);
  color: color-mix(in srgb, var(--brand) 88%, var(--text));
  font-size: 13px; font-weight: 600; letter-spacing: .01em;
}
.eyebrow b {
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
  color: #fff; font-size: 11px; font-weight: 700; letter-spacing: .06em;
  padding: 2px 9px; border-radius: 999px;
}
.hero h1 {
  margin: 22px 0 0;
  font-size: clamp(34px, 5.2vw, 58px);
  letter-spacing: -0.035em;
}
.hero h1 .grad {
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero__lead { margin-top: 20px; font-size: clamp(16px, 1.35vw, 18px); color: var(--text-muted); max-width: 52ch; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.hero__note { margin-top: 18px; font-size: 13.5px; color: var(--text-muted); display: flex; align-items: center; gap: 8px; }
.hero__note svg { width: 16px; height: 16px; color: var(--brand); flex: none; }

/* Hero visual */
.rack {
  position: relative; border-radius: var(--r-lg);
  background: var(--bg-elev); border: 1px solid var(--line);
  box-shadow: var(--shadow-lg); padding: 20px;
}
.rack__bar { display: flex; align-items: center; gap: 8px; padding-bottom: 16px; border-bottom: 1px solid var(--line-soft); }
.rack__dot { width: 10px; height: 10px; border-radius: 50%; background: var(--line); }
.rack__dot:first-child { background: color-mix(in srgb, var(--brand) 70%, transparent); }
.rack__title { margin-left: 6px; font-size: 12.5px; color: var(--text-muted); letter-spacing: .06em; }
.rack__title b { color: var(--text); font-weight: 600; }
.rack__body { display: grid; gap: 10px; margin-top: 16px; }
.unit {
  display: grid; grid-template-columns: 26px 1fr auto; align-items: center; gap: 12px;
  padding: 12px 14px; border-radius: var(--r-sm);
  background: var(--bg-soft); border: 1px solid var(--line-soft);
}
.unit__leds { display: flex; gap: 4px; }
.unit__leds i {
  width: 5px; height: 5px; border-radius: 50%; display: block;
  background: color-mix(in srgb, var(--brand-2) 85%, transparent);
  animation: blink 2.4s var(--ease) infinite;
}
.unit__leds i:nth-child(2) { animation-delay: .5s; background: color-mix(in srgb, var(--brand) 80%, transparent); }
.unit__leds i:nth-child(3) { animation-delay: 1.1s; }
@keyframes blink { 0%, 100% { opacity: 1; } 45% { opacity: .25; } }
.unit__name { font-size: 13.5px; font-weight: 600; }
.unit__meta { font-size: 12px; color: var(--text-muted); font-variant-numeric: tabular-nums; }
.meter { height: 5px; border-radius: 999px; background: var(--line); overflow: hidden; margin-top: 6px; }
.meter > i { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--brand), var(--brand-2)); }
.rack__foot {
  display: flex; justify-content: space-between; align-items: center;
  margin-top: 16px; padding-top: 14px; border-top: 1px solid var(--line-soft);
  font-size: 12.5px; color: var(--text-muted);
}
.pill-live { display: inline-flex; align-items: center; gap: 7px; font-weight: 600; color: var(--text); }
.pill-live::before {
  content: ""; width: 7px; height: 7px; border-radius: 50%; background: #16b364;
  box-shadow: 0 0 0 3px color-mix(in srgb, #16b364 22%, transparent);
}

/* ===== Stats ===== */
.stats { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--bg-soft); }
.stats__grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { padding: 34px 24px; text-align: center; border-left: 1px solid var(--line); }
.stat:first-child { border-left: 0; }
.stat__num {
  font-size: clamp(26px, 3vw, 36px); font-weight: 700; letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.stat__label { margin-top: 4px; font-size: 13.5px; color: var(--text-muted); }

/* ===== Section head ===== */
.head { max-width: 640px; margin-bottom: clamp(36px, 4.5vw, 56px); }
.head--center { margin-inline: auto; text-align: center; }
.head__tag {
  font-size: 13px; font-weight: 700; letter-spacing: .16em; text-transform: uppercase;
  color: var(--brand);
}
.head h2 { margin-top: 12px; font-size: clamp(26px, 3.4vw, 40px); }
.head p { margin-top: 14px; color: var(--text-muted); font-size: 16.5px; }

/* ===== Cards ===== */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card {
  position: relative; padding: 30px 28px 28px;
  background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--r-md);
  transition: transform .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease);
}
.card::after {
  content: ""; position: absolute; inset: 0; border-radius: inherit; pointer-events: none;
  background: linear-gradient(140deg, color-mix(in srgb, var(--brand) 7%, transparent), transparent 46%);
  opacity: 0; transition: opacity .35s var(--ease);
}
.card:hover { transform: translateY(-4px); border-color: color-mix(in srgb, var(--brand) 34%, var(--line)); box-shadow: var(--shadow); }
.card:hover::after { opacity: 1; }
.card__icon {
  width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center;
  background: var(--brand-soft); color: var(--brand);
  border: 1px solid color-mix(in srgb, var(--brand) 14%, transparent);
}
.card__icon svg { width: 22px; height: 22px; }
.card h3 { margin-top: 20px; font-size: 18.5px; }
.card p { margin-top: 10px; color: var(--text-muted); font-size: 15px; }
.card__list { margin-top: 16px; display: grid; gap: 7px; }
.card__list li { position: relative; padding-left: 20px; font-size: 14px; color: var(--text-muted); }
.card__list li::before {
  content: ""; position: absolute; left: 4px; top: 10px;
  width: 5px; height: 5px; border-radius: 50%;
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
}

/* ===== Feature split ===== */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(32px, 5vw, 72px); align-items: center; }
.feats { display: grid; gap: 8px; }
.feat {
  display: grid; grid-template-columns: 40px 1fr; gap: 16px;
  padding: 18px; border-radius: var(--r-md);
  border: 1px solid transparent;
  transition: background .3s var(--ease), border-color .3s var(--ease);
}
.feat:hover { background: var(--bg-elev); border-color: var(--line); }
.feat__ic {
  width: 40px; height: 40px; border-radius: 11px; display: grid; place-items: center;
  background: var(--brand-soft); color: var(--brand);
}
.feat__ic svg { width: 20px; height: 20px; }
.feat h4 { font-size: 16.5px; }
.feat p { margin-top: 6px; color: var(--text-muted); font-size: 14.5px; }

.panel {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--r-lg); padding: 28px; box-shadow: var(--shadow);
}
.panel__row { display: flex; justify-content: space-between; align-items: baseline; gap: 16px; padding: 15px 0; border-top: 1px solid var(--line-soft); }
.panel__row:first-of-type { border-top: 0; padding-top: 4px; }
.panel__k { font-size: 14.5px; color: var(--text-muted); }
.panel__v { font-size: 15px; font-weight: 700; font-variant-numeric: tabular-nums; }
.panel__head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 18px; }
.panel__head h3 { font-size: 17px; }
.badge {
  font-size: 12px; font-weight: 600; padding: 4px 11px; border-radius: 999px;
  background: var(--brand-soft); color: var(--brand);
  border: 1px solid color-mix(in srgb, var(--brand) 16%, transparent);
}

/* ===== Solutions ===== */
.sols { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.sol {
  padding: 26px 22px; border-radius: var(--r-md);
  background: var(--bg-elev); border: 1px solid var(--line);
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), border-color .35s var(--ease);
}
.sol:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: color-mix(in srgb, var(--brand) 30%, var(--line)); }
.sol__ic { width: 38px; height: 38px; border-radius: 11px; display: grid; place-items: center; background: var(--brand-soft); color: var(--brand); }
.sol__ic svg { width: 19px; height: 19px; }
.sol h4 { margin-top: 16px; font-size: 16.5px; }
.sol p { margin-top: 8px; font-size: 14px; color: var(--text-muted); }

/* ===== Steps ===== */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; counter-reset: step; }
.step { position: relative; padding-top: 26px; border-top: 2px solid var(--line); }
.step::before {
  counter-increment: step; content: "0" counter(step);
  position: absolute; top: -1px; left: 0; transform: translateY(-50%);
  font-size: 12px; font-weight: 700; letter-spacing: .08em;
  color: var(--brand); background: var(--bg); padding-right: 12px;
}
.section--soft .step::before { background: var(--bg-soft); }
.step h4 { font-size: 16.5px; }
.step p { margin-top: 8px; font-size: 14.5px; color: var(--text-muted); }

/* ===== CTA ===== */
.cta {
  position: relative; overflow: hidden;
  border-radius: var(--r-lg); padding: clamp(40px, 6vw, 68px);
  background: linear-gradient(125deg, #0f2557, #10406e 46%, #0a6e86);
  color: #fff; text-align: center;
  box-shadow: var(--shadow-lg);
}
.cta::before {
  content: ""; position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.06) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.06) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(64% 70% at 50% 0%, #000, transparent 76%);
  -webkit-mask-image: radial-gradient(64% 70% at 50% 0%, #000, transparent 76%);
}
.cta > * { position: relative; }
.cta h2 { font-size: clamp(24px, 3.2vw, 38px); }
.cta p { margin-top: 14px; color: rgba(255, 255, 255, .78); font-size: 16.5px; }
.cta__actions { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 30px; }
.cta .btn--primary { background: #fff; color: #0f2557; box-shadow: 0 12px 34px -12px rgba(0,0,0,.6); }
.cta .btn--ghost { background: rgba(255,255,255,.07); color: #fff; border-color: rgba(255,255,255,.3); }
.cta .btn--ghost:hover { background: rgba(255,255,255,.14); border-color: rgba(255,255,255,.5); }

/* ===== Contact ===== */
.contact { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.contact__item {
  padding: 26px; border-radius: var(--r-md);
  background: var(--bg-elev); border: 1px solid var(--line);
}
.contact__item .card__icon { width: 40px; height: 40px; border-radius: 11px; }
.contact__item .card__icon svg { width: 19px; height: 19px; }
.contact__item h4 { margin-top: 16px; font-size: 15px; color: var(--text-muted); font-weight: 600; }
.contact__item p { margin-top: 6px; font-size: 17px; font-weight: 700; letter-spacing: -0.01em; }
.contact__item span { display: block; margin-top: 6px; font-size: 13.5px; color: var(--text-muted); font-weight: 400; }
.contact__item .addr { font-size: 15.5px; line-height: 1.6; letter-spacing: 0; }

/* ===== Footer ===== */
.footer { border-top: 1px solid var(--line); padding: 56px 0 32px; background: var(--bg-soft); }
.footer__top { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; }
.footer__about p { margin-top: 16px; color: var(--text-muted); font-size: 14.5px; max-width: 34ch; }
.footer__col h5 { font-size: 14px; font-weight: 700; margin: 0 0 14px; }
.footer__col a { display: block; padding: 5px 0; font-size: 14.5px; color: var(--text-muted); transition: color .2s var(--ease); }
.footer__col a:hover { color: var(--brand); }
.footer__bottom {
  margin-top: 44px; padding-top: 22px; border-top: 1px solid var(--line);
  display: flex; flex-wrap: wrap; gap: 10px 20px; justify-content: space-between;
  font-size: 13.5px; color: var(--text-muted);
}
.footer__bottom a:hover { color: var(--brand); }

/* ===== Reveal ===== */
/* 隐藏态仅在 JS 可用时生效，避免脚本失效导致内容不可见 */
.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.js .reveal.is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition-duration: .01ms !important; }
  .js .reveal { opacity: 1; transform: none; }
  html { scroll-behavior: auto; }
}

/* ===== Responsive ===== */
@media (max-width: 1000px) {
  .cards, .sols, .steps, .contact { grid-template-columns: repeat(2, 1fr); }
  .footer__top { grid-template-columns: 1fr 1fr; gap: 32px; }
}
@media (max-width: 860px) {
  .nav, .header__cta { display: none; }
  .burger { display: grid; }
  .header.is-open .nav {
    display: flex; flex-direction: column; align-items: stretch; gap: 2px;
    position: absolute; left: 16px; right: 16px; top: 66px;
    padding: 10px; border-radius: var(--r-md);
    background: var(--bg-elev); border: 1px solid var(--line); box-shadow: var(--shadow-lg);
  }
  .header.is-open .nav a { padding: 12px 14px; color: var(--text); }
  .hero__inner, .split { grid-template-columns: 1fr; }
  .hero__visual { order: -1; }
  .stats__grid { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(3) { border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--line); }
}
@media (max-width: 560px) {
  .wrap { padding-inline: 18px; }
  .cards, .sols, .steps, .contact, .footer__top { grid-template-columns: 1fr; }
  .hero__actions .btn, .cta__actions .btn { flex: 1 1 100%; }
  .step { padding-top: 22px; }
}