/* ============================================================
   中煜（上海）科技有限公司 · 官网
   风格：Scroll Narrative · 夜空霓虹 (Night Neon)
   零外网依赖，国内访问稳定
   ============================================================ */

:root {
  /* 主色调 - 霓虹高光 */
  --indigo: #6366f1;
  --indigo-deep: #4f46e5;
  --cyan: #22d3ee;
  --teal: #5eead4;
  --pink: #f472b6;
  --rose: #fb7185;

  /* 背景层级 */
  --bg-0: #0b1020;
  --bg-1: #0f172a;
  --bg-2: #111827;

  /* 文本 */
  --text-strong: #f1f5f9;
  --text: #e5e7eb;
  --text-dim: #94a3b8;

  /* 描边 / 分隔 */
  --line: rgba(255, 255, 255, 0.10);
  --line-strong: rgba(255, 255, 255, 0.16);

  /* 容器 */
  --maxw: 1200px;
  --radius: 20px;
}

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg-0);
  color: var(--text);
  line-height: 1.7;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
h1, h2, h3, h4 { color: var(--text-strong); line-height: 1.2; font-weight: 700; }

::selection { background: rgba(99, 102, 241, 0.4); color: #fff; }

/* ---------- Layout helpers ---------- */
.shell { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.section { padding: 96px 0; position: relative; }
.section-sm { padding: 64px 0; }

.chapter-badge {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 12px; letter-spacing: 0.22em; text-transform: uppercase;
  color: #bae6fd; background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--line); border-radius: 999px;
  padding: 6px 14px;
}
.chapter-badge::before {
  content: ""; width: 6px; height: 6px; border-radius: 50%;
  background: var(--cyan); box-shadow: 0 0 10px var(--cyan);
}

.eyebrow { color: var(--teal); font-size: 13px; letter-spacing: 0.18em; text-transform: uppercase; }

h2.title {
  font-size: clamp(30px, 4.2vw, 44px);
  font-weight: 800; letter-spacing: -0.01em; margin: 18px 0 16px;
}
h2.title .grad {
  background: linear-gradient(100deg, var(--teal), var(--indigo) 55%, var(--pink));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.lead { color: var(--text-dim); font-size: clamp(15px, 1.4vw, 18px); max-width: 60ch; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 24px; border-radius: 999px; font-weight: 600; font-size: 15px;
  cursor: pointer; border: 1px solid transparent;
  transition: transform .25s ease, box-shadow .25s ease, background .25s ease;
}
.btn-primary {
  background: linear-gradient(120deg, var(--indigo), var(--indigo-deep));
  color: #fff;
  box-shadow: 0 10px 36px rgba(76, 106, 255, 0.4);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 46px rgba(76, 106, 255, 0.55); }
.btn-ghost {
  border-color: var(--line-strong); color: var(--text-strong); background: rgba(255,255,255,0.02);
}
.btn-ghost:hover { border-color: rgba(186, 230, 253, .6); background: rgba(186, 230, 253, .08); transform: translateY(-2px); }

/* ---------- Navbar ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  transition: background .3s ease, border-color .3s ease, backdrop-filter .3s ease;
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(11, 16, 32, 0.72);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  border-bottom-color: var(--line);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 16px 24px;
  display: flex; align-items: center; justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 12px; font-weight: 800; color: var(--text-strong); }
.brand-mark {
  width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--indigo), var(--cyan));
  box-shadow: 0 8px 24px rgba(34, 211, 238, .35);
  font-size: 18px; font-weight: 900; color: #0b1020;
}
.brand small { display: block; font-size: 11px; font-weight: 500; color: var(--text-dim); letter-spacing: .12em; }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { font-size: 15px; color: var(--text-dim); transition: color .2s; position: relative; }
.nav-links a:hover, .nav-links a.active { color: var(--text-strong); }
.nav-links a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -8px; height: 2px;
  background: linear-gradient(90deg, var(--teal), var(--indigo)); border-radius: 2px;
}
.nav-cta { display: flex; align-items: center; gap: 16px; }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span {
  display: block; width: 24px; height: 2px; background: var(--text-strong);
  margin: 5px 0; transition: .3s; border-radius: 2px;
}

/* ---------- Hero ---------- */
.hero { position: relative; min-height: 92vh; display: flex; align-items: center; overflow: hidden; }
.hero-bg { position: absolute; inset: -10% 0 0; z-index: 0; }
.hero-bg::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(94, 234, 212, 0.30), transparent 42%),
    radial-gradient(circle at 80% 28%, rgba(99, 102, 241, 0.34), transparent 45%),
    radial-gradient(circle at 60% 80%, rgba(244, 114, 182, 0.18), transparent 45%);
  filter: blur(40px);
}
.hero-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(circle at 50% 40%, #000 0%, transparent 75%);
  -webkit-mask-image: radial-gradient(circle at 50% 40%, #000 0%, transparent 75%);
}
.hero-content { position: relative; z-index: 2; padding-top: 120px; padding-bottom: 80px; }
.hero h1 {
  font-size: clamp(40px, 6.4vw, 68px); font-weight: 800; letter-spacing: -0.02em;
  margin: 22px 0; line-height: 1.1;
}
.hero h1 .grad {
  background: linear-gradient(100deg, var(--teal) 5%, var(--indigo) 50%, var(--pink) 95%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.hero-sub { font-size: clamp(16px, 1.6vw, 21px); color: var(--text-dim); max-width: 56ch; margin-bottom: 36px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 16px; }

.scroll-cue {
  position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
  z-index: 2; display: flex; flex-direction: column; align-items: center; gap: 8px;
  color: var(--text-dim); font-size: 12px; letter-spacing: .2em; text-transform: uppercase;
}
.scroll-cue .mouse {
  width: 24px; height: 38px; border: 1.5px solid var(--line-strong); border-radius: 14px;
  position: relative;
}
.scroll-cue .mouse::after {
  content: ""; position: absolute; top: 7px; left: 50%; transform: translateX(-50%);
  width: 4px; height: 7px; border-radius: 3px; background: var(--teal);
  animation: cue 1.6s ease-in-out infinite;
}
@keyframes cue { 0%,100%{ opacity:0; transform: translate(-50%,0);} 40%{opacity:1;} 80%{opacity:0; transform: translate(-50%,9px);} }

/* ---------- Stats strip ---------- */
.stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  padding: 48px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line);
}
.stat .num {
  font-size: clamp(30px, 3.6vw, 44px); font-weight: 800; letter-spacing: -0.01em;
  background: linear-gradient(100deg, var(--teal), var(--indigo));
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.stat .label { color: var(--text-dim); font-size: 14px; margin-top: 6px; }

/* ---------- Story beats (alternating) ---------- */
.beat {
  display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center;
  margin-bottom: 88px;
}
.beat.reverse .beat-text { order: 2; }
.beat-text h3 { font-size: clamp(24px, 2.6vw, 32px); margin: 16px 0 16px; }
.beat-text p { color: var(--text-dim); margin-bottom: 14px; }
.beat ul { list-style: none; padding: 0; margin: 20px 0 26px; }
.beat ul li { position: relative; padding-left: 28px; margin-bottom: 12px; color: var(--text); }
.beat ul li::before {
  content: ""; position: absolute; left: 0; top: 9px; width: 14px; height: 14px; border-radius: 4px;
  background: linear-gradient(135deg, var(--teal), var(--indigo));
  box-shadow: 0 0 12px rgba(34, 211, 238, .5);
}

/* ---------- Media / visual card ---------- */
.visual {
  position: relative; border-radius: var(--radius); overflow: hidden;
  background: linear-gradient(160deg, rgba(15,23,42,.9), rgba(17,24,39,.7));
  border: 1px solid var(--line);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.4);
  padding: 28px; min-height: 300px;
  display: flex; flex-direction: column; justify-content: center;
}
.visual::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 25% 20%, rgba(94,234,212,.20), transparent 45%),
    radial-gradient(circle at 80% 75%, rgba(99,102,241,.22), transparent 45%);
  filter: blur(28px); z-index: 0;
}
.visual > * { position: relative; z-index: 1; }

/* mock UI inside visual */
.mock-bar { height: 10px; border-radius: 6px; background: rgba(255,255,255,.08); margin-bottom: 10px; }
.mock-bar.w1 { width: 85%; } .mock-bar.w2 { width: 64%; } .mock-bar.w3 { width: 45%; }
.mock-row { display: flex; gap: 12px; margin-top: 18px; }
.mock-chip {
  font-size: 12px; padding: 6px 12px; border-radius: 999px;
  background: rgba(255,255,255,.06); border: 1px solid var(--line); color: var(--text-dim);
}
.mock-orb { display:flex; gap: 18px; margin-top: 22px; }
.mock-orb .o {
  width: 64px; height: 64px; border-radius: 18px;
  background: linear-gradient(135deg, rgba(94,234,212,.25), rgba(99,102,241,.25));
  border: 1px solid var(--line); display:grid; place-items:center; font-size:24px;
}
.mock-chart { display:flex; align-items:flex-end; gap: 10px; height: 120px; margin-top: 20px; }
.mock-chart i { flex:1; border-radius: 8px 8px 0 0; background: linear-gradient(180deg, var(--teal), rgba(99,102,241,.3)); }

/* ---------- Product grid ---------- */
.grid-products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.product-card {
  position: relative; border-radius: var(--radius); padding: 32px;
  background: linear-gradient(160deg, rgba(15,23,42,.85), rgba(17,24,39,.6));
  border: 1px solid var(--line); overflow: hidden;
  transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease;
}
.product-card:hover {
  transform: translateY(-6px); border-color: var(--line-strong);
  box-shadow: 0 24px 60px rgba(0,0,0,.45);
}
.product-card::after {
  content: ""; position: absolute; top: -40%; right: -30%; width: 70%; height: 70%;
  background: radial-gradient(circle, rgba(99,102,241,.18), transparent 60%);
  filter: blur(30px); opacity: 0; transition: opacity .4s;
}
.product-card:hover::after { opacity: 1; }
.product-card .icon {
  width: 52px; height: 52px; border-radius: 14px; display: grid; place-items: center; font-size: 26px;
  background: linear-gradient(135deg, rgba(94,234,212,.2), rgba(99,102,241,.22));
  border: 1px solid var(--line); margin-bottom: 20px;
}
.product-card h3 { font-size: 21px; margin-bottom: 10px; }
.product-card p { color: var(--text-dim); font-size: 15px; margin-bottom: 18px; }
.product-card .tags { display: flex; flex-wrap: wrap; gap: 8px; }
.product-card .tag {
  font-size: 12px; padding: 5px 11px; border-radius: 999px;
  background: rgba(255,255,255,.05); border: 1px solid var(--line); color: var(--text-dim);
}
.product-card.featured { grid-column: span 3; }
.product-card.featured .feat-inner {
  display: grid; grid-template-columns: 1.1fr 1fr; gap: 40px; align-items: center;
}

/* ---------- Feature list ---------- */
.features { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature { padding: 28px; border-radius: 16px; background: rgba(255,255,255,.025); border: 1px solid var(--line); }
.feature .icon { font-size: 28px; margin-bottom: 16px; }
.feature h3 { font-size: 18px; margin-bottom: 8px; }
.feature p { color: var(--text-dim); font-size: 14px; }

/* ---------- Timeline ---------- */
.timeline { position: relative; padding-left: 36px; }
.timeline::before {
  content: ""; position: absolute; left: 9px; top: 6px; bottom: 6px; width: 2px;
  background: linear-gradient(180deg, var(--teal), var(--indigo), transparent);
}
.tl-item { position: relative; padding-bottom: 40px; }
.tl-item::before {
  content: ""; position: absolute; left: -36px; top: 4px; width: 18px; height: 18px; border-radius: 50%;
  background: var(--bg-0); border: 3px solid var(--indigo);
  box-shadow: 0 0 0 5px rgba(99,102,241,.18);
}
.tl-item .year { color: var(--teal); font-weight: 700; font-size: 15px; }
.tl-item h4 { font-size: 19px; margin: 6px 0 8px; }
.tl-item p { color: var(--text-dim); }

/* ---------- CTA band ---------- */
.cta-band {
  position: relative; border-radius: 28px; overflow: hidden; padding: 64px 48px; text-align: center;
  background: linear-gradient(135deg, rgba(99,102,241,.18), rgba(34,211,238,.12));
  border: 1px solid var(--line-strong);
}
.cta-band::before {
  content:""; position:absolute; inset:0;
  background:
    radial-gradient(circle at 18% 20%, rgba(94,234,212,.28), transparent 45%),
    radial-gradient(circle at 82% 80%, rgba(244,114,182,.22), transparent 45%);
  filter: blur(40px);
}
.cta-band > * { position: relative; }
.cta-band h2 { font-size: clamp(28px, 3.6vw, 40px); margin-bottom: 14px; }
.cta-band p { color: var(--text-dim); max-width: 54ch; margin: 0 auto 28px; }
.cta-band .hero-cta { justify-content: center; }

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.contact-card {
  padding: 28px; border-radius: 16px; background: rgba(255,255,255,.025);
  border: 1px solid var(--line);
}
.contact-card h4 { font-size: 16px; margin-bottom: 14px; color: var(--text-strong); }
.contact-card .row { display:flex; gap: 14px; align-items: flex-start; padding: 10px 0; border-top: 1px solid var(--line); }
.contact-card .row:first-of-type { border-top: 0; }
.contact-card .row .ic { font-size: 18px; }
.contact-card .row .k { color: var(--text-dim); font-size: 13px; }
.contact-card .row .v { color: var(--text-strong); font-size: 15px; }

/* ---------- Footer ---------- */
.footer { border-top: 1px solid var(--line); padding: 56px 0 32px; background: var(--bg-1); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer h5 { color: var(--text-strong); font-size: 14px; margin-bottom: 16px; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer ul li { margin-bottom: 10px; }
.footer ul li a { color: var(--text-dim); font-size: 14px; transition: color .2s; }
.footer ul li a:hover { color: var(--teal); }
.footer-about p { color: var(--text-dim); font-size: 14px; margin-top: 16px; max-width: 36ch; }
.footer-bottom {
  border-top: 1px solid var(--line); padding-top: 24px;
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
  color: var(--text-dim); font-size: 13px;
}
.footer-bottom a { color: var(--text-dim); }
.footer-bottom a:hover { color: var(--teal); }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: .08s; }
.reveal.d2 { transition-delay: .16s; }
.reveal.d3 { transition-delay: .24s; }
.reveal.d4 { transition-delay: .32s; }

/* ---------- Divider with badge ---------- */
.section-divider { display:flex; align-items:center; gap:16px; margin: 0 0 56px; }
.section-divider .line { flex:1; height:1px; background: var(--line); }

/* ---------- Page hero (inner pages) ---------- */
.page-hero { position: relative; padding: 180px 0 80px; overflow: hidden; }
.page-hero .hero-bg { inset: -20% 0 0; }
.page-hero h1 { font-size: clamp(34px, 5vw, 54px); font-weight: 800; letter-spacing: -0.02em; margin: 20px 0; }
.page-hero h1 .grad {
  background: linear-gradient(100deg, var(--teal), var(--indigo), var(--pink));
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .beat, .beat.reverse .beat-text { grid-template-columns: 1fr; gap: 32px; }
  .beat.reverse .beat-text { order: 0; }
  .product-card.featured .feat-inner { grid-template-columns: 1fr; }
  .features { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .section { padding: 64px 0; }
  .nav-links, .nav-cta .btn { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex; flex-direction: column; gap: 18px; position: absolute;
    top: 100%; left: 0; right: 0; padding: 24px; background: rgba(11,16,32,.96);
    border-bottom: 1px solid var(--line); backdrop-filter: blur(14px); align-items: flex-start;
  }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .grid-products { grid-template-columns: 1fr; }
  .features { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .cta-band { padding: 44px 24px; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; }
}