/* ═══════════ 不周山科技官网 ═══════════ */
:root {
  --bg: #0b0e13;
  --bg-soft: #11151d;
  --bg-card: #151a24;
  --line: rgba(228, 214, 189, .12);
  --gold: #e4d6bd;
  --gold-deep: #c9b896;
  --text: #e9ebf0;
  --muted: #98a1af;
  --radius: 14px;
  --shadow: 0 12px 40px rgba(0, 0, 0, .35);
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", -apple-system, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ─── 导航 ─── */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: linear-gradient(180deg, rgba(8, 10, 14, .55), rgba(8, 10, 14, 0));
  transition: background .3s, box-shadow .3s, backdrop-filter .3s;
}
.nav:not(.scrolled) .nav-links a { color: #dfe3ea; text-shadow: 0 1px 10px rgba(0, 0, 0, .65); }
.nav.scrolled {
  background: rgba(11, 14, 19, .88);
  backdrop-filter: blur(14px);
  box-shadow: 0 1px 0 var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.nav-brand { color: var(--gold); font-weight: 700; font-size: 19px; letter-spacing: .14em; text-shadow: 0 1px 10px rgba(0, 0, 0, .5); }
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { font-size: 15px; color: var(--muted); transition: color .2s; }
.nav-links a:hover { color: var(--gold); }
.nav-cta {
  padding: 8px 20px; border: 1px solid var(--gold); border-radius: 999px;
  color: var(--gold) !important;
}
.nav-cta:hover { background: var(--gold); color: #14161c !important; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 24px; height: 2px; background: var(--gold); margin: 5px 0; transition: .3s; }

/* ─── 主视觉 ─── */
.hero {
  position: relative; min-height: 100vh;
  display: flex; align-items: center; justify-content: center; text-align: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background: url("../img/hero.jpg") center 38% / cover no-repeat;
  animation: heroZoom 24s ease-in-out infinite alternate;
}
@keyframes heroZoom { from { transform: scale(1); } to { transform: scale(1.09); } }
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(8, 10, 14, .62) 0%, rgba(8, 10, 14, .55) 45%, var(--bg) 100%);
}
.hero-content { position: relative; z-index: 2; padding-top: 90px; }
.hero h1 {
  font-size: clamp(30px, 5.4vw, 58px); font-weight: 700; letter-spacing: .12em;
  text-shadow: 0 4px 30px rgba(0, 0, 0, .6);
}
.hero-sub { margin: 22px auto 36px; color: #d4d9e2; font-size: clamp(15px, 1.7vw, 18px); text-shadow: 0 2px 14px rgba(0, 0, 0, .55); }
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 13px 36px; border-radius: 999px;
  font-size: 16px; letter-spacing: .06em; transition: transform .2s, box-shadow .2s, background .2s, color .2s;
}
.btn:hover { transform: translateY(-2px); }
.btn-gold { background: var(--gold); color: #14161c; font-weight: 600; box-shadow: 0 8px 28px rgba(228, 214, 189, .22); }
.btn-gold:hover { box-shadow: 0 12px 34px rgba(228, 214, 189, .34); }
.btn-ghost { border: 1px solid rgba(255, 255, 255, .45); color: #fff; }
.btn-ghost:hover { border-color: #fff; background: rgba(255, 255, 255, .08); }
.hero-scroll { position: absolute; bottom: 26px; left: 50%; transform: translateX(-50%); z-index: 2; }
.hero-scroll span {
  display: block; width: 24px; height: 38px; border: 2px solid rgba(255, 255, 255, .5); border-radius: 12px; position: relative;
}
.hero-scroll span::after {
  content: ""; position: absolute; left: 50%; top: 7px; width: 4px; height: 8px;
  background: #fff; border-radius: 2px; transform: translateX(-50%);
  animation: scrollDot 1.8s ease-in-out infinite;
}
@keyframes scrollDot { 0% { opacity: 1; top: 7px; } 70% { opacity: 0; top: 20px; } 100% { opacity: 0; } }

/* ─── 数据速览 ─── */
.stats { border-block: 1px solid var(--line); background: var(--bg-soft); }
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); }
.stat { padding: 40px 16px; text-align: center; }
.stat + .stat { border-left: 1px solid var(--line); }
.stat b { display: block; font-size: clamp(34px, 4vw, 48px); font-weight: 700; color: var(--gold); line-height: 1.1; }
.stat b::after { content: "+"; font-size: .6em; margin-left: 2px; }
.stat span { color: var(--muted); font-size: 14px; }
.stat small { font-size: 12px; opacity: .8; }

/* ─── 通用区块 ─── */
.section { padding: 96px 0; }
.section-dark { background: var(--bg-soft); }
.section-head { max-width: 760px; margin: 0 auto 56px; text-align: center; }
.section-tag {
  display: inline-block; padding: 5px 16px; margin-bottom: 16px;
  border: 1px solid var(--line); border-radius: 999px;
  color: var(--gold); font-size: 13px; letter-spacing: .2em;
}
.section-head h1, .section-head h2 { font-size: clamp(26px, 3.4vw, 38px); letter-spacing: .06em; margin-bottom: 14px; }
.section-head p { color: var(--muted); }

/* ─── 子页面头图（下载页等） ─── */
.page-hero { padding: 170px 0 90px; }
.page-hero .section-head { margin-bottom: 48px; }

/* ─── 方向支柱（AI / MR / Robot） ─── */
.pillar-feats {
  max-width: 880px; margin: 0 auto 46px;
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px 40px;
}
.pillar-feats li { position: relative; padding-left: 20px; color: #c6ccd6; font-size: 15px; }
.pillar-feats li::before { content: ""; position: absolute; left: 0; top: .68em; width: 7px; height: 7px; border-radius: 50%; background: var(--gold); }
.pillar-note { margin-top: 36px; text-align: center; color: var(--muted); font-size: 14px; }

/* ─── 产品卡片 ─── */
.prod-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.prod-grid-slim { grid-template-columns: repeat(2, 1fr); max-width: 660px; margin: 0 auto; }
.prod-card {
  background: var(--bg-card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; transition: transform .25s, border-color .25s;
}
.prod-card:hover { transform: translateY(-5px); border-color: rgba(228, 214, 189, .4); }
.prod-badge {
  display: inline-block; padding: 3px 12px; margin-bottom: 14px; border-radius: 6px;
  background: rgba(228, 214, 189, .1); color: var(--gold);
  font-size: 12px; letter-spacing: .12em;
}
.prod-card h4 { font-size: 17px; margin-bottom: 8px; }
.prod-card p { color: var(--muted); font-size: 13.5px; }
.prod-note { margin-top: 30px; text-align: center; color: var(--muted); font-size: 14px; }

/* ─── 核心能力 ─── */
.cap-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.cap-item {
  padding: 30px 28px; border: 1px solid var(--line); border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(228, 214, 189, .04), transparent 55%);
  transition: border-color .25s, transform .25s;
}
.cap-item:hover { border-color: rgba(228, 214, 189, .35); transform: translateY(-4px); }
.cap-item h4 { font-size: 17.5px; margin-bottom: 8px; color: var(--gold); }
.cap-item p { color: var(--muted); font-size: 14px; }

/* ─── 行业方案 ─── */
.sol-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.sol-card {
  display: block; background: var(--bg-card); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
  transition: transform .25s, border-color .25s, box-shadow .25s;
}
.sol-card:hover { transform: translateY(-6px); border-color: rgba(228, 214, 189, .4); box-shadow: var(--shadow); }
.sol-card img { width: 100%; height: 190px; object-fit: cover; filter: saturate(.92); transition: transform .4s; }
.sol-card:hover img { transform: scale(1.05); }
.sol-body { padding: 22px 24px 24px; }
.sol-body h3 { font-size: 19px; margin-bottom: 8px; }
.sol-body p { color: var(--muted); font-size: 14px; margin-bottom: 12px; min-height: 66px; }
.sol-more { color: var(--gold); font-size: 14px; opacity: 0; transition: opacity .25s; }
.sol-card:hover .sol-more { opacity: 1; }

/* ─── 常用下载 ─── */
.dl-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 26px; max-width: 860px; margin: 0 auto; }
.dl-card {
  background: var(--bg-card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 30px; transition: transform .25s, border-color .25s, box-shadow .25s;
}
.dl-card:hover { transform: translateY(-5px); border-color: rgba(228, 214, 189, .4); box-shadow: var(--shadow); }
.dl-card h3 { font-size: 19px; margin-bottom: 10px; }
.dl-card > p { color: var(--muted); font-size: 14px; }
.dl-meta { margin-top: 10px; font-size: 13px; color: #6d7684; }
.dl-btn { margin-top: 20px; padding: 10px 28px; font-size: 15px; }
.dl-note { margin-top: 30px; text-align: center; color: var(--muted); font-size: 14px; }

/* ─── 联系我们 ─── */
.contact-grid { max-width: 620px; margin: 0 auto; }
.contact-item { padding: 22px 0; border-bottom: 1px solid var(--line); text-align: center; }
.contact-item:last-child { border-bottom: 0; }
.contact-item h4 { font-size: 16px; margin-bottom: 4px; color: var(--gold); }
.contact-item p { color: var(--muted); font-size: 14.5px; }
.contact-item a:hover { color: var(--gold); }

/* ─── 页脚 ─── */
.footer { border-top: 1px solid var(--line); background: var(--bg-soft); padding: 56px 0 34px; text-align: center; }
.brand-name { display: block; color: var(--gold); font-size: 20px; font-weight: 700; letter-spacing: .2em; margin-bottom: 8px; }
.footer-brand p { color: var(--muted); font-size: 13px; letter-spacing: .15em; }
.footer-links { display: flex; gap: 26px; justify-content: center; margin: 26px 0; flex-wrap: wrap; }
.footer-links a { color: var(--muted); font-size: 14px; }
.footer-links a:hover { color: var(--gold); }
.footer-legal { border-top: 1px solid var(--line); padding-top: 22px; color: #6d7684; font-size: 13px; }
.footer-legal a { color: #6d7684; }
.footer-legal a:hover { color: var(--gold); }

/* ─── 动效 ─── */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero-bg { animation: none; }
}

/* ─── 响应式 ─── */
@media (max-width: 1000px) {
  .cap-grid, .sol-grid { grid-template-columns: repeat(2, 1fr); }
  .prod-grid { grid-template-columns: repeat(2, 1fr); }
  .sol-body p { min-height: 0; }
}
@media (max-width: 640px) {
  .section { padding: 66px 0; }
  .page-hero { padding: 130px 0 66px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(3) { border-left: 0; }
  .stat { border-top: 1px solid var(--line); }
  .stat:nth-child(-n+2) { border-top: 0; }
  .pillar-feats, .cap-grid, .sol-grid, .prod-grid, .prod-grid-slim, .dl-grid { grid-template-columns: 1fr; }
  .prod-grid-slim { max-width: none; }

  .nav-toggle { display: block; }
  .nav-links {
    position: fixed; top: 72px; right: 0; left: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: rgba(11, 14, 19, .97); backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
    max-height: 0; overflow: hidden; transition: max-height .35s ease;
  }
  .nav-links.open { max-height: 480px; }
  .nav-links a { padding: 15px 24px; border-top: 1px solid var(--line); }
  .nav-cta { margin: 12px 24px 18px; text-align: center; }
  .nav.open .nav-toggle span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav.open .nav-toggle span:nth-child(2) { opacity: 0; }
  .nav.open .nav-toggle span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
}