/* 问鼎娱乐官网 - 3D生成式AI大模型官方网站样式
   配色：暖白 / 深石墨蓝 / 3D科技青 / 紫 / 游戏橙 / 中性灰 */

:root {
  --c-warm-white: #f6f4ef;
  --c-paper: #fbfaf7;
  --c-graphite: #0f1521;
  --c-graphite-2: #161d2d;
  --c-graphite-3: #1e2740;
  --c-cyan: #2fd6c8;
  --c-cyan-dim: #1aa89c;
  --c-purple: #8b7ff0;
  --c-orange: #f2884d;
  --c-gray-900: #1c2130;
  --c-gray-700: #3c4356;
  --c-gray-500: #6b7284;
  --c-gray-300: #b7bcc9;
  --c-gray-100: #e7e5df;
  --c-border: #e1ddd2;
  --c-border-dark: #29314a;
  --shadow-soft: 0 8px 28px rgba(15, 21, 33, 0.08);
  --shadow-card: 0 2px 10px rgba(15, 21, 33, 0.06);
  --radius: 14px;
  --radius-sm: 8px;
  --maxw: 1180px;
  --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Courier New", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--c-warm-white);
  color: var(--c-gray-900);
  font-family: var(--font-sans);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { padding-left: 1.3em; }
h1, h2, h3, h4 { line-height: 1.36; margin: 0 0 .6em; font-weight: 700; letter-spacing: .01em; }
p { margin: 0 0 1em; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
section { padding: 72px 0; }
.section-tight { padding: 48px 0; }

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 700; letter-spacing: .08em;
  color: var(--c-cyan-dim); text-transform: uppercase;
  margin-bottom: 14px;
}
.eyebrow::before { content: ""; width: 20px; height: 2px; background: var(--c-cyan); display: inline-block; }

.section-head { max-width: 760px; margin-bottom: 40px; }
.section-head h2 { font-size: clamp(24px, 3.2vw, 34px); color: var(--c-graphite); }
.section-head p { color: var(--c-gray-700); font-size: 16px; }

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(246, 244, 239, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--c-border);
}
.nav-wrap {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 19px; color: var(--c-graphite); }
.brand .logo-mark { width: 34px; height: 34px; }
.brand small { display: block; font-size: 11px; font-weight: 500; color: var(--c-gray-500); letter-spacing: .04em; }
.main-nav { display: flex; gap: 4px; }
.main-nav a {
  padding: 9px 14px; font-size: 14.5px; font-weight: 600; color: var(--c-gray-700);
  border-radius: 999px; transition: background .15s, color .15s;
  white-space: nowrap;
}
.main-nav a:hover, .main-nav a[aria-current="page"] { background: var(--c-graphite); color: var(--c-warm-white); }
.nav-cta {
  padding: 9px 18px; border-radius: 999px; background: var(--c-cyan); color: var(--c-graphite) !important;
  font-weight: 800; font-size: 14px;
}
.nav-cta:hover { background: var(--c-cyan-dim); color: var(--c-warm-white) !important; }
.menu-toggle {
  display: none; background: none; border: 1px solid var(--c-border); border-radius: 8px;
  width: 40px; height: 40px; cursor: pointer; position: relative;
}
.menu-toggle span, .menu-toggle span::before, .menu-toggle span::after {
  content: ""; position: absolute; left: 9px; right: 9px; height: 2px; background: var(--c-graphite);
}
.menu-toggle span { top: 19px; }
.menu-toggle span::before { top: -6px; }
.menu-toggle span::after { top: 6px; }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(160deg, var(--c-graphite) 0%, var(--c-graphite-2) 55%, var(--c-graphite-3) 100%);
  color: var(--c-warm-white);
  padding: 64px 0 56px;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(circle at 82% 12%, rgba(47,214,200,.18), transparent 45%),
              radial-gradient(circle at 8% 90%, rgba(139,127,240,.16), transparent 40%);
  pointer-events: none;
}
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 48px; align-items: center; position: relative; }
.hero-eyebrow { color: var(--c-cyan); font-size: 13px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; margin-bottom: 18px; }
.hero h1 { font-size: clamp(28px, 4vw, 42px); color: #fff; margin-bottom: 18px; }
.hero .lede { color: var(--c-gray-300); font-size: 16.5px; max-width: 620px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 22px 0 26px; }
.hero-tags span { border: 1px solid var(--c-border-dark); color: var(--c-gray-300); font-size: 12.5px; padding: 5px 12px; border-radius: 999px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 12px 22px; border-radius: 999px;
  font-weight: 800; font-size: 14.5px; cursor: pointer; border: 1px solid transparent;
}
.btn-primary { background: var(--c-cyan); color: var(--c-graphite); }
.btn-primary:hover { background: #58e6da; }
.btn-ghost { background: transparent; border-color: var(--c-border-dark); color: #fff; }
.btn-ghost:hover { border-color: var(--c-cyan); color: var(--c-cyan); }
.hero-art { background: #fff; border: 1px solid var(--c-border-dark); border-radius: var(--radius); padding: 14px; }
.hero-art svg { width: 100%; height: auto; }
.hero-art figcaption { font-size: 12px; color: var(--c-gray-500); margin-top: 10px; text-align: center; }

/* ---------- Frontier / trend cards ---------- */
.trend-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.trend-card {
  background: var(--c-paper); border: 1px solid var(--c-border); border-radius: var(--radius);
  padding: 20px; box-shadow: var(--shadow-card);
}
.trend-card .tag { font-size: 11.5px; font-weight: 800; color: var(--c-cyan-dim); text-transform: uppercase; letter-spacing: .06em; }
.trend-card h3 { font-size: 16px; margin: 8px 0 8px; color: var(--c-graphite); }
.trend-card p { font-size: 13.8px; color: var(--c-gray-700); margin: 0; }

/* ---------- Pipeline strip ---------- */
.pipeline-section { background: var(--c-graphite); color: var(--c-warm-white); }
.pipeline-section .section-head h2 { color: #fff; }
.pipeline-section .section-head p { color: var(--c-gray-300); }
.pipeline-figure { background: #fff; border: 1px solid var(--c-border-dark); border-radius: var(--radius); padding: 20px; }
.pipeline-figure svg { width: 100%; height: auto; }
.pipeline-figure figcaption { color: var(--c-gray-500); font-size: 13px; margin-top: 12px; text-align: center; }
.concept-split { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 28px; }
.concept-card { background: rgba(255,255,255,.04); border: 1px solid var(--c-border-dark); border-radius: var(--radius); padding: 22px; }
.concept-card h4 { color: var(--c-cyan); font-size: 15px; margin-bottom: 10px; }
.concept-card p { color: var(--c-gray-300); font-size: 14.5px; margin: 0; }
.concept-card.alt h4 { color: var(--c-orange); }

/* ---------- Article blocks (核心长文) ---------- */
.article-block {
  background: var(--c-paper); border: 1px solid var(--c-border); border-radius: var(--radius);
  padding: 32px; margin-bottom: 22px; box-shadow: var(--shadow-card);
}
.article-block .art-meta { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.art-index {
  width: 30px; height: 30px; border-radius: 8px; background: var(--c-graphite); color: var(--c-cyan);
  display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 13px; flex-shrink: 0;
}
.art-cat { font-size: 12.5px; font-weight: 800; color: var(--c-cyan-dim); text-transform: uppercase; letter-spacing: .04em; }
.article-block h3 { font-size: clamp(18px, 2.2vw, 22px); color: var(--c-graphite); margin-bottom: 14px; }
.article-block .art-figure { margin: 18px 0; border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 14px; background: #fff; }
.article-block .art-figure svg { width: 100%; height: auto; }
.article-block .art-figure figcaption { font-size: 12.5px; color: var(--c-gray-500); margin-top: 8px; text-align: center; }
.article-block .art-body p { color: var(--c-gray-700); font-size: 15.3px; }
.article-block .art-body p:first-of-type { font-size: 16px; color: var(--c-gray-900); }

/* ---------- Observation column ---------- */
.observe-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.observe-card {
  background: var(--c-graphite-2); color: var(--c-gray-300); border-radius: var(--radius);
  padding: 24px; border: 1px solid var(--c-border-dark);
}
.observe-card .tag { font-size: 11.5px; color: var(--c-orange); font-weight: 800; text-transform: uppercase; letter-spacing: .06em; }
.observe-card h3 { color: #fff; font-size: 16.5px; margin: 10px 0 12px; }
.observe-card p { font-size: 14px; margin: 0; }

/* ---------- Sub-article summary rollup cards (index.html 21篇) ---------- */
.rollup-section { background: var(--c-graphite-3); }
.rollup-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 28px; }
.rollup-tab {
  padding: 9px 16px; border-radius: 999px; border: 1px solid var(--c-border-dark);
  color: var(--c-gray-300); font-size: 13.5px; font-weight: 700; cursor: pointer; background: transparent;
}
.rollup-tab.active, .rollup-tab:hover { background: var(--c-cyan); color: var(--c-graphite); border-color: var(--c-cyan); }
.rollup-group { display: none; margin-bottom: 34px; }
.rollup-group.active { display: block; }
.rollup-group-head { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 14px; flex-wrap: wrap; gap: 8px; }
.rollup-group-head h3 { color: #fff; font-size: 18px; margin: 0; }
.rollup-group-head a { color: var(--c-cyan); font-size: 13.5px; font-weight: 700; }
.rollup-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.rollup-card {
  background: rgba(255,255,255,.035); border: 1px solid var(--c-border-dark); border-radius: var(--radius);
  padding: 20px; display: flex; flex-direction: column; height: 100%;
}
.rollup-card h4 { color: #fff; font-size: 15px; margin-bottom: 10px; }
.rollup-card p { color: var(--c-gray-300); font-size: 13.6px; flex: 1; margin: 0 0 14px; }
.rollup-card .read-link { color: var(--c-cyan); font-size: 13px; font-weight: 800; }

/* ---------- FAQ ---------- */
.faq-list { border-top: 1px solid var(--c-border); }
.faq-item { border-bottom: 1px solid var(--c-border); }
.faq-q {
  width: 100%; text-align: left; background: none; border: none; cursor: pointer;
  padding: 18px 4px; font-size: 15.5px; font-weight: 700; color: var(--c-graphite);
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
}
.faq-q .icon { flex-shrink: 0; width: 20px; height: 20px; position: relative; }
.faq-q .icon::before, .faq-q .icon::after { content: ""; position: absolute; background: var(--c-cyan-dim); transition: transform .2s; }
.faq-q .icon::before { top: 9px; left: 2px; right: 2px; height: 2px; }
.faq-q .icon::after { left: 9px; top: 2px; bottom: 2px; width: 2px; }
.faq-item.open .faq-q .icon::after { transform: scaleY(0); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .25s ease; }
.faq-item.open .faq-a { max-height: 400px; }
.faq-a p { padding: 0 4px 18px; color: var(--c-gray-700); font-size: 14.6px; margin: 0; }

/* ---------- About ---------- */
.about-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.about-wrap .art-body p { color: var(--c-gray-700); font-size: 15.3px; }
.about-facts { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.fact-card { background: var(--c-paper); border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 16px; }
.fact-card .k { font-size: 12px; color: var(--c-gray-500); font-weight: 700; }
.fact-card .v { font-size: 14.5px; color: var(--c-graphite); font-weight: 700; margin-top: 4px; }

/* ---------- Term glossary chips ---------- */
.term-grid { display: flex; flex-wrap: wrap; gap: 10px; }
.term-chip { border: 1px solid var(--c-border); border-radius: 999px; padding: 8px 14px; font-size: 13px; color: var(--c-gray-700); background: var(--c-paper); }
.term-chip b { color: var(--c-graphite); }

/* ---------- Page hero (subpages) ---------- */
.page-hero { background: linear-gradient(160deg, var(--c-graphite) 0%, var(--c-graphite-2) 60%, var(--c-graphite-3) 100%); color: #fff; padding: 52px 0 46px; }
.breadcrumb { font-size: 13px; color: var(--c-gray-500); margin-bottom: 16px; }
.breadcrumb a { color: var(--c-gray-300); }
.breadcrumb a:hover { color: var(--c-cyan); }
.page-hero h1 { font-size: clamp(26px, 3.6vw, 36px); color: #fff; }
.page-hero .lede { color: var(--c-gray-300); font-size: 16px; max-width: 700px; }

/* ---------- Concept overview list (subpages) ---------- */
.qa-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.qa-card { background: var(--c-paper); border: 1px solid var(--c-border); border-radius: var(--radius-sm); padding: 18px; }
.qa-card .q { font-size: 13.5px; font-weight: 800; color: var(--c-cyan-dim); margin-bottom: 6px; }
.qa-card .a { font-size: 13.8px; color: var(--c-gray-700); margin: 0; }

/* ---------- App function grid ---------- */
.func-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.func-card { background: var(--c-paper); border: 1px solid var(--c-border); border-radius: var(--radius); padding: 20px; }
.func-num { font-family: var(--font-mono); font-size: 12px; color: var(--c-cyan-dim); font-weight: 800; }
.func-card h4 { font-size: 15.5px; margin: 8px 0 6px; color: var(--c-graphite); }
.func-card p { font-size: 13.4px; color: var(--c-gray-700); margin: 0; }

/* ---------- Footer ---------- */
.site-footer { background: var(--c-graphite); color: var(--c-gray-300); padding: 56px 0 26px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 36px; }
.footer-brand { font-weight: 800; font-size: 18px; color: #fff; margin-bottom: 10px; }
.footer-desc { font-size: 13.6px; color: var(--c-gray-500); max-width: 320px; }
.footer-col h5 { font-size: 13px; color: #fff; text-transform: uppercase; letter-spacing: .05em; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 13.8px; color: var(--c-gray-300); margin-bottom: 10px; }
.footer-col a:hover { color: var(--c-cyan); }
.footer-bottom { border-top: 1px solid var(--c-border-dark); padding-top: 22px; font-size: 12.6px; color: var(--c-gray-500); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }
.footer-bottom .company-line { color: var(--c-gray-300); }

/* ---------- Back to top ---------- */
.back-top {
  position: fixed; right: 22px; bottom: 22px; width: 44px; height: 44px; border-radius: 50%;
  background: var(--c-graphite); color: var(--c-cyan); border: 1px solid var(--c-border-dark);
  display: flex; align-items: center; justify-content: center; cursor: pointer; opacity: 0; pointer-events: none;
  transition: opacity .2s; z-index: 90; box-shadow: var(--shadow-soft);
}
.back-top.show { opacity: 1; pointer-events: auto; }

/* ---------- Misc ---------- */
.divider { height: 1px; background: var(--c-border); margin: 0; }
.badge-list { display: flex; flex-wrap: wrap; gap: 8px; }
.badge { font-size: 12px; padding: 4px 10px; border-radius: 999px; background: var(--c-gray-100); color: var(--c-gray-700); }
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.center { text-align: center; }
.mt-lg { margin-top: 40px; }

/* ---------- Table scroll wrapper ---------- */
.table-scroll { overflow-x: auto; border: 1px solid var(--c-border); border-radius: var(--radius-sm); }
.table-scroll table { border-collapse: collapse; width: 100%; min-width: 560px; font-size: 13.6px; }
.table-scroll th, .table-scroll td { padding: 12px 14px; text-align: left; border-bottom: 1px solid var(--c-border); }
.table-scroll th { background: var(--c-gray-100); color: var(--c-graphite); font-weight: 800; }
.table-scroll td { color: var(--c-gray-700); }

/* ================= Responsive ================= */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; }
  .trend-grid { grid-template-columns: repeat(2, 1fr); }
  .rollup-cards { grid-template-columns: repeat(2, 1fr); }
  .qa-grid { grid-template-columns: repeat(2, 1fr); }
  .func-grid { grid-template-columns: repeat(2, 1fr); }
  .observe-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .about-wrap { grid-template-columns: 1fr; }
  .two-col { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .main-nav { display: none; }
  .menu-toggle { display: block; }
  .main-nav.mobile-open {
    display: flex; flex-direction: column; position: absolute; top: 68px; left: 0; right: 0;
    background: var(--c-warm-white); border-bottom: 1px solid var(--c-border); padding: 10px 24px 18px; gap: 2px;
  }
  .main-nav.mobile-open a { padding: 12px 6px; border-bottom: 1px solid var(--c-border); border-radius: 0; }
  section { padding: 48px 0; }
  .trend-grid { grid-template-columns: 1fr; }
  .rollup-cards { grid-template-columns: 1fr; }
  .qa-grid { grid-template-columns: 1fr; }
  .func-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .article-block { padding: 22px; }
  .hero { padding: 40px 0 36px; }
  .footer-bottom { flex-direction: column; }
}