/* 龙虎斗游戏官网 - AI角色养成大模型 + AI世界事件生成大模型
   设计语言：暗色游戏引擎控制台。龙（金）与虎（赤）双色对照，辅以AI紫青做模型/数据强调色。 */

:root {
  --ink-deep: #0b0a10;
  --panel: #15131c;
  --panel-alt: #1c1926;
  --panel-raised: #231f30;
  --border: #322c40;
  --border-soft: #241f2e;
  --gold: #d9a441;
  --gold-bright: #f0c266;
  --crimson: #c0433a;
  --crimson-bright: #e2584c;
  --violet: #8b7cf6;
  --violet-dim: #6a5bc9;
  --jade: #4fbf8f;
  --white: #f3efe6;
  --muted: #a79cae;
  --muted-dim: #756a80;
  --radius: 10px;
  --radius-lg: 16px;
  --font-cjk: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Hiragino Sans GB", sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --maxw: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--ink-deep);
  color: var(--white);
  font-family: var(--font-cjk);
  line-height: 1.75;
  font-size: 16px;
  overflow-x: hidden;
  background-image:
    radial-gradient(ellipse 900px 500px at 12% -8%, rgba(217, 164, 65, 0.14), transparent 60%),
    radial-gradient(ellipse 700px 500px at 100% 8%, rgba(192, 67, 58, 0.12), transparent 60%),
    radial-gradient(ellipse 600px 420px at 50% 100%, rgba(139, 124, 246, 0.08), transparent 60%);
  background-repeat: no-repeat;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--gold-bright); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { font-weight: 700; line-height: 1.4; color: var(--white); margin: 0 0 .6em; }
p { margin: 0 0 1em; color: #d3c9d6; }
ul, ol { color: #d3c9d6; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
section { padding: 56px 0; border-top: 1px solid var(--border-soft); }
section:first-of-type { border-top: none; }
.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--gold-bright);
  text-transform: uppercase;
  background: rgba(217, 164, 65, 0.09);
  border: 1px solid rgba(217, 164, 65, 0.28);
  border-radius: 100px;
  padding: 4px 12px;
  margin-bottom: 14px;
}
.section-head { max-width: 760px; margin-bottom: 32px; }
.section-head h2 { font-size: 26px; }
.section-head p { color: var(--muted); font-size: 15px; }

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(11, 10, 16, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--white); font-weight: 700; font-size: 17px; }
.brand img { width: 30px; height: 30px; }
.nav-links { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.nav-links a {
  color: #d0c5d4; font-size: 13.5px; padding: 8px 10px; border-radius: 8px; white-space: nowrap;
}
.nav-links a:hover, .nav-links a.active { color: var(--white); background: var(--panel-raised); text-decoration: none; }
.nav-toggle {
  display: none; width: 40px; height: 40px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--panel); color: var(--white); font-size: 20px; cursor: pointer;
}
.nav-toggle span { display:block; width:18px; height:2px; background:var(--white); margin:4px auto; transition:.2s; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 11px 22px; border-radius: 8px;
  font-size: 14.5px; font-weight: 600; cursor: pointer; border: 1px solid transparent;
}
.btn-primary { background: linear-gradient(135deg, var(--gold-bright), var(--crimson-bright)); color: #1a0f08; }
.btn-primary:hover { filter: brightness(1.08); text-decoration: none; }
.btn-outline { border-color: var(--border); color: var(--white); background: var(--panel); }
.btn-outline:hover { border-color: var(--gold-bright); text-decoration: none; }
.btn-row { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 20px; }

/* ---------- Hero / Page head ---------- */
.page-head { padding-top: 40px; border-top: none; }
.page-head h1 { font-size: 29px; max-width: 760px; }
.page-head p.lead { color: var(--muted); max-width: 660px; font-size: 15.5px; }
.hero { padding-top: 64px; border-top: none; }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 40px; align-items: center; }
.hero h1 { font-size: 33px; letter-spacing: -.01em; }
.hero .lead { font-size: 16.5px; color: var(--muted); max-width: 560px; }

/* ---------- Cards / Grids ---------- */
.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.card {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 22px;
}
.card h3 { font-size: 16px; }
.card p { font-size: 14px; color: var(--muted); margin-bottom: 0; }
.card .tag {
  display: inline-block; font-family: var(--font-mono); font-size: 11px; color: var(--gold-bright);
  border: 1px solid rgba(217, 164, 65, .3); background: rgba(217, 164, 65, .08);
  padding: 2px 9px; border-radius: 100px; margin-bottom: 10px;
}

/* ---------- Concept pill row ---------- */
.pill-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.pill {
  font-family: var(--font-mono); font-size: 12px; color: var(--violet);
  border: 1px solid rgba(139, 124, 246, .3); background: rgba(139, 124, 246, .08);
  padding: 5px 11px; border-radius: 100px;
}

/* ---------- Articles ---------- */
.feature-article, .full-article {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 30px 32px; margin-bottom: 22px;
  scroll-margin-top: 90px;
}
.feature-article h3, .full-article h3 { font-size: 20px; line-height: 1.5; }
.feature-article p, .full-article p { font-size: 15px; color: #d3c9d6; }
.article-figure { margin: 20px 0; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: var(--panel-alt); }
.article-figure figcaption { font-size: 12px; color: var(--muted-dim); padding: 10px 14px; border-top: 1px solid var(--border); font-family: var(--font-mono); }

.observation-card {
  background: var(--panel-alt); border: 1px solid var(--border); border-left: 3px solid var(--crimson-bright);
  border-radius: var(--radius); padding: 22px 24px; margin-bottom: 16px;
  scroll-margin-top: 90px;
}
.observation-card h3 { font-size: 16.5px; }
.observation-card p { font-size: 14px; color: var(--muted); }

/* ---------- Related reading ---------- */
.related-reading {
  margin-top: 18px; padding-top: 16px; border-top: 1px dashed var(--border);
}
.related-reading h4 {
  font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase;
  color: var(--muted-dim); margin-bottom: 10px;
}
.related-reading ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.related-reading li { font-size: 13.5px; }
.related-reading li::before { content: "→ "; color: var(--gold-bright); }
.related-reading a { color: var(--violet); }
.related-reading a:hover { color: var(--gold-bright); }

/* ---------- Flow chain diagram ---------- */
.flow-chain { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 18px 0; }
.flow-chain .node {
  font-family: var(--font-mono); font-size: 12.5px; color: var(--white);
  background: var(--panel-alt); border: 1px solid var(--border); border-radius: 100px;
  padding: 7px 14px;
}
.flow-chain .arrow { color: var(--gold-bright); font-size: 14px; }

/* ---------- Summary rollup list ---------- */
.summary-list { display: grid; gap: 14px; }
.summary-item {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px 20px;
}
.summary-item h4 { font-size: 15px; margin-bottom: 8px; }
.summary-item p { font-size: 13.5px; color: var(--muted); margin: 0; }
.summary-item a { color: inherit; }
.summary-item a:hover h4 { color: var(--gold-bright); }
.more-link { font-size: 13px; margin-top: 6px; display: inline-block; }

/* ---------- FAQ ---------- */
.faq-list { display: grid; gap: 10px; }
.faq-item {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden;
}
.faq-q {
  margin: 0; padding: 16px 46px 16px 20px; cursor: pointer; font-size: 15px; position: relative;
  font-weight: 600; color: var(--white);
}
.faq-q::after {
  content: "+"; position: absolute; right: 18px; top: 50%; transform: translateY(-50%);
  color: var(--gold-bright); font-size: 20px; font-weight: 400;
}
.faq-item.open .faq-q::after { content: "\2212"; }
.faq-a { padding: 0 20px; max-height: 0; overflow: hidden; transition: max-height .25s ease, padding .25s ease; }
.faq-item.open .faq-a { padding: 0 20px 18px; max-height: 600px; }
.faq-a p { font-size: 14px; color: var(--muted); margin: 0; }

/* ---------- App feature grid ---------- */
.feature-list { list-style: none; margin: 20px 0 0; padding: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.feature-list li {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 14px 16px; font-size: 14.5px; color: var(--white); display: flex; gap: 10px; align-items: center;
}
.feature-list li::before {
  content: ""; width: 8px; height: 8px; border-radius: 2px; background: var(--gold-bright); flex: none;
}

.notice-box {
  background: rgba(217, 164, 65, .07); border: 1px solid rgba(217, 164, 65, .28);
  border-radius: var(--radius); padding: 18px 20px; margin: 20px 0; font-size: 14px; color: #ecdcb8;
}

/* ---------- Breadcrumb ---------- */
.breadcrumb { font-size: 13px; color: var(--muted-dim); padding: 16px 0 0; }
.breadcrumb a { color: var(--muted); }
.breadcrumb span { margin: 0 6px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--panel); border-top: 1px solid var(--border); padding: 44px 0 26px; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 30px; }
.footer-grid h4 { font-size: 13px; color: var(--muted-dim); letter-spacing: .06em; text-transform: uppercase; margin-bottom: 12px; }
.footer-grid a { display: block; color: #c7bbca; font-size: 14px; margin-bottom: 8px; }
.footer-brand { font-weight: 700; color: var(--white); font-size: 16px; margin-bottom: 8px; }
.footer-bottom {
  border-top: 1px solid var(--border); margin-top: 30px; padding-top: 20px;
  font-size: 12.5px; color: var(--muted-dim); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
}
.back-to-top {
  position: fixed; right: 22px; bottom: 22px; width: 44px; height: 44px; border-radius: 50%;
  background: var(--panel-raised); border: 1px solid var(--border); color: var(--gold-bright);
  display: none; align-items: center; justify-content: center; cursor: pointer; z-index: 90; font-size: 18px;
}
.back-to-top.show { display: flex; }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 860px) {
  .nav-links { position: fixed; top: 68px; left: 0; right: 0; bottom: 0; background: var(--ink-deep);
    flex-direction: column; align-items: stretch; padding: 16px 20px; gap: 4px;
    transform: translateX(100%); transition: transform .25s ease; overflow-y: auto; }
  .nav-links.open { transform: translateX(0); }
  .nav-links a { padding: 14px 12px; border-bottom: 1px solid var(--border-soft); border-radius: 0; font-size: 15px; }
  .nav-toggle { display: block; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 26px; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .feature-list { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  section { padding: 40px 0; }
  .feature-article, .full-article { padding: 22px 20px; }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
  .container { padding: 0 16px; }
  .flow-chain .node { font-size: 11.5px; padding: 6px 10px; }
}