/* AI 前沿 · AI Frontier — 共享样式（同域，无外部 CDN） */
:root{
  --bg:#0A1120; --bg2:#0D1730; --surface:rgba(148,163,184,.07); --surface2:rgba(148,163,184,.12);
  --line:rgba(148,163,184,.16); --line2:rgba(148,163,184,.26);
  --text:#E6EDF7; --muted:#93A4BD; --faint:#64748B;
  --accent:#22D3EE; --blue:#60A5FA; --violet:#818CF8; --amber:#FBBF24; --green:#34D399; --pink:#F472B6;
  --radius:14px; --maxw:1180px;
  --font-disp:"Space Grotesk","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"PingFang SC","Microsoft YaHei","Hiragino Sans GB",system-ui,sans-serif;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:15px;line-height:1.75;-webkit-font-smoothing:antialiased;overflow-x:hidden}
::selection{background:rgba(34,211,238,.28)}
a{color:inherit;text-decoration:none}
img,svg{max-width:100%}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}

.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ===== 导航 ===== */
.nav{position:sticky;top:0;z-index:60;background:rgba(10,17,32,.92);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.nav-in{max-width:var(--maxw);margin:0 auto;padding:0 20px;height:62px;display:flex;align-items:center;gap:24px;overflow-x:auto}
.brand{display:flex;align-items:center;gap:9px;font-weight:700;font-size:1.08rem;color:#fff;white-space:nowrap}
.brand .en{color:var(--muted);font-weight:500;font-size:.8rem}
.nav-links{display:flex;gap:2px;margin-left:auto}
.nav-link{padding:7px 13px;border-radius:9px;color:var(--muted);font-size:.92rem;transition:.2s;white-space:nowrap}
.nav-link:hover{color:var(--text);background:var(--surface)}
.nav-link.active{color:var(--accent);background:rgba(34,211,238,.1)}
@media(max-width:720px){.brand .en{display:none}.nav-links{gap:0}.nav-link{padding:7px 9px;font-size:.86rem}}

/* ===== Hero ===== */
.hero{position:relative;padding:74px 0 56px;overflow:hidden;background:radial-gradient(880px 440px at 78% -10%,rgba(34,211,238,.15),transparent 60%),radial-gradient(740px 400px at 10% 6%,rgba(129,140,248,.15),transparent 60%),var(--bg)}
.hero::before{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(148,163,184,.06) 1px,transparent 1px),linear-gradient(90deg,rgba(148,163,184,.06) 1px,transparent 1px);background-size:44px 44px;mask-image:radial-gradient(700px 400px at 50% 0%,#000 30%,transparent 75%);-webkit-mask-image:radial-gradient(700px 400px at 50% 0%,#000 30%,transparent 75%);pointer-events:none}
.hero-in{position:relative;z-index:1}
.hero-tag{display:inline-flex;align-items:center;gap:8px;padding:6px 14px;border:1px solid var(--line2);border-radius:999px;background:var(--surface);color:var(--accent);font-size:.83rem;margin-bottom:20px}
.hero h1{font-size:clamp(1.9rem,4.6vw,3rem);font-weight:700;line-height:1.2;letter-spacing:-.01em;max-width:20em}
.hero h1 .hl{background:linear-gradient(100deg,var(--accent),var(--blue) 55%,var(--violet));-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p.lead{color:var(--muted);font-size:clamp(.98rem,1.9vw,1.1rem);max-width:36em;margin:16px 0 0;font-weight:300}
.hero-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-top:40px}
.stat{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:15px 17px}
.stat b{display:block;font-size:1.5rem;font-weight:700;color:#fff;line-height:1.3}
.stat b i{font-style:normal;font-size:.85rem;color:var(--muted);font-weight:500}
.stat span{color:var(--muted);font-size:.8rem}
@media(max-width:720px){.hero-stats{grid-template-columns:repeat(2,1fr)}}

/* ===== 区块 ===== */
.section{padding:52px 0}
.sec-head{margin:0 0 24px}
.sec-head h2{font-size:clamp(1.35rem,3vw,1.9rem);font-weight:700;letter-spacing:.01em}
.sec-head .sub{color:var(--muted);font-size:.9rem;margin-top:6px}
.sec-head h2::before{content:"";display:inline-block;width:4px;height:.95em;background:var(--accent);border-radius:2px;margin-right:10px;vertical-align:-.12em}

/* ===== 卡片网格 ===== */
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:15px}
.grid.two{grid-template-columns:repeat(2,1fr)}
@media(max-width:900px){.grid,.grid.two{grid-template-columns:repeat(2,1fr)}}
@media(max-width:600px){.grid,.grid.two{grid-template-columns:1fr}}
.card{position:relative;display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:19px;overflow:hidden;transition:transform .2s,border-color .2s,background .2s}
.card:hover{transform:translateY(-3px);border-color:var(--line2);background:var(--surface2)}
.card::before{content:"";position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--card-cat,var(--accent))}
.card .cat{display:inline-block;width:max-content;padding:3px 10px;border-radius:6px;font-size:.76rem;margin-bottom:10px}
.card h3{font-size:1.04rem;font-weight:600;line-height:1.5;margin-bottom:8px;color:#F1F5FB}
.card p{color:var(--muted);font-size:.88rem}
.card .foot{margin-top:14px;color:var(--faint);font-size:.79rem;display:flex;justify-content:space-between;align-items:center}
.card .foot .go{color:var(--accent)}
.cat-model{background:rgba(34,211,238,.15);color:#67E8F9}
.cat-product{background:rgba(96,165,250,.15);color:#93C5FD}
.cat-finance{background:rgba(251,191,36,.15);color:#FCD34D}
.cat-industry{background:rgba(52,211,153,.15);color:#6EE7B7}
.cat-research{background:rgba(244,114,182,.15);color:#F9A8D4}

/* ===== 正文页 ===== */
.article{max-width:820px}
.article h2{font-size:1.4rem;font-weight:700;margin:38px 0 12px;padding-left:11px;border-left:4px solid var(--accent)}
.article h3{font-size:1.08rem;font-weight:600;margin:24px 0 8px;color:#F1F5FB}
.article p{margin:0 0 14px}
.article ul,.article ol{margin:0 0 16px 22px}
.article li{margin-bottom:7px}
.article strong{color:#fff}
.article .lead{color:var(--muted);font-size:1.02rem;margin-bottom:26px}
.toc{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:16px 20px;margin:0 0 30px}
.toc b{display:block;font-size:.9rem;margin-bottom:8px;color:var(--accent)}
.toc ol{margin-left:18px;font-size:.9rem}
.toc a{color:var(--muted)}
.toc a:hover{color:var(--accent)}
table{border-collapse:collapse;width:100%;margin:14px 0 20px;font-size:.9rem}
th,td{border:1px solid var(--line);padding:9px 11px;text-align:left}
th{background:var(--surface);color:#fff}
.note{background:var(--surface);border-left:4px solid var(--amber);border-radius:0 var(--radius) var(--radius) 0;padding:13px 17px;margin:18px 0;color:var(--muted);font-size:.9rem}
.note b{color:var(--amber)}
.breadcrumb{font-size:.84rem;color:var(--faint);margin-bottom:14px}
.breadcrumb a{color:var(--muted)}
.breadcrumb a:hover{color:var(--accent)}

/* ===== 纯 CSS 条形图（替代 ECharts，零外部依赖） ===== */
.bars{border:1px solid var(--line);border-radius:var(--radius);padding:22px 20px;background:var(--bg2);margin:18px 0}
.bars h4{font-size:1rem;font-weight:600;margin-bottom:3px}
.bars .cap{color:var(--muted);font-size:.82rem;margin-bottom:18px}
.bar-row{display:grid;grid-template-columns:140px 1fr 90px;gap:12px;align-items:center;margin-bottom:12px;font-size:.86rem}
.bar-row .lb{color:var(--muted);text-align:right}
.bar-track{background:rgba(148,163,184,.12);border-radius:6px;height:22px;overflow:hidden}
.bar-fill{height:100%;border-radius:6px;background:linear-gradient(90deg,var(--accent),var(--blue));display:flex;align-items:center;justify-content:flex-end;padding-right:8px;color:#051022;font-size:.76rem;font-weight:600}
.bar-row .vl{color:var(--text);font-variant-numeric:tabular-nums}
@media(max-width:600px){.bar-row{grid-template-columns:96px 1fr 68px;font-size:.8rem}}

/* ===== 页脚 ===== */
footer{border-top:1px solid var(--line);margin-top:56px;padding:30px 0 46px;color:var(--faint);font-size:.84rem}
footer a{color:var(--muted)}
footer a:hover{color:var(--accent)}
.foot-in{display:flex;flex-wrap:wrap;gap:18px;justify-content:space-between}
.foot-links{display:flex;flex-wrap:wrap;gap:14px}