/* UED体育官网 — 体育装备研发AI / 工程平台样式表 */
:root{
  --paper:#f5f4ef;
  --ink:#12202c;
  --blue:#1c3f5e;
  --blue-deep:#0d2333;
  --graphite:#4a5158;
  --silver:#8b939a;
  --silver-light:#eceef0;
  --orange:#b9631f;
  --sim:#2c6e86;
  --structure:#5f4a80;
  --border:#dcd9d1;
  --panel:#ffffff;
  --muted:#5c646b;
  --maxw:1240px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:"PingFang SC","Microsoft YaHei","Segoe UI",Arial,sans-serif;
  background:
    linear-gradient(rgba(28,63,94,0.035) 1px,transparent 1px),
    linear-gradient(90deg,rgba(28,63,94,0.035) 1px,transparent 1px),
    var(--paper);
  background-size:26px 26px,26px 26px,auto;
  color:var(--ink);line-height:1.75;font-size:15px;overflow-x:hidden;
}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block;height:auto}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}
main{overflow-x:hidden}
code,.mono{font-family:Consolas,"SFMono-Regular","Courier New",monospace}

/* header */
header.site-header{background:var(--blue-deep);color:#fff;position:sticky;top:0;z-index:50;border-bottom:3px solid var(--orange)}
.top-bar{display:flex;justify-content:space-between;align-items:center;max-width:var(--maxw);margin:0 auto;padding:12px 20px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;font-size:20px;font-weight:700}
.brand img{width:34px;height:34px}
.brand small{display:block;font-size:11px;font-weight:400;color:#a9bccb;letter-spacing:.02em}
.menu-toggle{display:none;background:none;border:1px solid #33556f;color:#fff;font-size:20px;padding:4px 10px;border-radius:4px;cursor:pointer}
nav.main-nav{background:var(--blue)}
nav.main-nav ul{list-style:none;display:flex;flex-wrap:wrap;gap:2px;margin:0;padding:0 20px;max-width:var(--maxw);margin:0 auto}
nav.main-nav a{display:block;color:#eaf0f4;padding:12px 14px;font-size:14px;white-space:nowrap}
nav.main-nav a:hover,nav.main-nav a.active{background:var(--blue-deep);text-decoration:none;color:#fff}
@media(max-width:920px){
  .menu-toggle{display:inline-block}
  nav.main-nav{display:none}
  nav.main-nav.open{display:block}
  nav.main-nav ul{flex-direction:column;padding:8px 12px}
}

.crumb{font-size:13px;color:var(--muted);padding:14px 0 0}
.crumb a{color:var(--muted)}

h1{font-size:27px;line-height:1.4;margin:10px 0 14px;color:var(--blue-deep)}
h2{font-size:21px;margin:38px 0 12px;color:var(--blue-deep);position:relative;padding-left:14px}
h2::before{content:"";position:absolute;left:0;top:3px;bottom:3px;width:4px;background:var(--orange)}
h3{font-size:17px;margin:22px 0 8px;color:var(--ink)}
p{margin:0 0 14px}
.brief{font-size:16px;color:#2a3238;background:var(--panel);border:1px solid var(--border);border-left:3px solid var(--blue);border-radius:4px;padding:18px 20px}
.note{font-size:13px;color:var(--muted);background:#f0efe9;border:1px dashed var(--border);border-radius:4px;padding:10px 14px;margin:14px 0}

.grid{display:grid;gap:18px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
@media(max-width:900px){.grid-3,.grid-2{grid-template-columns:1fr}}

.panel{background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:16px 18px;position:relative}
.panel::before,.panel::after{content:"";position:absolute;width:10px;height:10px;border:1.5px solid var(--silver)}
.panel::before{top:4px;left:4px;border-right:none;border-bottom:none}
.panel::after{bottom:4px;right:4px;border-left:none;border-top:none}
.panel h3{margin-top:0}
.panel img{border-radius:2px;margin-bottom:10px;background:var(--silver-light)}
.chip{display:inline-block;background:var(--silver-light);color:var(--blue-deep);font-size:12px;padding:2px 10px;border-radius:2px;margin-bottom:8px;border:1px solid var(--border)}
.chip.sim{background:#e6eef1;color:var(--sim)}
.chip.structure{background:#ece7f1;color:var(--structure)}
.chip.material{background:#f3ede4;color:var(--orange)}

.post-list{display:flex;flex-direction:column;gap:16px}
.post{background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:16px 18px;display:grid;grid-template-columns:150px 1fr;gap:16px}
@media(max-width:700px){.post{grid-template-columns:1fr}}
.post img{border-radius:2px}
.post .meta{font-size:12px;color:var(--muted);margin-bottom:4px;font-family:Consolas,monospace}
.post .title{font-size:17px;font-weight:700;color:var(--blue-deep)}
.post .excerpt{color:#3a4145;font-size:14px;margin:8px 0 6px}
.post .preview{color:var(--muted);font-size:13.5px;border-top:1px dashed var(--border);padding-top:8px;margin-top:6px}

.pipeline{display:flex;overflow-x:auto;gap:0;margin:18px 0;padding-bottom:8px}
.pipeline .step{flex:0 0 auto;min-width:150px;padding:14px;border-top:3px solid var(--blue);position:relative;background:var(--panel);border-radius:0 0 4px 4px;margin-right:2px}
.pipeline .step .tag{font-weight:700;color:var(--blue-deep);font-size:13px;font-family:Consolas,monospace}
.pipeline .step p{font-size:13px;color:var(--muted);margin:6px 0 0}

table{width:100%;border-collapse:collapse;margin:14px 0}
th,td{border:1px solid var(--border);padding:9px 11px;text-align:left;font-size:14px;vertical-align:top}
th{background:var(--silver-light);color:var(--blue-deep)}

.stack{display:flex;flex-direction:column;gap:6px;margin:16px 0}
.stack div{background:var(--panel);border:1px solid var(--border);border-left:5px solid var(--structure);border-radius:2px;padding:10px 14px;font-size:14px}

.pillbar{display:flex;flex-wrap:wrap;gap:8px;margin:16px 0}
.pillbar a{background:var(--panel);border:1px solid var(--border);padding:6px 14px;border-radius:14px;font-size:13px}

.cta-row{display:flex;gap:12px;flex-wrap:wrap;margin:18px 0}
.btn{display:inline-block;background:var(--orange);color:#fff;padding:10px 20px;border-radius:3px;font-weight:600;border:none;cursor:pointer;font-size:14px}
.btn:hover{background:#984f18;text-decoration:none}
.btn.outline{background:#fff;color:var(--blue);border:1px solid var(--blue)}
.btn.sim{background:var(--sim)}

.seealso{background:var(--silver-light);border-radius:4px;padding:18px 20px;margin-top:32px;border-left:3px solid var(--structure)}
.seealso h3{margin-top:0;color:var(--blue-deep)}
.seealso ul{margin:0;padding-left:20px}

.faq details{background:var(--panel);border:1px solid var(--border);border-radius:3px;padding:10px 16px;margin-bottom:10px}
.faq summary{cursor:pointer;font-weight:600;color:var(--blue-deep)}
.faq[data-open="true"] summary{color:var(--orange)}

.paper{background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:22px 24px;margin:22px 0}
.paper .p-meta{font-size:12.5px;color:var(--muted);margin-bottom:6px;font-family:Consolas,monospace}
.paper h3.p-title{font-size:20px;color:var(--blue-deep);margin:0 0 10px}
.paper h4{font-size:15.5px;color:var(--blue-deep);margin:20px 0 6px}
.paper .p-figure{margin:14px 0}
.paper .p-summary{background:var(--silver-light);border-radius:3px;padding:12px 14px;font-size:13.5px;color:var(--blue-deep);margin-top:16px;border-left:3px solid var(--orange)}
.p-checked{font-size:12px;color:var(--muted);border-top:1px dashed var(--border);margin-top:16px;padding-top:10px}

.brief-note{background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:18px 20px;margin:16px 0;border-left:3px solid var(--sim)}
.brief-note .p-meta{font-size:12.5px;color:var(--muted);margin-bottom:6px;font-family:Consolas,monospace}
.brief-note h3{margin:0 0 10px;color:var(--blue-deep);font-size:18px}

.spec-tree{font-family:Consolas,"Courier New",monospace;background:var(--blue-deep);color:#d9e6ee;border-radius:4px;padding:16px 18px;font-size:13px;overflow-x:auto;white-space:pre}

.layer-tabs{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0}
.layer-tab{background:var(--panel);border:1px solid var(--border);padding:8px 14px;border-radius:3px;cursor:pointer;font-size:13.5px}
.layer-tab.active{background:var(--structure);color:#fff;border-color:var(--structure)}
.layer-panel{display:none;background:var(--panel);border:1px solid var(--border);border-radius:3px;padding:14px 16px}
.layer-panel.active{display:block}
.layer-panel table{margin:0}

.disclaimer{font-size:12.5px;color:var(--muted);background:#f0efe9;border:1px solid var(--border);border-radius:4px;padding:12px 16px;margin:24px 0}

.co-box{display:grid;grid-template-columns:1.3fr 1fr;gap:20px;align-items:start}
@media(max-width:800px){.co-box{grid-template-columns:1fr}}
.co-facts{background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:16px 18px;font-size:14px}
.co-facts dt{color:var(--muted);font-size:12.5px;margin-top:8px}
.co-facts dd{margin:2px 0 0;font-weight:600;color:var(--blue-deep)}

footer.site-footer{background:var(--blue-deep);color:#c3d1db;padding:36px 0 22px;margin-top:44px;font-size:13px}
footer.site-footer a{color:#c3d1db}
footer .foot-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:20px;margin-bottom:22px}
@media(max-width:900px){footer .foot-grid{grid-template-columns:repeat(2,1fr)}}
footer h4{color:#fff;font-size:14px;margin:0 0 10px}
footer ul{list-style:none;margin:0;padding:0}
footer li{margin-bottom:6px}
.copyright{border-top:1px solid #1c3a4d;padding-top:16px;color:#8ea1ac;font-size:12px}
.copyright p{margin:0 0 6px}

#backToTop{position:fixed;right:20px;bottom:24px;background:var(--blue);color:#fff;border:none;border-radius:3px;width:42px;height:42px;font-size:18px;cursor:pointer;display:none;box-shadow:0 2px 8px rgba(0,0,0,.25);z-index:60}
#backToTop.show{display:block}