/* ① 变量 */
:root{
  --bg:#0e0c0d;
  --fg:#e9e5e3;
  --muted:#9a9294;
  --line:#2b2427;
  --accent:#7d1b25;
  --accent-2:#b8353f;
  --gap:32px;
  --radius:6px;
  --shadow:0 10px 30px rgba(0,0,0,.6);
  --font:"Segoe UI","Microsoft YaHei",sans-serif;
}
/* ② reset 与 body */
*,*::before,*::after{box-sizing:border-box;}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;}
body{
  margin:0;
  background:var(--bg);
  color:var(--fg);
  font-family:"Segoe UI","Microsoft YaHei",sans-serif;
  font-size:17px;
  line-height:1.7;
  background-image:linear-gradient(180deg,rgba(125,27,37,.13),rgba(14,12,13,0) 400px);
}
h1,h2,h3,h4{margin:0;font-weight:600;line-height:1.28;}
p{margin:0 0 14px;}
ul,ol{margin:0 0 14px;padding-left:20px;}
li{margin-bottom:6px;}
a{color:var(--fg);text-decoration:none;transition:color .18s ease,border-color .18s ease;}
a:hover{color:var(--accent-2);}
img{max-width:100%;display:block;border-radius:4px;}
::selection{background:var(--accent);color:#fff;}
/* ③ 布局 */
.portalbeidan-shell{max-width:1280px;margin:0 auto;padding:0 20px;}
.portalbeidan-topbar{background:#141011;border-bottom:2px solid var(--accent);position:sticky;top:0;z-index:40;}
.portalbeidan-topbar-inner{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:12px 20px;flex-wrap:wrap;}
.portalbeidan-brand{font-size:21px;font-weight:700;letter-spacing:2px;color:var(--fg);}
.portalbeidan-brand span{color:var(--accent-2);font-size:14px;letter-spacing:1px;margin-left:6px;}
.portalbeidan-nav{flex:1 1 auto;display:flex;justify-content:flex-end;}
.nav-links{display:flex;flex-wrap:wrap;gap:6px 18px;align-items:center;}
.nav-links a{font-size:15px;color:#cfc8c6;padding:4px 2px;border-bottom:1px solid transparent;}
.nav-links a:hover{color:#fff;border-bottom-color:var(--accent-2);}
.nav-links a:first-child{color:var(--accent-2);font-weight:700;}
.portalbeidan-hero{padding:44px 0 30px;border-bottom:1px solid var(--line);}
.portalbeidan-hero h1{font-size:44px;line-height:1.2;max-width:860px;letter-spacing:1px;}
.portalbeidan-hero h1 em{font-style:normal;color:var(--accent-2);}
.portalbeidan-metrics{list-style:none;display:flex;flex-wrap:wrap;gap:12px 28px;margin:22px 0 24px;padding:0;}
.portalbeidan-metrics li{font-size:17px;color:var(--fg);padding:6px 16px;border:1px solid var(--line);border-radius:2px;background:#151113;position:relative;}
.portalbeidan-metrics li::before{content:"";position:absolute;left:0;top:0;bottom:0;width:2px;background:var(--accent-2);}
.portalbeidan-hero-lead{max-width:900px;}
.portalbeidan-hero-lead p{font-size:17px;color:#d6cfcd;}
.portalbeidan-layout{display:grid;grid-template-columns:minmax(0,1fr) 288px 196px;gap:var(--gap);align-items:start;padding:var(--gap) 0 48px;}
.portalbeidan-maincol{grid-column:1;grid-row:1 / span 2;display:grid;gap:var(--gap);}
.portalbeidan-sidecol{grid-column:2;grid-row:1;display:grid;gap:var(--gap);}
.portalbeidan-notecol{grid-column:3;grid-row:1;display:grid;gap:var(--gap);}
/* ④ 组件 */
.portalbeidan-block{background:#141112;border:1px solid var(--line);border-radius:var(--radius);padding:22px 24px;position:relative;box-shadow:var(--shadow);}
.portalbeidan-block::before{content:"";position:absolute;top:-1px;left:22px;right:22px;height:3px;background:linear-gradient(90deg,transparent,var(--accent-2),var(--accent),transparent);}
.portalbeidan-block::after{content:"";position:absolute;left:50%;top:-9px;width:14px;height:14px;margin-left:-7px;background:var(--accent);transform:rotate(45deg);border:1px solid var(--accent-2);}
.portalbeidan-block h2{font-size:28px;margin-bottom:14px;letter-spacing:.5px;}
.portalbeidan-block h2 span{color:var(--accent-2);}
.portalbeidan-block p{font-size:16px;color:#d2cbca;}
.portalbeidan-block ul,.portalbeidan-block ol{font-size:16px;color:#d2cbca;}
.portalbeidan-card{background:linear-gradient(160deg,#6d1620,#2a1013 72%);color:#fff;padding:18px 20px;border-radius:var(--radius);position:relative;transition:transform .2s ease,box-shadow .2s ease;border:1px solid #43141a;}
.portalbeidan-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);}
.portalbeidan-card h3{font-size:21px;color:#fff;margin-bottom:8px;letter-spacing:.5px;}
.portalbeidan-card p{color:#e6d9d8;font-size:15px;margin:0;}
.portalbeidan-card::before{content:"◈";position:absolute;right:12px;top:8px;color:#c9838a;font-size:14px;}
.portalbeidan-timeline{list-style:none;margin:0;padding:0 0 0 24px;border-left:2px solid var(--line);}
.portalbeidan-timeline li{position:relative;padding:0 0 24px 18px;margin:0;}
.portalbeidan-timeline li::before{content:"";position:absolute;left:-31px;top:9px;width:10px;height:10px;border-radius:50%;background:var(--accent-2);box-shadow:0 0 0 3px #1a1416;}
.portalbeidan-timeline li:last-child{padding-bottom:0;}
.portalbeidan-news-title{font-size:21px;margin-bottom:6px;color:#f1ebe9;}
.portalbeidan-news-date{font-size:13px;color:var(--accent-2);letter-spacing:1px;margin:0 0 6px;}
.portalbeidan-news-body{font-size:15px;color:#bdb5b4;margin:0;}
.portalbeidan-faq{display:grid;grid-template-columns:1fr 1fr;gap:14px;align-items:stretch;}
.portalbeidan-faq details{background:#171314;border:1px solid var(--line);border-radius:var(--radius);padding:12px 16px;transition:border-color .18s ease,background .18s ease;}
.portalbeidan-faq details:hover{border-color:#4a1d23;}
.portalbeidan-faq details[open]{border-color:var(--accent);background:#1a1416;}
.portalbeidan-faq summary{cursor:pointer;font-size:15px;color:#e8e2e1;list-style:none;position:relative;padding-right:18px;}
.portalbeidan-faq summary::-webkit-details-marker{display:none;}
.portalbeidan-faq summary::after{content:"+";position:absolute;right:0;top:0;color:var(--accent-2);}
.portalbeidan-faq details[open] summary::after{content:"−";}
.portalbeidan-faq p{font-size:14px;color:#b3abaa;margin:10px 0 0;line-height:1.7;}
.portalbeidan-table{width:100%;border-collapse:collapse;font-size:14px;margin-top:6px;}
.portalbeidan-table th,.portalbeidan-table td{border:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:top;}
.portalbeidan-table th{background:#1c1618;color:#dcd4d3;font-weight:600;}
.portalbeidan-table tbody tr:nth-child(even){background:#171314;}
.portalbeidan-table tbody tr:hover{background:#211a1c;}
.portalbeidan-btn{display:inline-block;padding:10px 22px;background:var(--accent);color:#fff;border-radius:var(--radius);font-size:15px;border:1px solid var(--accent-2);cursor:pointer;transition:background .2s ease,transform .12s ease;}
.portalbeidan-btn:hover{background:var(--accent-2);color:#fff;}
.portalbeidan-btn:active{transform:translateY(1px);}
.portalbeidan-btn:focus-visible{outline:2px solid #fff;outline-offset:2px;}
.portalbeidan-tag{display:inline-block;font-size:12px;letter-spacing:1px;color:#f0dedd;background:#3a1418;border:1px solid #5a2027;border-radius:2px;padding:2px 8px;margin-bottom:10px;}
.portalbeidan-notelist{list-style:none;padding:0;margin:0;}
.portalbeidan-notelist li{font-size:14px;color:#c6bebd;padding:8px 0;border-bottom:1px dashed var(--line);}
.portalbeidan-notelist li:last-child{border-bottom:0;}
.portalbeidan-figure{margin:16px 0 0;}
.portalbeidan-figure figcaption{font-size:13px;color:var(--muted);margin-top:8px;}
.portalbeidan-footer{background:#100d0e;border-top:2px solid var(--accent);padding:32px 0 20px;color:var(--muted);font-size:14px;}
.portalbeidan-footer-inner{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;}
.portalbeidan-footer p{margin:0 0 8px;font-size:14px;color:var(--muted);}
.portalbeidan-footer a{color:#cfc8c6;border-bottom:1px solid #3a3234;}
.portalbeidan-footer a:hover{color:#fff;border-bottom-color:var(--accent-2);}
.portalbeidan-footer-bottom{border-top:1px solid var(--line);margin-top:18px;padding-top:14px;font-size:13px;color:#7d7576;}
/* ⑤ 状态 */
.portalbeidan-block:nth-child(even){background:#131011;}
.portalbeidan-notelist li:hover{color:#fff;}
.portalbeidan-card:first-child{background:linear-gradient(160deg,#7d1b25,#2a1013 74%);}
.portalbeidan-newsitem{transition:opacity .2s ease;}
.portalbeidan-timeline li:hover .portalbeidan-news-title{color:var(--accent-2);}
.portalbeidan-faq details:nth-child(odd){background:#161213;}
.portalbeidan-btn:visited{color:#fff;}
.portalbeidan-metrics li:hover{border-color:var(--accent);color:#fff;}
.portalbeidan-footer-bottom a{margin:0 4px;}
/* ⑥ 响应式 */
@media (max-width:1024px){
  .portalbeidan-layout{grid-template-columns:minmax(0,1fr) 280px;}
  .portalbeidan-maincol{grid-row:auto;grid-column:1;}
  .portalbeidan-sidecol{grid-column:2;grid-row:1;}
  .portalbeidan-notecol{grid-column:1 / -1;grid-row:auto;grid-template-columns:repeat(2,minmax(0,1fr));}
  .portalbeidan-hero h1{font-size:34px;}
  .portalbeidan-faq{grid-template-columns:1fr;}
  .portalbeidan-footer-inner{grid-template-columns:repeat(2,minmax(0,1fr));}
  .nav-links{gap:6px 14px;}
}
@media (max-width:720px){
  body{font-size:16px;}
  .portalbeidan-layout{grid-template-columns:1fr;padding-bottom:32px;}
  .portalbeidan-maincol,.portalbeidan-sidecol,.portalbeidan-notecol{grid-column:1;grid-row:auto;}
  .portalbeidan-notecol{grid-template-columns:1fr;}
  .portalbeidan-hero{padding:28px 0 22px;}
  .portalbeidan-hero h1{font-size:26px;}
  .portalbeidan-block{padding:18px 16px;}
  .portalbeidan-block h2{font-size:21px;}
  .portalbeidan-topbar-inner{flex-direction:column;align-items:flex-start;gap:10px;}
  .portalbeidan-nav{justify-content:flex-start;}
  .nav-links{gap:4px 12px;}
  .nav-links a{font-size:14px;}
  .portalbeidan-footer-inner{grid-template-columns:1fr;}
  .portalbeidan-metrics li{font-size:15px;padding:5px 12px;}
  .portalbeidan-timeline{padding-left:18px;}
  .portalbeidan-timeline li{padding-left:14px;}
  .portalbeidan-timeline li::before{left:-25px;}
}