*{box-sizing:border-box}
:root{
  --bg:#10131a;
  --bg-deep:#090b10;
  --panel:#171c25;
  --panel2:#202838;
  --line:rgba(255,255,255,.09);
  --text:#f4f6fa;
  --muted:#aeb7c5;
  --title:#ffffff;
  --mint:#77f2d5;
  --blue:#70b7ff;
  --violet:#9d8cff;
  --accent:#ffc96b;
  --shadow:0 22px 55px rgba(0,0,0,.32);
}
html{scroll-behavior:smooth}
body{margin:0;background:radial-gradient(circle at top right,#182235 0,#10131a 38%,#0d1016 100%);color:var(--text);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;line-height:1.78;overflow-x:hidden}
body.drawer-open{overflow:hidden}
a{color:var(--mint);text-decoration:none}
img{max-width:100%}
button{font:inherit}
.site-head{position:sticky;top:0;z-index:10000;background:rgba(10,13,18,.92);backdrop-filter:blur(16px);border-bottom:1px solid var(--line)}
.head-row{max-width:1180px;min-height:70px;margin:auto;padding:0 18px;display:grid;grid-template-columns:auto 1fr auto;gap:24px;align-items:center}
.brand{display:flex;align-items:center;min-width:150px}
.brand img{height:40px;width:auto;max-width:160px;object-fit:contain}
.brand strong{font-size:20px;color:#fff}
.main-nav{display:flex;justify-content:center;gap:4px}
.main-nav a{padding:9px 13px;border-radius:10px;color:#e5ebf4;font-weight:700;white-space:nowrap}
.main-nav a.active,.main-nav a:hover{background:#1d2634;color:var(--mint)}
.primary-btn{display:inline-flex;align-items:center;justify-content:center;height:42px;min-width:100px;padding:0 18px;border-radius:10px;background:linear-gradient(135deg,var(--mint),var(--blue));color:#08110f;font-weight:900}
.subnav{background:#0d1118;border-top:1px solid rgba(255,255,255,.04)}
.subnav-inner{max-width:1180px;margin:auto;padding:8px 18px;display:flex;gap:8px;overflow-x:auto;scrollbar-width:none}
.subnav-inner::-webkit-scrollbar{display:none}
.subnav a{white-space:nowrap;color:#9da9ba;font-size:14px;padding:4px 8px}
.subnav a:hover{color:var(--mint)}
.drawer-btn{display:none;width:42px;height:42px;border:1px solid var(--line);border-radius:10px;background:#171c25;padding:10px}
.drawer-btn span{display:block;height:2px;background:#fff;margin:4px 0}
.drawer,.drawer-shade{display:none}
.site-main{min-height:60vh}
.wrap{max-width:1180px;margin:auto;padding:0 18px}
.narrow{max-width:820px;margin:auto}
.section{padding:56px 0}
.section-sm{padding:32px 0}
.eyebrow{display:inline-block;margin-bottom:10px;color:var(--accent);font-size:12px;font-weight:900;letter-spacing:.14em}
h1,h2,h3{color:var(--title);line-height:1.24;margin-top:0}
h1{font-size:clamp(32px,4.4vw,50px);letter-spacing:-.025em;margin-bottom:18px}
h2{font-size:clamp(22px,3vw,30px);margin-bottom:13px}
h3{font-size:18px}
p{margin:0 0 16px}
.lead{font-size:18px;color:#dbe1ea;max-width:760px}
.muted{color:var(--muted)}
.breadcrumb{max-width:1180px;margin:auto;padding:22px 18px 0;color:#8490a1;font-size:14px}
.breadcrumb a{color:#bdc7d4}
.hero{padding:46px 0 24px}
.hero-layout{display:grid;grid-template-columns:minmax(0,1fr) minmax(380px,.95fr);gap:28px;align-items:center}
.hero-card{padding:10px 0}
.hero-links{display:flex;flex-wrap:wrap;gap:10px;margin-top:24px}
.link-btn{display:inline-flex;align-items:center;height:42px;padding:0 14px;border-radius:10px;border:1px solid var(--line);background:#171c25;color:#eef2f8;font-weight:800}
.link-btn.accent{background:#1d2c2a;color:var(--mint);border-color:rgba(119,242,213,.22)}
.media{position:relative;width:100%;overflow:hidden;border-radius:18px;background:#151b24;border:1px solid var(--line);box-shadow:var(--shadow);aspect-ratio:16/9}
.media img{position:absolute;inset:0;width:100%;height:100%;display:block;object-fit:contain;object-position:center}
.media-empty{width:100%;height:100%;background:linear-gradient(135deg,#171d27,#202a3a)}
.media.hero-media{height:310px;aspect-ratio:auto}
.media.medium{height:230px;aspect-ratio:auto}
.media.small{height:185px;aspect-ratio:auto}
.panel{background:linear-gradient(180deg,#1b212c,#151a23);border:1px solid var(--line);border-radius:17px;padding:23px;box-shadow:0 14px 36px rgba(0,0,0,.18)}
.panel.soft{background:#202838}
.grid{display:grid;gap:18px}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}
.split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:26px;align-items:center}
.intro-strip{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0;border:1px solid var(--line);border-radius:16px;overflow:hidden;background:#151a23}
.intro-strip article{padding:20px;border-right:1px solid var(--line)}
.intro-strip article:last-child{border-right:0}
.intro-strip b{display:block;color:var(--accent);font-size:13px;margin-bottom:6px}
.intro-strip h3{margin-bottom:6px}
.intro-strip p{margin:0;color:var(--muted);font-size:14px}
.feature-board{display:grid;grid-template-columns:1.15fr .85fr;gap:20px}
.feature-main{min-height:390px;display:flex;flex-direction:column;justify-content:space-between}
.feature-side{display:grid;gap:16px}
.topic-cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.topic-card{min-height:190px;display:flex;flex-direction:column;justify-content:space-between}
.topic-card a{font-weight:900}
.reader-path{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.reader-step{padding:20px;border-top:2px solid var(--mint);background:#141922}
.reader-step span{display:inline-grid;place-items:center;width:28px;height:28px;border-radius:8px;background:#222c39;color:var(--mint);font-weight:900;margin-bottom:10px}
.reader-step p{color:var(--muted);margin:0}
.prose{max-width:820px;margin:auto;font-size:17px}
.prose h2{margin-top:34px}
.prose ul,.prose ol{padding-left:22px}
.prose li{margin-bottom:8px}
.prose .panel{margin:24px 0}
.related{display:flex;flex-wrap:wrap;gap:9px;margin-top:26px}
.related a{display:inline-flex;padding:8px 11px;border-radius:9px;background:#171c25;border:1px solid var(--line);font-weight:800}
.list-links{display:grid;gap:0}
.list-links a{display:grid;grid-template-columns:1fr auto;gap:16px;padding:16px 0;border-bottom:1px solid var(--line);color:#eff3f8}
.list-links a span:last-child{color:var(--mint);font-weight:900}
.compare{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.timeline{display:grid;gap:0}
.timeline article{display:grid;grid-template-columns:100px 1fr;gap:16px;padding:18px 0;border-bottom:1px solid var(--line)}
.timeline strong{color:var(--accent)}
.notice{padding:16px 18px;border:1px solid rgba(119,242,213,.2);border-radius:12px;background:rgba(119,242,213,.06);color:#d7eee8}
.faq{display:grid;gap:14px}
.faq article{padding:22px;border-radius:16px;background:#171c25;border:1px solid var(--line)}
.faq h2{font-size:20px}
.site-footer{margin-top:44px;background:#080a0f;border-top:1px solid var(--line)}
.footer-grid{max-width:1180px;margin:auto;padding:44px 18px 26px;display:grid;grid-template-columns:1.3fr 1fr 1fr 1fr;gap:26px}
.footer-grid>div{display:grid;align-content:start;gap:8px}
.footer-grid h2{font-size:16px;margin-bottom:4px}
.footer-grid a{color:#aab5c5;font-size:14px}
.footer-brand img{height:40px;width:auto;max-width:160px;object-fit:contain}
.footer-brand p{color:#7f8a9a;font-size:14px;max-width:270px}
.footer-note{max-width:1180px;margin:auto;padding:18px;border-top:1px solid rgba(255,255,255,.06);display:flex;justify-content:space-between;gap:20px;color:#747f90;font-size:13px}
.mobile-bar{display:none}
@media(max-width:980px){
  .head-row{grid-template-columns:42px 1fr auto;gap:12px}
  .drawer-btn{display:block}
  .brand{justify-content:center;min-width:0}
  .brand img{height:36px;max-width:145px}
  .main-nav,.subnav{display:none}
  .drawer{display:block;position:fixed;left:0;top:0;bottom:0;width:min(86vw,330px);z-index:13000;background:#10151d;border-right:1px solid var(--line);transform:translateX(-105%);transition:transform .22s ease;overflow-y:auto}
  .drawer.open{transform:translateX(0)}
  .drawer-shade{display:none;position:fixed;inset:0;z-index:12000;background:rgba(0,0,0,.58);opacity:0;pointer-events:none}
  .drawer-shade.show{display:block;opacity:1;pointer-events:auto}
  .drawer-top{display:flex;align-items:center;justify-content:space-between;padding:17px;border-bottom:1px solid var(--line);font-weight:900}
  .drawer-close{width:38px;height:38px;border-radius:9px;border:1px solid var(--line);background:#171c25;color:#fff;font-size:24px}
  .drawer section{padding:15px 18px;border-bottom:1px solid rgba(255,255,255,.06)}
  .drawer section h2{font-size:13px;color:var(--accent);margin:0 0 8px}
  .drawer section a{display:block;color:#eef2f8;padding:7px 0}
  .hero-layout,.split,.feature-board{grid-template-columns:1fr}
  .hero-media{order:-1}
  .intro-strip{grid-template-columns:1fr 1fr}
  .intro-strip article:nth-child(2){border-right:0}
  .intro-strip article{border-bottom:1px solid var(--line)}
  .topic-cards{grid-template-columns:1fr 1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:720px){
  body{padding-bottom:62px}
  .head-row{min-height:64px;padding:0 12px}
  .brand img{height:33px;max-width:126px}
  .primary-btn{height:39px;min-width:82px;padding:0 10px;font-size:14px}
  .section{padding:40px 0}
  .section-sm{padding:25px 0}
  .wrap,.breadcrumb{padding-left:14px;padding-right:14px}
  .hero{padding:24px 0 18px}
  .hero-layout{grid-template-columns:1fr}
  .media.hero-media{height:180px}
  .media.medium{height:210px}
  .grid-2,.grid-3,.grid-4,.compare,.topic-cards,.reader-path,.intro-strip{grid-template-columns:1fr}
  .intro-strip article{border-right:0}
  .prose{font-size:16px}
  .timeline article{grid-template-columns:1fr;gap:4px}
  .footer-grid{grid-template-columns:1fr}
  .footer-note{display:block}
  .mobile-bar{display:grid;position:fixed;z-index:11000;left:0;right:0;bottom:0;grid-template-columns:repeat(4,1fr);background:#080a0f;border-top:1px solid var(--line);padding-bottom:env(safe-area-inset-bottom)}
  .mobile-bar a{text-align:center;padding:11px 4px;color:#e6ebf3;font-size:14px}
}
@media(max-width:430px){
  .primary-btn{min-width:78px}
}