:root{
  color-scheme:dark;
  --bg:#0b1020;
  --bg-glow:#17334a;
  --panel:#121b2e;
  --panel-2:#10182a;
  --panel-3:#101b2d;
  --form-bg:#111b2d;
  --input-bg:#0b1322;
  --ink:#f4f7fb;
  --muted:#a8b5c8;
  --muted-2:#8494aa;
  --line:#26334a;
  --line-2:#30435a;
  --line-3:#35465d;
  --accent:#8ee3c0;
  --accent-ink:#10251f;
  --accent-text:#8ee3c0;
  --target-bg:#142d2b;
  --target-line:#5b9d88;
  --notice-bg:#15382e;
  --notice-ink:#c7f7e3;
  --error-bg:#3a1e26;
  --error-ink:#ffd7df;
  --visual-a:#17263b;
  --visual-b:#0f1728;
  --shadow:0 24px 70px #0004;
  --focus:#8ee3c0;
}
[data-theme="light"]{
  color-scheme:light;
  --bg:#f5f8fa;
  --bg-glow:#d9f3ea;
  --panel:#ffffff;
  --panel-2:#ffffff;
  --panel-3:#f9fbfd;
  --form-bg:#ffffff;
  --input-bg:#ffffff;
  --ink:#0b1424;
  --muted:#4d5f76;
  --muted-2:#5f7088;
  --line:#dbe4ee;
  --line-2:#c9d5e2;
  --line-3:#c2cfdd;
  --accent:#0a7f5c;
  --accent-ink:#ffffff;
  --accent-text:#087153;
  --target-bg:#e8f8f1;
  --target-line:#0a7f5c;
  --notice-bg:#e6f7ef;
  --notice-ink:#085c43;
  --error-bg:#fdecef;
  --error-ink:#8a1c2c;
  --visual-a:#eef8f4;
  --visual-b:#ffffff;
  --shadow:0 20px 50px rgba(15,40,60,.10);
  --focus:#0a7f5c;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scrollbar-gutter:stable}
@media (prefers-reduced-motion: reduce){html{scroll-behavior:auto}}
body{
  margin:0;
  background:radial-gradient(ellipse at 75% 0%,var(--bg-glow) 0,transparent 38%),var(--bg);
  color:var(--ink);
  font:16px/1.6 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
}
.wrap{width:min(1120px,calc(100% - 40px));margin:auto}
header{padding:24px 0;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:21px;letter-spacing:-.03em;color:var(--ink);text-decoration:none}
.mark{width:32px;height:32px;display:block;flex:none}
.brand-flow{color:var(--accent-text)}
.header-tools{display:flex;align-items:center;gap:10px;margin-left:auto}
.navlink{font-size:14px;text-decoration:none;color:var(--muted);white-space:nowrap}
.navlink:hover{color:var(--ink)}
/* Fixed widths keep the right-hand group from shifting when the language changes. */
.articles-link{display:inline-block;width:4.9em;text-align:center}
.cta-link{display:inline-block;width:12em;text-align:right}
.icon-btn{width:38px;height:38px;display:grid;place-items:center;border-radius:11px;border:1px solid var(--line);background:var(--panel);color:var(--ink);cursor:pointer;padding:0}
.icon-btn:hover{border-color:var(--accent-text);color:var(--accent-text)}
.icon-btn svg{width:17px;height:17px;display:block}
.icon-btn .icon-sun{display:block}
.icon-btn .icon-moon{display:none}
[data-theme="light"] .icon-btn .icon-sun{display:none}
[data-theme="light"] .icon-btn .icon-moon{display:block}
.seg{display:inline-flex;border:1px solid var(--line);background:var(--panel);border-radius:11px;padding:3px;gap:2px}
.seg a,.seg button{border:0;background:transparent;color:var(--muted);font:inherit;font-size:13px;font-weight:700;padding:6px 9px;border-radius:8px;cursor:pointer;line-height:1;text-decoration:none}
.seg a{width:38px;padding:6px 0;text-align:center}
.seg a[aria-current="page"],.seg button[aria-pressed="true"]{background:var(--accent);color:var(--accent-ink)}
.seg a:hover:not([aria-current="page"]),.seg button:hover:not([aria-pressed="true"]){color:var(--ink)}
:where(a,button,input,select,textarea,summary):focus-visible{outline:2px solid var(--focus);outline-offset:2px}
.hero{padding:72px 0 64px;display:grid;grid-template-columns:1.1fr .9fr;gap:54px;align-items:center}
.eyebrow{color:var(--accent-text);text-transform:uppercase;letter-spacing:.14em;font-size:12px;font-weight:800}
[lang="zh-Hans"] .eyebrow{letter-spacing:.06em}
h1{font-size:clamp(42px,6vw,68px);line-height:1.03;letter-spacing:-.055em;margin:18px 0}
h2{font-size:clamp(28px,4vw,40px);line-height:1.15;letter-spacing:-.04em;margin:0 0 14px}
p{color:var(--muted);margin:0 0 18px}
.hero p{font-size:18px;max-width:580px}
.actions{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-top:26px}
.btn{display:inline-flex;justify-content:center;align-items:center;padding:13px 18px;border-radius:11px;background:var(--accent);color:var(--accent-ink);text-decoration:none;font-weight:800;border:0;cursor:pointer;font:inherit}
.btn:hover{filter:brightness(1.04)}
.btn:disabled{background:var(--line);color:var(--muted);opacity:1;cursor:not-allowed;filter:none}
.btn.secondary{background:transparent;color:var(--ink);border:1px solid var(--line)}
.btn.secondary:hover{border-color:var(--accent-text);color:var(--accent-text);filter:none}
.fine{font-size:12px;color:var(--muted-2);margin-top:12px}
.visual{border:1px solid var(--line-2);border-radius:24px;padding:24px;background:linear-gradient(150deg,var(--visual-a),var(--visual-b));box-shadow:var(--shadow)}
.visual-head{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-bottom:20px;font-size:13px;color:var(--muted)}
.live{color:var(--accent-text);font-size:12px}
.node{padding:15px 16px;border:1px solid var(--line-2);border-radius:14px;background:var(--panel-3);margin:10px 0}
.node strong{display:block;font-size:14px}
.node small{color:var(--muted)}
.arrow{text-align:center;color:var(--accent-text);font-size:24px;line-height:1.2}
.node.target{border-color:var(--target-line);background:var(--target-bg)}
section{padding:64px 0;border-top:1px solid var(--line)}
.section-intro{max-width:680px;margin-bottom:30px}
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.card{padding:23px;border:1px solid var(--line);background:var(--panel-2);border-radius:16px}
.num{color:var(--accent-text);font-size:13px;font-weight:800}
.card h3{margin:10px 0 8px;font-size:18px}
.card p{font-size:14px;margin:0}
.two{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:start}
.checks{list-style:none;padding:0;margin:22px 0}
.checks li{padding:10px 0;border-bottom:1px solid var(--line);color:var(--ink)}
.checks li:before{content:"✓";color:var(--accent-text);font-weight:900;margin-right:12px}
.formbox{background:var(--form-bg);border:1px solid var(--line-2);border-radius:20px;padding:26px}
label,.asset-title{display:block;font-size:13px;color:var(--ink);font-weight:650;margin:15px 0 7px}
input,select,textarea{width:100%;padding:12px 13px;border-radius:10px;border:1px solid var(--line-3);background:var(--input-bg);color:var(--ink);font:inherit}
input::placeholder,textarea::placeholder{color:var(--muted-2)}
textarea{min-height:88px;resize:vertical}
.formrow{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.assets{display:grid;grid-template-columns:1fr 1fr;gap:8px 14px;margin:14px 0 4px}
.asset{display:flex;gap:9px;align-items:flex-start;font-size:13px;font-weight:400;color:var(--muted);margin:0}
.asset input{width:auto;margin:4px 0 0}
.consent{display:flex;gap:9px;align-items:flex-start;font-size:12px;color:var(--muted);margin:16px 0}
.consent input{width:auto;margin-top:4px}
.notice{padding:14px;border-radius:10px;background:var(--notice-bg);color:var(--notice-ink);margin-top:15px;font-size:14px}
.notice[hidden]{display:none}
.notice.err{background:var(--error-bg);color:var(--error-ink)}
.honeypot{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}
.turnstile{margin-top:15px}
.formbox button[type="submit"]{width:100%}
.faq{max-width:780px}
.faq details{padding:18px 0;border-bottom:1px solid var(--line)}
.faq summary{cursor:pointer;font-weight:750;color:var(--ink)}
.faq details p{margin:12px 0 0}
#privacy .priv{max-width:780px}
#privacy h3{font-size:16px;margin:26px 0 6px;color:var(--ink)}
#privacy p,#privacy li{font-size:14px;color:var(--muted)}
#privacy ul{padding-left:20px;margin:0 0 14px}
#privacy a{color:var(--accent-text)}
footer a{color:inherit}
footer{padding:28px 0 44px;border-top:1px solid var(--line);color:var(--muted-2);font-size:12px;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap}
.articles-hero{padding:64px 0 22px}
.articles-hero h1{font-size:clamp(38px,5.4vw,58px);max-width:860px;margin:14px 0 16px}
.articles-hero p{font-size:18px;max-width:700px;margin:0}
.article-list{display:grid;gap:16px;padding:18px 0 72px}
.article-card{display:block;padding:26px;border:1px solid var(--line);border-radius:18px;background:var(--panel-2);color:var(--ink);text-decoration:none}
.article-card:hover{border-color:var(--accent-text)}
.article-card h2,.article-card h3{margin:9px 0 10px;font-size:clamp(23px,3vw,30px);line-height:1.18;letter-spacing:-.03em}
.article-card p{font-size:15px;max-width:760px;margin:0 0 16px}
.article-meta{display:flex;align-items:center;gap:8px;flex-wrap:wrap;color:var(--muted-2);font-size:12px;letter-spacing:.02em}
.dot{color:var(--line-3)}
.read-more{font-size:14px;font-weight:800;color:var(--accent-text)}
#articles .article-card{max-width:820px}
.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:64px;align-items:start;padding:58px 0 10px}
.article{max-width:820px;padding:0}
.article-rail{position:sticky;top:28px;align-self:start;padding-top:64px}
.rail-card{border:1px solid var(--line);border-radius:16px;background:var(--panel-2);padding:18px}
.rail-card .eyebrow{font-size:11px;margin-bottom:10px}
.toc{display:grid;gap:2px}
.toc a{color:var(--muted);text-decoration:none;font-size:14px;line-height:1.45;padding:7px 10px;border-left:2px solid transparent;border-radius:0 6px 6px 0}
.toc a:hover{color:var(--ink);background:var(--panel-3);border-left-color:var(--accent-text)}
.article h1{font-size:clamp(36px,5.2vw,58px);line-height:1.05;margin:16px 0 18px;letter-spacing:-.045em}
.lede{font-size:19px;line-height:1.55;color:var(--ink);max-width:740px;margin-bottom:20px}
.article .article-meta{padding:0 0 24px;border-bottom:1px solid var(--line);margin-bottom:8px}
.prose{max-width:740px;padding-top:10px}
.prose p,.prose li{font-size:17px;line-height:1.75;color:var(--muted)}
.prose p{margin:0 0 20px}
.prose h2{font-size:clamp(23px,3vw,29px);line-height:1.2;letter-spacing:-.025em;margin:42px 0 14px;color:var(--ink);scroll-margin-top:24px}
.prose h3{font-size:19px;margin:30px 0 10px;color:var(--ink)}
.prose ul,.prose ol{padding-left:22px;margin:0 0 22px}
.prose li{margin:0 0 10px}
.prose li strong,.prose p strong{color:var(--ink)}
.prose a{color:var(--accent-text);text-decoration:underline;text-underline-offset:2px}
.prose blockquote{margin:26px 0;padding:18px 22px;border-left:3px solid var(--accent);border-radius:0 12px 12px 0;background:var(--panel-2);color:var(--ink)}
.prose blockquote p{margin:0;font-size:16px}
.callout{margin:28px 0;padding:20px 22px;border:1px solid var(--line-2);border-left:3px solid var(--accent);border-radius:0 14px 14px 0;background:var(--panel-2)}
.callout strong{display:block;color:var(--ink);font-size:13px;text-transform:uppercase;letter-spacing:.12em;margin-bottom:8px}
[lang="zh-Hans"] .callout strong{letter-spacing:.06em}
.callout p{margin:0;font-size:15px;line-height:1.7}
.article-cta{margin:48px 0 0;padding:28px;border:1px solid var(--line-2);border-radius:20px;background:linear-gradient(150deg,var(--visual-a),var(--visual-b));box-shadow:var(--shadow)}
.article-cta h2{font-size:clamp(23px,3vw,30px);margin:8px 0 10px}
.article-cta p{max-width:560px;font-size:15px}
.article-cta .btn{margin-top:6px}
.article > .fine{margin:18px 0 0}
.article-nav{padding:30px 0 60px;margin-top:34px;border-top:1px solid var(--line)}
.article-nav a{color:var(--muted);text-decoration:none;font-size:14px}
.article-nav a:hover{color:var(--ink)}
@media (prefers-reduced-motion: no-preference){
  body,.card,.article-card,.formbox,.visual,.node,input,select,textarea,.icon-btn,.seg,.btn{transition:background-color .18s ease,border-color .18s ease,color .18s ease}
}
@media(max-width:1080px){.article-layout{grid-template-columns:1fr;padding-top:40px}.article{max-width:820px;margin-inline:auto}.article-rail{display:none}}
@media(max-width:800px){.hero,.two{grid-template-columns:1fr}.hero{padding-top:42px;gap:34px}.grid{grid-template-columns:1fr}.formrow{grid-template-columns:1fr}.article-card{padding:20px}}
@media(max-width:640px){.navlink{display:none}header{padding:18px 0}.header-tools{gap:8px}.navlink.articles-link{display:inline;font-size:13px}.articles-hero{padding-top:40px}.article-list{padding-bottom:48px}.prose p,.prose li{font-size:16px}.article-cta{padding:22px}footer{justify-content:flex-start;gap:8px 16px}footer>span{flex-basis:100%}}
@media(max-width:420px){.asset{font-size:12px}}