:root{
  --bg:#F4F7F6;--bg-panel:#FFFFFF;--bg-panel-2:#EAF0EF;--border:#DCE5E3;
  --accent:#12A39A;--accent-2:#3FCFC0;--accent-dark:#0B6F69;--accent-soft:#DDF3F0;--accent-mist:#EEF8F7;
  --text:#111C24;--text-muted:#5B6B72;--success:#1E9E5A;--warn:#C98A0B;--error:#D2453B;
  --ink-1:#0B3B3A;--ink-2:#12263A;--on-ink:#FFFFFF;--on-ink-muted:rgba(255,255,255,.78);--on-ink-line:rgba(255,255,255,.6);--on-ink-hover:rgba(255,255,255,.12);
  --flag-red:#DA2A35;--flag-white:#FFFFFF;--flag-navy:#1D2B6B;--flag-edge:rgba(17,28,36,.14);
  --atmo-top:rgba(18,163,154,.04);--atmo-bottom:rgba(18,163,154,.07);--halo:rgba(63,207,192,.16);--halo-2:rgba(18,163,154,.08);
  --shadow-tint:0 18px 40px rgba(18,163,154,.10);--shadow-chip:0 8px 22px rgba(18,163,154,.12);--shadow-ink:0 1px 2px rgba(17,28,36,.05);
  --hl-inset:inset 0 1px 0 rgba(255,255,255,1),inset 0 0 0 1px rgba(255,255,255,.7);
  --card-inner:inset 0 -18px 28px -22px rgba(18,163,154,.16);
  --accent-glow:rgba(18,163,154,.28);--hl-on-accent:rgba(255,255,255,.38);--knob-shadow:rgba(11,111,105,.35);--track-inset:rgba(11,111,105,.25);
  --veil:rgba(17,28,36,.25);--clear:transparent;
  --radius:8px;--radius-sm:6px;--radius-pill:999px;--radius-tiny:3px;--radius-state:4px;--radius-icon:5px;--radius-line:2px;--radius-round:50%;
  --font-display:'Inter','Noto Sans SC','Noto Sans JP','Noto Sans KR','PingFang SC','Microsoft YaHei',system-ui,sans-serif;
  --font-body:'Inter','Noto Sans SC','Noto Sans JP','Noto Sans KR','PingFang SC','Hiragino Sans','Microsoft YaHei',system-ui,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,'SFMono-Regular',Menlo,Consolas,monospace;
  --weight-normal:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-heavy:800;--weight-display:900;
  --text-xs:12px;--text-sm:13px;--text-base:15px;--text-lg:18px;--text-subtitle:20px;
  --space-unit:8px;--gutter:24px;--content-width:1248px;--reading-width:848px;--section-space:64px;
  --anchor-offset:96px;--toc-top:16px;--toc-offset:88px;--ease:ease;--time-fast:.2s;--time-enter:.6s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--text-base);line-height:1.6;-webkit-font-smoothing:antialiased}
[hidden]{display:none!important}
img,video{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
a{color:inherit;text-underline-offset:4px}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,a,summary,input,select,textarea{touch-action:manipulation}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent-dark);outline-offset:3px}
button:disabled,.btn[aria-disabled="true"]{cursor:not-allowed;opacity:.55}
p{margin:0 0 16px}
h1,h2,h3,h4{font-family:var(--font-display);text-wrap:balance;overflow-wrap:break-word}
h1{margin:0 0 24px;font-size:clamp(52px,4.2vw,72px);font-weight:var(--weight-display);line-height:1.1;letter-spacing:-.02em}
h2{margin:0 0 24px;font-size:36px;line-height:1.2;font-weight:var(--weight-display);letter-spacing:-.02em}
h3{margin:0 0 16px;font-size:24px;line-height:1.3;font-weight:var(--weight-heavy)}
h4{font-size:var(--text-lg);font-weight:var(--weight-bold)}
strong{font-weight:var(--weight-semibold)}
ul,ol{padding-left:24px}
li{margin-bottom:4px}
:where(.grid,.device-grid,.feature-row,.footer-grid,.plan-grid,.platform-grid,.article-grid)>*{min-width:0}
code{font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere}
p code,li code{background:var(--bg-panel-2);padding:2px 4px;border-radius:var(--radius-state)}
pre{max-width:100%;overflow-x:auto;padding:24px;border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-panel);color:var(--text)}
pre code{white-space:pre;overflow-wrap:normal}
.wrap{width:100%;max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose li{line-height:1.9}
.prose h2{margin-top:48px}
.prose h3{margin-top:32px}
.prose a{color:var(--accent-dark)}
.prose :first-child{margin-top:0}
.no-break{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.muted{color:var(--text-muted)}
.eyebrow{margin:0 0 8px;font-family:var(--font-mono);font-size:var(--text-xs);font-weight:var(--weight-semibold);letter-spacing:.1em;color:var(--accent)}
.panel,.card{padding:24px;border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-panel);box-shadow:var(--shadow-tint),var(--hl-inset)}
.grid{display:grid;gap:24px;grid-template-columns:repeat(2,minmax(0,1fr))}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:48px;padding:10px 22px;border:1px solid var(--clear);border-radius:var(--radius);font-size:16px;font-weight:var(--weight-bold);text-decoration:none;letter-spacing:.01em;transition:transform var(--time-fast) var(--ease),box-shadow var(--time-fast) var(--ease);flex-shrink:0;white-space:nowrap}
.btn svg{width:18px;height:18px;transition:transform var(--time-fast) var(--ease)}
.btn-primary{color:var(--bg-panel);background:linear-gradient(135deg,var(--accent-2) -30%,var(--accent) 45%,var(--accent-dark) 125%);box-shadow:0 10px 24px var(--accent-glow),inset 0 1px 0 var(--hl-on-accent)}
.btn-primary:hover{transform:translateY(-1px)}
.btn-primary:hover svg{transform:translateX(3px)}
.btn-ghost,.btn-secondary{color:var(--text);background:var(--bg-panel);border-color:var(--border);box-shadow:var(--shadow-ink),var(--hl-inset)}
.btn-ghost:hover,.btn-secondary:hover{border-color:var(--accent-2)}
.btn-small{min-height:36px;font-size:var(--text-sm);padding:6px 14px}
.cta-row{display:flex;flex-wrap:wrap;justify-content:center;gap:12px}
.notice{display:flex;align-items:center;justify-content:center;gap:16px;min-height:40px;padding:0 24px;background:linear-gradient(90deg,var(--ink-1),var(--ink-2));color:var(--on-ink);font-size:13.5px}
.notice-text{margin:0;display:flex;flex-wrap:wrap;align-items:center;gap:12px}
.notice-text strong{font-weight:var(--weight-bold);letter-spacing:.01em}
.notice-text span{color:var(--on-ink-muted)}
.notice-btn{display:inline-flex;align-items:center;justify-content:center;min-height:26px;padding:0 12px;border:1px solid var(--on-ink-line);border-radius:var(--radius-pill);font-size:12.5px;font-weight:var(--weight-semibold);text-decoration:none;color:var(--on-ink);white-space:nowrap}
.notice-btn:hover{background:var(--on-ink-hover)}
.topbar{position:relative;z-index:40;padding:12px 24px 0}
.topbar-in{position:relative;max-width:1200px;min-height:58px;margin:0 auto;display:flex;align-items:center;gap:28px;padding:0 10px 0 16px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-tint),var(--hl-inset)}
.brand{display:inline-flex;align-items:center;gap:10px;text-decoration:none;flex:none;min-height:36px}
.brand .logo{width:30px;height:30px;flex:none}
.brand-en{font-family:var(--font-display);font-weight:var(--weight-display);font-size:18px;letter-spacing:-.02em;color:var(--text)}
.brand-zh{font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--text-muted);padding-left:10px;border-left:1px solid var(--border);line-height:1}
.tabs{min-width:0}
.tabs ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px;height:56px}
.tabs li{margin:0}
.tab{position:relative;display:flex;align-items:center;justify-content:center;height:56px;padding:0 12px;font-size:14px;font-weight:var(--weight-medium);color:var(--text-muted);text-decoration:none;white-space:nowrap}
.tab::after{content:"";position:absolute;left:12px;right:12px;bottom:-1px;height:2px;border-radius:var(--radius-line);background:var(--accent);transform:scaleX(0);transition:transform .25s var(--ease)}
.tab:hover{color:var(--text)}
.tab:hover::after{transform:scaleX(.45)}
.tab[aria-current="page"]{color:var(--text);font-weight:var(--weight-semibold)}
.tab[aria-current="page"]::after{transform:scaleX(1)}
.nav-tools{margin-left:auto;display:flex;align-items:center;gap:8px;flex:none}
.lang-control{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;height:36px;padding:0 10px;border:1px solid var(--clear);border-radius:var(--radius);background:var(--clear);color:var(--text-muted);font-size:var(--text-sm)}
.lang span{white-space:nowrap}
.lang svg{width:15px;height:15px}
.lang:hover{background:var(--bg-panel-2);border-color:var(--border)}
.lang-menu{position:absolute;right:0;top:calc(100% + 8px);min-width:176px;padding:8px;border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-panel);box-shadow:var(--shadow-tint);z-index:45}
.lang-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;text-decoration:none;border-radius:var(--radius-sm)}
.lang-menu a:hover,.lang-menu a[aria-current="true"]{color:var(--accent-dark);background:var(--accent-soft)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:36px;padding:0 18px;border-radius:var(--radius);background:var(--accent-dark);color:var(--bg-panel);font-size:14px;font-weight:var(--weight-semibold);text-decoration:none;white-space:nowrap;box-shadow:inset 0 1px 0 var(--hl-on-accent)}
.login:hover{background:var(--accent)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--radius);color:var(--text);background:var(--bg-panel)}
.menu-toggle svg{width:20px;height:20px}
.mobile-drawer{position:absolute;top:calc(100% + 8px);left:0;right:0;z-index:43;max-height:calc(100dvh - 120px);overflow-y:auto;overscroll-behavior:contain;padding:12px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-tint)}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;text-decoration:none;border-radius:var(--radius-sm)}
.mobile-drawer a[aria-current="page"],.mobile-drawer a[aria-current="true"]{background:var(--accent-soft);color:var(--accent-dark)}
.mobile-drawer ul{list-style:none;margin:0;padding:0}
.mobile-drawer li{margin:0}
.drawer-languages{border-top:1px solid var(--border);padding-top:8px;margin-top:8px}
.nav-veil{position:fixed;inset:0;z-index:35;border:0;background:var(--veil)}
.site-footer{padding-top:48px;padding-bottom:32px;border-top:1px solid var(--border);background:linear-gradient(180deg,var(--bg-panel),var(--accent-mist))}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr 1fr;gap:32px}
.footer-brand p{margin-top:16px;max-width:320px;color:var(--text-muted);font-size:14px}
.footer-title{font-size:14px;font-weight:var(--weight-bold);margin:0 0 12px}
.footer-list{list-style:none;margin:0;padding:0}
.footer-list a{display:inline-flex;align-items:center;min-height:28px;padding-block:2px;font-size:var(--text-sm);color:var(--text-muted);text-decoration:none}
.footer-list a:hover{color:var(--accent-dark)}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;gap:16px;margin-top:32px;padding-top:24px;border-top:1px solid var(--border);color:var(--text-muted);font-size:var(--text-xs)}
.footer-bottom p{margin:0}
.footer-legal{display:flex;flex-wrap:wrap;gap:16px}
.footer-legal a{min-height:24px;display:inline-flex;align-items:center}
.reveal{transition:opacity var(--time-enter) var(--ease),transform var(--time-enter) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:240px;overflow:hidden;max-width:100%;margin-top:24px;margin-bottom:32px}
#server-status>*{max-width:100%;min-width:0}
@media(max-width:1180px){
  .topbar-in{gap:16px}
  .tab{padding:0 9px;font-size:13.5px}
  .tab::after{left:9px;right:9px}
  .brand-zh{display:none}
}
@media(max-width:1080px){
  .tabs{display:none}
  .menu-toggle{display:inline-flex}
  .nav-tools{margin-left:auto}
  .topbar-in{gap:8px}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .preview-header .tabs{display:block;order:3;width:100%;overflow-x:auto;border-top:1px solid var(--border)}
  .preview-header .topbar-in{flex-wrap:wrap;padding-top:8px}
  .preview-header .tabs ul,.preview-header .tab{height:44px}
}
@media(max-width:768px){
  :root{--gutter:16px;--section-space:48px}
  h1{font-size:36px}
  h2{font-size:28px}
  h3{font-size:22px}
  .topbar{padding-inline:16px}
  .notice{gap:10px;padding-inline:14px;font-size:12.5px}
  .notice-text strong{display:none}
  .btn{min-height:46px;padding:10px 18px;font-size:var(--text-base)}
  .grid{grid-template-columns:minmax(0,1fr)}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .lang span{display:none}
  .topbar-in{padding-inline:10px;gap:6px}
  .nav-tools{margin-left:auto;gap:4px}
  .login{padding-inline:12px}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:24px}
  .tilt,[data-tilt]{transform:none!important}
  .decoration,.stripe-halo{max-width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}