:root{
  --bg:#E6EEF7;--bg-panel:#F7FAFE;--bg-panel-2:#D8E4F1;--border:#C6D5E7;--accent:#2C3F96;--accent-dark:#1C2A6B;--text:#142033;--text-muted:#52627A;--success:#1F9D6B;--warn:#D9960F;--error:#D2453B;
  --sky:#1A9FE0;--cream:#F8E08E;--coral:#F0645A;--hero-top:#EEF4FB;--hero-bottom:#DCE7F3;--white:#FFFFFF;--flag-red:#D7353B;--flag-navy:#26306B;--flag-white:#FFFFFF;
  --accent-rgb:44 63 150;--accent-dark-rgb:28 42 107;--sky-rgb:26 159 224;--success-rgb:31 157 107;--warn-rgb:217 150 15;--white-rgb:255 255 255;--text-rgb:20 32 51;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Apple SD Gothic Neo","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Apple SD Gothic Neo","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --weight-display:800;--weight-heading:700;--weight-body:400;
  --r-pill:999px;--r-bar:28px;--r-stage:32px;--r-core:30px;--r-card:20px;--r-small:12px;--r-mark:10px;--r-circle:50%;
  --hl:inset 0 1px 0 rgb(var(--white-rgb) / .95);
  --sh-xs:0 4px 12px rgb(var(--accent-rgb) / .08),0 1px 2px rgb(var(--accent-rgb) / .06);
  --sh-soft:0 12px 28px rgb(var(--accent-rgb) / .10),0 2px 6px rgb(var(--accent-rgb) / .06);
  --sh-float:0 18px 38px -8px rgb(var(--accent-rgb) / .22),0 3px 8px rgb(var(--accent-rgb) / .08);
  --sh-stage:0 36px 84px -14px rgb(var(--accent-rgb) / .12),0 6px 18px rgb(var(--accent-rgb) / .06);
  --gutter:32px;--content-width:1200px;--header-height:68px;--anchor-space:84px;--toc-space:152px;--section-space:72px;--ease:ease;--fast:.2s;--reveal-duration:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-space);scroll-behavior:smooth}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font:var(--weight-body) 16px/1.6 var(--font-body);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
button,a,summary,input,select,textarea{touch-action:manipulation}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
figure{margin:0}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:var(--weight-display);line-height:1.25;text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,4.45vw,64px);line-height:1.1;letter-spacing:-.02em}
h2{font-size:clamp(26px,3vw,36px);letter-spacing:-.02em}
h3{font-size:22px}
p{margin:0 0 1em}
ul,ol{padding-left:1.5em}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;border-radius:var(--r-small);background:var(--bg-panel-2);font-family:var(--font-mono)}
pre code{overflow-wrap:normal;white-space:pre}
hr{border:0;border-top:1px solid var(--border);margin-block:32px}
.no-break{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.wrap{width:100%;max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:860px;margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.grid{display:grid;gap:24px}
.grid>*{min-width:0}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-five{grid-template-columns:repeat(5,minmax(0,1fr))}
.muted{color:var(--text-muted)}
.accent{color:var(--accent)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.kicker{font-size:13px;font-weight:700;color:var(--accent);letter-spacing:.04em}
.panel,.card{min-width:0;padding:28px;border-radius:var(--r-card);background:var(--bg-panel);box-shadow:var(--hl),var(--sh-soft)}
.card{transition:transform var(--fast) var(--ease),box-shadow var(--fast) var(--ease)}
.card:hover{box-shadow:var(--hl),var(--sh-float)}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose li{line-height:1.85}
.prose a{color:var(--accent);text-decoration:underline;text-underline-offset:3px}
.prose h2{margin-top:2em}
.prose h3{margin-top:1.5em}
.prose img{border-radius:var(--r-small)}
.ico{fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.ico-fill{fill:currentColor;stroke:none}
.icon{width:20px;height:20px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:52px;padding:10px 30px;border:0;border-radius:var(--r-pill);font-size:16px;font-weight:700;letter-spacing:.01em;white-space:nowrap;flex-shrink:0;transition:transform var(--fast) var(--ease),box-shadow var(--fast) var(--ease),background-color var(--fast) var(--ease)}
.btn svg{width:18px;height:18px}
.btn-main,.btn-primary{color:var(--white);background:linear-gradient(120deg,var(--sky) 0%,var(--accent) 78%);box-shadow:0 14px 28px -6px rgb(var(--accent-rgb) / .40),0 4px 10px rgb(var(--sky-rgb) / .18),inset 0 1px 0 rgb(var(--white-rgb) / .30)}
.btn-main:hover,.btn-primary:hover{transform:translateY(-2px);box-shadow:var(--sh-float)}
.btn-line,.btn-secondary{color:var(--accent);border:1.5px solid var(--accent);background:rgb(var(--white-rgb) / .5)}
.btn-line:hover,.btn-secondary:hover{background:var(--white);transform:translateY(-2px)}
.btn:active{transform:translateY(0)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.5;box-shadow:none;transform:none;pointer-events:none}
.btn-small{min-height:40px;padding:7px 18px;font-size:14px}
.cta-row{margin-top:22px;display:flex;flex-wrap:wrap;justify-content:center;gap:14px}
#site-header{position:relative;z-index:40;min-height:var(--header-height)}
.masthead{position:relative;z-index:43;background:rgb(var(--white-rgb) / .55);border-bottom:1px solid rgb(var(--accent-rgb) / .08);backdrop-filter:saturate(1.2) blur(10px);-webkit-backdrop-filter:saturate(1.2) blur(10px)}
.masthead-in{max-width:1320px;margin:0 auto;padding-inline:32px;height:var(--header-height);display:flex;flex-wrap:nowrap;align-items:center;gap:20px}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;font-family:var(--font-display);font-weight:800;font-size:20px;letter-spacing:-.02em;color:var(--text);min-height:44px}
.brand img{width:34px;height:34px;flex-shrink:0;border-radius:var(--r-mark)}
.brand-zh{font-weight:500;color:var(--text-muted)}
.desktop-nav{flex:1;min-width:0}
.navlist{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:12px;justify-content:flex-end}
.navlist li{flex-shrink:0;min-width:0}
.navlist a{display:flex;align-items:center;gap:6px;padding:8px 6px;border-radius:var(--r-pill);font-size:13px;font-weight:500;color:var(--text-muted);white-space:nowrap;transition:color var(--fast),background-color var(--fast)}
.navlist a svg{display:none;width:16px;height:16px}
.navlist a:hover{color:var(--accent);background:rgb(var(--accent-rgb) / .06)}
.navlist a[aria-current="page"]{color:var(--accent);font-weight:700;background:var(--bg-panel);box-shadow:var(--sh-xs),var(--hl)}
.tools{display:flex;align-items:center;gap:10px;flex-shrink:0}
.language{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:38px;width:auto;padding:0 14px;border-radius:var(--r-pill);border:1px solid var(--border);background:rgb(var(--white-rgb) / .6);color:var(--text);font-size:14px;white-space:nowrap}
.lang svg{width:16px;height:16px;color:var(--text-muted)}
.lang-label{white-space:nowrap}
.lang-panel{position:absolute;z-index:50;right:0;top:calc(100% + 10px);width:190px;padding:8px;border-radius:var(--r-card);background:var(--bg-panel);box-shadow:var(--sh-float)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-small)}
.lang-panel a:hover,.lang-panel a[aria-current]{color:var(--accent);background:var(--bg-panel-2)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:38px;padding:0 20px 0 16px;border-radius:var(--r-pill);background:var(--accent);color:var(--white);font-size:14px;font-weight:700;white-space:nowrap;box-shadow:0 8px 18px rgb(var(--accent-rgb) / .26),inset 0 1px 0 rgb(var(--white-rgb) / .25);transition:transform var(--fast),background-color var(--fast)}
.login svg{width:16px;height:16px}
.login:hover{background:var(--accent-dark);transform:translateY(-1px)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--r-pill);color:var(--accent);background:var(--bg-panel)}
.menu-toggle svg{width:20px;height:20px}
.mobile-drawer{display:none;position:fixed;z-index:42;top:var(--header-height);right:0;left:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:16px var(--gutter) 32px}
.navlist-mobile{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:0}
.mobile-drawer a{display:flex;align-items:center;gap:10px;width:100%;min-height:44px;padding:8px 16px;border-radius:var(--r-small);font-weight:600}
.mobile-drawer a svg{width:18px;height:18px}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{background:var(--bg-panel-2);color:var(--accent)}
.drawer-languages{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));border-top:1px solid var(--border);margin-top:12px;padding-top:12px}
.nav-veil{position:fixed;z-index:41;inset:var(--header-height) 0 0;background:rgb(var(--text-rgb) / .25)}
.site-footer{background:var(--bg-panel-2);border-top:1px solid rgb(var(--accent-rgb) / .08)}
.footer-grid{display:grid;grid-template-columns:1.35fr 1fr 1fr;gap:40px;padding-top:48px;padding-bottom:36px}
.footer-grid>*{min-width:0}
.footer-brand p{max-width:320px;margin-top:16px;font-size:14px;color:var(--text-muted)}
.footer-title{font-size:16px;margin:0 0 12px}
.footer-links{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;font-size:14px}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent);text-decoration:underline}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;padding-bottom:20px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;border-top:1px solid var(--border);padding-top:20px;padding-bottom:28px;font-size:13px;color:var(--text-muted)}
.footer-bottom p{margin:0}
.footer-legal{display:flex;gap:18px;flex-wrap:wrap}
.reveal{transition:opacity var(--reveal-duration) var(--ease),transform var(--reveal-duration) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-width:0;max-width:100%;min-height:120px;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:32px}
@media(min-width:901px) and (max-width:1250px){
  .masthead-in{gap:12px;padding-inline:24px}
  .navlist{gap:12px}
  .navlist a{padding:8px 6px;font-size:13px;gap:6px}
  .navlist a svg{width:14px;height:14px}
  .tools{gap:6px}
  .lang{padding-inline:10px}
}
@media(max-width:1100px){
  .desktop-nav{display:none}
  .tools{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .mobile-drawer:not([hidden]){display:block}
}
@media(max-width:768px){
  :root{--gutter:16px;--section-space:48px}
  h1{font-size:38px}
  .grid-three{grid-template-columns:minmax(0,1fr)}
  .grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
  .masthead-in{padding-inline:16px;gap:10px}
  .tools{margin-left:auto;gap:6px}
  .brand{gap:7px;font-size:18px}
  .lang{padding-inline:10px;min-height:38px}
  .login{padding-inline:12px}
  .login svg{display:none}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:28px}
  .btn{min-height:48px;padding-inline:24px;font-size:15px}
  .panel,.card{padding:22px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,.decor-tilt,[data-tilt]{transform:none}
  [data-decor],.canopy,.stage{max-width:100%}
}
@media(max-width:380px){
  .masthead-in{padding-inline:12px;gap:6px}
  .brand{font-size:16px;gap:5px}
  .brand img{width:28px;height:28px}
  .lang{font-size:12px;padding-inline:7px;gap:4px}
  .lang svg{display:none}
  .login{padding-inline:10px;font-size:13px}
  .tools{gap:4px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}