:root{
  --bg:#E7F0FA;
  --hero-top:#EEF5FC;
  --hero-bottom:#E2ECF8;
  --panel:#F7FBFF;
  --panel-2:#D9E7F5;
  --border:#C9D9EC;
  --accent:#1590E8;
  --accent-dark:#0B63B8;
  --text:#0F1E33;
  --text-2:#2A3B55;
  --muted:#52627A;
  --success:#1FA971;
  --warn:#D98E12;
  --error:#D9364A;
  --board-top:#CFE6FA;
  --board-bottom:#9FCDF2;
  --hill-mint:#CDEBDD;
  --hill-blue:#B7D8F4;
  --hill-white:#F7FBFF;
  --tint-mint:#DDF3EA;
  --tint-lilac:#ECE6FB;
  --tint-peach:#FDEBDD;
  --tint-ice:#DCEBFA;
  --tint-gray:#E4EAF1;
  --tint-rose:#F9E2E9;
  --ink-mint:#137A52;
  --ink-lilac:#6748CC;
  --ink-peach:#A55F08;
  --ink-rose:#A63256;
  --note:#FFF5D2;
  --note-edge:#EEDB98;
  --note-ink:#5E4A12;
  --white:#FFFFFF;
  --col-side:#EEF4FB;
  --bar-bottom:#EDF3FA;
  --on-dark:#F2F7FD;
  --on-dark-muted:#9FB3CC;
  --on-dark-line:rgb(255 255 255 / .22);
  --glass:rgb(247 251 255 / .72);
  --glass-shell:rgb(247 251 255 / .52);
  --glass-edge:rgb(255 255 255 / .92);
  --halo:rgb(255 255 255 / .8);
  --halo-edge:rgb(201 217 236 / .55);
  --cross:rgb(255 255 255 / .55);
  --glow:rgb(255 255 255 / .62);
  --line-soft:rgb(201 217 236 / .7);
  --accent-08:rgb(21 144 232 / .08);
  --accent-12:rgb(21 144 232 / .12);
  --accent-20:rgb(21 144 232 / .20);
  --accent-35:rgb(21 144 232 / .35);
  --accent-dark-45:rgb(11 99 184 / .45);
  --white-22:rgb(255 255 255 / .22);
  --white-35:rgb(255 255 255 / .35);
  --success-16:rgb(31 169 113 / .16);
  --ink-15:rgb(15 30 51 / .15);
  --ink-30:rgb(15 30 51 / .30);
  --veil:rgb(15 30 51 / .36);
  --flag-red:#D52B35;
  --flag-white:#FFFFFF;
  --flag-blue:#2F3F8F;
  --flag-black:#1C1C22;
  --flag-gold:#F3C431;
  --flag-edge:rgb(15 30 51 / .16);
  --clear:transparent;
  --r-board:40px;
  --r-shell:30px;
  --r-win:22px;
  --r-card:12px;
  --r-pill:999px;
  --r-circle:50%;
  --r-xs:3px;
  --r-sm:6px;
  --r-badge:7px;
  --r-row:9px;
  --r-icon:10px;
  --r-mobile:24px;
  --r-feature:18px;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --gutter:24px;
  --wrap:1200px;
  --head-height:94px;
  --anchor-offset:110px;
  --toc-offset:174px;
  --shadow-card:inset 0 1px 0 var(--white),0 20px 52px -20px var(--accent-20);
  --shadow-soft:0 30px 80px var(--accent-12),0 6px 18px var(--accent-08);
  --ease:cubic-bezier(.2,.7,.2,1);
}
*{box-sizing:border-box;margin:0;padding:0}
html{background:var(--bg);scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{font-family:var(--font-body);font-size:15px;line-height:1.6;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
ul{list-style:none}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--accent-dark);outline-offset:4px}
::selection{background:var(--accent-20);color:var(--text)}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:800;color:var(--text);text-wrap:balance}
h1{font-size:clamp(52px,4.65vw,66px);line-height:1.12;letter-spacing:-.02em}
h2{font-size:clamp(28px,3vw,40px);line-height:1.25;letter-spacing:-.02em}
h3{font-size:22px;line-height:1.35}
p{overflow-wrap:break-word}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--panel-2);border-radius:var(--r-card)}
pre code{white-space:pre;overflow-wrap:normal}
button,a,summary{-webkit-tap-highlight-color:var(--accent-12)}
.wrap{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:72px;padding-bottom:72px}
.stack>*+*{margin-top:20px}
.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))}
.panel,.card{background:var(--panel);border:1px solid var(--border);border-radius:var(--r-win);box-shadow:var(--shadow-card);padding:28px;min-width:0}
.panel{border-radius:var(--r-shell)}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.no-break{white-space:nowrap}
.prose{max-width:800px;min-width:0;margin-inline:auto;font-size:16px;line-height:1.9}
.prose p,.prose ul,.prose ol,.prose pre,.prose table{margin-block:20px}
.prose h2{margin-top:48px;margin-bottom:20px}
.prose h3{margin-top:32px;margin-bottom:16px}
.prose ul{list-style:disc;padding-left:24px}
.prose ol{padding-left:24px}
.prose a{color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.prose code{background:var(--panel-2);border-radius:var(--r-xs);padding:2px 4px}
.prose pre code{padding:0;background:var(--clear)}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.btn,.btn-primary,.btn-ghost,.btn-secondary{display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;min-height:44px;gap:10px;padding:10px 24px;border-radius:var(--r-pill);font-weight:700;white-space:nowrap;border:1px solid var(--border);background:var(--panel);color:var(--text);text-align:center}
.btn svg,.btn-secondary svg{width:18px;height:18px}
.btn-primary{gap:14px;height:54px;padding:0 9px 0 32px;background:linear-gradient(180deg,var(--accent),var(--accent-dark));border:0;color:var(--white);font-size:17px;font-weight:800;letter-spacing:.01em;box-shadow:inset 0 1px 0 var(--white-35),0 0 0 8px var(--halo),0 0 0 9px var(--halo-edge),0 20px 36px -12px var(--accent-dark-45);transition:transform .2s ease}
.btn-primary:hover{transform:translateY(-1px)}
.btn-primary:active{transform:translateY(0)}
.btn-arrow{width:36px;height:36px;border-radius:var(--r-circle);background:var(--white-22);display:grid;place-items:center;box-shadow:inset 0 0 0 1px var(--white-35);flex:none}
.btn-arrow svg{width:18px;height:18px}
.btn-ghost{height:54px;padding:0 28px;border:1.5px solid var(--border);font-size:16px;box-shadow:inset 0 1px 0 var(--white),0 12px 24px -16px var(--accent-35)}
.btn:hover,.btn-ghost:hover,.btn-secondary:hover{border-color:var(--accent-35);background:var(--hero-top)}
.btn:disabled,.btn-primary:disabled,.btn-secondary:disabled{opacity:.55;box-shadow:none;transform:none}
.btn.is-focus{outline:2px solid var(--accent-dark);outline-offset:4px}
.reveal{transition:opacity .35s ease,transform .35s 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%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}
#site-header,.header-host{position:sticky;top:0;z-index:100}
.announce{height:34px;background:var(--text);color:var(--on-dark);display:flex;align-items:center;justify-content:center;gap:12px;font-size:13.5px;padding:0 16px}
.announce .new{font:700 11px/1 var(--font-mono);letter-spacing:.08em;color:var(--white);background:linear-gradient(180deg,var(--accent),var(--accent-dark));padding:5px 8px;border-radius:var(--r-badge);box-shadow:inset 0 0 0 1px var(--white-35)}
.announce .ann-muted{color:var(--on-dark-muted)}
.announce a{display:inline-flex;align-items:center;justify-content:center;min-height:24px;gap:6px;font-weight:600;padding-left:12px;border-left:1px solid var(--on-dark-line)}
.announce a svg{width:14px;height:14px}
.announce a:hover{color:var(--white)}
.site-head{position:relative;z-index:103;background:var(--hero-top);border-bottom:1px solid var(--line-soft)}
.head-inner{max-width:1280px;height:60px;margin:0 auto;padding:0 32px;display:flex;align-items:center;gap:24px;flex-wrap:nowrap}
.brand{display:flex;align-items:center;gap:10px;flex:none}
.brand img{width:32px;height:32px}
.brand-word{font:800 20px/1 var(--font-display);letter-spacing:-.02em;color:var(--text)}
.brand-sub{font-size:13px;font-weight:500;color:var(--muted);padding-left:10px;border-left:1px solid var(--border);line-height:1}
.nav{flex:1;min-width:0;font-size:14px;font-weight:500;color:var(--muted)}
.nav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:20px}
.nav li{flex:none}
.nav a{display:inline-flex;align-items:center;min-height:32px;white-space:nowrap}
.nav a:hover{color:var(--text)}
.nav a[aria-current="page"]{color:var(--text);font-weight:700}
.head-tools{margin-left:auto;display:flex;align-items:center;gap:12px;flex-shrink:0}
.lang-picker{position:relative}
.lang-button{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:38px;width:auto;padding:7px 10px;border:0;background:var(--clear);font-size:14px;color:var(--muted);border-radius:var(--r-icon);white-space:nowrap}
.lang-button span{white-space:nowrap}
.lang-button:hover{background:var(--panel-2);color:var(--text)}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:110;min-width:174px;padding:8px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:var(--shadow-soft)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-row);white-space:nowrap}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-2)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:38px;min-height:38px;padding:0 18px;border-radius:var(--r-pill);background:var(--panel);border:1px solid var(--border);font-size:14px;font-weight:700;color:var(--text);box-shadow:inset 0 1px 0 var(--white),0 8px 18px -10px var(--accent-35);white-space:nowrap}
.login:hover{border-color:var(--accent-35)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--r-icon);background:var(--panel);color:var(--text)}
.menu-line{display:block;width:20px;height:2px;background:currentColor;border-radius:var(--r-xs)}
.mobile-drawer{position:fixed;top:var(--head-height);right:0;left:0;z-index:102;height:calc(100dvh - var(--head-height));max-height:calc(100dvh - var(--head-height));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:16px var(--gutter) 32px}
.mobile-drawer a{display:flex;width:100%;align-items:center;min-height:44px;padding:12px 16px;border-radius:var(--r-card);font-weight:600}
.mobile-drawer a:hover,.mobile-drawer a[aria-current="page"]{background:var(--panel-2)}
.drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--border)}
.menu-veil{position:fixed;inset:var(--head-height) 0 0;z-index:101;background:var(--veil);border:0;width:100%;height:calc(100dvh - var(--head-height))}
html.nav-open{overflow:hidden}
.site-footer{background:var(--panel-2);border-top:1px solid var(--border);padding-top:56px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:48px}
.footer-grid>*{min-width:0}
.footer-brand p{color:var(--muted);max-width:340px;margin-top:20px}
.footer-heading{font-size:15px;font-weight:800;margin-bottom:12px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 20px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;color:var(--text-2);font-size:14px}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;margin-top:32px;padding-top:24px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:16px;margin-top:20px;color:var(--muted);font-size:13px}
.footer-legal{display:flex;gap:24px}
@media(min-width:1181px){.head-inner{gap:24px}.nav ul{gap:22px}}
@media(max-width:1180px){.head-inner{gap:18px;padding-inline:24px}.nav ul{gap:14px}.nav{font-size:13px}.head-tools{gap:8px}.brand-sub{display:none}}
@media(max-width:1080px){.nav{display:none}.menu-toggle{display:flex}.head-tools{margin-left:auto}.head-inner{padding-inline:20px}.footer-grid{gap:28px}}
@media(min-width:1081px){.mobile-drawer,.menu-veil{display:none!important}}
@media(max-width:768px){
  h1{font-size:clamp(28px,5vw,40px);line-height:1.15}
  .grid-three{grid-template-columns:1fr}
  .grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
  .sec{padding-top:48px;padding-bottom:48px}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1 / -1}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .announce{font-size:12px;gap:8px}
  .announce .ann-muted{display:none}
  .announce a{padding-left:8px}
  .head-inner{gap:8px;padding-inline:16px}
  .brand{gap:6px}
  .brand img{width:26px;height:26px}
  .brand-word{font-size:17px}
  .head-tools{gap:4px;margin-left:auto}
  .login{padding-inline:12px;font-size:13px}
  .lang-button{font-size:12px;padding-inline:6px}
  .panel,.card{padding:20px}
  .footer-grid{grid-template-columns:1fr}
  .footer-brand{grid-column:auto}
  .tilt,.decorative-tilt,[data-tilt]{transform:none}
  [data-hero-visual],.decoration,.stripe-halo{max-width:100%}
}
@media(max-width:359px){
  .brand-word{font-size:15px}.brand img{width:24px;height:24px}
  .head-inner{padding-inline:12px}.login{padding-inline:9px}
  .lang-button{font-size:11px;padding-inline:4px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  .btn-primary{transition:none}
  .btn-primary:hover{transform:none}
}