:root{
  --color-bg:#E4E9F7;
  --color-panel:#F5F8FE;
  --color-inset:#D8E0F2;
  --color-paper:#F1F4FB;
  --color-border:#C6D1EA;
  --color-accent:#274BD6;
  --color-accent-dark:#1B37A6;
  --color-sky:#7CC0F8;
  --color-text:#141B33;
  --color-muted:#4E5A7A;
  --color-success:#1B9E6C;
  --color-warn:#E0A626;
  --color-error:#D2453F;
  --color-yellow:#F5C445;
  --color-pink:#F7A8C4;
  --color-hero-top:#DDE4F5;
  --color-hero-bottom:#E9EDF9;
  --color-circle-a:#CFDBF3;
  --color-circle-b:#DDE6F8;
  --color-blue-soft:#DCE6FA;
  --color-yellow-soft:#FBF3DC;
  --color-pink-soft:#FBE4EC;
  --color-side:#EEF2FB;
  --color-white:#FFFFFF;
  --color-overlay:rgba(20,27,51,.38);
  --color-success-soft:rgba(27,158,108,.12);
  --color-success-ring:rgba(27,158,108,.14);
  --color-button-shine:rgba(255,255,255,.25);
  --color-highlight:rgba(255,255,255,.9);
  --color-line-soft:rgba(198,209,234,.7);
  --shadow-soft:rgba(39,75,214,.12);
  --shadow-deep:rgba(39,75,214,.14);
  --shadow-button:rgba(39,75,214,.28);
  --shadow-small:rgba(39,75,214,.08);
  --shadow-phone:rgba(39,75,214,.16);
  --shadow-switch:rgba(20,27,51,.2);
  --font-display:Georgia,'Noto Serif SC','Songti SC','STSong','SimSun','Times New Roman',serif;
  --font-body:'Inter','Noto Sans SC','PingFang SC','Microsoft YaHei','Hiragino Sans GB',system-ui,sans-serif;
  --font-mono:'JetBrains Mono','SFMono-Regular',Menlo,Consolas,'Liberation Mono',monospace;
  --radius-xs:6px;
  --radius-sm:8px;
  --radius-button:12px;
  --radius-card:24px;
  --radius-window:22px;
  --radius-phone:28px;
  --radius-section:40px;
  --radius-pill:999px;
  --header-height:62px;
  --content-width:1180px;
  --reading-width:760px;
  --gutter:24px;
  --section-space:88px;
  --focus-size:2px;
  --toc-offset:126px;
  --transition-fast:180ms ease;
  --transition-base:260ms ease;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:calc(var(--header-height) + 16px);background:var(--color-bg)}
body,h1,h2,h3,h4,p,ul,ol,dl,dd,figure,blockquote{margin:0}
body{min-width:0;overflow-x:clip;background:var(--color-bg);color:var(--color-text);font-family:var(--font-body);font-size:15px;line-height:1.65;-webkit-font-smoothing:antialiased}
img,svg,video,canvas{display:block;max-width:100%}
img{height:auto}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
a{color:inherit;text-decoration:none}
ul[role="list"],ol[role="list"],.plain-list{list-style:none;padding:0}
table{border-collapse:collapse;border-spacing:0}
code,kbd,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch}
h1,h2,h3,h4{font-weight:700;line-height:1.2;text-wrap:balance}
h1,.display-title{font-family:var(--font-display);font-size:clamp(52px,5.6vw,68px);font-weight:600;line-height:1.1;letter-spacing:-.02em}
h2{font-family:var(--font-display);font-size:clamp(32px,4vw,46px);letter-spacing:-.02em}
h3{font-size:20px;letter-spacing:-.01em}
p+ p{margin-top:1em}
::selection{background:var(--color-blue-soft);color:var(--color-accent-dark)}
:where(a,button,input,select,textarea,summary,[role="tab"]):focus-visible{outline:var(--focus-size) solid var(--color-accent);outline-offset:3px}
.wrap{width:100%;max-width:calc(var(--content-width) + var(--gutter) * 2);margin-inline:auto;padding-inline:var(--gutter)}
.reading{width:100%;max-width:calc(var(--reading-width) + var(--gutter) * 2);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.section-head{max-width:760px;margin:0 auto 40px;text-align:center}
.section-kicker{display:block;margin-bottom:10px;color:var(--color-accent);font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase}
.section-copy{margin-top:14px;color:var(--color-muted);font-size:16px}
.no-break{white-space:nowrap}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.muted{color:var(--color-muted)}
.text-accent{color:var(--color-accent)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.icon{width:20px;height:20px;flex:0 0 auto;color:currentColor}
.flag-icon{width:22px;height:15px;flex:0 0 auto;border-radius:4px;box-shadow:0 0 0 1px var(--color-line-soft);overflow:hidden}
.flag-icon svg{width:22px;height:15px}
.panel,.card{min-width:0;background:var(--color-panel);border:1px solid var(--color-line-soft);border-radius:var(--radius-card);box-shadow:0 18px 40px var(--shadow-soft),inset 0 0 0 1px var(--color-highlight)}
.card{padding:26px}
.card-hover{transition:transform var(--transition-fast),box-shadow var(--transition-fast)}
.card-hover:hover{transform:translateY(-2px);box-shadow:0 24px 46px var(--shadow-soft),inset 0 0 0 1px var(--color-highlight)}
.btn{min-height:48px;min-width:24px;padding:0 28px;border:1px solid transparent;border-radius:var(--radius-button);display:inline-flex;align-items:center;justify-content:center;gap:8px;font-weight:700;font-size:15px;line-height:1.2;transition:transform var(--transition-fast),box-shadow var(--transition-fast),color var(--transition-fast),background var(--transition-fast),border-color var(--transition-fast)}
.btn:hover{transform:translateY(-1px)}
.btn-primary{color:var(--color-white);background:linear-gradient(135deg,var(--color-accent),var(--color-accent) 55%,var(--color-sky) 165%);box-shadow:0 10px 24px var(--shadow-button),inset 0 1px 0 var(--color-button-shine)}
.btn-primary:hover{box-shadow:0 14px 28px var(--shadow-button),inset 0 1px 0 var(--color-button-shine)}
.btn-secondary{background:var(--color-panel);border-color:var(--color-border);color:var(--color-text)}
.btn-secondary:hover{border-color:var(--color-accent);color:var(--color-accent)}
.btn-small{min-height:38px;padding-inline:18px;font-size:13px}
.btn[aria-disabled="true"],.btn:disabled{opacity:.55;cursor:not-allowed;transform:none}
.reveal{transition:opacity .6s ease,transform .6s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
html.nav-open{overflow:hidden}

.site-header{height:var(--header-height);position:relative;z-index:50;background:var(--color-panel);border-bottom:1px solid var(--color-border)}
.header-inner{height:100%;display:flex;align-items:center;gap:24px}
.brand{min-width:0;display:inline-flex;align-items:center;gap:10px;font-size:19px;font-weight:800;letter-spacing:-.01em;flex:0 0 auto}
.brand img{width:32px;height:32px;border-radius:9px;box-shadow:0 6px 14px var(--shadow-soft)}
.brand-local{color:var(--color-muted);font-weight:500}
.desktop-nav{height:100%;display:flex;align-items:stretch}
.desktop-nav a{position:relative;min-height:44px;padding-inline:10px;display:inline-flex;align-items:center;color:var(--color-muted);font-size:13px;font-weight:600;white-space:nowrap}
.desktop-nav a:hover,.desktop-nav a[aria-current="page"]{color:var(--color-text)}
.desktop-nav a[aria-current="page"]::after{content:"";position:absolute;left:10px;right:10px;bottom:-1px;height:3px;border-radius:3px 3px 0 0;background:var(--color-accent)}
.header-tools{margin-left:auto;display:flex;align-items:center;gap:10px;flex:0 0 auto}
.login-link{min-height:36px;padding-inline:17px;border:1.5px solid var(--color-accent);border-radius:var(--radius-pill);display:inline-flex;align-items:center;justify-content:center;color:var(--color-accent);font-size:14px;font-weight:700;white-space:nowrap}
.login-link:hover{background:var(--color-accent);color:var(--color-white)}
.language-picker{position:relative}
.language-button,.menu-button{min-width:44px;min-height:44px;border:0;background:transparent;display:inline-flex;align-items:center;justify-content:center;border-radius:var(--radius-button)}
.language-button{gap:5px;color:var(--color-muted);font-size:13px}
.language-menu{position:absolute;top:calc(100% + 8px);right:0;width:160px;padding:7px;background:var(--color-panel);border:1px solid var(--color-border);border-radius:14px;box-shadow:0 18px 40px var(--shadow-soft)}
.language-menu[hidden]{display:none}
.language-menu a{min-height:40px;padding:8px 10px;border-radius:8px;display:flex;align-items:center}
.language-menu a:hover,.language-menu a[aria-current="true"]{background:var(--color-blue-soft);color:var(--color-accent)}
.menu-button{display:none}
.menu-lines,.menu-lines::before,.menu-lines::after{width:20px;height:2px;border-radius:2px;background:var(--color-text);display:block}
.menu-lines{position:relative}
.menu-lines::before,.menu-lines::after{content:"";position:absolute;left:0}
.menu-lines::before{top:-6px}.menu-lines::after{top:6px}
.mobile-nav{display:none}
.nav-veil{display:none}

.site-footer{position:relative;background:var(--color-accent-dark);color:var(--color-white);overflow-x:clip}
.footer-grid{padding-top:64px;padding-bottom:42px;display:grid;grid-template-columns:1.2fr 1fr 1.25fr;gap:54px}
.footer-brand p{max-width:390px;margin-top:16px;color:var(--color-blue-soft)}
.footer-brand .brand-local{color:var(--color-blue-soft)}
.footer-title{margin-bottom:14px;font-size:13px;letter-spacing:.08em;color:var(--color-sky)}
.footer-links{display:flex;flex-wrap:wrap;gap:8px 16px}
.footer-links a{min-height:28px;display:inline-flex;align-items:center;color:var(--color-blue-soft)}
.footer-links a:hover{color:var(--color-white)}
.footer-legal{padding-top:18px;padding-bottom:24px;border-top:1px solid var(--color-border);display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;color:var(--color-blue-soft);font-size:13px}
.footer-legal nav{display:flex;gap:16px;flex-wrap:wrap}
.footer-orb{position:absolute;right:-80px;top:-80px;width:220px;height:220px;border-radius:50%;background:var(--color-accent);opacity:.35;pointer-events:none}

#server-status{position:relative;display:block;overflow:hidden;margin-top:32px;margin-bottom:32px;max-width:100%}
#server-status+*{margin-top:32px}

.prose{min-width:0;color:var(--color-text)}
.prose h2,.prose h3{scroll-margin-top:var(--toc-offset)}
.prose h2{margin-top:2em;margin-bottom:.7em}
.prose h3{margin-top:1.6em;margin-bottom:.55em}
.prose p,.prose ul,.prose ol,.prose blockquote,.prose pre,.prose table{margin-top:1em}
.prose ul,.prose ol{padding-left:1.4em}
.prose li+li{margin-top:.45em}
.prose a:not(.btn){color:var(--color-accent);text-decoration:underline;text-underline-offset:3px}
.prose pre{padding:18px;border-radius:14px;background:var(--color-text);color:var(--color-panel)}
body:has(.toc-tabs) section[id]{scroll-margin-top:var(--toc-offset)}

@media (max-width:1100px){
  .desktop-nav a{padding-inline:7px;font-size:12px}
  .header-inner{gap:14px}
}
@media (max-width:1024px){
  .desktop-nav{display:none}
  .header-tools{margin-left:auto}
  .menu-button{display:inline-flex}
  .language-picker{display:none}
  .mobile-nav{position:fixed;z-index:52;left:var(--gutter);right:var(--gutter);top:calc(var(--header-height) + 8px);max-height:calc(100dvh - var(--header-height) - 24px);overflow-y:auto;overscroll-behavior:contain;padding:10px;background:var(--color-panel);border:1px solid var(--color-border);border-radius:18px;box-shadow:0 24px 60px var(--shadow-deep)}
  .mobile-nav.is-open{display:block}
  .mobile-nav a{width:100%;min-height:44px;padding:10px 12px;border-radius:9px;display:flex;align-items:center;color:var(--color-muted);font-weight:600}
  .mobile-nav a:hover,.mobile-nav a[aria-current="page"]{background:var(--color-blue-soft);color:var(--color-accent)}
  .mobile-language{margin-top:8px;padding-top:8px;border-top:1px solid var(--color-border)}
  .nav-veil.is-open{position:fixed;z-index:49;inset:var(--header-height) 0 0;display:block;border:0;background:var(--color-overlay)}
}
@media (max-width:768px){
  :root{--gutter:20px;--section-space:68px}
  h1,.display-title{font-size:clamp(28px,9vw,40px);line-height:1.12}
  h2{font-size:clamp(28px,7vw,36px)}
  .footer-grid{grid-template-columns:1fr;gap:34px}
  .footer-legal{flex-direction:column}
}
@media (max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .wrap,.reading{padding-inline:var(--gutter)}
  .btn{min-height:44px;padding-inline:20px;font-size:14px}
  .card{padding:21px}
  .brand{font-size:17px}
  .brand img{width:30px;height:30px}
  .login-link{padding-inline:13px}
  .tilt-card,.is-tilted,[class*="decorative-tilt"]{transform:none!important}
  .absolute-decor,.page-halo,.stripe-halo{max-width:100%;display:none}
}
@media (max-width:360px){
  .header-inner{gap:6px}
  .login-link{padding-inline:10px;font-size:13px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1!important;transform:none!important}
}