:root{
  color-scheme:light;
  --bg:#E8ECF7;
  --bg-panel:#F6F8FD;
  --bg-panel-2:#DCE2F2;
  --border:#C9D1E8;
  --border-soft:#D9DFEF;
  --accent:#6246EA;
  --accent-dark:#4530C4;
  --ice:#38B6F5;
  --text:#161A2E;
  --text-muted:#565E7A;
  --text-faint:#7F87A4;
  --success:#1F9D6B;
  --warn:#B9791A;
  --error:#D2414E;
  --ink:#12142A;
  --ink-2:#1C1F3D;
  --ink-line:rgba(238,241,250,.18);
  --on-ink:#EEF1FA;
  --on-ink-muted:#A6ADCB;
  --white:#FFFFFF;
  --hero-top:#F1F4FB;
  --hero-bottom:#DDE3F3;
  --win-side:#EEF1FA;
  --dot:#C3CADF;
  --accent-tint:rgba(98,70,234,.08);
  --accent-tint-2:rgba(98,70,234,.13);
  --accent-ring:rgba(98,70,234,.18);
  --success-ring:rgba(31,157,107,.18);
  --trace:rgba(69,48,196,.13);
  --trace-fill:rgba(69,48,196,.05);
  --trace-opacity:.04;
  --pad-fill:#F1F4FB;
  --highlight:rgba(255,255,255,.92);
  --flag-red:#D6283C;
  --flag-blue:#1F3E8C;
  --flag-white:#FFFFFF;
  --flag-edge:rgba(22,26,46,.16);
  --veil:rgba(18,20,42,.38);
  --clear:transparent;
  --shadow-chip:0 1px 2px rgba(22,26,46,.05);
  --shadow-1:0 1px 2px rgba(22,26,46,.05),0 12px 28px rgba(98,70,234,.09);
  --shadow-2:0 2px 6px rgba(22,26,46,.05),0 32px 64px rgba(98,70,234,.10);
  --shadow-3:0 4px 10px rgba(22,26,46,.06),0 40px 80px rgba(98,70,234,.15);
  --shadow-cta:inset 0 1px 0 rgba(255,255,255,.22),0 12px 28px rgba(98,70,234,.12),0 2px 6px rgba(98,70,234,.12);
  --shadow-toggle:inset 0 1px 0 rgba(255,255,255,.32),inset 0 -3px 8px rgba(69,48,196,.30),0 10px 22px rgba(98,70,234,.22);
  --shadow-knob:0 2px 6px rgba(22,26,46,.18);
  --shadow-login:inset 0 1px 0 rgba(238,241,250,.18),0 4px 12px rgba(18,20,42,.16);
  --shadow-signup:inset 0 1px 0 rgba(238,241,250,.18),0 6px 14px rgba(18,20,42,.18);
  --shadow-window:inset 0 1px 0 #FFFFFF,0 0 0 1px #C9D1E8,0 2px 4px rgba(22,26,46,.05);
  --shadow-dot:inset 0 -1px 0 rgba(22,26,46,.08);
  --tray-inset:inset 0 2px 6px rgba(22,26,46,.06);
  --r-xs:4px;
  --r-sm:6px;
  --r:8px;
  --r-lg:10px;
  --r-round:50%;
  --r-pill:999px;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --gutter:24px;
  --content:1248px;
  --reading:800px;
  --section-space:80px;
  --toc-top:16px;
  --anchor-offset:100px;
  --duration:.16s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:16px;line-height:1.5;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
a{color:inherit;text-underline-offset:.2em}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,summary,a,input,select,textarea{-webkit-tap-highlight-color:var(--accent-tint)}
button{color:inherit}
button:disabled{cursor:not-allowed}
: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}
p{margin:0}
h1,h2,h3,h4{font-family:var(--font-display);color:inherit;text-wrap:balance}
h1{font-size:clamp(52px,5vw,72px);line-height:1.1;font-weight:900;letter-spacing:-.02em}
h2{font-size:clamp(28px,3vw,40px);line-height:1.25;font-weight:800;letter-spacing:-.015em}
h3{font-size:22px;line-height:1.35;font-weight:750}
h1,h2,h3{margin:0 0 20px}
ul,ol{padding-left:1.4em}
code,kbd,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:20px;border:1px solid var(--border);border-radius:var(--r);background:var(--bg-panel-2);font-size:14px}
pre code{overflow-wrap:normal;white-space:pre}
hr{border:0;border-top:1px solid var(--border);margin:32px 0}
.wrap{width:100%;max-width:var(--content);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:var(--reading);margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.stack>*+*{margin-top:20px}
.grid{display:grid;gap:24px}
.grid>*{min-width:0}
.grid--three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--two{grid-template-columns:repeat(2,minmax(0,1fr))}
.flex-row{display:flex;align-items:center;flex-wrap:wrap;gap:12px}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono)}
.no-break{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.panel,.card{min-width:0;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:inset 0 1px 0 var(--highlight),var(--shadow-1);padding:24px}
.tray{min-width:0;padding:16px;background:var(--bg-panel-2);border-radius:var(--r-lg);box-shadow:var(--tray-inset)}
.btn,.xn-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 22px;border:1px solid var(--clear);border-radius:var(--r);font-size:16px;font-weight:650;line-height:1.3;text-align:center;text-decoration:none;flex-shrink:0;white-space:nowrap;transition:background var(--duration),border-color var(--duration),transform var(--duration),box-shadow var(--duration)}
.btn svg,.xn-btn svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
.btn-primary,.xn-btn--primary{background:var(--accent);color:var(--white);box-shadow:var(--shadow-cta)}
.btn-primary:hover,.xn-btn--primary:hover,.btn-primary.is-hover{background:var(--accent-dark);transform:translateY(-1px)}
.btn-secondary,.xn-btn--ghost{background:var(--bg-panel);color:var(--text);border-color:var(--border);box-shadow:inset 0 1px 0 var(--highlight),var(--shadow-chip)}
.btn-secondary:hover,.xn-btn--ghost:hover{border-color:var(--accent);color:var(--accent-dark)}
.btn:active,.xn-btn:active,.btn.is-pressed{transform:translateY(1px);box-shadow:var(--tray-inset)}
.btn:disabled{background:var(--bg-panel-2);color:var(--text-muted);border-color:var(--border);box-shadow:none;transform:none}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.btn-small{min-height:36px;padding-inline:14px;font-size:14px}
.badge{display:inline-flex;align-items:center;gap:8px;max-width:100%;padding:5px 10px;background:var(--accent-tint);border:1px solid var(--accent-ring);border-radius:var(--r-sm);font-family:var(--font-mono);font-size:12px;color:var(--accent-dark);overflow-wrap:anywhere}
.badge::before{content:"";width:6px;height:6px;border-radius:var(--r-round);background:var(--accent);flex-shrink:0}
.prose{min-width:0;line-height:1.85;overflow-wrap:anywhere}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-block:0 24px}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose a{color:var(--accent-dark)}
.prose li+li{margin-top:8px}
.reveal{transition:opacity .5s ease,transform .5s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
[data-counter]{display:inline-block;min-width:3ch;font-family:var(--font-mono);font-variant-numeric:tabular-nums;text-align:right}
#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}
#server-status>*{min-width:0;max-width:100%}
.xn-sprite{position:absolute;width:0;height:0;overflow:hidden}
.xn-notice{position:relative;z-index:30;min-height:34px;display:flex;align-items:center;justify-content:center;gap:14px;background:var(--ink);color:var(--on-ink);font-size:13px;padding:0 16px}
.xn-notice__tag{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.1em;color:var(--on-ink-muted);border:1px solid var(--ink-line);border-radius:var(--r-xs);padding:1px 6px}
.xn-notice__sep{width:1px;height:14px;background:var(--ink-line);flex-shrink:0}
.xn-notice a{display:inline-flex;align-items:center;gap:6px;min-height:28px;color:var(--on-ink);font-weight:600;text-decoration:none}
.xn-notice a svg{width:8px;height:8px;fill:currentColor}
.xn-notice a:hover{color:var(--white)}
.xn-header{position:relative;z-index:20;padding:10px 24px 0}
.xn-nav{position:relative;max-width:1200px;margin:0 auto;min-height:52px;display:flex;align-items:center;gap:4px;padding:0 8px 0 14px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:inset 0 1px 0 var(--highlight),var(--shadow-1)}
.xn-brand{display:flex;align-items:center;gap:9px;min-height:28px;padding-right:14px;margin-right:6px;border-right:1px solid var(--border-soft);color:var(--text);text-decoration:none;font-family:var(--font-display);font-weight:800;font-size:17px;letter-spacing:-.01em;white-space:nowrap}
.xn-logo{width:26px;height:26px;display:block;flex-shrink:0}
.xn-links{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.xn-links a,.xn-more__btn{display:inline-flex;align-items:center;gap:5px;min-height:34px;padding:7px 11px;border:0;border-radius:var(--r);background:none;color:var(--text);font-family:var(--font-body);font-size:14px;font-weight:500;line-height:20px;text-decoration:none;cursor:pointer;white-space:nowrap}
.xn-links a:hover,.xn-more__btn:hover{background:var(--accent-tint)}
.xn-links a[aria-current="page"],.xn-more__btn.is-current{color:var(--accent);font-weight:600}
.xn-more{position:relative}
.xn-more__btn{list-style:none}
.xn-more__btn::-webkit-details-marker{display:none}
.xn-more__btn svg{width:12px;height:12px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.xn-more__menu{position:absolute;z-index:4;top:calc(100% + 10px);left:0;min-width:188px;margin:0;padding:6px;list-style:none;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:inset 0 1px 0 var(--highlight),var(--shadow-2)}
.xn-more__menu a{display:flex;justify-content:space-between;align-items:center;width:100%;min-height:40px;padding:8px 10px;text-decoration:none;border-radius:var(--r)}
.xn-more__menu a:hover{background:var(--accent-tint)}
.xn-more__menu code{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.06em;color:var(--text-faint)}
.xn-nav__end{margin-left:auto;display:flex;align-items:center;gap:6px}
.xn-lang-wrap{position:relative}
.xn-lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;width:auto;padding:7px 10px;border:0;border-radius:var(--r);background:none;color:var(--text-muted);font-size:13.5px;text-decoration:none;cursor:pointer;white-space:nowrap;list-style:none}
.xn-lang span{white-space:nowrap}
.xn-lang::-webkit-details-marker{display:none}
.xn-lang:hover{background:var(--accent-tint)}
.xn-lang svg{width:15px;height:15px;fill:none;stroke:currentColor;stroke-width:1.5}
.xn-language-menu{left:auto;right:0}
.xn-language-menu a[aria-current="true"]{color:var(--accent);font-weight:700}
.xn-login{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;padding:0 16px;border-radius:var(--r);background:var(--ink);color:var(--on-ink);font-size:14px;font-weight:600;text-decoration:none;white-space:nowrap;box-shadow:var(--shadow-login)}
.xn-login:hover{background:var(--ink-2)}
.xn-login svg{width:14px;height:14px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.xn-hamburger{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:8px;border:0;border-radius:var(--r);background:var(--clear);color:var(--text)}
.xn-hamburger svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.8}
.xn-drawer{position:absolute;z-index:5;top:calc(100% + 8px);left:0;right:0;padding:12px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-2);max-height:calc(100dvh - 110px);overflow-y:auto;overscroll-behavior:contain}
.xn-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 12px;border-radius:var(--r);text-decoration:none}
.xn-drawer a:hover,.xn-drawer a[aria-current]{background:var(--accent-tint);color:var(--accent-dark)}
.xn-drawer__label{display:block;padding:12px;color:var(--text-muted);font-size:12px;border-top:1px solid var(--border);margin-top:8px}
.xn-veil{position:fixed;inset:0;z-index:15;border:0;background:var(--veil);cursor:pointer}
.xn-static-menu{display:none;position:relative}
.xn-static-menu>summary{min-width:44px;min-height:44px;display:flex;align-items:center;justify-content:center;cursor:pointer;list-style:none}
.xn-static-menu>summary::-webkit-details-marker{display:none}
.xn-static-menu .xn-drawer{left:auto;right:0;width:min(270px,calc(100vw - 48px))}
.site-footer{background:var(--bg-panel-2);border-top:1px solid var(--border);padding-top:56px;padding-bottom:28px}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:800;font-size:20px;text-decoration:none;min-height:32px}
.footer-brand img{width:30px;height:30px}
.footer-intro{margin-top:16px;max-width:340px;color:var(--text-muted);font-size:14px;line-height:1.8}
.footer-heading{font-family:var(--font-mono);font-size:12px;color:var(--text-muted);margin:0 0 12px;letter-spacing:.06em}
.footer-links{display:flex;flex-wrap:wrap;gap:4px 16px;list-style:none;margin:0;padding:0}
.footer-links a{display:inline-flex;align-items:center;min-height:32px;font-size:14px;text-decoration:none}
.footer-links a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px;margin-top:40px;padding-top:20px;border-top:1px solid var(--border);font-size:13px;color:var(--text-muted)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 16px}
.footer-languages a{display:inline-flex;align-items:center;min-height:28px;text-decoration:none}
.footer-languages a[aria-current]{color:var(--accent-dark);font-weight:600}
@media(min-width:901px){.xn-drawer{display:none}.xn-veil{display:none}}
@media(max-width:1000px){.xn-links a,.xn-more__btn{padding-inline:8px}.xn-brand{padding-right:10px}}
@media(max-width:900px){
  .xn-desktop{display:none}
  .xn-nav__end{margin-left:auto}
  .xn-hamburger{display:inline-flex}
  .xn-static-menu{display:block}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-grid>div:first-child{grid-column:1/-1}
}
@media(max-width:768px){
  h1{font-size:clamp(28px,5.2vw,40px)}
  :root{--section-space:48px}
  .grid--three{grid-template-columns:minmax(0,1fr)}
  .footer-grid{gap:28px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .xn-header{padding:8px 16px 0}
  .xn-nav{padding-left:10px;padding-right:4px;gap:0}
  .xn-brand{gap:6px;padding-right:0;margin-right:0;border-right:0;font-size:15px}
  .xn-logo{width:24px;height:24px}
  .xn-nav__end{gap:2px;margin-left:auto}
  .xn-lang{padding-inline:6px;font-size:12px;min-height:44px}
  .xn-login{padding-inline:11px;min-height:36px;font-size:13px}
  .xn-login svg{display:none}
  .xn-notice{gap:8px;min-height:34px;font-size:11px}
  .xn-notice__tag,.xn-notice__sep{display:none}
  .xn-notice a{font-size:11px}
  .grid--two{grid-template-columns:minmax(0,1fr)}
  .panel,.card{padding:20px}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-grid>div:first-child{grid-column:auto}
  .footer-bottom{align-items:flex-start;flex-direction:column}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}