:root{
  color-scheme:light;
  --bg:#F8EFE1;
  --panel:#FFFBF4;
  --panel-2:#F0E5D3;
  --line:#E2D4BE;
  --accent:#3238E6;
  --accent-dark:#2126B8;
  --text:#2A2017;
  --muted:#6E6152;
  --success:#2F8F5B;
  --warn:#C98A1A;
  --error:#C8402F;
  --coral:#F2897C;
  --ink:#241B14;
  --hi:#FFFFFF;
  --flag-red:#D7262E;
  --flag-white:#FFFFFF;
  --flag-blue:#28348A;
  --flag-black:#1F1B18;
  --flag-gold:#F2C230;
  --f-display:"Iowan Old Style","Palatino Linotype",Georgia,"Songti SC","STSong","Noto Serif CJK SC","Source Han Serif SC",serif;
  --f-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-xs:6px;
  --r-s:8px;
  --r-m:10px;
  --r-l:12px;
  --r-pill:999px;
  --r-circle:50%;
  --r-logo:9px;
  --r-mini:5px;
  --r-tab:7px;
  --r-bubble:18px;
  --r-strip:3px;
  --gutter:32px;
  --content-width:1264px;
  --header-height:64px;
  --anchor-offset:88px;
  --toc-offset:144px;
  --size-body:16px;
  --size-small:14px;
  --size-micro:12px;
  --size-h1:clamp(52px,4.5vw,66px);
  --size-h2:clamp(28px,3vw,40px);
  --size-h3:22px;
  --tint:color-mix(in srgb,var(--accent) 11%,transparent);
  --lift:0 1px 2px color-mix(in srgb,var(--accent) 8%,transparent),0 18px 36px -16px color-mix(in srgb,var(--accent) 24%,transparent);
  --lift-xl:0 2px 6px color-mix(in srgb,var(--accent) 6%,transparent),0 30px 60px -28px color-mix(in srgb,var(--accent) 22%,transparent),0 60px 120px -40px color-mix(in srgb,var(--accent) 12%,transparent);
  --grain:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3CfeComponentTransfer%3E%3CfeFuncR type='linear' slope='2.4' intercept='-.7'/%3E%3CfeFuncG type='linear' slope='2.4' intercept='-.7'/%3E%3CfeFuncB type='linear' slope='2.4' intercept='-.7'/%3E%3CfeFuncA type='linear' slope='0' intercept='1'/%3E%3C/feComponentTransfer%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)'/%3E%3C/svg%3E");
  --edge-down:radial-gradient(circle at 8px 2px,var(--ink) 6.5px,transparent 7px) left bottom/16px 10px repeat-x,linear-gradient(var(--ink),var(--ink)) left top/100% calc(100% - 9px) no-repeat;
  --edge-up:radial-gradient(circle at 8px 8px,var(--ink) 6.5px,transparent 7px) left top/16px 10px repeat-x,linear-gradient(var(--ink),var(--ink)) left 9px/100% calc(100% - 9px) no-repeat;
}
*,*::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(--f-body);font-size:var(--size-body);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:clip}
a{color:var(--accent-dark);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:4px}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,a,summary,input,select,textarea{-webkit-tap-highlight-color:transparent}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:var(--r-xs)}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
[hidden]{display:none!important}
h1,h2,h3{font-weight:700;line-height:1.2;text-wrap:balance;overflow-wrap:break-word}
h1,.h1{font-family:var(--f-display);font-size:var(--size-h1);line-height:1.12;letter-spacing:-.02em}
h2{font-size:var(--size-h2)}
h3{font-size:var(--size-h3)}
p{margin:0 0 1em}
ul,ol{padding-left:1.4em}
li+li{margin-top:.3em}
code{font-family:var(--f-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--panel-2);border:1px solid var(--line);border-radius:var(--r-s);font-family:var(--f-mono);font-size:var(--size-small)}
pre code{overflow-wrap:normal;white-space:pre}
.wrap{width:100%;max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:80px;padding-bottom:80px}
.section-head{max-width:800px;margin-bottom:32px}
.section-head h2{margin:0 0 16px}
.section-head p{color:var(--muted)}
.reading-wrap{max-width:880px;margin-inline:auto}
.prose{overflow-wrap:break-word}
.prose p,.prose li{line-height:1.85}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose a{text-decoration:underline}
.no-break{white-space:nowrap}
.muted{color:var(--muted)}
.mono{font-family:var(--f-mono)}
.panel,.card{min-width:0;padding:24px;border:1px solid var(--line);border-radius:var(--r-l);background:var(--panel);box-shadow:inset 0 1px 0 var(--hi),var(--lift)}
.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
:where(.card-grid,.win-body,.feature-layout,.footer-grid)>*{min-width:0}
.btn,.btn-main,.btn-primary,.btn-ghost,.btn-secondary{display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;max-width:100%;white-space:nowrap;min-height:44px;border:0;font-family:var(--f-body);font-weight:600;text-decoration:none;transition:transform .2s ease,background-color .2s ease,box-shadow .2s ease}
.btn:hover,.btn-main:hover,.btn-primary:hover,.btn-ghost:hover,.btn-secondary:hover{text-decoration:none}
.btn-main,.btn-primary{gap:14px;height:58px;padding:6px 22px 6px 6px;border-radius:var(--r-pill);background:var(--ink);color:var(--panel);font-size:17px;letter-spacing:.02em;box-shadow:inset 0 1px 0 color-mix(in srgb,var(--hi) 12%,transparent),0 16px 30px -14px color-mix(in srgb,var(--ink) 60%,transparent),0 30px 50px -30px color-mix(in srgb,var(--accent) 30%,transparent)}
.btn-main:hover,.btn-primary:hover{transform:translateY(-1px)}
.btn-chip{flex:none;width:46px;height:46px;border-radius:var(--r-l);display:grid;place-items:center;background:var(--bg);color:var(--accent);--hx-face:var(--hi);box-shadow:inset 0 0 0 1px var(--hi),inset 0 -2px 0 color-mix(in srgb,var(--line) 70%,transparent)}
.btn-chip svg{display:block;width:28px;height:28px}
.btn-arrow{display:block;width:20px;height:20px;color:color-mix(in srgb,var(--panel) 72%,transparent)}
.btn-ghost,.btn-secondary{height:58px;padding:0 28px;border-radius:var(--r-pill);font-size:var(--size-body);color:var(--text);background:color-mix(in srgb,var(--panel) 55%,transparent);box-shadow:inset 0 0 0 1.5px color-mix(in srgb,var(--text) 22%,transparent)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--panel);box-shadow:inset 0 0 0 1.5px color-mix(in srgb,var(--text) 40%,transparent)}
.btn{padding:10px 20px;border-radius:var(--r-s);background:var(--ink);color:var(--panel);font-size:var(--size-small)}
.btn:disabled,.btn-main:disabled{cursor:not-allowed;background:var(--panel-2);color:var(--muted);box-shadow:none}
.cta-row{margin-top:24px;display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:14px}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.hx-face{fill:var(--hx-face,none);stroke:currentColor;stroke-width:1.7;stroke-linejoin:round}
.hx-spoke{fill:none;stroke:currentColor;stroke-width:1.3;stroke-linecap:round;opacity:.75}
.hx-node{fill:currentColor}
.fl-r{fill:var(--flag-red)}
.fl-w{fill:var(--flag-white)}
.fl-b{fill:var(--flag-blue)}
.fl-k{fill:var(--flag-black)}
.fl-g{fill:var(--flag-gold)}
.fl-edge{fill:none;stroke:color-mix(in srgb,var(--ink) 16%,transparent);stroke-width:1}
.flag{flex:none;display:block;width:21px;height:14px;overflow:hidden;border-radius:var(--r-strip)}
.grain{position:relative;isolation:isolate}
.grain::before{content:"";position:absolute;inset:0;z-index:-1;background-image:var(--grain);background-size:220px 220px;opacity:.08;pointer-events:none}
#site-header{position:relative;z-index:60}
.topband{position:relative;z-index:50;background:var(--accent);color:var(--panel)}
.topband::after{content:"";position:absolute;top:100%;left:0;right:0;height:10px;background:var(--accent);-webkit-mask:var(--edge-down);mask:var(--edge-down);pointer-events:none}
.nav{display:flex;align-items:center;flex-wrap:nowrap;gap:40px;height:var(--header-height)}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none;color:var(--text);text-decoration:none}
.brand:hover{text-decoration:none}
.brand-logo{width:32px;height:32px;flex:none;border-radius:var(--r-logo)}
.brand-en{font-weight:700;font-size:18px;letter-spacing:-.01em;color:inherit}
.brand-zh{font-size:var(--size-small);font-weight:400;color:var(--muted)}
.topband .brand{color:var(--hi)}
.desktop-nav{flex:1;min-width:0}
.nav-links{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:26px;font-size:14.5px;font-weight:500}
.nav-links li{margin:0}
.nav-links a{display:inline-flex;align-items:center;min-height:32px;white-space:nowrap;padding:6px 0;color:color-mix(in srgb,var(--panel) 85%,transparent)}
.nav-links a:hover,.nav-links a[aria-current="page"]{color:var(--hi);text-decoration:none}
.nav-links a[aria-current="page"]{font-weight:700}
.topband :where(a,button):focus-visible{outline-color:var(--panel)}
.nav-tail{margin-left:auto;display:flex;align-items:center;gap:12px;flex-shrink:0}
.language{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:5px;min-height:36px;min-width:44px;width:auto;font-family:var(--f-body);font-size:var(--size-small);color:var(--panel);background:none;border:0;padding:6px 8px;border-radius:var(--r-xs);cursor:pointer;white-space:nowrap}
.lang:hover{background:color-mix(in srgb,var(--hi) 10%,transparent)}
.lang-panel{position:absolute;right:0;top:calc(100% + 12px);z-index:90;min-width:180px;padding:8px;background:var(--panel);color:var(--text);border:1px solid var(--line);border-radius:var(--r-s);box-shadow:var(--lift)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;color:var(--text);border-radius:var(--r-xs)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--tint);color:var(--accent-dark);text-decoration:none}
.login{display:inline-flex;align-items:center;justify-content:center;height:36px;min-height:36px;padding:0 18px;border-radius:var(--r-s);background:var(--panel);color:var(--accent-dark);font-size:var(--size-small);font-weight:700;white-space:nowrap;box-shadow:inset 0 -1px 0 color-mix(in srgb,var(--accent) 14%,transparent),0 6px 14px -8px color-mix(in srgb,var(--ink) 50%,transparent)}
.login:hover{text-decoration:none;background:var(--bg)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:5px;min-width:44px;min-height:44px;padding:10px;border:1px solid color-mix(in srgb,var(--panel) 40%,transparent);border-radius:var(--r-s);color:var(--panel);background:transparent}
.menu-line{display:block;width:20px;height:2px;background:currentColor;border-radius:var(--r-pill)}
.menu-toggle[aria-expanded="true"] .menu-line:first-child{transform:translateY(7px) rotate(45deg)}
.menu-toggle[aria-expanded="true"] .menu-line:nth-child(2){visibility:hidden}
.menu-toggle[aria-expanded="true"] .menu-line:last-child{transform:translateY(-7px) rotate(-45deg)}
.mobile-drawer{position:fixed;z-index:45;top:var(--header-height);left:0;right:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:24px var(--gutter);border-top:1px solid var(--line)}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;color:var(--text);border-radius:var(--r-s)}
.mobile-drawer a[aria-current]{color:var(--accent-dark);background:var(--tint)}
.mobile-drawer a:hover{background:var(--panel-2);text-decoration:none}
.drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--line)}
.menu-veil{position:fixed;z-index:40;top:var(--header-height);inset-inline:0;bottom:0;background:color-mix(in srgb,var(--ink) 30%,transparent);border:0}
.site-footer{padding-top:64px;padding-bottom:28px;border-top:1px solid var(--line);background:var(--panel-2)}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:48px}
.footer-brand p{margin-top:20px;max-width:340px;color:var(--muted);font-size:var(--size-small)}
.footer-heading{margin:0 0 16px;font-size:var(--size-body);font-weight:700}
.footer-links{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:var(--size-small);color:var(--text)}
.footer-languages{display:flex;flex-wrap:wrap;gap:12px 24px;margin-top:32px;padding-top:24px;border-top:1px solid var(--line)}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;margin-top:24px;color:var(--muted);font-size:var(--size-small)}
.footer-bottom p{margin:0}
.footer-legal{display:flex;gap:24px}
.reveal{transition:opacity .35s ease,transform .35s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:120px;min-width:0;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+*{margin-top:24px}
[data-counter]{display:inline-block;font-variant-numeric:tabular-nums;min-width:3ch;text-align:right;font-family:var(--f-mono)}
@media(min-width:1101px) and (max-width:1360px){
  .nav{gap:22px}
  .nav-links{gap:18px;font-size:var(--size-small)}
  .nav-tail{gap:6px}
}
@media(max-width:1100px){
  .desktop-nav{display:none}
  .menu-toggle{display:flex}
  .nav-tail{margin-left:auto}
  .nav{gap:16px}
}
@media(min-width:1101px){
  .mobile-drawer,.menu-veil{display:none!important}
}
@media(max-width:768px){
  :root{--gutter:24px;--size-h1:clamp(28px,5.2vw,40px);--size-h2:30px}
  .section{padding-top:56px;padding-bottom:56px}
  .card-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .footer-brand{grid-column:1/-1}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,.f-refund,.f-note{transform:none}
  .nav{gap:8px}
  .nav-tail{margin-left:auto;gap:4px}
  .brand{gap:7px}
  .brand-en{font-size:var(--size-body)}
  .brand-logo{width:28px;height:28px}
  .login{padding-inline:12px}
  .lang{padding-inline:5px;font-size:var(--size-micro)}
  .footer-grid{grid-template-columns:1fr}
  .footer-brand{grid-column:auto}
  .panel,.card{padding:20px}
  .section-head{margin-bottom:24px}
  .cta-row{gap:10px}
  .btn-ghost,.btn-secondary{padding-inline:20px}
  .decoration{max-width:100%;overflow-x:clip}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation-duration:0s!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}