:root{
  color-scheme:light;
  --bg:#F9F2E4;--bg-panel:#FFFCF6;--bg-panel2:#F1E7D4;--border:#E5D8C0;
  --accent:#1D4E89;--accent-dark:#143A68;--accent-bright:#2C8FD8;
  --text:#2A2117;--text-muted:#6E604E;--success:#2E8A57;--warn:#F2C84B;--error:#C2412D;--white:#FFFFFF;
  --hero-top:#FCF8F0;--hero-bottom:#F4EBDB;--deck-from:#E4EEF7;--deck-to:#F3F1EA;
  --candy-coral:#DE8A78;--candy-plum:#9C7BB5;--candy-teal:#4FA69F;--candy-yellow:#D9AC49;--candy-sky:#6EA2D2;
  --flag-red:#D7342B;--flag-navy:#2A3C7A;--flag-blue:#2849A0;--flag-white:#FFFFFF;
  --clear:transparent;--veil:rgb(42 33 23 / .3);--highlight:rgb(255 255 255 / .95);
  --shadow-deck:0 44px 90px -36px rgb(29 78 137 / .22),0 20px 56px rgb(29 78 137 / .12),inset 0 1px 0 rgb(255 255 255 / .95),inset 0 0 0 1px rgb(255 255 255 / .55);
  --shadow-card:0 16px 32px -14px rgb(29 78 137 / .26),0 3px 8px rgb(29 78 137 / .07),inset 0 1px 0 rgb(255 255 255 / .95),inset 0 0 0 1px rgb(255 255 255 / .7);
  --shadow-chip:0 8px 20px -10px rgb(29 78 137 / .24),inset 0 1px 0 rgb(255 255 255 / .9);
  --shadow-tile:0 0 0 7px rgb(255 255 255 / .78),0 0 0 8px rgb(29 78 137 / .10),0 22px 40px -12px rgb(20 58 104 / .48),inset 0 1px 0 rgb(255 255 255 / .45),inset 0 -8px 14px rgb(20 58 104 / .35);
  --shadow-cta:0 14px 28px -12px rgb(29 78 137 / .55),inset 0 1px 0 rgb(255 255 255 / .35);
  --shadow-notice:inset 0 1px 0 rgb(255 255 255 / .45);
  --shadow-notice-btn:0 4px 10px -4px rgb(42 33 23 / .25);
  --sheen:linear-gradient(135deg,rgb(255 255 255 / .55) 0%,rgb(255 255 255 / .14) 36%,rgb(255 255 255 / 0) 38%);
  --deck-glow:radial-gradient(ellipse 34% 52% at 50% 48%,rgb(255 255 255 / .75) 0%,rgb(255 255 255 / 0) 72%);
  --paper-noise:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)'/%3E%3C/svg%3E");
  --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","Hiragino Sans","Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-pill:999px;--r-deck:32px;--r-card:18px;--r-tile:26px;--r-note:16px;--r-small:4px;--r-round:50%;
  --gutter:24px;--content-width:1248px;--reading-width:820px;
  --header-height:64px;--anchor-offset:80px;--toc-offset:144px;
  --text-xs:13px;--text-sm:14px;--text-base:16px;--text-lg:20px;
  --h1:64px;--h2:36px;--h3:24px;
  --weight-normal:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-heavy:800;
  --ease-fast:.2s;--ease-reveal:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--text-base);line-height:1.6;-webkit-font-smoothing:antialiased}
body::before{content:"";position:fixed;inset:0;z-index:60;pointer-events:none;background:var(--text);opacity:.065;-webkit-mask-image:var(--paper-noise);mask-image:var(--paper-noise)}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit}
button{cursor:pointer;color:inherit}
button:disabled{cursor:not-allowed}
a,button,summary{ -webkit-tap-highlight-color:var(--clear)}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:4px}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
ul{list-style:none;margin:0;padding:0}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-heavy);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:var(--h1);line-height:1.1;letter-spacing:-.02em}
h2{font-size:var(--h2);line-height:1.2;letter-spacing:-.02em}
h3{font-size:var(--h3);line-height:1.35}
p{margin:0 0 1.25em}
:where(main,section,article,nav,div,li){min-width:0}
.wrap{width:100%;max-width:var(--content-width);padding-inline:var(--gutter);margin-inline:auto}
.reading-wrap{width:100%;max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:64px;padding-bottom:64px}
.section-heading{margin:0 0 24px}
.muted{color:var(--text-muted)}
.no-break{white-space:nowrap}
.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}
.skip-link{position:absolute;left:var(--gutter);top:-100px;z-index:100;background:var(--bg-panel);padding:12px 20px;border-radius:var(--r-pill)}
.skip-link:focus{top:8px}
code{font-family:var(--font-mono);overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--bg-panel2);border-radius:var(--r-note)}
pre code{overflow-wrap:normal;white-space:pre}
.prose{overflow-wrap:break-word}
.prose p,.prose li{line-height:1.85}
.prose a{text-decoration:underline;text-underline-offset:4px;color:var(--accent)}
.prose ul{list-style:disc;padding-left:1.4em}
.prose ol{padding-left:1.6em}
.prose h2{margin-top:1.8em}
.prose h3{margin-top:1.5em}
.prose section[id]{scroll-margin-top:var(--anchor-offset)}
.panel,.card{background:var(--bg-panel);border-radius:var(--r-card);box-shadow:var(--shadow-card);padding:28px}
.panel-inset{background:var(--bg-panel2);border-radius:var(--r-note);padding:24px}
.grid-three{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid-five{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:16px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:52px;padding:0 32px;border:0;border-radius:var(--r-pill);font-size:17px;font-weight:var(--weight-bold);letter-spacing:.01em;line-height:1.3;flex-shrink:0;white-space:nowrap;transition:transform var(--ease-fast),box-shadow var(--ease-fast),background var(--ease-fast)}
.btn svg{width:18px;height:18px}
.btn-go,.btn-primary{background:linear-gradient(115deg,var(--accent-bright),var(--accent));color:var(--white);box-shadow:var(--shadow-cta)}
.btn-go:hover,.btn-primary:hover{transform:translateY(-1px)}
.btn-line,.btn-secondary{border:1.5px solid var(--accent);color:var(--accent);background:color-mix(in srgb,var(--bg-panel) 70%,var(--clear))}
.btn-line:hover,.btn-secondary:hover{background:var(--bg-panel)}
.btn:active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.55;box-shadow:none;pointer-events:none}
.btn-small{height:40px;padding-inline:20px;font-size:var(--text-sm)}
.cta-row{margin-top:20px;display:flex;justify-content:center;gap:14px;flex-wrap:wrap}
#site-header{position:relative;z-index:90;min-height:var(--header-height)}
.masthead{height:var(--header-height);display:flex;align-items:center;gap:28px;border-bottom:1px solid color-mix(in srgb,var(--border) 70%,var(--clear));background:var(--hero-top);position:relative;z-index:93}
.masthead .wrap{display:flex;align-items:center;gap:28px;height:100%;flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:var(--weight-heavy);font-size:20px;letter-spacing:-.02em;color:var(--text);flex-shrink:0;min-height:44px}
.brand-mark{width:34px;height:34px}
.brand-word{white-space:nowrap}
.brand-word b{color:var(--accent)}
.brand-zh{font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--text-muted)}
.mainnav{margin-left:auto;flex:1;min-width:0}
.mainnav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:26px;justify-content:flex-end}
.mainnav li{flex-shrink:0}
.mainnav a{display:inline-flex;align-items:center;min-height:40px;font-size:15px;font-weight:var(--weight-medium);color:var(--text-muted);letter-spacing:.005em;white-space:nowrap;transition:color var(--ease-fast)}
.mainnav a:hover{color:var(--text)}
.mainnav a[aria-current="page"]{font-weight:var(--weight-heavy);color:var(--text)}
.header-tools{display:flex;align-items:center;gap:16px;flex-shrink:0}
.lang-control{position:relative}
.lang-pick{display:inline-flex;align-items:center;justify-content:center;gap:6px;font-size:var(--text-sm);font-weight:var(--weight-semibold);color:var(--text-muted);padding:6px 4px;background:var(--clear);border:0;min-height:40px;min-width:44px;width:auto}
.lang-pick span{white-space:nowrap}
.lang-pick svg{width:16px;height:16px}
.lang-panel{position:absolute;right:0;top:calc(100% + 8px);z-index:96;width:180px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-note);box-shadow:var(--shadow-card)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-small);font-size:var(--text-sm)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--bg-panel2);color:var(--accent)}
.signin{display:inline-flex;align-items:center;justify-content:center;height:40px;padding:0 22px;border-radius:var(--r-pill);background:var(--accent);color:var(--white);font-size:15px;font-weight:var(--weight-bold);box-shadow:var(--shadow-chip);white-space:nowrap;transition:background var(--ease-fast)}
.signin:hover{background:var(--accent-dark)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;background:var(--clear);border:1px solid var(--border);border-radius:var(--r-pill)}
.menu-line{display:block;width:20px;height:2px;background:currentColor}
.mobile-drawer{position:fixed;top:var(--header-height);right:0;width:min(420px,100%);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) 40px;z-index:92}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;border-radius:var(--r-note)}
.mobile-drawer a[aria-current="page"],.mobile-drawer a[aria-current="true"]{background:var(--bg-panel2);color:var(--accent);font-weight:var(--weight-bold)}
.drawer-languages{margin-top:16px;padding-top:16px;border-top:1px solid var(--border)}
.nav-veil{position:fixed;inset:var(--header-height) 0 0;background:var(--veil);border:0;z-index:91}
html.nav-open{overflow:hidden}
.site-footer{padding-top:56px;padding-bottom:24px;background:var(--bg-panel2);margin-top:48px}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:40px}
.footer-intro{max-width:350px;color:var(--text-muted);margin-top:16px}
.footer-title{font-size:var(--text-base);font-weight:var(--weight-heavy);margin:0 0 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;font-size:var(--text-sm)}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{text-decoration:underline;color:var(--accent)}
.footer-languages{display:flex;gap:8px 24px;flex-wrap:wrap;margin-top:32px;padding-top:20px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;gap:16px;flex-wrap:wrap;margin-top:16px;color:var(--text-muted);font-size:var(--text-xs)}
.footer-bottom p{margin:0}
.footer-legal{display:flex;gap:20px;flex-wrap:wrap}
.reveal{transition:opacity var(--ease-reveal) ease,transform var(--ease-reveal) ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:static;display:block;min-height:160px;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+*{margin-top:32px}
@media(min-width:981px){.mobile-drawer,.nav-veil{display:none}}
@media(max-width:1280px){.masthead .wrap{gap:20px}.mainnav ul{gap:18px}.mainnav a{font-size:var(--text-sm)}.header-tools{gap:12px}}
@media(max-width:1120px){.masthead .wrap{gap:14px}.mainnav ul{gap:12px}.lang-pick{font-size:var(--text-xs)}.signin{padding-inline:18px}}
@media(max-width:980px){.mainnav{display:none}.menu-toggle{display:inline-flex}.header-tools{margin-left:auto}.masthead .wrap{justify-content:space-between}.grid-five{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:768px){:root{--h1:36px;--h2:28px;--h3:22px}.grid-three{grid-template-columns:minmax(0,1fr)}.grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}.section{padding-top:40px;padding-bottom:40px}.footer-grid{grid-template-columns:minmax(0,1fr);gap:28px}.btn{height:48px;padding-inline:26px;font-size:var(--text-base)}}
@media(max-width:640px){:root{--gutter:16px}.no-break{white-space:normal}.tilt,.float-note,.float-tag{transform:none}.lang-pick span{display:none}.header-tools{gap:6px;margin-left:auto}.masthead .wrap{gap:8px}.brand{font-size:18px;gap:6px}.brand-mark{width:30px;height:30px}.signin{padding-inline:14px;font-size:var(--text-sm)}.panel,.card{padding:22px}.footer-links{gap:6px 16px}.decoration,.stripe-halo{max-width:100%}}
@media(max-width:350px){.brand{font-size:var(--text-base)}.brand-mark{width:26px;height:26px}.signin{padding-inline:12px}.header-tools{gap:3px}.grid-five{grid-template-columns:minmax(0,1fr)}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.reveal,.reveal.pending{opacity:1;transform:none;transition:none}*,*::before,*::after{animation-duration:0s!important;animation-iteration-count:1!important;transition-duration:0s!important}}