:root {
  --bg:#E5EEFB;
  --panel:#F7FAFF;
  --groove:#D8E4F6;
  --border:#C9D6EC;
  --accent:#EC48B0;
  --accent-dark:#C02A8C;
  --text:#121733;
  --text-2:#24306A;
  --muted:#535C7D;
  --success:#12A36E;
  --warn:#D9870F;
  --error:#D63B3B;
  --white:#FFFFFF;
  --sky-top:#CFE2FA;
  --sky-mid:#DDE9FB;
  --sky-bottom:#EEF4FD;
  --wall-top:#B7D4F7;
  --wall-bottom:#E4EEFC;
  --iris-sky:#86CBFF;
  --iris-mint:#8DE6C9;
  --alu-hi:#F4F6FA;
  --alu:#CDD3DE;
  --alu-lo:#99A2B3;
  --bezel:#0E1226;
  --cam:#2B355C;
  --flag-red:#D8263C;
  --flag-blue:#22408F;
  --flag-white:#FFFFFF;
  --mask:#000000;
  --clear:transparent;
  --a-white-95:rgba(255,255,255,.95);
  --a-white-90:rgba(255,255,255,.9);
  --a-white-80:rgba(255,255,255,.8);
  --a-white-70:rgba(255,255,255,.7);
  --a-white-60:rgba(255,255,255,.6);
  --a-white-40:rgba(255,255,255,.4);
  --a-white-30:rgba(255,255,255,.3);
  --a-white-20:rgba(255,255,255,.2);
  --a-accent-14:rgba(236,72,176,.14);
  --a-accent-12:rgba(236,72,176,.12);
  --a-accent-10:rgba(236,72,176,.10);
  --a-accent-08:rgba(236,72,176,.08);
  --a-ink-20:rgba(18,23,51,.20);
  --a-ink-12:rgba(18,23,51,.12);
  --a-ink-06:rgba(18,23,51,.06);
  --a-success-14:rgba(18,163,110,.14);
  --a-success-22:rgba(18,163,110,.22);
  --a-sky-30:rgba(134,203,255,.30);
  --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","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-card:28px;
  --r-panel:20px;
  --r-win:12px;
  --r-small:9px;
  --r-pill:999px;
  --r-round:50%;
  --wrap:1240px;
  --gutter:32px;
  --header-height:64px;
  --anchor-gap:80px;
  --toc-offset:80px;
  --toc-landing:156px;
  --shadow-card:0 20px 48px var(--a-accent-10);
  --ease-out:cubic-bezier(.2,.7,.3,1);
  --speed:.2s;
}
*,*::before,*::after {box-sizing:border-box}
html {-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-gap)}
html.nav-open {overflow:hidden}
body {margin:0;font-family:var(--font-body);font-size:16px;line-height:1.7;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a {color:inherit;text-decoration:none}
a,button,summary {-webkit-tap-highlight-color:var(--a-accent-12)}
button,input,select,textarea {font:inherit;color:inherit}
button {border:0;padding:0;background:none;cursor:pointer}
button:disabled {cursor:not-allowed;opacity:.5}
img {display:block;max-width:100%;height:auto}
svg {flex-shrink:0}
ul {list-style:none;margin:0;padding:0}
p,h1,h2,h3,h4,figure {margin:0}
h1,h2,h3 {font-family:var(--font-display);text-wrap:balance;overflow-wrap:break-word}
h1 {font-size:clamp(52px,5vw,72px);line-height:1.12;font-weight:900;letter-spacing:-.02em}
h2 {font-size:clamp(28px,3.1vw,44px);line-height:1.22;font-weight:900;letter-spacing:-.02em}
h3 {font-size:22px;line-height:1.35;font-weight:800}
:focus-visible {outline:3px solid var(--accent-dark);outline-offset:3px;border-radius:var(--r-small)}
[hidden] {display:none!important}
.no-break {white-space:nowrap}
.wrap {width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter)}
.section {padding-top:88px;padding-bottom:88px}
.section-head {max-width:760px;margin:0 auto 32px;text-align:center}
.section-head p {margin-top:16px;color:var(--muted);font-size:18px}
.reading-wrap {max-width:860px;margin-inline:auto;min-width:0}
.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 {min-width:0;padding:28px;border-radius:var(--r-card);background:var(--panel);box-shadow:var(--shadow-card),inset 0 1px 0 var(--white)}
.panel-inset {background:var(--groove);box-shadow:inset 0 1px 3px var(--a-ink-06)}
.muted {color:var(--muted)}
.mono {font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.text-link {color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.sr-only {position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.prose {min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote {margin-block:20px}
.prose ul {list-style:disc;padding-left:24px}
.prose ol {padding-left:24px}
.prose li+li {margin-top:8px}
.prose h2 {margin-top:48px;margin-bottom:20px;font-size:32px}
.prose h3 {margin-top:32px;margin-bottom:16px}
.prose a {text-decoration:underline;text-underline-offset:4px;color:var(--accent-dark)}
code {font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere;word-break:break-word;background:var(--groove);border-radius:var(--r-small);padding:2px 5px}
pre {max-width:100%;overflow-x:auto;padding:24px;border-radius:var(--r-panel);background:var(--text);color:var(--panel);-webkit-overflow-scrolling:touch}
pre code {padding:0;background:none;color:inherit;white-space:pre;overflow-wrap:normal;word-break:normal}
.btn {display:inline-flex;align-items:center;justify-content:center;gap:10px;min-width:172px;min-height:52px;padding:12px 30px;border-radius:var(--r-pill);font-size:17px;font-weight:800;line-height:1.4;letter-spacing:.01em;white-space:nowrap;flex-shrink:0;transition:transform var(--speed) var(--ease-out),box-shadow var(--speed),background var(--speed)}
.btn svg {width:18px;height:18px}
.btn-ink,.btn-primary {background:var(--text);color:var(--white);box-shadow:0 14px 28px var(--a-ink-20),inset 0 1px 0 var(--a-white-20)}
.btn-ink:hover,.btn-primary:hover {background:var(--text-2);transform:translateY(-1px)}
.btn-line,.btn-secondary {background:var(--white);color:var(--text);box-shadow:inset 0 0 0 2px var(--text),0 10px 22px var(--a-accent-08)}
.btn-line:hover,.btn-secondary:hover {transform:translateY(-1px);background:var(--panel)}
.btn-small {min-width:0;min-height:40px;padding:9px 20px;font-size:14px}
.btn:active {transform:translateY(1px)}
.btn[aria-disabled="true"] {opacity:.5;pointer-events:none}
.icon-btn {display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;width:44px;height:44px;border-radius:var(--r-round);background:var(--groove)}
.icon-btn svg {width:20px;height:20px}
.cta-row {display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:14px;margin-top:22px}
.badge,.tag {display:inline-flex;align-items:center;gap:6px;max-width:100%;min-height:28px;padding:4px 12px;border-radius:var(--r-pill);font-size:13px;line-height:1.5;font-weight:700;background:var(--groove);color:var(--text-2);overflow-wrap:anywhere}
.badge-accent {background:var(--accent);color:var(--white)}
.status-dot {display:inline-block;width:8px;height:8px;flex-shrink:0;border-radius:var(--r-round);background:var(--success);box-shadow:0 0 0 3px var(--a-success-14)}
#server-status {position:static;display:block;min-width:0;min-height:120px;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+* {margin-top:32px}
.reveal {transition:opacity .35s ease,transform .35s var(--ease-out)}
.reveal.pending {opacity:0;transform:translateY(16px)}
.reveal.shown {opacity:1;transform:none}

/* Shared header */
#site-header {position:relative;z-index:100;min-height:var(--header-height)}
.topbar {position:relative;z-index:100}
.topbar-in {height:var(--header-height);display:flex;align-items:center;flex-wrap:nowrap;gap:24px}
.brand {display:inline-flex;align-items:center;gap:10px;flex-shrink:0;min-height:40px}
.brand-mark {width:30px;height:30px;flex-shrink:0}
.brand-word {font-family:var(--font-display);font-weight:900;font-size:21px;letter-spacing:-.02em;color:var(--text);white-space:nowrap}
.mainnav {flex:1;min-width:0;display:flex;justify-content:center}
.mainnav>ul {display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:4px}
.mainnav a,.more-btn {display:inline-flex;align-items:center;gap:7px;min-height:38px;padding:7px 14px;border-radius:var(--r-pill);font-size:15px;line-height:1.5;font-weight:600;color:var(--text);white-space:nowrap;transition:background var(--speed)}
.mainnav a:hover,.more-btn:hover {background:var(--a-white-60)}
.mainnav a[aria-current="page"] {background:var(--a-white-70);box-shadow:inset 0 0 0 1px var(--a-white-90)}
.mainnav>ul>li>a[aria-current="page"]::before {content:"";width:7px;height:7px;flex-shrink:0;border-radius:var(--r-round);background:radial-gradient(circle at 35% 30%,var(--accent),var(--accent-dark))}
.more {position:relative}
.more-btn svg,.lang svg {width:12px;height:12px;color:var(--muted)}
.more-menu {position:absolute;z-index:110;top:calc(100% + 10px);left:50%;width:280px;margin-left:-140px;padding:8px;border-radius:var(--r-panel);background:var(--panel);box-shadow:0 22px 48px var(--a-accent-12),0 4px 12px var(--a-ink-06),inset 0 0 0 1px var(--white);display:none}
.more.is-open>.more-menu,.more[open]>.more-menu {display:block}
.more-label {padding:6px 12px 4px;font-size:12px;font-weight:700;color:var(--muted);letter-spacing:.04em}
.more-menu a {display:flex;flex-direction:column;align-items:flex-start;gap:2px;height:auto;padding:10px 12px;border-radius:var(--r-small);white-space:normal}
.more-menu a:hover {background:var(--bg)}
.more-menu a span {font-size:14.5px;font-weight:700}
.more-menu a small {font-size:12.5px;font-weight:500;color:var(--muted)}
.topbar-end {display:flex;align-items:center;gap:14px;flex-shrink:0}
.lang-switch {position:relative}
.lang {display:inline-flex;align-items:center;justify-content:center;gap:6px;width:auto;min-width:44px;min-height:38px;padding:7px 12px;border-radius:var(--r-pill);font-size:14px;font-weight:600;color:var(--text-2);white-space:nowrap}
.lang span {white-space:nowrap}
.lang:hover {background:var(--a-white-60)}
.lang-menu {position:absolute;right:0;top:calc(100% + 10px);z-index:120;min-width:180px;padding:8px;border-radius:var(--r-panel);background:var(--panel);box-shadow:var(--shadow-card);display:none}
.lang-switch.is-open>.lang-menu,.lang-switch[open]>.lang-menu {display:block}
.lang-menu a {display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-small);font-size:14px}
.lang-menu a:hover,.lang-menu a[aria-current="true"] {background:var(--groove)}
.end-sep {width:1px;height:18px;flex-shrink:0;background:var(--border)}
.btn-login {display:inline-flex;align-items:center;justify-content:center;min-height:40px;padding:9px 22px;border-radius:var(--r-pill);background:var(--text);color:var(--white);font-size:14.5px;font-weight:700;white-space:nowrap;box-shadow:0 8px 18px var(--a-ink-20),inset 0 1px 0 var(--a-white-20);transition:background var(--speed)}
.btn-login:hover {background:var(--text-2)}
.hamburger {display:none;align-items:center;justify-content:center;flex-direction:column;gap:5px;min-width:44px;min-height:44px;border-radius:var(--r-pill);color:var(--text)}
.hamburger-line {display:block;width:20px;height:2px;background:currentColor;transition:transform var(--speed),opacity var(--speed)}
.hamburger[aria-expanded="true"] .hamburger-line:first-child {transform:translateY(7px) rotate(45deg)}
.hamburger[aria-expanded="true"] .hamburger-line:nth-child(2) {opacity:0}
.hamburger[aria-expanded="true"] .hamburger-line:last-child {transform:translateY(-7px) rotate(-45deg)}
.nav-drawer {display:none;position:fixed;z-index:110;top:var(--header-height);left:0;right:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));padding:20px var(--gutter) 40px;background:var(--panel);overflow-y:auto;overscroll-behavior:contain}
.nav-drawer a {display:flex;align-items:center;width:100%;min-height:48px;padding:12px 16px;border-radius:var(--r-win);font-weight:600}
@media (max-width:640px) {
  #site-header {position:sticky;top:0}
  .nav-drawer {padding:8px var(--gutter) 12px}
  .nav-drawer a {min-height:44px;padding:8px 16px;line-height:1.5}
  .nav-drawer .drawer-label {margin:8px 16px 4px;line-height:22px}
}
.nav-drawer a:hover,.nav-drawer a[aria-current] {background:var(--groove)}
.drawer-label {display:block;margin:24px 16px 8px;font-size:13px;font-weight:700;color:var(--muted)}
.nav-veil {display:none;position:fixed;z-index:90;inset:var(--header-height) 0 0;background:var(--a-ink-20)}
summary.more-btn,summary.lang {list-style:none;cursor:pointer}
summary.more-btn::-webkit-details-marker,summary.lang::-webkit-details-marker {display:none}

/* Shared footer */
.site-footer {padding-top:56px;padding-bottom:28px;background:var(--groove);border-top:1px solid var(--a-white-80)}
.footer-grid {display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:48px}
.footer-brand {min-width:0}
.footer-brand p {max-width:340px;margin-top:16px;color:var(--muted)}
.footer-title {font-size:14px;font-weight:800;margin-bottom:12px}
.footer-links {display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 16px}
.footer-links a {display:inline-flex;align-items:center;min-height:32px;font-size:14px;overflow-wrap:anywhere}
.footer-links a:hover,.footer-bottom a:hover {color:var(--accent-dark);text-decoration:underline}
.footer-languages {display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:32px}
.footer-languages a {display:inline-flex;align-items:center;min-height:32px;font-size:14px}
.footer-languages a[aria-current="true"] {color:var(--accent-dark);font-weight:700}
.footer-bottom {display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px 24px;margin-top:24px;padding-top:24px;border-top:1px solid var(--border);font-size:13px;color:var(--muted)}
.footer-legal {display:flex;flex-wrap:wrap;gap:8px 20px}
.footer-legal a {display:inline-flex;align-items:center;min-height:28px}
@media (max-width:1100px) {
  .topbar-in {gap:14px}
  .mainnav a,.more-btn {padding-inline:10px;font-size:14px}
  .topbar-end {gap:8px}
}
@media (max-width:960px) {
  .mainnav {display:none}
  .topbar-end {margin-left:auto}
  .hamburger {display:flex}
  .nav-drawer.is-open,.nav-veil.is-open {display:block}
  .footer-grid {gap:32px;grid-template-columns:1fr 1fr}
  .footer-brand {grid-column:1/-1}
  .grid-five {grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media (max-width:768px) {
  h1 {font-size:clamp(28px,7vw,40px);line-height:1.12}
  .section {padding-top:56px;padding-bottom:56px}
  .grid-three {grid-template-columns:minmax(0,1fr)}
}
@media (max-width:640px) {
  :root {--gutter:16px}
  .no-break {white-space:normal}
  .tilt {transform:none!important}
  .topbar-in {gap:8px}
  .brand {gap:6px}
  .brand-mark {width:26px;height:26px}
  .brand-word {font-size:18px}
  .topbar-end {gap:4px;margin-left:auto}
  .lang {padding-inline:7px;font-size:12px}
  .lang svg {display:none}
  .end-sep {display:none}
  .btn-login {padding-inline:14px;font-size:13px}
  .footer-grid {grid-template-columns:minmax(0,1fr);gap:28px}
  .footer-brand {grid-column:auto}
  .footer-bottom {align-items:flex-start;flex-direction:column}
  .grid-five {grid-template-columns:repeat(2,minmax(0,1fr))}
  .panel,.card {padding:24px}
  .prose h2 {font-size:27px}
}
@media (max-width:360px) {
  .brand-word {font-size:16px}
  .brand-mark {width:23px;height:23px}
  .lang {font-size:11px;padding-inline:4px}
  .btn-login {padding-inline:11px}
}
@media (prefers-reduced-motion:reduce) {
  html {scroll-behavior:auto}
  *,*::before,*::after {animation:none!important;transition:none!important}
  .reveal,.reveal.pending {opacity:1;transform:none}
}