:root {
  --bg: #ffffff;
  --bg-panel: #f6f6f9;
  --bg-panel-2: #15123a;
  --border: #e6e5ee;
  --border-soft: #efeef4;
  --border-strong: #d6d4e2;
  --accent: #5b3be0;
  --accent-dark: #3f25b8;
  --accent-top: #6c4ff0;
  --periwinkle: #7d8cf6;
  --text: #17152e;
  --text-muted: #5f5c75;
  --text-faint: #76738b;
  --success: #087d6a;
  --warn: #a46605;
  --error: #d7423a;
  --on-accent: #ffffff;
  --on-dark: #ffffff;
  --on-dark-muted: rgba(255, 255, 255, 0.76);
  --accent-wash: rgba(91, 59, 224, 0.11);
  --accent-wash-2: rgba(91, 59, 224, 0.03);
  --accent-soft: rgba(91, 59, 224, 0.06);
  --error-halo: rgba(229, 83, 75, 0.16);
  --glow-1: rgba(91, 59, 224, 0.12);
  --glow-2: rgba(125, 140, 246, 0.08);
  --glow-0: rgba(125, 140, 246, 0);
  --grad-text: linear-gradient(92deg, var(--accent) 0%, var(--periwinkle) 100%);
  --grad-accent: linear-gradient(180deg, var(--accent-top) 0%, var(--accent) 48%, var(--accent-dark) 100%);
  --grad-edge: linear-gradient(140deg, rgba(91, 59, 224, 0.55) 0%, rgba(125, 140, 246, 0.32) 34%, rgba(230, 229, 238, 0.95) 66%, rgba(125, 140, 246, 0.42) 100%);
  --grad-edge-soft: linear-gradient(120deg, rgba(91, 59, 224, 0.45) 0%, rgba(230, 229, 238, 1) 42%, rgba(230, 229, 238, 1) 100%);
  --shadow-card: 0 1px 2px rgba(23, 21, 46, 0.05), 0 10px 24px -10px rgba(23, 21, 46, 0.10), 0 48px 96px -32px rgba(63, 37, 184, 0.24);
  --shadow-front: 0 2px 4px rgba(23, 21, 46, 0.06), 0 14px 30px -12px rgba(23, 21, 46, 0.16), 0 44px 80px -28px rgba(63, 37, 184, 0.30);
  --shadow-btn: inset 0 1px 0 rgba(255, 255, 255, 0.22), 0 1px 2px rgba(23, 21, 46, 0.10), 0 10px 24px -8px rgba(63, 37, 184, 0.50);
  --shadow-soft: 0 1px 2px rgba(23, 21, 46, 0.05);
  --font-display: "Inter", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "Inter", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --r-card: 20px;
  --r-inner: 12px;
  --r-btn: 12px;
  --r-mark: 9px;
  --r-tag: 6px;
  --r-pill: 999px;
  --nav-h: 72px;
  --wrap: 1344px;
  --gutter: 48px;
  --row-h: 44px;
  --seq-w: 56px;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
html.nav-open { overflow: hidden; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font-body); font-size: 16px; line-height: 1.6; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }
img, svg { max-width: 100%; }
svg { display: block; flex-shrink: 0; }
img { display: block; }
ul, ol, dl, dd, p, h1, h2, h3, h4, figure { margin: 0; padding: 0; }
ul, ol { list-style: none; }
h1, h2, h3 { font-family: var(--font-display); font-weight: 500; line-height: 1.25; text-wrap: balance; }
h1 { font-size: clamp(34px, 3.4vw, 48px); }
h2 { font-size: clamp(26px, 2.5vw, 36px); }
h3 { font-size: clamp(20px, 2vw, 26px); }
.nowrap-term { white-space: nowrap; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: var(--r-tag); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--gutter); }
.wrap > *, .section-grid > *, .hero__grid > *, .footer-grid > * { min-width: 0; }
.section { padding-top: 96px; padding-bottom: 104px; overflow-x: clip; }
.section--panel { background: var(--bg-panel); color: var(--text); }
.section--dark, .band-dark { background: var(--bg-panel-2); color: var(--on-dark); }
.section--dark { padding-top: 96px; padding-bottom: 104px; }
.section--dark p, .band-dark__text { color: var(--on-dark-muted); }
.section-kicker { color: var(--accent-dark); font-size: 13px; font-weight: 500; letter-spacing: .05em; }
.section--dark .section-kicker { color: var(--on-dark); }
.section-title { margin-top: 16px; }
.section-intro { max-width: 48em; margin-top: 16px; color: var(--text-muted); }
.section-grid { display: grid; gap: 24px; }
.panel { min-width: 0; padding: 28px; border: 1px solid var(--border); border-radius: var(--r-card); background: var(--bg); color: var(--text); box-shadow: var(--shadow-card); }
.panel--quiet { background: var(--bg-panel); color: var(--text); box-shadow: none; }
pre { max-width: 100%; overflow-x: auto; padding: 20px; border: 1px solid var(--border); border-radius: var(--r-inner); background: var(--bg-panel); color: var(--text); font: 13px/1.7 var(--font-mono); }
pre code { white-space: pre; overflow-wrap: normal; }
code { font-family: var(--font-mono); overflow-wrap: anywhere; }
.prose { min-width: 0; max-width: 76ch; }
.prose h2, .prose h3 { margin-top: 2em; scroll-margin-top: 24px; }
.prose p, .prose ul, .prose ol, .prose pre { margin-top: 1.15em; }
.prose ul { padding-left: 1.4em; list-style: disc; }
.prose ol { padding-left: 1.4em; list-style: decimal; }
.prose a:not(.btn):not(.store-button) { color: var(--accent-dark); text-decoration: underline; text-underline-offset: .2em; }
.section--dark > .wrap > .prose a:not(.btn):not(.store-button) { color: var(--on-dark); }
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .65s ease, transform .65s ease; }
.reveal.shown { opacity: 1; transform: none; }

/* Header: the full-width tab rail has its own, wider measure. */
.topbar { position: relative; z-index: 40; background: var(--bg); color: var(--text); border-bottom: 1px solid var(--border); }
.topbar__row { display: flex; align-items: center; gap: 24px; min-height: var(--nav-h); width: 100%; max-width: min(100%, calc(1280px + var(--gutter) * 2)); margin-inline: auto; padding-inline: var(--gutter); }
.brand { display: inline-flex; align-items: center; gap: 11px; flex-shrink: 0; }
.brand__mark { width: 34px; height: 34px; flex-shrink: 0; border-radius: 50%; background: var(--bg-panel); border: 1px solid var(--border); box-shadow: var(--shadow-soft); }
.brand__name { font-family: var(--font-display); font-size: 17px; font-weight: 500; letter-spacing: -.005em; }
.tabs { margin-left: auto; min-width: 0; }
.tabs__list { display: flex; align-items: center; gap: 0; list-style: none; margin: 0; padding: 0; }
.tabs__link { position: relative; display: flex; align-items: center; height: var(--nav-h); padding-inline: 14px; font-size: 15px; color: var(--text-muted); white-space: nowrap; }
.tabs__link::after { content: ""; position: absolute; left: 14px; right: 14px; bottom: -1px; height: 2px; border-radius: var(--r-pill); background: var(--grad-text); transform: scaleX(0); transition: transform .25s ease; }
.tabs__link:hover { color: var(--text); }
.tabs__link:hover::after { transform: scaleX(.35); }
.tabs__link[aria-current="page"] { color: var(--text); font-weight: 500; }
.tabs__link[aria-current="page"]::after { transform: scaleX(1); }
.header-tools { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.language-control { position: relative; }
.lang { display: inline-flex; align-items: center; gap: 7px; min-height: 36px; padding: 0 13px 0 11px; border: 1px solid var(--border); border-radius: var(--r-pill); background: var(--bg); color: var(--text); cursor: pointer; font-size: 14px; white-space: nowrap; }
.lang svg { width: 16px; height: 16px; color: var(--text-muted); }
.lang__caret { color: var(--text-muted); font-size: 11px; }
.lang__short { display: none; }
.lang-menu { position: absolute; right: 0; top: calc(100% + 10px); z-index: 45; width: 180px; padding: 6px; border: 1px solid var(--border); border-radius: var(--r-inner); background: var(--bg); color: var(--text); box-shadow: var(--shadow-front); }
.lang-menu[hidden], .mobile-nav[hidden], .nav-veil[hidden] { display: none !important; }
.lang-menu a { display: block; padding: 10px 12px; border-radius: var(--r-tag); font-size: 14px; }
.lang-menu a:hover, .lang-menu a[aria-current="true"] { background: var(--bg-panel); color: var(--accent-dark); }
.menu-toggle { display: none; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; border: 1px solid var(--border); border-radius: var(--r-btn); background: var(--bg); color: var(--text); cursor: pointer; }
.menu-toggle svg { width: 21px; height: 21px; }
.mobile-nav { position: absolute; z-index: 42; top: 100%; left: 0; right: 0; max-height: calc(100dvh - var(--nav-h)); overflow-y: auto; overscroll-behavior: contain; padding: 12px var(--gutter) 24px; border-bottom: 1px solid var(--border); background: var(--bg); color: var(--text); box-shadow: var(--shadow-card); }
.mobile-nav ul { list-style: none; margin: 0; padding: 0; }
.mobile-nav a { display: flex; align-items: center; width: 100%; min-height: 46px; padding: 10px 14px; border-radius: var(--r-tag); }
.mobile-nav a[aria-current="page"], .mobile-nav a[aria-current="true"] { background: var(--bg-panel); color: var(--accent-dark); }
.mobile-nav__label { padding: 16px 14px 6px; border-top: 1px solid var(--border); color: var(--text-muted); font-size: 13px; }
.nav-veil { position: fixed; z-index: 30; inset: 0; background: var(--accent-wash); }

/* Approved first-screen proportions and rule-card assembly. */
.hero { position: relative; overflow-x: clip; }
.hero__grid { display: grid; grid-template-columns: minmax(0, 1fr) 740px; gap: 48px; align-items: center; min-height: 784px; padding-top: 28px; padding-bottom: 28px; }
.hero__copy { position: relative; z-index: 2; }
.badge { display: inline-flex; align-items: center; gap: 10px; max-width: 100%; padding: 6px 15px 6px 11px; border: 1px solid transparent; border-radius: var(--r-pill); background: linear-gradient(var(--bg), var(--bg)) padding-box, var(--grad-edge-soft) border-box; color: var(--text); font-size: 13px; line-height: 1.4; }
.badge__dot { width: 7px; height: 7px; flex-shrink: 0; border-radius: 50%; background: var(--error); box-shadow: 0 0 0 4px var(--error-halo); }
.badge__sep { width: 1px; height: 12px; flex-shrink: 0; background: var(--border-strong); }
.badge__muted { color: var(--text-muted); }
.hero__title { margin-top: 26px; font-size: clamp(34px, 3.4vw, 48px); font-weight: 500; line-height: 1.18; letter-spacing: -.012em; }
.hero__title-grad { background: var(--grad-text); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; color: transparent; white-space: nowrap; }
.hero__lead { margin-top: 20px; max-width: 31em; color: var(--text-muted); font-size: 17px; line-height: 1.78; }
.hero__lead strong { color: var(--text); font-weight: 500; }
.cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 52px; padding: 0 22px; border: 1px solid transparent; border-radius: var(--r-btn); font-size: 16px; font-weight: 500; line-height: 1.25; cursor: pointer; transition: transform .2s ease; }
.btn:hover { transform: translateY(-1px); }
.btn--primary { background: var(--grad-accent); color: var(--on-accent); box-shadow: var(--shadow-btn); }
.btn--primary svg { width: 18px; height: 18px; }
.btn--ghost { padding-inline: 20px; border-color: var(--border); background: var(--bg); color: var(--text); box-shadow: var(--shadow-soft); }
.btn--ghost svg { width: 16px; height: 16px; color: var(--accent); }
.devices { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 16px; max-width: 548px; margin-top: 36px; padding-top: 24px; border-top: 1px solid var(--border-soft); }
.devices__item { display: inline-flex; align-items: center; gap: 6px; color: var(--text-muted); font-size: 13px; }
.devices__item svg { width: 18px; height: 18px; color: var(--text); }
.devices__rule { width: 1px; height: 18px; background: var(--border); }
.chip { display: inline-flex; align-items: center; gap: 6px; max-width: 100%; min-height: 28px; padding: 3px 11px; border: 1px solid var(--border); border-radius: var(--r-pill); background: var(--bg-panel); color: var(--text); font-size: 12.5px; }
.chip svg { width: 12px; height: 12px; }
.devices__chips { display: inline-flex; flex-wrap: wrap; gap: 8px; }
.hero__note { margin-top: 16px; color: var(--text-faint); font-size: 12.5px; }
.stage { position: relative; isolation: isolate; width: 740px; height: 660px; }
.stage::before { content: ""; position: absolute; z-index: -1; right: -170px; bottom: -150px; width: 860px; height: 540px; background: radial-gradient(closest-side, var(--glow-1) 0%, var(--glow-2) 48%, var(--glow-0) 100%); pointer-events: none; }
.float { position: absolute; border: 1px solid transparent; border-radius: var(--r-card); background: linear-gradient(var(--bg), var(--bg)) padding-box, var(--grad-edge) border-box; color: var(--text); box-shadow: var(--shadow-card); }
.float--front { box-shadow: var(--shadow-front); }
.card-rules { left: 80px; top: 84px; z-index: 1; width: 540px; overflow: hidden; }
.card-rules__head { display: flex; align-items: center; gap: 12px; height: 52px; padding-inline: 20px; border-bottom: 1px solid var(--border-soft); }
.card-rules__tag { padding: 3px 8px; border-radius: var(--r-tag); background: var(--accent-soft); color: var(--accent-dark); font: 12.5px var(--font-mono); }
.card-rules__meta { color: var(--text-muted); font-size: 12.5px; }
.rules { position: relative; }
.rules::before { content: ""; position: absolute; top: 0; bottom: 0; left: 0; width: var(--seq-w); border-right: 1px solid var(--border); background: var(--bg-panel); }
.rules__band { position: absolute; top: calc(var(--row-h) * 5); left: 0; right: 0; height: var(--row-h); background: linear-gradient(90deg, var(--accent-wash) 0%, var(--accent-wash) 40%, var(--accent-wash-2) 100%); box-shadow: inset 2px 0 0 var(--accent); }
.rules__row { position: relative; display: flex; align-items: center; height: var(--row-h); border-top: 1px solid var(--border-soft); }
.rules__row:first-of-type { border-top: 0; }
.rules__seq { position: relative; width: var(--seq-w); flex-shrink: 0; text-align: center; color: var(--text-faint); font: 12px var(--font-mono); letter-spacing: .02em; }
.rules__seq::after { content: ""; position: absolute; right: 0; top: 50%; width: 6px; height: 1px; background: var(--border-strong); }
.rules__code { padding-left: 20px; color: var(--text); font: 13.5px/1 var(--font-mono); white-space: nowrap; }
.rules__k { font-weight: 500; }
.rules__c, .rules__cm { color: var(--text-faint); }
.rules__v { color: var(--text-muted); }
.rules__p { font-weight: 500; }
.rules__p--proxy { color: var(--accent-dark); }
.rules__p--direct { color: var(--success); }
.rules__p--reject { color: var(--error); }
.rules__cm { margin-left: 16px; }
.card-rules__foot { display: flex; justify-content: flex-end; align-items: center; height: 44px; padding-inline: 20px; border-top: 1px solid var(--border-soft); color: var(--text-muted); font-size: 12px; }
.card-store { top: 0; right: 0; z-index: 2; width: 336px; padding: 18px 18px 6px; }
.store__top { display: flex; align-items: center; gap: 12px; }
.store__icon { width: 48px; height: 48px; flex-shrink: 0; border: 1px solid var(--border); border-radius: 50%; background: var(--bg-panel); box-shadow: var(--shadow-soft); }
.store__name { font-size: 15.5px; font-weight: 500; line-height: 1.3; }
.store__src { display: flex; align-items: center; gap: 5px; margin-top: 3px; color: var(--text-muted); font-size: 12.5px; }
.store__src svg { width: 12px; height: 12px; color: var(--text); }
.store__facts { margin-top: 14px; border-top: 1px solid var(--border-soft); }
.store__fact { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; padding-block: 10px; border-bottom: 1px solid var(--border-soft); }
.store__fact:last-child { border-bottom: 0; }
.store__fact dt { color: var(--text-faint); font-size: 12px; white-space: nowrap; }
.store__fact dd { font-size: 12.5px; text-align: right; }
.store__fact dd.is-mono { font: 12.5px var(--font-mono); }
.card-route { left: 0; top: 404px; z-index: 2; width: 256px; padding: 16px 14px 14px; }
.route__label { padding: 0 6px 9px; color: var(--text-muted); font-size: 12px; font-weight: 500; letter-spacing: .02em; }
.route__group { overflow: hidden; border-radius: var(--r-inner); background: var(--bg-panel); color: var(--text); }
.route__row { position: relative; display: flex; align-items: center; justify-content: space-between; height: 42px; padding-inline: 14px 12px; font-size: 14px; }
.route__row + .route__row::before { content: ""; position: absolute; top: 0; left: 14px; right: 0; height: 1px; background: var(--border); }
.route__row svg { width: 16px; height: 16px; color: var(--text-faint); }
.route__row.is-on { font-weight: 500; }
.route__row.is-on svg { color: var(--accent-dark); }
.route__note { margin-top: 10px; padding-inline: 6px; color: var(--text-faint); font-size: 11.5px; line-height: 1.5; }
.band-dark { padding-top: 88px; padding-bottom: 96px; }
.band-dark__title { font-size: clamp(24px, 2.4vw, 34px); }
.band-dark__text { max-width: 40em; margin-top: 14px; line-height: 1.75; }

/* Footer */
.site-footer { padding-top: 72px; padding-bottom: 28px; background: var(--bg-panel-2); color: var(--on-dark); }
.footer-grid { display: grid; grid-template-columns: 1.3fr 1fr 1.35fr; gap: 48px; }
.footer-brand { display: inline-flex; align-items: center; gap: 12px; font-weight: 500; }
.footer-brand img { width: 38px; height: 38px; border-radius: 50%; }
.footer-about { max-width: 29em; margin-top: 18px; color: var(--on-dark-muted); font-size: 14px; }
.footer-heading { margin-bottom: 16px; font-size: 14px; font-weight: 500; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.footer-links a { color: var(--on-dark-muted); font-size: 14px; }
.footer-links a:hover { color: var(--on-dark); text-decoration: underline; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; margin-top: 64px; padding-top: 24px; border-top: 1px solid var(--on-dark-muted); color: var(--on-dark-muted); font-size: 13px; }

@media (max-width: 1380px) {
  .tabs__link { padding-inline: 9px; font-size: 13px; }
  .tabs__link::after { left: 9px; right: 9px; }
  .topbar__row { gap: 12px; }
}
@media (max-width: 1024px) {
  .topbar__row { min-height: var(--nav-h); }
  .tabs { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
}
@media (max-width: 1180px) {
  .hero__grid { grid-template-columns: 1fr; gap: 56px; min-height: 0; padding-top: 64px; padding-bottom: 80px; }
  .stage { margin-inline: auto; }
}
@media (max-width: 820px) {
  :root { --gutter: 20px; }
  .stage { display: flex; flex-direction: column; gap: 16px; width: 100%; height: auto; }
  .stage::before { right: -40%; bottom: -80px; width: 140%; }
  .float { position: relative; left: auto; right: auto; top: auto; width: 100%; }
  .rules { overflow-x: auto; }
  .rules__row { min-width: 530px; }
  .rules__band { min-width: 530px; }
  .card-rules__foot { justify-content: flex-start; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  h1, .hero__title { font-size: clamp(24px, 6vw, 30px); }
  .section, .section--dark { padding-top: 68px; padding-bottom: 76px; }
}
@media (max-width: 640px) {
  :root { --gutter: 18px; }
  .topbar__row { gap: 8px; }
  .brand { min-width: 0; flex-shrink: 1; }
  .brand__name { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 15px; }
  .lang__full { display: none; }
  .lang__short { display: inline; }
  .hero__grid { gap: 42px; padding-top: 48px; padding-bottom: 68px; }
  .hero__lead { font-size: 15.5px; }
  .btn { min-height: 48px; font-size: 15px; }
  .badge__muted, .badge__sep, .devices__rule { display: none; }
  .store__fact { flex-direction: column; gap: 2px; }
  .store__fact dd { text-align: left; }
  .footer-grid { grid-template-columns: 1fr; gap: 34px; }
  .tilt, [class*="tilt-"] { transform: none !important; }
}
@media (max-width: 370px) {
  .brand__name { font-size: 13px; }
  .brand__mark { width: 30px; height: 30px; }
  .lang { padding-inline: 8px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .btn, .tabs__link::after { transition: none; }
  .btn:hover { transform: none; }
}