@font-face { font-family: "Inter Var"; src: url("/assets/fonts/inter-var-latin.woff2") format("woff2"); font-weight: 100 900; font-style: normal; font-display: swap; unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "JetBrains Mono"; src: url("/assets/fonts/jetbrains-mono-latin.woff2") format("woff2"); font-weight: 100 800; font-style: normal; font-display: swap; unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }

:root {
  color-scheme: dark;
  --bg-0: #07090c;
  --bg-1: #0b0e13;
  --bg-2: #11151c;
  --bg-3: #171c25;
  --line: rgba(255, 255, 255, 0.07);
  --line-strong: rgba(255, 255, 255, 0.13);
  --text-1: #f4f6f9;
  --text-2: #a3abb8;
  --text-3: #6b7482;
  --brand-1: #26dcec;
  --brand-2: #0c73fe;
  --brand-grad: linear-gradient(135deg, var(--brand-1), var(--brand-2));
  --brand-glow: rgba(38, 220, 236, 0.18);
  --ok: #3ddc97;
  --warn: #f5b84c;
  --danger: #ff6b6b;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --button-radius: 10px;
  --shadow-card: inset 0 1px 0 rgba(255, 255, 255, 0.04), 0 24px 60px -24px rgba(0, 0, 0, 0.7);
  --shadow-glow: 0 0 0 1px rgba(38, 220, 236, 0.25), 0 20px 80px -20px var(--brand-glow);
  --section-y: clamp(88px, 11vw, 144px);
  --max-width: 1200px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --header-h: 64px;
  --font-sans: "Inter Var", "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Consolas, monospace;
  font-family: var(--font-sans);
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; background: var(--bg-0); }
body { min-width: 320px; margin: 0; overflow-x: hidden; color: var(--text-2); background: var(--bg-0); font-size: 16px; line-height: 1.7; }
body.menu-open { overflow: hidden; }
a, button, summary { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }
button { font: inherit; }
img, picture { display: block; max-width: 100%; }
h1, h2, h3, p { overflow-wrap: anywhere; }
h1, h2, h3 { text-wrap: balance; }
:focus-visible { outline: 2px solid var(--brand-1); outline-offset: 3px; }
::selection { color: var(--bg-0); background: var(--brand-1); }

.skip-link { position: fixed; top: 12px; left: 12px; z-index: 100; padding: 10px 14px; border-radius: var(--radius-sm); color: var(--bg-0); background: var(--text-1); text-decoration: none; transform: translateY(-200%); }
.skip-link:focus { transform: translateY(0); }
.section-shell { width: min(calc(100% - 48px), var(--max-width)); margin: 0 auto; }

/* Typography */
.display { margin: 0; color: var(--text-1); font-size: clamp(32px, 6.2vw, 88px); font-weight: 700; line-height: 1.05; letter-spacing: -0.02em; }
.h2, .section-head h2 { margin: 0; color: var(--text-1); font-size: clamp(32px, 3.6vw, 52px); font-weight: 650; line-height: 1.15; letter-spacing: -0.01em; }
.lead { margin: 0; color: var(--text-2); font-size: clamp(17px, 1.6vw, 20px); line-height: 1.6; }
.eyebrow { margin: 0 0 14px; color: var(--brand-1); font-family: var(--font-mono); font-size: 12px; font-weight: 500; letter-spacing: 0.12em; text-transform: uppercase; }
.caption { color: var(--text-3); font-size: 13px; }
.section { padding: var(--section-y) 0; }
.section-alt { background: var(--bg-1); }
.section-head { max-width: 760px; margin-bottom: clamp(40px, 5vw, 64px); }
.section-head .lead { margin-top: 18px; }
.section-head.is-centered { margin-right: auto; margin-left: auto; text-align: center; }
code, kbd { font-family: var(--font-mono); }
.tabular { font-variant-numeric: tabular-nums; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 50; border-bottom: 1px solid var(--line); color: var(--text-1); background: rgba(7, 9, 12, 0.72); backdrop-filter: blur(18px) saturate(140%); }
.nav-shell { display: flex; width: min(calc(100% - 48px), var(--max-width)); height: var(--header-h); margin: 0 auto; align-items: center; justify-content: space-between; gap: 32px; }
.brand { display: inline-flex; min-height: 44px; align-items: center; gap: 10px; color: var(--text-1); font-size: 18px; font-weight: 650; letter-spacing: -0.02em; text-decoration: none; }
.brand img { width: 34px; height: 34px; object-fit: contain; }
.desktop-nav { display: flex; align-items: center; gap: 6px; }
.desktop-nav a, .text-link { display: inline-flex; min-height: 40px; padding: 0 12px; border-radius: var(--radius-sm); align-items: center; color: var(--text-2); font-size: 14px; font-weight: 500; text-decoration: none; transition: color 160ms ease, background 160ms ease; }
.desktop-nav a:hover, .text-link:hover { color: var(--text-1); background: rgba(255, 255, 255, 0.05); }
.desktop-nav a.is-current, .desktop-nav a[aria-current="page"] { color: var(--text-1); }
.nav-actions { display: flex; align-items: center; gap: 8px; }

.menu-button { display: none; width: 44px; height: 44px; padding: 0; border: 1px solid var(--line-strong); border-radius: var(--button-radius); align-items: center; justify-content: center; flex-direction: column; gap: 5px; color: var(--text-1); background: transparent; cursor: pointer; }
.menu-button span { width: 18px; height: 1.5px; background: currentColor; transition: transform 180ms ease, opacity 180ms ease; }
.menu-button[aria-expanded="true"] span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.menu-button[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-button[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }
.mobile-menu { position: fixed; inset: calc(var(--header-h) + 1px) 0 auto; z-index: 40; height: calc(100svh - var(--header-h) - 1px); padding: 16px 24px 32px; overflow-y: auto; background: var(--bg-0); }
.mobile-menu[hidden] { display: none; }
.mobile-menu a { display: flex; min-height: 56px; border-bottom: 1px solid var(--line); align-items: center; color: var(--text-1); font-size: 18px; font-weight: 500; text-decoration: none; }
.mobile-menu a[aria-current="page"] { color: var(--brand-1); }

/* Buttons */
.button { display: inline-flex; min-height: 48px; padding: 0 22px; border: 1px solid transparent; border-radius: var(--button-radius); align-items: center; justify-content: center; gap: 8px; font-size: 15px; font-weight: 600; line-height: 1.2; text-align: center; text-decoration: none; white-space: nowrap; cursor: pointer; transition: color 180ms ease, background 180ms ease, border-color 180ms ease, box-shadow 180ms ease, filter 180ms ease; }
.button-small { min-height: 38px; padding: 0 16px; font-size: 14px; }
.button-large { min-height: 54px; padding: 0 28px; font-size: 16px; }
.button-primary { color: var(--bg-0); background: var(--text-1); }
.button-primary:hover { background: #fff; box-shadow: 0 0 0 1px rgba(38, 220, 236, 0.35), 0 10px 44px -6px var(--brand-glow); }
.button-ghost { border-color: var(--line-strong); color: var(--text-1); background: rgba(255, 255, 255, 0.02); }
.button-ghost:hover { border-color: rgba(255, 255, 255, 0.28); background: rgba(255, 255, 255, 0.06); }
.button svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.text-action { display: inline-flex; min-height: 44px; align-items: center; gap: 6px; color: var(--brand-1); font-size: 15px; font-weight: 500; text-decoration: none; transition: gap 180ms var(--ease-out), color 180ms ease; }
.text-action:hover { gap: 10px; color: #7ff0fa; }
.button[aria-disabled="true"] { opacity: 0.55; pointer-events: none; }

/* Segmented control and tags */
.tag { display: inline-flex; padding: 4px 10px; border-radius: 999px; color: var(--brand-1); background: rgba(38, 220, 236, 0.1); font-size: 12px; font-weight: 600; }
.segmented { display: inline-flex; padding: 4px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--bg-2); }
.segmented [role="tab"] { min-height: 40px; padding: 0 22px; border: 0; border-radius: 9px; color: var(--text-2); background: transparent; font-size: 14px; font-weight: 600; cursor: pointer; transition: color 160ms ease, background 160ms ease; }
.segmented [role="tab"]:hover { color: var(--text-1); }
.segmented [role="tab"][aria-selected="true"] { color: var(--text-1); background: var(--bg-3); box-shadow: inset 0 0 0 1px var(--line-strong); }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* Cards with cursor spotlight */
.spot { position: relative; isolation: isolate; }
.spot::before { content: ""; position: absolute; inset: 0; z-index: -1; border-radius: inherit; background: radial-gradient(360px circle at var(--mx, 50%) var(--my, 0%), rgba(38, 220, 236, 0.09), transparent 70%); opacity: 0; transition: opacity 300ms ease; pointer-events: none; }
.spot:hover::before { opacity: 1; }

/* FAQ */
.faq-layout { display: grid; align-items: start; grid-template-columns: 0.72fr 1.28fr; gap: clamp(40px, 7vw, 96px); }
.faq-layout h2 { margin: 0; color: var(--text-1); font-size: clamp(30px, 3.2vw, 44px); font-weight: 650; line-height: 1.15; letter-spacing: -0.01em; }
.faq-layout > div:first-child > p:last-child { max-width: 400px; margin: 20px 0 0; color: var(--text-2); }
.faq-list { border-top: 1px solid var(--line-strong); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; display: flex; min-height: 72px; padding: 18px 44px 18px 0; align-items: center; color: var(--text-1); font-size: 17px; font-weight: 600; cursor: pointer; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; right: 4px; color: var(--brand-1); font-size: 24px; font-weight: 400; }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { margin: -4px 0 22px; padding-right: 50px; color: var(--text-2); }

/* Final CTA */
.final-cta { position: relative; overflow: hidden; padding: var(--section-y) 0; border-top: 1px solid var(--line); text-align: center; background: radial-gradient(60% 70% at 50% 100%, rgba(38, 220, 236, 0.14), transparent 70%), var(--bg-0); }
.final-cta-inner { display: flex; align-items: center; flex-direction: column; }
.final-cta img { width: 64px; height: 64px; margin-bottom: 28px; }
.final-cta h2 { max-width: 720px; margin: 0; color: var(--text-1); font-size: clamp(34px, 4.4vw, 60px); font-weight: 700; line-height: 1.1; letter-spacing: -0.02em; }
.final-cta p { max-width: 560px; margin: 18px 0 0; color: var(--text-2); font-size: 18px; }
.cta-actions { display: flex; margin-top: 36px; align-items: center; justify-content: center; flex-wrap: wrap; gap: 12px 24px; }

/* Footer */
.site-footer { padding: 72px 0 32px; border-top: 1px solid var(--line); color: var(--text-1); background: var(--bg-0); }
.footer-grid { display: grid; grid-template-columns: 1.7fr repeat(4, 1fr); gap: 42px; }
.footer-brand p { max-width: 280px; margin: 14px 0 0; color: var(--text-3); font-size: 14px; }
.footer-grid h2 { margin: 8px 0 14px; color: var(--text-1); font-size: 13px; font-weight: 600; }
.footer-grid > div:not(.footer-brand) > a { display: block; min-height: 34px; color: var(--text-3); font-size: 14px; text-decoration: none; transition: color 160ms ease; }
.footer-grid > div:not(.footer-brand) > a:hover { color: var(--text-1); }
.footer-grid > div:not(.footer-brand) > a[aria-current="page"] { color: var(--text-2); }
.footer-bottom { display: flex; margin-top: 56px; padding-top: 24px; border-top: 1px solid var(--line); align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 12px; color: var(--text-3); font-size: 13px; }
.footer-bottom span { display: inline-flex; gap: 4px; }

/* 404 */
.not-found { display: flex; min-height: 100svh; padding: 48px 24px; align-items: center; justify-content: center; flex-direction: column; color: var(--text-1); text-align: center; background: radial-gradient(60% 50% at 50% 0%, rgba(38, 220, 236, 0.14), transparent 70%), var(--bg-0); }
.not-found > p { margin: 56px 0 0; color: var(--brand-1); font-family: var(--font-mono); font-size: 18px; }
.not-found h1 { margin: 8px 0 28px; font-size: clamp(32px, 5vw, 48px); letter-spacing: -0.03em; }

/* Reveal (progressive enhancement: main.js adds .reveal-on) */
html.reveal-on [data-reveal] { opacity: 0; transform: translateY(24px); }
html.reveal-on [data-reveal].is-visible { opacity: 1; transform: none; transition: opacity 720ms var(--ease-out), transform 720ms var(--ease-out); }
@keyframes rise { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
@keyframes breathe { 0%, 100% { opacity: 0.75; } 50% { opacity: 1; } }

@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 800px) {
  .desktop-nav, .nav-actions .text-link, .nav-actions .button { display: none; }
  .menu-button { display: inline-flex; }
  .nav-shell { gap: 16px; }
  .faq-layout { grid-template-columns: 1fr; gap: 32px; }
}
@media (max-width: 560px) {
  .section-shell, .nav-shell { width: min(calc(100% - 32px), var(--max-width)); }
  .cta-actions { flex-direction: column; width: 100%; }
  .cta-actions .button { width: 100%; }
  .footer-grid { gap: 28px 20px; }
  .faq-list details p { padding-right: 0; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html.reveal-on [data-reveal] { opacity: 1; transform: none; }
}