:root {
  --ink: #0b1723;
  --muted: #526170;
  --paper: #f4f2ea;
  --paper-deep: #e8e4d7;
  --night: #08131f;
  --night-soft: #102236;
  --line: rgba(11, 23, 35, 0.17);
  --cyan: #3ddbd9;
  --lime: #c9f36a;
  --orange: #ff8a4c;
  --white: #fffefa;
  --max: 1180px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); line-height: 1.65; }
a { color: inherit; }
code, pre, kbd { font-family: "Cascadia Code", "SFMono-Regular", Consolas, monospace; }
code { font-size: .92em; }
.skip-link { position: fixed; top: 12px; left: 12px; z-index: 100; padding: 10px 14px; color: var(--night); background: var(--lime); transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }
.section-shell { width: min(calc(100% - 48px), var(--max)); margin-inline: auto; }
.section-shell.compact { max-width: 850px; text-align: center; }
.eyebrow, .section-kicker { margin: 0 0 18px; font-size: .76rem; font-weight: 800; letter-spacing: .18em; text-transform: uppercase; color: #236f75; }

.site-header { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; min-height: 72px; padding: 0 max(24px, calc((100vw - var(--max)) / 2)); color: var(--white); background: rgba(8, 19, 31, .94); border-bottom: 1px solid rgba(255,255,255,.12); backdrop-filter: blur(14px); }
.wordmark { display: flex; gap: 10px; align-items: center; text-decoration: none; font-weight: 800; letter-spacing: -.02em; }
.wordmark span { color: var(--cyan); font-family: monospace; }
.site-header nav { display: flex; gap: 28px; align-items: center; }
.site-header nav a { color: #d7e1e8; font-size: .9rem; font-weight: 650; text-decoration: none; }
.site-header nav a:hover, .site-header nav a:focus-visible { color: var(--cyan); }

.hero { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(380px, .95fr); gap: clamp(48px, 8vw, 100px); align-items: center; min-height: 720px; padding-block: 100px; }
.hero h1 { max-width: 800px; margin: 0; font-size: clamp(3rem, 6.2vw, 6.4rem); line-height: .96; letter-spacing: -.065em; }
.hero-lede { max-width: 690px; margin: 34px 0 0; font-size: clamp(1.1rem, 2vw, 1.35rem); color: var(--muted); }
.button-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 36px; }
.button-row.centered { justify-content: center; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 50px; padding: 0 22px; border: 1px solid var(--ink); text-decoration: none; font-weight: 800; transition: transform .16s ease, box-shadow .16s ease; }
.button:hover { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 var(--ink); }
.button.primary { color: var(--night); background: var(--lime); }
.button.secondary { color: var(--ink); background: transparent; }
.cta-band .button.secondary { color: var(--white); border-color: rgba(255,255,255,.65); }
.proof-row { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 30px; color: #44515d; font-size: .84rem; font-weight: 700; }
.proof-row span::before { content: "✓"; margin-right: 7px; color: #1d7773; }

.terminal-card { overflow: hidden; color: #d9e4eb; background: var(--night); border: 1px solid #1c3850; box-shadow: 18px 18px 0 var(--paper-deep); transform: rotate(1deg); }
.terminal-bar { display: flex; gap: 8px; align-items: center; padding: 14px 18px; background: var(--night-soft); border-bottom: 1px solid #22405a; }
.terminal-bar i { width: 10px; height: 10px; border-radius: 50%; background: #385269; }
.terminal-bar i:first-child { background: var(--orange); }
.terminal-bar i:nth-child(2) { background: #f4c65d; }
.terminal-bar i:nth-child(3) { background: var(--lime); }
.terminal-bar span { margin-left: auto; font: .72rem monospace; color: #8da1b1; }
.terminal-card pre { min-height: 350px; margin: 0; padding: 34px; white-space: pre-wrap; font-size: clamp(.9rem, 1.4vw, 1.08rem); line-height: 1.72; }
.muted { color: #708798; }.error { color: #ff866f; }.success { color: var(--lime); }.cyan { color: var(--cyan); }.cursor { color: var(--cyan); animation: blink 1.2s step-end infinite; }
@keyframes blink { 50% { opacity: 0; } }

.problem-band { padding: 90px 0; color: var(--white); background: var(--night); }
.problem-band .section-kicker, .cta-band .section-kicker { color: var(--cyan); }
.problem-band h2, .cta-band h2 { margin: 0; font-size: clamp(2.2rem, 5vw, 4.4rem); line-height: 1.05; letter-spacing: -.045em; }
.problem-band p:last-child { margin: 28px auto 0; color: #bbc9d2; font-size: 1.1rem; }
.content-section { padding-block: 110px; border-bottom: 1px solid var(--line); }
.content-section h2 { max-width: 820px; margin: 0 0 48px; font-size: clamp(2.2rem, 4vw, 4rem); line-height: 1.06; letter-spacing: -.045em; }

.flow-grid { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); }
.flow-grid article { min-height: 290px; padding: 34px; border-right: 1px solid var(--line); }
.flow-grid article:last-child { border-right: 0; }
.flow-grid .step { display: block; margin-bottom: 54px; color: #267077; font: 700 .82rem monospace; }
.flow-grid strong { display: block; font-size: 1.5rem; }
.flow-grid p { color: var(--muted); }
.pipeline { display: flex; justify-content: center; align-items: center; gap: 18px; margin-top: 28px; padding: 22px; color: #dce8ee; background: var(--night); font: 700 .82rem monospace; overflow-x: auto; }
.pipeline b { color: var(--cyan); }

.split-section { display: grid; grid-template-columns: .85fr 1.15fr; gap: clamp(50px, 8vw, 110px); align-items: center; }
.split-section h2 { margin-bottom: 26px; }
.check-list { padding: 0; list-style: none; }
.check-list li { margin: 12px 0; color: var(--muted); }
.check-list li::before { content: "→"; margin-right: 10px; color: #1c7576; font-weight: 900; }
.code-card { overflow: hidden; color: #dce8ee; background: var(--night); box-shadow: 12px 12px 0 var(--paper-deep); }
.code-label { padding: 13px 20px; color: var(--cyan); background: var(--night-soft); font: 700 .7rem monospace; letter-spacing: .16em; }
.code-card pre { margin: 0; padding: 28px; overflow-x: auto; font-size: .88rem; line-height: 1.75; }
.command-strip { max-width: 760px; margin-bottom: 25px; padding: 24px 28px; color: var(--lime); background: var(--night); font-size: 1.05rem; }
kbd { padding: 3px 7px; background: var(--white); border: 1px solid #acb2b4; border-bottom-width: 3px; border-radius: 4px; font-size: .82em; }
.notice-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.notice-grid article { padding: 28px; background: rgba(255,255,255,.46); border: 1px solid var(--line); }
.notice-grid strong { font-size: 1.08rem; }
.notice-grid p { margin-bottom: 0; color: var(--muted); }
.cta-band { padding: 100px 0; color: var(--white); background: #102c3e; }
.site-footer { display: flex; justify-content: space-between; gap: 24px; padding-block: 34px; color: var(--muted); font-size: .82rem; }

.language-gate { min-height: 100vh; color: var(--white); background: var(--night); }
.language-gate::before { content: ""; position: fixed; inset: 0; pointer-events: none; background: linear-gradient(rgba(61,219,217,.055) 1px, transparent 1px), linear-gradient(90deg, rgba(61,219,217,.055) 1px, transparent 1px); background-size: 48px 48px; mask-image: linear-gradient(to bottom, black, transparent 85%); }
.gate-shell { position: relative; display: flex; flex-direction: column; justify-content: center; min-height: 100vh; width: min(calc(100% - 48px), 980px); margin: auto; padding: 72px 0; }
.brand-mark { display: grid; place-items: center; width: 62px; height: 62px; margin-bottom: 40px; color: var(--night); background: var(--cyan); font: 900 1.15rem monospace; box-shadow: 7px 7px 0 rgba(201,243,106,.8); }
.gate-shell h1 { margin: 0; font-size: clamp(3.4rem, 9vw, 7.8rem); line-height: .84; letter-spacing: -.075em; }
.gate-lede { max-width: 700px; margin: 36px 0 0; color: #b8c8d3; font-size: 1.18rem; }
.gate-lede.zh { margin-top: 8px; }
.language-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; max-width: 700px; margin-top: 42px; }
.language-card { display: grid; grid-template-columns: 56px 1fr; grid-template-rows: auto auto; column-gap: 18px; padding: 22px; color: var(--white); border: 1px solid #315068; text-decoration: none; transition: background .18s ease, border-color .18s ease, transform .18s ease; }
.language-card:hover, .language-card:focus-visible, .language-card.recommended { background: var(--night-soft); border-color: var(--cyan); transform: translateY(-2px); }
.language-code { grid-row: 1 / 3; display: grid; place-items: center; color: var(--night); background: var(--lime); font: 900 .78rem monospace; }
.language-card strong { font-size: 1.12rem; }
.language-card > span:last-child { color: #91a5b3; font-size: .83rem; }
.language-hint { min-height: 26px; color: var(--cyan); font-size: .82rem; }
.signal-line { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; color: #8196a5; font: 700 .72rem monospace; }
.signal-line b { color: var(--cyan); }
.text-link { align-self: flex-start; margin-top: 28px; color: #d9e4ea; text-underline-offset: 5px; }

@media (max-width: 800px) {
  .site-header { position: static; align-items: flex-start; padding-block: 20px; }
  .site-header nav { gap: 14px; flex-wrap: wrap; justify-content: flex-end; }
  .site-header nav a:not(:last-child) { display: none; }
  .hero { grid-template-columns: 1fr; min-height: auto; padding-block: 72px; }
  .terminal-card { max-width: 620px; transform: none; }
  .flow-grid, .split-section { grid-template-columns: 1fr; }
  .flow-grid article { min-height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .flow-grid article:last-child { border-bottom: 0; }
  .flow-grid .step { margin-bottom: 26px; }
  .notice-grid { grid-template-columns: 1fr; }
  .site-footer { flex-direction: column; }
}

@media (max-width: 560px) {
  .section-shell, .gate-shell { width: min(calc(100% - 30px), var(--max)); }
  .content-section { padding-block: 76px; }
  .hero h1 { font-size: 3.25rem; }
  .language-grid { grid-template-columns: 1fr; }
  .pipeline { justify-content: flex-start; }
  .terminal-card pre { padding: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}