/* ─── Reset & Base ─────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:           #080809;
  --bg-surface:   #0f0f11;
  --bg-elevated:  #161619;
  --bg-code:      #0d0d10;

  --text:         #e1e1e6;
  --text-muted:   #71717a;
  --text-subtle:  #3f3f46;

  --green:        #22c55e;
  --green-dim:    #16a34a;
  --green-bg:     rgba(34, 197, 94, 0.08);
  --red:          #ef4444;
  --red-bg:       rgba(239, 68, 68, 0.08);
  --blue:         #60a5fa;
  --yellow:       #fbbf24;

  --border:       #27272a;
  --border-muted: #1c1c1e;

  --font-sans:  -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --font-mono:  ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --radius:    6px;
  --max-w:     960px;
  --section-y: 96px;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* ─── Layout Helpers ────────────────────────────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

section {
  padding: var(--section-y) 0;
  border-bottom: 1px solid var(--border-muted);
}

section:last-of-type { border-bottom: none; }

/* ─── Navigation ────────────────────────────────────────────────────────────── */
nav {
  position: -webkit-sticky;
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(8, 8, 9, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-muted);
  padding: 0 24px;
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 52px;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav-logo span { color: var(--green); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.15s;
}

.nav-links a:hover { color: var(--text); }

/* ─── Hero ──────────────────────────────────────────────────────────────────── */
#hero {
  padding: 112px 0 96px;
  border-bottom: 1px solid var(--border-muted);
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 28px;
}

.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green);
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 700;
  line-height: 1.12;
  letter-spacing: -0.03em;
  color: #f4f4f5;
  max-width: 720px;
  margin-bottom: 20px;
}

.hero-sub {
  font-size: 1.125rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  max-width: 540px;
}

.hero-rule {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-subtle);
  margin-bottom: 44px;
}

.hero-rule strong {
  color: var(--red);
  font-weight: 500;
}

.cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 18px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  transition: opacity 0.15s, background 0.15s;
  white-space: nowrap;
}

.btn-primary {
  background: var(--green-dim);
  color: #f0fdf4;
}

.btn-primary:hover { background: var(--green); }

.btn-secondary {
  background: #f4f4f5;
  color: #0a0a0b;
  border: 1px solid #f4f4f5;
  font-weight: 600;
}

.btn-secondary:hover { background: #ffffff; border-color: #ffffff; }

.btn-ghost {
  color: var(--text-muted);
  background: transparent;
  padding-left: 0;
}

.btn-ghost:hover { color: var(--text); }

/* ─── Section Headers ───────────────────────────────────────────────────────── */
.section-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-subtle);
  margin-bottom: 12px;
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: #f4f4f5;
  margin-bottom: 8px;
}

.section-sub {
  font-size: 0.9375rem;
  color: var(--text-muted);
  margin-bottom: 48px;
  max-width: 560px;
}

/* ─── 30-Second Flow ────────────────────────────────────────────────────────── */
.flow-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.flow-step {
  padding: 24px 20px;
  border-right: 1px solid var(--border);
  position: relative;
}

.flow-step:last-child { border-right: none; }

.flow-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-subtle);
  letter-spacing: 0.05em;
  margin-bottom: 10px;
}

.flow-step-title {
  font-size: 0.8125rem;
  font-weight: 600;
  color: #f4f4f5;
  margin-bottom: 6px;
}

.flow-step-body {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.55;
}

.flow-step.allow  { background: var(--green-bg); }
.flow-step.deny   { background: var(--red-bg); }
.flow-step.allow .flow-step-title { color: var(--green); }
.flow-step.deny  .flow-step-title { color: var(--red); }

/* ─── Architecture Diagram ──────────────────────────────────────────────────── */
.arch-wrap {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 32px;
  overflow-x: auto;
}

.arch-diagram {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  min-width: 560px;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}

.arch-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 12px 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  min-width: 220px;
}

.arch-node-name {
  font-weight: 600;
  color: #f4f4f5;
  font-size: 0.8125rem;
}

.arch-node-detail {
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-top: 3px;
}

.arch-arrow {
  display: flex;
  flex-direction: column;
  align-items: center;
  color: var(--text-subtle);
  font-size: 0.7rem;
  padding: 6px 0;
  gap: 2px;
}

.arch-arrow .label {
  font-size: 0.65rem;
  letter-spacing: 0.04em;
}

.arch-arrow .line { color: var(--border); font-size: 1rem; }

.arch-split {
  display: flex;
  gap: 64px;
  align-items: flex-start;
  margin-top: 0;
}

.arch-branch {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
}

.arch-verdict {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 5px 16px;
  border-radius: 20px;
  font-weight: 700;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
}

.arch-verdict.allow {
  background: var(--green-bg);
  border: 1px solid rgba(34, 197, 94, 0.3);
  color: var(--green);
}

.arch-verdict.deny {
  background: var(--red-bg);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: var(--red);
}

.arch-node.blocked {
  border-color: rgba(239, 68, 68, 0.3);
  background: var(--red-bg);
  min-width: 160px;
}

.arch-node.blocked .arch-node-name { color: var(--red); }
.arch-node.blocked .arch-node-detail { color: rgba(239,68,68,0.6); }

.arch-node.artifact {
  border-color: rgba(96, 165, 250, 0.3);
  background: rgba(96, 165, 250, 0.05);
}

.arch-node.artifact .arch-node-name { color: var(--blue); }

.arch-node.verifier {
  border-color: rgba(251, 191, 36, 0.3);
  background: rgba(251, 191, 36, 0.05);
}

.arch-node.verifier .arch-node-name { color: var(--yellow); }

.arch-node.executor { border-color: rgba(34, 197, 94, 0.3); }
.arch-node.executor .arch-node-name { color: var(--green); }

.arch-note {
  margin-top: 28px;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  font-size: 0.75rem;
  color: var(--text-muted);
  max-width: 560px;
  text-align: center;
  line-height: 1.6;
}

/* ─── Why Section ───────────────────────────────────────────────────────────── */
.why-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.why-card {
  padding: 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-surface);
}

.why-card-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-subtle);
  margin-bottom: 8px;
}

.why-card-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: #f4f4f5;
  margin-bottom: 6px;
}

.why-card-body {
  font-size: 0.8125rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.why-card.oxdeai {
  border-color: rgba(34, 197, 94, 0.3);
  background: var(--green-bg);
}

.why-card.oxdeai .why-card-title { color: var(--green); }

/* ─── Proof Blocks ──────────────────────────────────────────────────────────── */
.proof-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.proof-block {
  padding: 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-surface);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.proof-icon {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--green);
  font-weight: 700;
}

.proof-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #f4f4f5;
}

.proof-body {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.55;
}

/* ─── Demo Section ──────────────────────────────────────────────────────────── */
.demo-wrap {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.demo-header {
  padding: 10px 16px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.demo-dots {
  display: flex;
  gap: 5px;
}

.demo-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--border);
}

.demo-title-bar {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-subtle);
}

.demo-gif {
  display: block;
  width: 100%;
  height: auto;
}

.demo-caption {
  padding: 14px 20px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  line-height: 1.55;
}

.demo-caption span { color: var(--green); }
.demo-caption .red  { color: var(--red); }

/* ─── Code Snippets ─────────────────────────────────────────────────────────── */
.code-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0;
}

.code-tab {
  padding: 9px 16px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: color 0.15s;
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
  margin-bottom: -1px;
}

.code-tab.active {
  color: var(--green);
  border-bottom-color: var(--green);
}

.code-tab:hover { color: var(--text); }

.code-panel {
  display: none;
}

.code-panel.active { display: block; }

.code-block {
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.code-block-header {
  padding: 8px 16px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.code-lang {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-subtle);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.code-block pre {
  padding: 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.65;
  color: #c9d1d9;
}

/* Syntax colors */
.kw  { color: #ff7b72; }          /* keyword */
.fn  { color: #d2a8ff; }          /* function/method */
.str { color: #a5d6ff; }          /* string */
.cm  { color: #8b949e; font-style: italic; } /* comment */
.num { color: #79c0ff; }          /* number */
.ty  { color: #ffa657; }          /* type */
.op  { color: #ff7b72; }          /* operator */
.prop{ color: #79c0ff; }          /* property */

/* ─── Trust Model ───────────────────────────────────────────────────────────── */
.trust-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8125rem;
  margin-bottom: 32px;
}

.trust-table th {
  text-align: left;
  padding: 8px 16px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-subtle);
  border-bottom: 1px solid var(--border);
  font-weight: 500;
}

.trust-table td {
  padding: 12px 16px;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-muted);
  vertical-align: top;
}

.trust-table td:first-child {
  font-family: var(--font-mono);
  color: var(--text);
  font-weight: 500;
  white-space: nowrap;
}

.trust-callouts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 24px;
}

@media (max-width: 640px) {
  .trust-callouts { grid-template-columns: 1fr; }
}

.callout {
  padding: 16px;
  border-radius: var(--radius);
  border: 1px solid;
  font-size: 0.8rem;
}

.callout-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.callout-code {
  background: var(--bg-code);
  border-radius: 4px;
  padding: 10px 12px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  line-height: 1.6;
  margin-top: 8px;
  overflow-x: auto;
}

.callout.correct {
  border-color: rgba(34, 197, 94, 0.25);
  background: var(--green-bg);
}

.callout.correct .callout-label { color: var(--green); }

.callout.wrong {
  border-color: rgba(239, 68, 68, 0.25);
  background: var(--red-bg);
}

.callout.wrong .callout-label { color: var(--red); }

/* ─── Ecosystem ─────────────────────────────────────────────────────────────── */
.adapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 12px;
}

.adapter-card {
  padding: 16px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-surface);
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: border-color 0.15s;
}

.adapter-card:hover { border-color: #52525b; }

.adapter-name {
  font-weight: 600;
  font-size: 0.875rem;
  color: #f4f4f5;
}

.adapter-pkg {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
}

.adapter-note {
  font-size: 0.75rem;
  color: var(--text-subtle);
  line-height: 1.5;
}

.adapter-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  padding: 2px 7px;
  border-radius: 10px;
  border: 1px solid var(--border);
  color: var(--text-subtle);
  width: fit-content;
}

/* ─── Install Strip ─────────────────────────────────────────────────────────── */
.install-strip {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 40px;
}

.install-code {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text);
}

.install-code .prefix { color: var(--text-muted); }

/* ─── Footer ────────────────────────────────────────────────────────────────── */
footer {
  padding: 40px 0;
  border-top: 1px solid var(--border-muted);
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-brand {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.footer-brand span { color: var(--green); }

.footer-links {
  display: flex;
  gap: 20px;
  list-style: none;
}

.footer-links a {
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.15s;
}

.footer-links a:hover { color: var(--text); }

.footer-note {
  width: 100%;
  font-size: 0.75rem;
  color: var(--text-subtle);
  margin-top: 4px;
}

/* ─── Utilities ─────────────────────────────────────────────────────────────── */
.mono { font-family: var(--font-mono); }
.green { color: var(--green); }
.red   { color: var(--red); }
.muted { color: var(--text-muted); }

hr.section-rule {
  border: none;
  border-top: 1px solid var(--border-muted);
  margin: 32px 0;
}

/* ─── Light Mode ────────────────────────────────────────────────────────────── */
html.light {
  --bg:           #ffffff;
  --bg-surface:   #f7f7f9;
  --bg-elevated:  #efeff2;
  --bg-code:      #f3f3f6;

  --text:         #111113;
  --text-muted:   #52525b;
  --text-subtle:  #a1a1aa;

  --border:       #d4d4d8;
  --border-muted: #e4e4e7;

  --green-bg:     rgba(22, 163, 74, 0.08);
  --red-bg:       rgba(220, 38, 38, 0.08);
}

html.light body { color: var(--text); background: var(--bg); }

html.light .nav-links {
  background: rgba(255, 255, 255, 0.97);
  border-bottom-color: var(--border);
}

html.light .hero-title,
html.light .section-title,
html.light .flow-step-title,
html.light .arch-node-name,
html.light .why-card-title,
html.light .proof-title,
html.light .adapter-name { color: #111113; }

html.light .arch-node { background: var(--bg-elevated); }
html.light .arch-node.blocked { background: var(--red-bg); }
html.light .arch-node.artifact { background: rgba(59, 130, 246, 0.06); }
html.light .arch-node.verifier { background: rgba(202, 138, 4, 0.06); }
html.light .arch-wrap  { background: var(--bg-surface); }
html.light .arch-note  { background: var(--bg); }

html.light .code-block,
html.light .code-block pre { background: var(--bg-code); }
html.light .code-block pre { color: #24292f; }
html.light .code-block-header { background: var(--bg-elevated); }

html.light .kw   { color: #cf222e; }
html.light .fn   { color: #8250df; }
html.light .str  { color: #0a3069; }
html.light .cm   { color: #6e7781; }
html.light .num  { color: #0550ae; }
html.light .ty   { color: #953800; }
html.light .prop { color: #0550ae; }

html.light .callout-code { background: var(--bg-code); }
html.light .demo-wrap,
html.light .demo-header  { background: var(--bg-elevated); }

html.light .btn-secondary {
  background: #111113;
  color: #f4f4f5;
  border-color: #111113;
}
html.light .btn-secondary:hover { background: #27272a; border-color: #27272a; }

html.light nav {
  background: rgba(255, 255, 255, 0.92);
  border-bottom-color: var(--border);
}

/* ─── Theme Toggle Button ────────────────────────────────────────────────────── */
.nav-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.85rem;
  transition: background 0.15s, border-color 0.15s;
  flex-shrink: 0;
}

.theme-toggle:hover { border-color: #52525b; }

/* Show sun icon in dark mode, moon in light mode */
.theme-icon-dark  { display: inline; }
.theme-icon-light { display: none; }

html.light .theme-icon-dark  { display: none; }
html.light .theme-icon-light { display: inline; }

/* ─── Hamburger / Mobile Nav ────────────────────────────────────────────────── */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius);
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-muted);
  border-radius: 2px;
  transition: transform 0.2s, opacity 0.2s;
}

.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─── Table scroll wrapper ───────────────────────────────────────────────────── */
.table-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border-radius: var(--radius);
  margin-bottom: 32px;
}

.table-scroll .trust-table { margin-bottom: 0; }

/* ─── Install lines ─────────────────────────────────────────────────────────── */
.install-lines {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* ─── Responsive: tablet (≤768px) ──────────────────────────────────────────── */
@media (max-width: 768px) {
  :root { --section-y: 72px; }

  .container { padding: 0 20px; }

  .section-title { font-size: 1.35rem; }

  /* Nav */
  .nav-toggle { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: 52px;
    left: 0;
    right: 0;
    background: rgba(8, 8, 9, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    gap: 0;
    padding: 8px 0;
    z-index: 99;
  }

  .nav-links.open { display: flex; }

  .nav-links li { width: 100%; }

  .nav-links a {
    display: block;
    padding: 12px 24px;
    font-size: 0.9rem;
    border-bottom: 1px solid var(--border-muted);
  }

  .nav-links li:last-child a { border-bottom: none; }

  /* Arch diagram: stack the split branches */
  .arch-diagram { min-width: unset; width: 100%; }
  .arch-node    { min-width: unset; width: 100%; max-width: 360px; }

  .arch-split {
    flex-direction: column;
    align-items: center;
    gap: 24px;
    width: 100%;
  }

  .arch-branch { width: 100%; max-width: 320px; }

  /* Why grid: 2 cols on tablet */
  .why-grid { grid-template-columns: 1fr 1fr; }

  /* Proof grid: 2 cols */
  .proof-grid { grid-template-columns: 1fr 1fr; }

  /* Code tabs: scrollable */
  .code-block-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
  }

  .code-block-header > div:first-child {
    overflow-x: auto;
    width: 100%;
    display: flex;
    border-bottom: 1px solid var(--border);
  }

  .code-lang { padding: 6px 16px; }

  /* Install strip */
  .install-strip { flex-direction: column; align-items: flex-start; }
  .install-code  { font-size: 0.8rem; }

  /* Footer */
  .footer-inner { flex-direction: column; align-items: flex-start; gap: 12px; }
  .footer-links { flex-wrap: wrap; gap: 12px 20px; }
}

/* ─── Responsive: mobile (≤480px) ──────────────────────────────────────────── */
@media (max-width: 480px) {
  :root { --section-y: 56px; }

  .container { padding: 0 16px; }

  /* Hero */
  #hero { padding: 64px 0 52px; }
  .hero-title { font-size: clamp(1.6rem, 8vw, 2.25rem); }
  .hero-sub   { font-size: 1rem; }
  .cta-group  { flex-direction: column; align-items: flex-start; gap: 10px; }
  .btn        { width: 100%; justify-content: center; }
  .btn-ghost  { width: auto; justify-content: flex-start; }

  /* Flow grid: single column */
  .flow-grid { grid-template-columns: 1fr; }
  .flow-step { border-right: none; border-bottom: 1px solid var(--border); }
  .flow-step:last-child { border-bottom: none; }

  /* Arch: tighter */
  .arch-wrap { padding: 24px 16px; }
  .arch-node { padding: 10px 16px; }
  .arch-node-name   { font-size: 0.75rem; }
  .arch-node-detail { font-size: 0.65rem; }
  .arch-note { font-size: 0.7rem; padding: 10px 12px; }

  /* Why + Proof: single column */
  .why-grid   { grid-template-columns: 1fr; }
  .proof-grid { grid-template-columns: 1fr; }

  /* Code */
  .code-block pre { padding: 14px; font-size: 0.75rem; }
  .code-tab { padding: 8px 12px; font-size: 0.7rem; }

  /* Demo caption: shorter lines */
  .demo-caption { font-size: 0.75rem; padding: 12px 14px; }

  /* Trust callouts: stack */
  .trust-callouts { grid-template-columns: 1fr; }

  /* Adapter grid: 2 cols */
  .adapter-grid { grid-template-columns: 1fr 1fr; }

  /* Section sub: full width */
  .section-sub { max-width: 100%; }

  /* Install */
  .install-code { font-size: 0.75rem; word-break: break-all; }
}