@media (max-width: 1180px) {
  .hero-section { grid-template-columns: 1fr; padding-top: 40px; }
  .hero-copy { text-align: center; }
  .hero-copy h1, .hero-copy > p { margin-left: auto; margin-right: auto; }
  .hero-actions, .hero-trust { justify-content: center; }
  .hero-preview-wrap { max-width: 900px; width: 100%; margin: 0 auto; }
  .split-heading, .process-language-section, .privacy-section { grid-template-columns: 1fr; }
  .privacy-copy { justify-self: start; }
  .model-tier-grid { grid-template-columns: repeat(2, 1fr); }
  .process-card-grid { grid-template-columns: repeat(2, 1fr); }
  .home-grid { grid-template-columns: 1fr; }
  .editor-layout, .run-detail-grid { grid-template-columns: 1fr 300px; }
}

@media (max-width: 900px) {
  :root { --sidebar: 72px; }
  .studio-sidebar { padding: 18px 10px; }
  .studio-brand .brand-word, .studio-nav-item span, .local-badge div { display: none; }
  .studio-nav-item { justify-content: center; padding: 0; }
  .local-badge { justify-content: center; padding: 12px 0; }
  .start-choice-grid, .choice-grid { grid-template-columns: 1fr; }
  .product-preview { transform: none; }
  .marketing-nav nav { display: none; }
  .marketing-nav { padding: 0 24px; }
  .marketing-section, .process-language-section { padding-left: 24px; padding-right: 24px; }
  .hero-section { padding-left: 24px; padding-right: 24px; }
  .callout-left { left: 8px; }
  .callout-right { right: 8px; }
  .final-cta { margin-left: 24px; margin-right: 24px; grid-template-columns: 60px 1fr; }
  .final-cta .button { grid-column: 1 / -1; }
  .marketing-footer { grid-template-columns: 1fr 1fr; padding-left: 24px; padding-right: 24px; }
  .page-header { align-items: flex-start; flex-direction: column; }
  .process-card-grid { grid-template-columns: 1fr; }
  .editor-layout, .run-detail-grid { grid-template-columns: 1fr; }
  .step-inspector, .run-summary-panel { border-left: 0; border-top: 1px solid var(--border); }
  .builder-layout { grid-template-columns: 220px 1fr; }
  .capability-summary, .metric-strip { grid-template-columns: 1fr; }
  .model-specs { grid-template-columns: 1fr 1fr; }
  .model-specs > div:nth-child(2) { border-right: 0; }
  .model-specs > div:nth-child(-n+2) { border-bottom: 1px solid var(--border); }
}

@media (max-width: 680px) {
  .marketing-nav { height: 70px; }
  .marketing-nav .button { display: none; }
  .hero-section { padding-top: 42px; gap: 40px; }
  .hero-copy h1 { font-size: 52px; }
  .hero-copy > p { font-size: 16px; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-trust { grid-template-columns: 1fr; text-align: left; }
  .product-preview { min-height: 440px; grid-template-columns: 52px 1fr; border-radius: 18px; }
  .preview-rail { padding: 12px 9px; }
  .preview-canvas { grid-template-columns: 1fr; }
  .preview-inspector { display: none; }
  .hero-callout, .preview-orbit { display: none; }
  .proof-strip { overflow: hidden; justify-content: flex-start; padding: 0 24px; }
  .split-heading { gap: 24px; }
  .section-heading h2, .process-language-copy h2, .privacy-copy h2 { font-size: 42px; }
  .process-paper { padding: 28px; }
  .model-tier-grid { grid-template-columns: 1fr; }
  .assistant-boundary { grid-template-columns: 1fr; gap: 18px; }
  .boundary-arrow { transform: rotate(90deg); }
  .privacy-section { padding: 90px 24px; }
  .privacy-items { grid-template-columns: 1fr; }
  .privacy-lock { position: static; margin-top: 14px; justify-self: center; }
  .pack-list article { grid-template-columns: 48px 1fr; }
  .pack-list small { grid-column: 2; width: fit-content; }
  .final-cta { grid-template-columns: 1fr; text-align: center; padding: 32px 24px; }
  .final-cta-mark { justify-self: center; }
  .marketing-footer { grid-template-columns: 1fr; text-align: center; justify-items: center; }
  body.is-demo { overflow: auto; }
  .studio-app { display: block; }
  .studio-sidebar { position: fixed; bottom: 0; top: auto; left: 0; width: 100%; height: 66px; padding: 8px 12px; display: block; z-index: 60; }
  .studio-brand, .sidebar-bottom, .studio-nav-item span { display: none; }
  .studio-nav { display: grid; grid-template-columns: repeat(5, 1fr); gap: 4px; }
  .studio-nav-item { height: 48px; min-height: 48px; }
  .studio-workspace { height: auto; min-height: 100vh; padding-bottom: 66px; }
  .studio-topbar { position: sticky; top: 0; z-index: 20; }
  .demo-banner p, .model-chip small, .model-chip strong { display: none; }
  .model-chip { width: 38px; grid-template-columns: 1fr; padding: 0; place-items: center; }
  .model-chip-dot { grid-row: auto; }
  .studio-content { height: auto; min-height: calc(100vh - 72px); overflow: visible; padding: 24px 16px 90px; }
  .page-header h1 { font-size: 32px; }
  .start-choice-grid { grid-template-columns: 1fr; }
  .activity-panel, .runs-table { overflow-x: auto; }
  .filter-bar { align-items: stretch; flex-direction: column; gap: 10px; }
  .search-box { min-width: 0; }
  .editor-page, .run-detail-page, .builder-page { margin: -24px -16px -90px; min-height: 100vh; }
  .editor-header { align-items: flex-start; flex-direction: column; }
  .editor-actions { width: 100%; flex-wrap: wrap; }
  .process-document { margin: 24px 12px 40px; padding: 18px; }
  .process-sentence { grid-template-columns: 68px 1fr; }
  .sentence-controls { display: none; }
  .builder-top { padding: 0 12px; }
  .builder-top > div { display: none; }
  .builder-layout { grid-template-columns: 1fr; }
  .builder-progress { display: none; }
  .builder-question { padding: 34px 18px 100px; }
  .builder-question h1 { font-size: 32px; }
  .builder-footer { position: fixed; left: 0; right: 0; bottom: 66px; padding: 10px 14px; background: var(--white); border-top: 1px solid var(--border); z-index: 50; }
  .builder-footer > span { display: none; }
  .settings-layout { grid-template-columns: 1fr; }
  .settings-nav { display: flex; overflow-x: auto; }
  .settings-nav button { white-space: nowrap; }
  .model-specs { grid-template-columns: 1fr; }
  .model-specs > div { border-right: 0; border-bottom: 1px solid var(--border); }
  .assistant-panel { width: min(100%, 390px); }
  .assistant-is-open .studio-workspace { filter: brightness(.75); pointer-events: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .001ms !important; animation-duration: .001ms !important; }
}