/* ==========================================================================
   Next EV To Do — Design System
   Premium industrial-technology aesthetic: charcoal, warm off-white,
   metallic gray, restrained burnt-orange accent. Flat surfaces, hairline
   rules, no gradients, no glow, no heavy rounding.
   ========================================================================== */

@font-face {
  font-family: "Archivo";
  src: url("/assets/vendor/fonts/archivo-variable.woff2") format("woff2-variations"),
       url("/assets/vendor/fonts/archivo-variable.woff2") format("woff2");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Source Serif";
  src: url("/assets/vendor/fonts/source-serif-variable.woff2") format("woff2-variations"),
       url("/assets/vendor/fonts/source-serif-variable.woff2") format("woff2");
  font-weight: 300 700;
  font-style: normal;
  font-display: swap;
}

:root {
  /* Charcoal (dark surfaces) */
  --charcoal-950: #14130f;
  --charcoal-900: #1b1a16;
  --charcoal-800: #26241f;
  --charcoal-700: #3a3730;
  --charcoal-600: #524e45;

  /* Warm off-white (light surfaces) */
  --warm-50: #faf7f2;
  --warm-100: #f2ede3;
  --warm-200: #e7ddcd;
  --warm-300: #d6c9b2;

  /* Metallic gray */
  --metal-300: #b7ae9e;
  --metal-500: #8c8375;
  --metal-700: #5f594d;

  /* Ink */
  --ink: #1e1c17;
  --ink-soft: #55503f;
  --ink-on-dark: #ede8dd;
  --ink-on-dark-soft: #b6ae9d;

  /* Burnt orange accent */
  --rust-700: #8a3714;
  --rust-600: #a8451b;
  --rust-500: #bc5426;
  --rust-400: #d97c4a;
  --rust-100: #f1dac6;
  --rust-50: #f8ede3;

  --font-display: "Archivo", "Segoe UI", Arial, sans-serif;
  --font-serif: "Source Serif", Georgia, "Times New Roman", serif;
  --font-mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;

  --radius-sm: 2px;
  --radius-md: 3px;
  --max-width: 1220px;
  --rule: 1px solid var(--warm-300);
  --rule-dark: 1px solid var(--charcoal-700);
}

/* ---------- Reset ---------- */
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}
body {
  margin: 0;
  font-family: var(--font-serif);
  color: var(--ink);
  background: var(--warm-50);
  line-height: 1.65;
  font-size: 1.05rem;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  line-height: 1.1;
  margin: 0 0 0.5em;
  color: var(--ink);
  font-weight: 800;
  letter-spacing: -0.01em;
}
h1 { font-size: clamp(2.4rem, 4.6vw, 3.75rem); }
h2 { font-size: clamp(1.7rem, 2.9vw, 2.4rem); }
h3 { font-size: 1.2rem; font-weight: 700; font-family: var(--font-display); }
p { margin: 0 0 1.1em; color: var(--ink-soft); max-width: 66ch; }
a { color: var(--rust-600); text-decoration: none; }
/* Dark-background contexts: rust-600 only hits ~3.1:1 on charcoal — swap to the
   lighter tint so inline links stay at AA contrast (4.5:1+) wherever they land. */
.hero a, .page-hero a, .section-dark a, .cta-band a, .site-footer a, .contact-info-card a {
  color: var(--rust-400);
}
a:hover { text-decoration: underline; }
ul { padding-left: 1.2em; color: var(--ink-soft); }
strong { color: var(--ink); font-weight: 700; }
:focus-visible {
  outline: 3px solid var(--rust-700);
  outline-offset: 2px;
}
/* Dark-background contexts: swap to a lighter accent so the ring stays >=4.5:1 against charcoal. */
.hero :focus-visible,
.page-hero :focus-visible,
.section-dark :focus-visible,
.cta-band :focus-visible,
.site-footer :focus-visible,
.contact-info-card :focus-visible {
  outline-color: var(--rust-400);
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 28px;
}

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--rust-600);
  color: var(--warm-50);
  padding: 12px 18px;
  z-index: 1000;
  font-family: var(--font-display);
  font-weight: 700;
}
.skip-link:focus { left: 0; }

/* ---------- Technical grid backdrop (used sparingly: hero + one feature band) ---------- */
.tech-grid {
  background-image:
    linear-gradient(rgba(237, 232, 221, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(237, 232, 221, 0.05) 1px, transparent 1px);
  background-size: 42px 42px;
}
.tech-grid-light {
  background-image:
    linear-gradient(rgba(30, 28, 23, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 28, 23, 0.05) 1px, transparent 1px);
  background-size: 42px 42px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 15px 28px;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  border-radius: var(--radius-sm);
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  text-decoration: none;
  line-height: 1.1;
  white-space: nowrap;
}
.btn-primary {
  background: var(--rust-600);
  color: var(--warm-50);
  border-color: var(--rust-600);
}
.btn-primary:hover { background: var(--rust-700); border-color: var(--rust-700); text-decoration: none; }
.btn-secondary {
  background: transparent;
  color: var(--ink-on-dark);
  border-color: var(--charcoal-600);
}
.btn-secondary:hover { background: rgba(237, 232, 221, 0.08); border-color: var(--ink-on-dark-soft); text-decoration: none; }
.btn-outline-ink {
  background: transparent;
  color: var(--ink);
  border-color: var(--ink);
}
.btn-outline-ink:hover { background: var(--ink); color: var(--warm-50); text-decoration: none; }
.btn-block { width: 100%; }
.btn-lg { padding: 17px 32px; font-size: 1rem; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 500;
  background: var(--warm-50);
  border-bottom: var(--rule);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 28px;
  max-width: var(--max-width);
  margin: 0 auto;
  gap: 20px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-weight: 800;
  color: var(--ink);
  font-size: 1.12rem;
  letter-spacing: -0.005em;
}
.logo:hover { text-decoration: none; }
.logo-mark {
  width: 30px; height: 30px;
  flex-shrink: 0;
}
.logo-text-sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  font-weight: 500;
  color: var(--metal-500);
  letter-spacing: 0.09em;
  text-transform: uppercase;
  margin-top: 2px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-links {
  display: flex;
  gap: 30px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  color: var(--ink-soft);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.92rem;
  padding: 6px 0;
  border-bottom: 2px solid transparent;
}
.nav-links a:hover, .nav-links a[aria-current="page"] {
  color: var(--ink);
  border-bottom-color: var(--rust-600);
  text-decoration: none;
}
.nav-cta { white-space: nowrap; }

.nav-toggle {
  display: none;
  background: none;
  border: 1.5px solid var(--warm-300);
  border-radius: var(--radius-sm);
  padding: 9px 11px;
  cursor: pointer;
}
.nav-toggle svg { display: block; }

@media (max-width: 1080px) {
  .nav-toggle { display: inline-flex; }
  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--warm-50);
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border-bottom: var(--rule);
    box-shadow: 0 12px 24px rgba(20, 19, 15, 0.12);
    display: none;
  }
  .main-nav.is-open { display: flex; }
  .nav-links {
    flex-direction: column;
    gap: 0;
    padding: 10px 28px;
  }
  .nav-links a { display: block; padding: 13px 0; border-bottom: 1px solid var(--warm-200); }
  .nav-cta-wrap { padding: 18px 28px 24px; }
}

/* ---------- Hero ---------- */
.hero {
  background: var(--charcoal-950);
  color: var(--ink-on-dark);
  position: relative;
  overflow: hidden;
}
.hero-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 76px 28px 64px;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
  position: relative;
  z-index: 1;
}
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; padding: 52px 24px 48px; gap: 36px; }
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--rust-400);
  margin-bottom: 22px;
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1.5px;
  background: var(--rust-500);
  display: inline-block;
}
.hero h1 { color: var(--ink-on-dark); margin-bottom: 22px; font-size: clamp(2.5rem, 4.8vw, 3.9rem); }
.hero-lede {
  font-family: var(--font-serif);
  color: var(--ink-on-dark-soft);
  font-size: 1.2rem;
  max-width: 540px;
  margin-bottom: 30px;
  line-height: 1.55;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 20px; }
.hero-qualifier {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--ink-on-dark-soft);
  border-top: 1px solid var(--charcoal-700);
  padding-top: 16px;
  max-width: 540px;
}

.hero-media {
  position: relative;
  background: var(--charcoal-900);
  border: 1px solid var(--charcoal-700);
  border-top: 3px solid var(--rust-600);
  padding: 28px;
}
.hero-media img {
  width: 100%;
  height: auto;
  filter: invert(1) brightness(0.94) contrast(1.08);
}
.hero-media figcaption {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-on-dark-soft);
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--charcoal-700);
}

.page-hero {
  background: var(--charcoal-950);
  color: var(--ink-on-dark);
  padding: 60px 0 56px;
  position: relative;
}
.page-hero-inner { max-width: 720px; }
.page-hero p { color: var(--ink-on-dark-soft); font-size: 1.1rem; font-family: var(--font-serif); }
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--metal-300);
  margin-bottom: 18px;
}
.breadcrumb a { color: var(--metal-300); }
.page-hero h1 { color: var(--ink-on-dark); }

/* ---------- Sections ---------- */
section { padding: 76px 0; }
.section-alt { background: var(--warm-100); }
.section-dark { background: var(--charcoal-950); color: var(--ink-on-dark); }
.section-dark h2, .section-dark h3 { color: var(--ink-on-dark); }
.section-dark p { color: var(--ink-on-dark-soft); }
.section-tight { padding: 44px 0; }
.section-head { max-width: 680px; margin-bottom: 44px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.kicker {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--rust-600);
  font-weight: 600;
  display: block;
  margin-bottom: 12px;
}
.section-dark .kicker { color: var(--rust-400); }

/* ---------- Grids / cards ---------- */
.grid { display: grid; gap: 1px; background: var(--warm-300); border: 1px solid var(--warm-300); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-5 { grid-template-columns: repeat(5, 1fr); }
@media (max-width: 900px) {
  .grid-3, .grid-5 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .grid-3, .grid-5, .grid-2 { grid-template-columns: 1fr; }
}
.section-dark .grid { background: var(--charcoal-700); border-color: var(--charcoal-700); }

.card {
  background: var(--warm-50);
  padding: 32px 28px;
}
.section-dark .card { background: var(--charcoal-950); }
.card h3 { margin-bottom: 10px; }
.card p:last-child { margin-bottom: 0; }
.card-index {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--rust-600);
  margin-bottom: 14px;
  display: block;
}

/* ---------- Placeholder blocks ---------- */
.placeholder {
  border: 1.5px dashed var(--metal-300);
  background: var(--warm-100);
  padding: 34px 22px;
  text-align: center;
  color: var(--ink-soft);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 220px;
}
.placeholder-icon { color: var(--metal-500); }
.placeholder-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  background: var(--ink);
  color: var(--warm-50);
  padding: 4px 10px;
}
.placeholder-title { font-family: var(--font-display); font-weight: 700; color: var(--ink); margin: 0; }
.placeholder-note { font-size: 0.88rem; color: var(--ink-soft); margin: 0; max-width: 320px; }

/* ---------- Diagram / patent figures ---------- */
.diagram-figure {
  background: var(--warm-50);
  border: 1px solid var(--warm-300);
  padding: 22px;
}
.section-dark .diagram-figure { background: var(--charcoal-900); border-color: var(--charcoal-700); }
.diagram-figure figcaption {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--metal-700);
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--warm-200);
}
.section-dark .diagram-figure figcaption { color: var(--ink-on-dark-soft); border-top-color: var(--charcoal-700); }

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 4px 9px;
  border: 1px solid currentColor;
  font-weight: 600;
}
.tag-target { color: var(--rust-700); background: var(--rust-50); border-color: var(--rust-500); }
.tag-unverified { color: var(--metal-700); background: var(--warm-100); border-color: var(--metal-300); }
.tag-inventor { color: var(--ink); background: var(--warm-100); border-color: var(--warm-300); }
.tag-neutral { color: var(--metal-700); background: var(--warm-100); border-color: var(--warm-300); }
.tag-live { color: #4a5c34; background: #eef1e4; border-color: #9caf7c; }

.tech-diagram { width: 100%; height: auto; display: block; }
.patent-figure-img { width: 100%; background: var(--warm-50); padding: 10px; }

.chip-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 0; }
.eval-note {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--metal-700);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  margin-bottom: 6px;
  display: block;
}

/* ---------- Performance-target strip ---------- */
.stat-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid var(--charcoal-700);
}
@media (max-width: 760px) { .stat-strip { grid-template-columns: 1fr; } }
.stat-strip-item {
  padding: 30px 28px;
  border-right: 1px solid var(--charcoal-700);
}
.stat-strip-item:last-child { border-right: none; }
@media (max-width: 760px) {
  .stat-strip-item { border-right: none; border-bottom: 1px solid var(--charcoal-700); }
  .stat-strip-item:last-child { border-bottom: none; }
}
.stat-value {
  font-family: var(--font-display);
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--ink);
  display: block;
  margin-bottom: 6px;
  letter-spacing: -0.01em;
}
.stat-label { font-family: var(--font-display); font-weight: 600; color: var(--ink-soft); margin-bottom: 10px; display: block; font-size: 0.95rem; }
.stat-caveat { font-size: 0.8rem; color: var(--metal-700); margin: 0; }
.stat-strip .stat-value { color: var(--ink-on-dark); }
.stat-strip .stat-label { color: var(--ink-on-dark-soft); }
.stat-strip .stat-caveat { color: var(--metal-300); }
.stat-strip-foot {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-on-dark-soft);
  text-align: center;
  margin-top: 18px;
}

.stat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--warm-300); border: 1px solid var(--warm-300); }
@media (max-width: 760px) { .stat-grid { grid-template-columns: 1fr; } }
.stat-card { background: var(--warm-50); padding: 28px; }

/* ---------- Split layout ---------- */
.split { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 52px; align-items: center; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; } }
.split.reverse .split-media { order: -1; }
@media (max-width: 900px) { .split.reverse .split-media { order: 0; } }

/* ---------- Timeline ---------- */
.timeline { position: relative; margin-top: 8px; padding-left: 0; list-style: none; }
.timeline li {
  position: relative;
  padding: 0 0 32px 44px;
  border-left: 1px solid var(--warm-300);
  margin-left: 6px;
}
.section-dark .timeline li { border-left-color: var(--charcoal-700); }
.timeline li:last-child { border-color: transparent; padding-bottom: 0; }
.timeline li::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 2px;
  width: 10px; height: 10px;
  background: var(--rust-600);
  border: 2px solid var(--warm-50);
}
.section-dark .timeline li::before { border-color: var(--charcoal-950); }
.timeline h3 { margin-bottom: 6px; font-size: 1.08rem; }
.timeline p { margin-bottom: 0; }

/* ---------- Applications list ---------- */
.app-block {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 22px;
  padding: 32px 0;
  border-bottom: 1px solid var(--warm-300);
}
.app-block:last-child { border-bottom: none; }
.app-icon {
  width: 48px; height: 48px;
  background: var(--ink);
  color: var(--warm-50);
  display: flex;
  align-items: center;
  justify-content: center;
}
@media (max-width: 600px) {
  .app-block { grid-template-columns: 1fr; }
}

/* ---------- Callout / collaboration band ---------- */
.callout {
  background: var(--warm-50);
  border: 1px solid var(--warm-300);
  padding: 20px 24px;
  display: flex;
  gap: 14px;
  align-items: flex-start;
}
.section-dark .callout { background: var(--charcoal-900); border-color: var(--charcoal-700); }
.callout-icon { color: var(--rust-600); flex-shrink: 0; margin-top: 2px; }
.callout p { margin: 0; color: var(--ink-soft); font-size: 0.95rem; }
.section-dark .callout p { color: var(--ink-on-dark-soft); }
.callout strong { color: var(--ink); }
.section-dark .callout strong { color: var(--ink-on-dark); }

/* ---------- CTA band ---------- */
.cta-band {
  background: var(--charcoal-950);
  color: var(--ink-on-dark);
  padding: 56px 48px;
  text-align: center;
  position: relative;
}
.cta-band h2 { color: var(--ink-on-dark); }
.cta-band p { color: var(--ink-on-dark-soft); max-width: 560px; margin: 0 auto 30px; font-family: var(--font-serif); }
.cta-band .btn-actions { display: flex; justify-content: center; gap: 14px; flex-wrap: wrap; }

/* ---------- Forms ---------- */
.form-card {
  background: var(--warm-50);
  border: 1px solid var(--warm-300);
  padding: 40px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 640px) { .form-row { grid-template-columns: 1fr; } }
.field { margin-bottom: 20px; }
.field label {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--ink);
  margin-bottom: 7px;
}
.field .hint { font-size: 0.8rem; color: var(--metal-700); margin-top: 4px; }
.field input,
.field select,
.field textarea {
  width: 100%;
  font: inherit;
  font-family: var(--font-serif);
  padding: 12px 13px;
  border: 1.5px solid var(--warm-300);
  border-radius: var(--radius-sm);
  background: var(--warm-50);
  color: var(--ink);
}
.field input:focus,
.field select:focus,
.field textarea:focus {
  border-color: var(--rust-600);
  outline: 2px solid var(--rust-100);
}
.field textarea { min-height: 130px; resize: vertical; }
.required { color: var(--rust-600); }
fieldset { border: 1.5px solid var(--warm-300); border-radius: var(--radius-sm); padding: 14px 18px 6px; margin: 0 0 20px; }
fieldset legend { font-family: var(--font-display); font-weight: 600; font-size: 0.9rem; color: var(--ink); padding: 0 4px; }
.radio-row { display: flex; gap: 20px; flex-wrap: wrap; margin: 8px 0; }
.radio-row label { display: flex; align-items: center; gap: 6px; font-family: var(--font-serif); font-weight: 500; font-size: 0.95rem; color: var(--ink); }
.radio-row input { width: auto; }
.form-note { font-size: 0.85rem; color: var(--metal-700); margin-top: 18px; }
.section-dark .form-note { color: var(--ink-on-dark-soft); }
.form-success {
  display: none;
  background: #eef1e4;
  border: 1px solid #9caf7c;
  color: #46592f;
  padding: 16px 18px;
  margin-bottom: 24px;
  font-weight: 600;
  font-family: var(--font-display);
}
.form-success.is-visible { display: block; }

/* ---------- Contact info cards ---------- */
.contact-info-card {
  background: var(--charcoal-950);
  color: var(--ink-on-dark);
  padding: 34px;
}
.contact-info-card h3 { color: var(--ink-on-dark); }
.contact-info-card a { color: var(--rust-400); }
.contact-list { list-style: none; padding: 0; margin: 18px 0 0; }
.contact-list li { padding: 12px 0; border-top: 1px solid var(--charcoal-700); display: flex; gap: 10px; }
.contact-list li:first-child { border-top: none; }

/* ---------- Illustrative 3D linkage model ---------- */
.linkage-3d {
  position: relative;
  aspect-ratio: 4 / 3;
  background: var(--charcoal-900);
  overflow: hidden;
}
.linkage-3d canvas {
  position: absolute;
  inset: 0;
  width: 100% !important;
  height: 100% !important;
  display: block;
}
.linkage-3d-fallback {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  text-align: center;
  color: var(--ink-on-dark-soft);
  padding: 20px;
}
.linkage-3d.has-canvas .linkage-3d-fallback { display: none; }

/* ---------- Patent image crossfade ---------- */
.patent-crossfade {
  position: relative;
  aspect-ratio: 4 / 3;
  background: var(--warm-50);
  overflow: hidden;
}
.patent-crossfade img {
  position: absolute;
  inset: 0;
  margin: auto;
  max-width: 80%;
  max-height: 80%;
  object-fit: contain;
  opacity: 0;
}
.patent-crossfade img:first-child { opacity: 1; }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--charcoal-950);
  color: var(--ink-on-dark-soft);
  padding: 60px 0 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px;
  padding-bottom: 36px;
  border-bottom: 1px solid var(--charcoal-700);
}
@media (max-width: 760px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-grid h4 {
  font-family: var(--font-mono);
  color: var(--ink-on-dark);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 16px;
  font-weight: 600;
}
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { margin-bottom: 11px; }
.footer-grid a { color: var(--ink-on-dark-soft); }
.footer-grid a:hover { color: var(--ink-on-dark); }
.footer-brand { font-family: var(--font-display); color: var(--ink-on-dark); font-weight: 800; margin-bottom: 10px; display: block; font-size: 1.05rem; }
.footer-tagline { font-size: 0.9rem; color: var(--ink-on-dark-soft); max-width: 300px; font-family: var(--font-serif); }
.footer-disclaimer {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--metal-500);
  max-width: 900px;
  margin: 28px 0 0;
}
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--metal-500);
}
.footer-bottom a { color: var(--metal-300); }

/* ---------- Misc utility ---------- */
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.text-center { text-align: center; }
.icon-list { list-style: none; padding: 0; margin: 0; }
.icon-list li { display: flex; gap: 10px; align-items: flex-start; margin-bottom: 12px; color: var(--ink-soft); }
.icon-list li svg { flex-shrink: 0; margin-top: 3px; color: var(--rust-600); }

.proof-list {
  max-width: 760px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px 32px;
}
@media (max-width: 640px) { .proof-list { grid-template-columns: 1fr; } }

.disclosure-box {
  background: var(--warm-100);
  border-left: 3px solid var(--metal-500);
  padding: 18px 22px;
  font-size: 0.92rem;
  color: var(--ink-soft);
  margin: 28px 0;
}
.section-dark .disclosure-box { background: var(--charcoal-900); border-left-color: var(--metal-500); color: var(--ink-on-dark-soft); }
.disclosure-box strong { color: var(--ink); }
.section-dark .disclosure-box strong { color: var(--ink-on-dark); }

.code-snippet {
  background: var(--charcoal-950);
  color: var(--metal-300);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.6;
  padding: 16px 18px;
  overflow-x: auto;
  text-align: left;
  margin: 14px 0 0;
  width: 100%;
}
.code-snippet code { color: inherit; white-space: pre; }