/* ==========================================================================
   Cornerstone — Industrial Clarity design system
   Implements website_design_guide.md: Industrial Ink / Plan White palette,
   Barlow Condensed + Inter + IBM Plex Mono, 8px spacing tokens, dark
   hero/loop/trust/CTA sections with construction-grid background motifs.
   ========================================================================== */

/* --- Fonts (self-hosted, latin subsets) --------------------------------- */

@font-face {
  font-family: "Barlow Condensed"; font-style: normal; font-weight: 600; font-display: swap;
  src: url("../fonts/barlow-condensed-600.woff2") format("woff2");
}
@font-face {
  font-family: "Barlow Condensed"; font-style: normal; font-weight: 700; font-display: swap;
  src: url("../fonts/barlow-condensed-700.woff2") format("woff2");
}
@font-face {
  font-family: "Inter"; font-style: normal; font-weight: 400; font-display: swap;
  src: url("../fonts/inter-400.woff2") format("woff2");
}
@font-face {
  font-family: "Inter"; font-style: normal; font-weight: 500; font-display: swap;
  src: url("../fonts/inter-500.woff2") format("woff2");
}
@font-face {
  font-family: "Inter"; font-style: normal; font-weight: 600; font-display: swap;
  src: url("../fonts/inter-600.woff2") format("woff2");
}
@font-face {
  font-family: "Inter"; font-style: normal; font-weight: 700; font-display: swap;
  src: url("../fonts/inter-700.woff2") format("woff2");
}
@font-face {
  font-family: "IBM Plex Mono"; font-style: normal; font-weight: 400; font-display: swap;
  src: url("../fonts/ibm-plex-mono-400.woff2") format("woff2");
}

/* --- Design tokens (guide §22) ------------------------------------------ */

:root {
  --color-ink: #0f1722;
  --color-ink-deep: #102a3a;
  --color-slate: #334155;
  --color-field-gray: #64748b;
  --color-line: #cbd5e1;
  --color-mist: #e2e8f0;
  --color-plan-white: #f8fafc;
  --color-white: #ffffff;

  --color-primary: #0ea5e9;        /* accent on dark surfaces, data series */
  /* Interactive fills and text links on light surfaces use a deeper blue:
     white text on #0ea5e9 fails WCAG AA (§21), #0369a1 passes. */
  --color-primary-deep: #0369a1;
  --color-primary-deep-hover: #075985;
  --color-primary-tint: #e0f2fe;

  --color-warning: #f59e0b;
  --color-warning-text: #92600a;
  --color-warning-bg: #fef3d8;
  --color-danger: #ef4444;
  --color-danger-text: #b42328;
  --color-danger-bg: #fde6e5;
  --color-success: #10b981;
  --color-success-text: #086b4f;
  --color-success-bg: #dcf5ec;

  --font-display: "Barlow Condensed", "Arial Narrow", sans-serif;
  --font-body: "Inter", -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "IBM Plex Mono", Consolas, monospace;

  --radius-small: 4px;
  --radius-medium: 6px;

  --container-max: 1280px;
  --content-reading: 720px;

  --space-1: 4px;  --space-2: 8px;   --space-3: 12px; --space-4: 16px;
  --space-5: 24px; --space-6: 32px;  --space-7: 48px; --space-8: 64px;
  --space-9: 80px; --space-10: 96px; --space-11: 128px;

  /* dark-surface text roles (§5) */
  --dark-text: #ffffff;
  --dark-text-secondary: #cbd5e1;
  --dark-text-muted: #94a3b8;
  --dark-border: rgba(255, 255, 255, 0.15);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-ink);
  background: var(--color-plan-white);
}

img { max-width: 100%; height: auto; }

/* --- Type scale (guide §7) ---------------------------------------------- */

h1, h2 {
  font-family: var(--font-display);
  color: inherit;
  letter-spacing: 0.005em;
}
h1 { font-size: clamp(44px, 5vw, 64px); line-height: 0.98; font-weight: 700; margin: 0 0 var(--space-5); }
.page-hero h1 { font-size: clamp(40px, 4.5vw, 52px); line-height: 1; }
h2 { font-size: clamp(32px, 3.5vw, 40px); line-height: 1.05; font-weight: 600; margin: 0 0 var(--space-4); }
h3 { font-family: var(--font-body); font-size: 20px; line-height: 1.25; font-weight: 600; margin: 0 0 var(--space-2); }

p { margin: 0 0 var(--space-4); }
ul, ol { margin: 0 0 var(--space-4); padding-left: 22px; }
a { color: var(--color-primary-deep); }
a:hover { color: var(--color-primary-deep-hover); }

.lead { font-size: 20px; line-height: 1.55; color: var(--color-slate); }

:focus-visible { outline: 2px solid var(--color-primary-deep); outline-offset: 2px; }
.section-dark :focus-visible, .section-deep :focus-visible,
.site-header :focus-visible, .site-footer :focus-visible {
  outline-color: var(--color-primary);
}

.container { max-width: var(--container-max); margin: 0 auto; padding: 0 var(--space-7); }
.container.narrow { max-width: var(--content-reading); }
.center { text-align: center; }
@media (max-width: 768px) { .container { padding: 0 20px; } }

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

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--color-primary-deep); color: #fff;
  padding: var(--space-3) var(--space-4); z-index: 100;
}
.skip-link:focus { left: 0; color: #fff; }

/* --- Construction-grid background motif (guide §16) ---------------------- */

.bg-grid {
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 48px 48px;
}
@media (max-width: 768px) { .bg-grid { background-image: none; } }

/* --- Header (guide §11): Industrial Ink, 72px, white nav ----------------- */

.site-header {
  background: var(--color-ink);
  border-bottom: 1px solid var(--dark-border);
  position: sticky; top: 0; z-index: 50;
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--space-5); min-height: 72px; flex-wrap: wrap;
  padding-top: var(--space-2); padding-bottom: var(--space-2);
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.brand-mark {
  width: 20px; height: 20px;
  background: var(--color-primary);
  clip-path: polygon(0 100%, 0 35%, 35% 35%, 35% 0, 100% 0, 100% 100%);
}
.brand-name {
  font-family: var(--font-display); font-weight: 700; font-size: 24px;
  letter-spacing: 0.02em; color: var(--dark-text); text-transform: uppercase;
}

.nav-toggle {
  display: none;
  background: none; border: 1px solid var(--dark-border); border-radius: var(--radius-small);
  font: inherit; font-weight: 500; color: var(--dark-text);
  padding: 10px 16px; min-height: 44px; cursor: pointer;
  align-items: center; gap: var(--space-2);
}
.nav-toggle-bar, .nav-toggle-bar::before, .nav-toggle-bar::after {
  display: block; width: 18px; height: 2px; background: var(--dark-text); content: "";
}
.nav-toggle-bar { position: relative; }
.nav-toggle-bar::before { position: absolute; top: -5px; }
.nav-toggle-bar::after { position: absolute; top: 5px; }

.site-nav ul {
  display: flex; align-items: center; gap: var(--space-5);
  list-style: none; margin: 0; padding: 0; flex-wrap: wrap;
}
.site-nav a { text-decoration: none; color: var(--dark-text-secondary); font-weight: 500; font-size: 15px; }
.site-nav a:hover { color: var(--dark-text); }
.site-nav a[aria-current="page"] {
  color: var(--dark-text);
  border-bottom: 2px solid var(--color-primary);
  padding-bottom: 2px;
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }
  .site-nav { display: none; }
  .site-nav.open {
    display: block;
    position: fixed; top: 72px; left: 0; right: 0; bottom: 0;
    background: var(--color-ink);
    overflow-y: auto; z-index: 60;
    padding: var(--space-5) 20px var(--space-8);
  }
  .site-nav ul { flex-direction: column; align-items: stretch; gap: 0; }
  .site-nav li { border-bottom: 1px solid var(--dark-border); }
  .site-nav a {
    display: block; padding: var(--space-4) var(--space-1);
    font-family: var(--font-display); font-size: 28px; font-weight: 600;
    text-transform: none;
  }
  .site-nav a[aria-current="page"] {
    border-bottom: none; border-left: 3px solid var(--color-primary); padding-left: var(--space-3);
  }
  .nav-cta { margin-top: var(--space-5); text-align: center; }
  .site-nav li:has(.nav-cta), .site-nav li:last-child { border-bottom: none; }
}

/* --- Buttons (guide §12) ------------------------------------------------- */

.btn {
  display: inline-block;
  padding: 12px 24px; min-height: 48px;
  border-radius: var(--radius-small);
  border: 1px solid transparent;
  font-family: var(--font-body); font-weight: 600; font-size: 16px; line-height: 1.4;
  text-decoration: none; cursor: pointer;
  transition: background-color 180ms ease-out, color 180ms ease-out, border-color 180ms ease-out;
}
.btn-primary { background: var(--color-primary-deep); color: #fff; }
.btn-primary:hover { background: var(--color-primary-deep-hover); color: #fff; }

/* On dark surfaces the primary button uses Primary Blue with Ink text (AA). */
.section-dark .btn-primary, .section-deep .btn-primary, .site-header .btn-primary {
  background: var(--color-primary); color: var(--color-ink);
}
.section-dark .btn-primary:hover, .section-deep .btn-primary:hover, .site-header .btn-primary:hover {
  background: #38bdf8; color: var(--color-ink);
}

.btn-secondary { background: transparent; border-color: var(--color-ink); color: var(--color-ink); }
.btn-secondary:hover { background: var(--color-mist); color: var(--color-ink); }

/* Secondary button on dark: transparent with white border (guide §12). */
.section-dark .btn-secondary, .section-deep .btn-secondary {
  border-color: rgba(255, 255, 255, 0.6); color: var(--dark-text); background: transparent;
}
.section-dark .btn-secondary:hover, .section-deep .btn-secondary:hover {
  background: var(--color-white); color: var(--color-ink);
}

.btn[disabled] { opacity: 0.45; cursor: not-allowed; }
.nav-cta { padding: 10px 20px; min-height: 44px; }

.cta-row { display: flex; gap: var(--space-4); flex-wrap: wrap; margin-top: var(--space-6); }
.cta-row.center { justify-content: center; }
@media (max-width: 640px) { .cta-row .btn { width: 100%; text-align: center; } }

/* --- Sections (guide §9–10) ---------------------------------------------- */

.section { padding: var(--space-10) 0; }
.section-alt { background: var(--color-mist); }
.section-dark { background: var(--color-ink); color: var(--dark-text); }
.section-deep { background: var(--color-ink-deep); color: var(--dark-text); }
.section-dark p, .section-deep p { color: var(--dark-text-secondary); }
.section-dark h2, .section-deep h2, .section-dark h3, .section-deep h3 { color: var(--dark-text); }
.section-dark .lead, .section-deep .lead { color: var(--dark-text-secondary); }
.section-cta { padding: var(--space-11) 0; }
.section-heading { margin-bottom: var(--space-6); }
@media (max-width: 768px) {
  .section { padding: var(--space-8) 0; }
  .section-cta { padding: var(--space-9) 0; }
}

.page-hero {
  background: var(--color-ink); color: var(--dark-text);
  padding: var(--space-9) 0 var(--space-8);
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 48px 48px;
}
@media (max-width: 768px) { .page-hero { background-image: none; } }
.page-hero .lead { color: var(--dark-text-secondary); }
.page-hero .visual-disclosure { color: var(--dark-text-muted); }
.page-hero a:not(.btn) { color: var(--color-primary); }
@media (max-width: 768px) { .page-hero { padding: var(--space-8) 0 var(--space-7); } }

.kicker {
  font-family: var(--font-body);
  text-transform: uppercase; letter-spacing: 0.1em;
  font-size: 12px; font-weight: 600; color: var(--color-primary-deep);
  margin-bottom: var(--space-3);
}
.section-dark .kicker, .section-deep .kicker, .page-hero .kicker { color: var(--color-primary); }

/* --- Hero (guide §10.1, §23): dark split layout --------------------------- */

/* Hero photograph with left-to-right Industrial Ink overlay (guide §15,
   image_placement.md §2.1): ~75%+ ink over the text area, lighter over the
   building. Overlay lives in CSS, not baked into the image. */
.hero {
  background-color: var(--color-ink); color: var(--dark-text);
  background-image:
    linear-gradient(to right,
      rgba(15, 23, 34, 0.94) 0%,
      rgba(15, 23, 34, 0.78) 45%,
      rgba(15, 23, 34, 0.35) 100%),
    url("../images/production/home/hero/home_hero-construction_desktop_v01.webp");
  background-position: center right;
  background-size: cover;
  padding: var(--space-11) 0;
  min-height: 680px; display: flex; align-items: center;
}
@media (max-width: 768px) {
  .hero {
    background-image:
      linear-gradient(rgba(15, 23, 34, 0.86), rgba(15, 23, 34, 0.78)),
      url("../images/production/home/hero/home_hero-construction_mobile_v01.webp");
    background-position: 62% center;
  }
}
.hero .lead { color: var(--dark-text-secondary); }
.hero-grid {
  display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: var(--space-8); align-items: center; width: 100%;
}
@media (max-width: 900px) {
  .hero { min-height: 0; padding: var(--space-9) 0; }
  .hero-grid { grid-template-columns: 1fr; gap: var(--space-6); }
}

/* --- Panels: practical project-control interfaces (guide §2.3, §13) ------ */

.panel {
  background: var(--color-white);
  color: var(--color-ink);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-medium);
  text-align: left;
}
.section-dark .panel, .section-deep .panel, .hero .panel { border-color: var(--dark-border); }
.panel-header {
  display: flex; align-items: center; justify-content: space-between; gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-line);
  background: var(--color-plan-white);
  border-radius: var(--radius-medium) var(--radius-medium) 0 0;
}
.panel-title { font-weight: 600; font-size: 14px; }
.panel-section { padding: var(--space-4); border-bottom: 1px solid var(--color-mist); }
.panel-section:last-of-type { border-bottom: none; }
.panel-label {
  font-size: 11px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.08em; color: var(--color-field-gray); margin: 0 0 var(--space-3);
}
.panel-footnote {
  font-size: 12px; color: var(--color-field-gray);
  padding: var(--space-3) var(--space-4); margin: 0; border-top: 1px solid var(--color-mist);
}

/* Status tags: label + color, never color alone (guide §5) */
.tag {
  display: inline-block; padding: 2px 8px;
  font-size: 11px; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase;
  border-radius: var(--radius-small); border: 1px solid transparent;
  vertical-align: middle;
}
.tag-risk { background: var(--color-danger-bg); color: var(--color-danger-text); border-color: var(--color-danger); }
.tag-caution { background: var(--color-warning-bg); color: var(--color-warning-text); border-color: var(--color-warning); }
.tag-good { background: var(--color-success-bg); color: var(--color-success-text); border-color: var(--color-success); }
.tag-recommended { background: var(--color-primary-tint); color: var(--color-primary-deep); border-color: var(--color-primary-deep); }

.observation-list { list-style: none; padding: 0; margin: 0; }
.observation-list li {
  display: flex; gap: var(--space-3); align-items: baseline;
  padding: 6px 0; font-size: 14px;
  border-bottom: 1px dashed var(--color-mist);
}
.observation-list li:last-child { border-bottom: none; }
.obs-time { font-family: var(--font-mono); font-size: 12px; color: var(--color-field-gray); white-space: nowrap; }

.action-list { list-style: none; padding: 0; margin: 0; display: grid; gap: var(--space-4); }
.action-row { display: grid; gap: var(--space-1); }
.action-name { font-weight: 600; font-size: 14px; }
.action-est { font-size: 13px; color: var(--color-slate); }
.action-recommended {
  border-left: 3px solid var(--color-primary-deep);
  padding-left: var(--space-3); margin-left: calc(-1 * var(--space-3));
}

/* Confidence intervals: band + midpoint tick (guide §14) */
.range-bar {
  position: relative; display: block; height: 10px;
  background: var(--color-mist); border-radius: 2px; overflow: hidden;
}
.range { position: absolute; top: 0; bottom: 0; background: var(--color-primary-tint); border: 1px solid var(--color-primary); }
.range-mid { position: absolute; top: 0; bottom: 0; width: 2px; background: var(--color-primary-deep); }

.stat-list { list-style: none; margin: 0; padding: var(--space-2) 0; }
.stat-list li {
  display: flex; flex-wrap: wrap; gap: var(--space-2); align-items: baseline;
  padding: 8px var(--space-4); font-size: 14px;
  border-bottom: 1px dashed var(--color-mist);
}
.stat-list li:last-child { border-bottom: none; }
.stat-label { color: var(--color-field-gray); min-width: 172px; }
.stat-value { font-weight: 600; }

.visual-disclosure {
  font-size: 13px; color: var(--color-field-gray);
  font-style: italic; margin-top: var(--space-3);
}
.section-dark .visual-disclosure, .hero .visual-disclosure { color: var(--dark-text-muted); }

/* --- Cards (guide §13) ---------------------------------------------------- */

.card-grid { display: grid; gap: var(--space-5); }
.card-grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card-grid.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card-grid.four { grid-template-columns: repeat(4, minmax(0, 1fr)); }
@media (max-width: 1000px) {
  .card-grid.three, .card-grid.four { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .card-grid.two, .card-grid.three, .card-grid.four { grid-template-columns: 1fr; }
}

.card {
  background: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-medium);
  padding: var(--space-6);
}
.section-dark .card, .section-deep .card {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--dark-border);
}
.card-kicker {
  font-size: 11px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.08em; color: var(--color-field-gray); margin: var(--space-3) 0 var(--space-1);
}
.card-kicker:first-child { margin-top: 0; }
.card-title { font-weight: 600; font-size: 18px; margin-bottom: var(--space-2); }
.card-emphasis { border-top: 3px solid var(--color-primary-deep); }
.card-link { display: block; text-decoration: none; color: inherit; }
.card-link:hover { border-color: var(--color-primary-deep); color: inherit; }
.card-cta { color: var(--color-primary-deep); font-weight: 600; }
.card-link:hover .card-cta { text-decoration: underline; }
.card-note { font-size: 13px; font-style: italic; color: var(--color-field-gray); margin-bottom: 0; }

.ladder .card p:last-child { color: var(--color-slate); }

/* --- Product loop: dark five-step process (guide §23) --------------------- */

.loop-grid {
  display: grid; grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: var(--space-4); list-style: none; padding: 0; margin: var(--space-7) 0 0;
}
@media (max-width: 1000px) { .loop-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 640px) { .loop-grid { grid-template-columns: 1fr; } }
.loop-step {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--dark-border);
  border-radius: var(--radius-medium); padding: var(--space-5);
}
.loop-step h3 { color: var(--dark-text); }
.loop-step p { font-size: 14px; margin-bottom: 0; color: var(--dark-text-secondary); }

.loop-num, .step-num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; margin-bottom: var(--space-3);
  background: var(--color-primary); color: var(--color-ink);
  font-family: var(--font-display); font-weight: 700; font-size: 18px;
  border-radius: var(--radius-small);
}

/* --- Feature blocks (alternating sections, guide §10.2) ------------------- */

.feature-block {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-8); align-items: start;
  padding: var(--space-6) 0; border-top: 1px solid var(--color-line);
}
.feature-block:first-child { border-top: none; padding-top: 0; }
@media (max-width: 900px) { .feature-block { grid-template-columns: 1fr; gap: var(--space-5); } }

/* --- Steps ---------------------------------------------------------------- */

.step-list { list-style: none; padding: 0; margin: 0; }
.step { padding: var(--space-6) 0; border-top: 1px solid var(--color-line); }
.step:first-child { border-top: none; padding-top: 0; }
.step h2, .scenario-step h2 { display: flex; align-items: center; gap: var(--space-3); }
.step h2 .step-num, .scenario-step h2 .step-num { margin-bottom: 0; flex-shrink: 0; }

.scenario-step { padding: var(--space-6) 0; border-top: 1px solid var(--color-line); }
.scenario-step:first-of-type { border-top: none; padding-top: 0; }
.scenario-controls { margin-bottom: var(--space-6); }
.scenario-progress { font-family: var(--font-mono); font-size: 13px; color: var(--color-field-gray); margin-bottom: var(--space-1); }
.scenario-controls .cta-row { margin-top: var(--space-1); }

/* --- Tables (guide §14) --------------------------------------------------- */

.table-wrap { overflow-x: auto; margin: var(--space-4) 0; }
.compare-table {
  width: 100%; border-collapse: collapse;
  background: var(--color-white); border: 1px solid var(--color-line);
  font-size: 15px;
}
.compare-table th, .compare-table td {
  text-align: left; padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-mist);
  vertical-align: top;
}
.compare-table thead th {
  background: var(--color-mist);
  font-size: 12px; text-transform: uppercase; letter-spacing: 0.07em;
  border-bottom: 1px solid var(--color-line);
}
.compare-table tbody th { font-weight: 600; }
.row-recommended th, .row-recommended td { background: var(--color-primary-tint); }
.row-recommended th::after {
  content: "Recommended";
  display: inline-block; margin-left: var(--space-2);
  font-size: 10px; font-weight: 600; letter-spacing: 0.05em; text-transform: uppercase;
  color: var(--color-primary-deep); border: 1px solid var(--color-primary-deep);
  border-radius: var(--radius-small); padding: 1px 6px;
  vertical-align: middle;
}

/* --- Chips / principles / quotes ------------------------------------------ */

.chip-grid {
  display: flex; flex-wrap: wrap; gap: var(--space-3);
  list-style: none; padding: 0; margin: var(--space-6) 0 0;
}
.chip-grid li {
  background: var(--color-white); border: 1px solid var(--color-line);
  border-radius: var(--radius-small); padding: var(--space-2) var(--space-4);
  font-size: 14px; font-weight: 500;
}
.section-alt .chip-grid li { border-color: var(--color-line); }

.principle-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-5); margin: var(--space-6) 0 0;
}
.principle {
  background: var(--color-white); border: 1px solid var(--color-line);
  border-left: 3px solid var(--color-primary-deep);
  border-radius: var(--radius-small); padding: var(--space-5);
}
.section-dark .principle, .section-deep .principle {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--dark-border);
  border-left: 3px solid var(--color-primary);
}
.principle dt { font-weight: 600; margin-bottom: var(--space-2); }
.section-dark .principle dt, .section-deep .principle dt { color: var(--dark-text); }
.principle dd { margin: 0; font-size: 15px; color: var(--color-slate); }
.section-dark .principle dd, .section-deep .principle dd { color: var(--dark-text-secondary); }

.pull-quote {
  margin: 0; padding: 0 0 0 var(--space-5);
  border-left: 3px solid var(--color-primary-deep);
}
.pull-quote p {
  font-family: var(--font-display);
  font-size: clamp(26px, 3vw, 30px); line-height: 1.1; font-weight: 600;
  margin-bottom: var(--space-2); color: var(--color-ink);
}
.pull-quote footer { color: var(--color-field-gray); font-size: 14px; }

/* --- Forms (guide §18) ----------------------------------------------------- */

.form-grid {
  display: grid; grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: var(--space-8); align-items: start;
}
@media (max-width: 900px) { .form-grid { grid-template-columns: 1fr; } }

.demo-form {
  background: var(--color-white); border: 1px solid var(--color-line);
  border-radius: var(--radius-medium); padding: var(--space-6);
}
.demo-form .field { margin-bottom: var(--space-5); }
.demo-form label { display: block; font-weight: 600; font-size: 14px; margin-bottom: var(--space-2); }
.req { color: var(--color-danger-text); }
.demo-form input, .demo-form select, .demo-form textarea {
  width: 100%; min-height: 48px; padding: var(--space-3) var(--space-3);
  font: inherit; color: var(--color-ink);
  background: var(--color-white); border: 1px solid var(--color-field-gray);
  border-radius: var(--radius-small);
}
.demo-form textarea { resize: vertical; }
.form-note { font-size: 13px; color: var(--color-field-gray); margin-top: var(--space-4); }
@media (max-width: 640px) { .demo-form .btn { width: 100%; text-align: center; } }

.form-aside {
  background: var(--color-mist); border: 1px solid var(--color-line);
  border-radius: var(--radius-medium); padding: var(--space-6);
}

.flash { padding: var(--space-3) var(--space-4); border-radius: var(--radius-small); margin: var(--space-4) 0 0; font-weight: 500; }
.flash-error { background: var(--color-danger-bg); color: var(--color-danger-text); border: 1px solid var(--color-danger); }

/* --- Illustrative figures (generated concept graphics, always labeled) ---- */

.figure { margin: var(--space-6) 0 0; }
.figure img {
  display: block; width: 100%;
  background: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-medium);
}
.figure figcaption {
  font-size: 13px; color: var(--color-field-gray);
  font-style: italic; margin-top: var(--space-2);
}
.section-dark .figure figcaption, .section-deep .figure figcaption { color: var(--dark-text-muted); }
.figure-narrow { max-width: 560px; }
/* Wide landscape figures: capped below full container so they don't dominate. */
.figure-wide { max-width: 1000px; margin-left: auto; margin-right: auto; }
/* Portrait figures: never full container width — cap and center. */
.figure-portrait { max-width: 460px; margin-left: auto; margin-right: auto; }

.decision-card .card-illustration {
  display: block; width: 100%;
  border: 1px solid var(--color-mist); border-radius: var(--radius-small);
  margin-bottom: var(--space-4); background: var(--color-white);
}

.insight-card .card-thumb {
  display: block; width: 100%;
  border: 1px solid var(--color-line); border-radius: var(--radius-small);
  margin-bottom: var(--space-4);
}

.pilot-list { list-style: none; padding: 0; margin: var(--space-4) 0; display: grid; gap: var(--space-3); }
.pilot-list li { display: flex; align-items: center; gap: var(--space-3); font-weight: 500; }
.pilot-list img {
  width: 52px; height: 52px; object-fit: cover; flex-shrink: 0;
  border: 1px solid var(--color-line); border-radius: var(--radius-small);
  background: var(--color-white);
}

/* --- Photography bands ---------------------------------------------------- */

.photo-band { margin: 0; background: var(--color-ink); }
.photo-band img { display: block; width: 100%; max-height: 560px; object-fit: cover; }

/* --- Footer (guide §10.3): Industrial Ink -------------------------------- */

.site-footer {
  background: var(--color-ink); color: var(--dark-text-secondary);
  padding: var(--space-9) 0 var(--space-5);
  font-size: 15px;
}
.footer-inner {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-6);
}
@media (max-width: 900px) { .footer-inner { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .footer-inner { grid-template-columns: 1fr; } }
.site-footer .brand-name { color: var(--dark-text); }
.footer-brand p { margin-top: var(--space-3); color: var(--dark-text-muted); }
.footer-heading {
  font-size: 12px; text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--dark-text-muted); margin: 0 0 var(--space-3); font-weight: 600;
}
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: var(--space-2); }
.site-footer a { color: var(--dark-text-secondary); text-decoration: none; }
.site-footer a:hover { color: var(--dark-text); text-decoration: underline; }
.footer-legal {
  margin-top: var(--space-8); padding-top: var(--space-5);
  border-top: 1px solid var(--dark-border);
  font-size: 13px; color: var(--dark-text-muted);
}