/* ============================================================
   AART AERO — design system
   Concept: the maintenance logbook. Warm paper surfaces, hangar
   navy ink, safety-orange accent, mono spec labels.
   ============================================================ */

:root {
  /* Type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 5rem);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Surfaces — warm logbook paper */
  --color-bg: #f4f2ed;
  --color-surface: #faf9f6;
  --color-surface-offset: #ece9e2;
  --color-surface-dynamic: #e2ded5;
  --color-divider: #dcd8cf;

  /* Ink — hangar navy */
  --color-text: #1c2532;
  --color-text-muted: #5c6470;
  --color-text-faint: #98918a;
  --color-text-inverse: #f6f4ef;

  /* Dark section surfaces */
  --color-dark: #151d29;
  --color-dark-2: #1a2433;
  --color-dark-text: #e9e7e1;
  --color-dark-muted: #9aa1ad;

  /* Accent — safety orange */
  --color-primary: #b84710;
  --color-primary-hover: #9a3a0c;
  --color-primary-soft: #f3e2d6;
  --color-steel: #3e5a74;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-sm: 0 1px 2px oklch(0.2 0.02 250 / 0.06);
  --shadow-md: 0 4px 12px oklch(0.2 0.02 250 / 0.08);
  --shadow-lg: 0 12px 32px oklch(0.2 0.02 250 / 0.12);

  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1180px;

  --font-display: 'Cabinet Grotesk', 'Avenir Next', 'Helvetica Neue', sans-serif;
  --font-body: 'Satoshi', 'Inter', 'Helvetica Neue', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Menlo, monospace;
}

/* ---------- Shared ---------- */

.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container-narrow {
  max-width: var(--content-narrow);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.mono-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  z-index: 100;
  background: var(--color-primary);
  color: #fff;
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
}
.skip-link:focus {
  top: var(--space-3);
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: oklch(from var(--color-bg) l c h / 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition:
    transform 0.3s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.site-header.is-scrolled {
  border-bottom-color: var(--color-divider);
}
.site-header.is-hidden {
  transform: translateY(-100%);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 72px;
}

.wordmark {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: var(--color-text);
}
.wordmark strong {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: var(--text-lg);
  letter-spacing: 0.02em;
  line-height: 1.1;
}
.wordmark span {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.site-nav {
  display: none;
  align-items: center;
  gap: var(--space-8);
}
.site-nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
}
.site-nav a:hover {
  color: var(--color-text);
}

.header-cta {
  display: none;
}
.site-header .btn.header-cta {
  display: none;
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  color: var(--color-text);
}

.mobile-nav {
  display: none;
  flex-direction: column;
  padding: var(--space-2) var(--space-6) var(--space-6);
  border-top: 1px solid var(--color-divider);
}
.mobile-nav.is-open {
  display: flex;
}
.mobile-nav a {
  padding: var(--space-4) 0;
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--color-text);
  text-decoration: none;
  border-bottom: 1px solid var(--color-divider);
}
.mobile-nav a:last-child {
  border-bottom: none;
}

@media (min-width: 900px) {
  .site-nav {
    display: inline-flex;
  }
  .site-header .btn.header-cta {
    display: inline-flex;
  }
  .nav-toggle,
  .mobile-nav {
    display: none;
  }
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: 48px;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--color-primary-hover);
}
.btn-ghost {
  border-color: oklch(from #fff l c h / 0.35);
  color: #fff;
}
.btn-ghost:hover {
  border-color: #fff;
  background: oklch(from #fff l c h / 0.08);
}
.btn-outline {
  border-color: oklch(from var(--color-text) l c h / 0.25);
  color: var(--color-text);
}
.btn-outline:hover {
  border-color: var(--color-text);
  background: var(--color-surface);
}
.btn:active {
  transform: translateY(1px);
}

/* ---------- Hero ---------- */

.hero {
  position: relative;
  background: var(--color-dark);
  color: var(--color-dark-text);
  overflow: hidden;
}
.hero-media {
  position: absolute;
  inset: 0;
}
.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.55;
}
.hero-scrim {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(
      90deg,
      var(--color-dark) 0%,
      oklch(from var(--color-dark) l c h / 0.85) 42%,
      oklch(from var(--color-dark) l c h / 0.25) 100%
    ),
    linear-gradient(0deg, var(--color-dark) 0%, transparent 32%);
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(oklch(from #fff l c h / 0.045) 1px, transparent 1px),
    linear-gradient(90deg, oklch(from #fff l c h / 0.045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: linear-gradient(180deg, transparent 30%, black 100%);
}
.hero-inner {
  position: relative;
  padding-block: clamp(var(--space-16), 10vw, var(--space-32)) var(--space-16);
  max-width: 720px;
}
.hero-eyebrow {
  color: #e8a063;
  margin-bottom: var(--space-6);
  display: block;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 800;
  letter-spacing: -0.015em;
  margin-bottom: var(--space-6);
  color: #fff;
}
.hero-sub {
  font-size: var(--text-lg);
  line-height: 1.55;
  color: var(--color-dark-muted);
  max-width: 54ch;
  margin-bottom: var(--space-10);
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.hero-spec {
  position: relative;
  border-top: 1px solid oklch(from #fff l c h / 0.14);
}
.hero-spec-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4) var(--space-8);
  padding-block: var(--space-6);
}
@media (min-width: 820px) {
  .hero-spec-row {
    grid-template-columns: repeat(4, 1fr);
  }
}
.hero-spec-item dt {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #e8a063;
  margin-bottom: var(--space-2);
}
.hero-spec-item dd {
  font-size: var(--text-sm);
  color: var(--color-dark-muted);
}

/* ---------- Sections ---------- */

.section {
  padding-block: clamp(var(--space-12), 7vw, var(--space-24));
}
.section-tight {
  padding-block: clamp(var(--space-10), 5vw, var(--space-16));
}

.section-head {
  max-width: 640px;
  margin-bottom: var(--space-12);
}
.section-head .mono-label {
  color: var(--color-primary);
  display: block;
  margin-bottom: var(--space-4);
}
.section-head h2 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-4);
}
.section-head p {
  color: var(--color-text-muted);
}

/* ---------- Services ---------- */

.service-feature {
  display: grid;
  gap: var(--space-8);
  background: var(--color-surface);
  border: 1px solid oklch(from var(--color-text) l c h / 0.1);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: var(--space-8);
}
@media (min-width: 920px) {
  .service-feature {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 0;
  }
  .service-feature-flip {
    grid-template-columns: 0.85fr 1.15fr;
  }
}
.service-feature-body {
  padding: clamp(var(--space-6), 4vw, var(--space-12));
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.service-num {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
  letter-spacing: 0.1em;
  display: block;
  margin-bottom: var(--space-4);
}
.service-feature-body h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-4);
}
.service-feature-body > p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}
.service-media {
  min-height: 280px;
}
.service-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.service-feature-flip .service-media {
  order: -1;
}

.service-list {
  display: grid;
  gap: var(--space-3) var(--space-8);
}
@media (min-width: 640px) {
  .service-list {
    grid-template-columns: 1fr 1fr;
  }
}
.service-list li {
  display: flex;
  gap: var(--space-3);
  font-size: var(--text-sm);
  font-weight: 500;
  align-items: baseline;
}
.service-list li::before {
  content: '—';
  color: var(--color-primary);
  flex: none;
}

.service-cards {
  display: grid;
  gap: var(--space-6);
}
@media (min-width: 820px) {
  .service-cards {
    grid-template-columns: 1fr 1fr;
  }
}
.service-card {
  background: var(--color-surface);
  border: 1px solid oklch(from var(--color-text) l c h / 0.1);
  border-radius: var(--radius-lg);
  padding: clamp(var(--space-6), 3vw, var(--space-10));
}
.service-card-media {
  padding: 0;
  overflow: hidden;
}
.service-card-media > *:not(.service-card-img) {
  margin-inline: clamp(var(--space-6), 3vw, var(--space-10));
}
.service-card-img {
  margin-bottom: var(--space-6);
  aspect-ratio: 16 / 9;
  overflow: hidden;
}
.service-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.service-card-media .reg-tag {
  margin-left: 0;
}
.service-card-media h3,
.service-card-media p,
.service-card-media ul {
  margin-left: 0;
  padding-bottom: 0;
}
.service-card-media ul {
  margin-bottom: clamp(var(--space-6), 3vw, var(--space-10));
}
.service-card .reg-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--color-steel);
  border: 1px solid oklch(from var(--color-steel) l c h / 0.35);
  border-radius: var(--radius-full);
  padding: var(--space-1) var(--space-3);
  margin-bottom: var(--space-5);
}
.service-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-4);
}
.service-card p {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  margin-bottom: var(--space-6);
}
.service-card ul {
  display: grid;
  gap: var(--space-3);
}
.service-card ul li {
  display: flex;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text);
  align-items: baseline;
}
.service-card ul li::before {
  content: '—';
  color: var(--color-primary);
  flex: none;
}

/* ---------- Process ---------- */

.process {
  background: var(--color-surface-offset);
}
.process-grid {
  display: grid;
  gap: var(--space-8);
  counter-reset: step;
}
@media (min-width: 820px) {
  .process-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
  }
}
.process-step {
  position: relative;
  padding-top: var(--space-5);
  border-top: 2px solid oklch(from var(--color-text) l c h / 0.18);
}
.process-step::before {
  content: '';
  position: absolute;
  top: -2px;
  left: 0;
  width: 44px;
  height: 2px;
  background: var(--color-primary);
}
.process-step .step-num {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
  display: block;
  margin-bottom: var(--space-3);
}
.process-step h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-3);
}
.process-step p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ---------- Full-bleed divider ---------- */

.bleed {
  position: relative;
  min-height: 60vh;
  display: flex;
  align-items: flex-end;
  color: #fff;
}
.bleed img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.bleed-scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    0deg,
    oklch(from var(--color-dark) l c h / 0.88) 0%,
    oklch(from var(--color-dark) l c h / 0.62) 35%,
    oklch(from var(--color-dark) l c h / 0.12) 75%,
    oklch(from var(--color-dark) l c h / 0.02) 100%
  );
}
.bleed-caption {
  position: relative;
  padding-block: var(--space-16);
}
.bleed-caption .mono-label {
  color: #f5c19b;
  display: block;
  margin-bottom: var(--space-4);
  text-shadow: 0 1px 10px oklch(0.15 0.03 250 / 0.55);
}
.bleed-caption p {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 600;
  max-width: 26ch;
  line-height: 1.25;
  color: #fff;
}

/* ---------- Why ---------- */

.why-grid {
  display: grid;
  gap: var(--space-10);
}
@media (min-width: 920px) {
  .why-grid {
    grid-template-columns: 0.9fr 1.1fr;
    gap: var(--space-16);
  }
}
.why-lede {
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-text);
}
.why-points {
  display: grid;
  gap: var(--space-8);
}
.why-point h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
}
.why-point p {
  color: var(--color-text-muted);
  font-size: var(--text-base);
}
.why-point .mono-label {
  color: var(--color-steel);
  display: block;
  margin-bottom: var(--space-2);
}

/* ---------- About (dark) ---------- */

.about {
  background: var(--color-dark);
  color: var(--color-dark-text);
}
.about-grid {
  display: grid;
  gap: var(--space-10);
}
@media (min-width: 920px) {
  .about-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: var(--space-16);
  }
}
.about .section-head h2 {
  color: #fff;
}
.about .section-head p {
  color: var(--color-dark-muted);
}
.about .section-head .mono-label {
  color: #e8a063;
}
.about-body p {
  color: var(--color-dark-muted);
  margin-bottom: var(--space-5);
}
.about-body p strong {
  color: var(--color-dark-text);
  font-weight: 600;
}
.about-facts {
  margin-top: var(--space-8);
  display: grid;
  gap: 1px;
  background: oklch(from #fff l c h / 0.12);
  border: 1px solid oklch(from #fff l c h / 0.12);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.about-facts div {
  background: var(--color-dark-2);
  padding: var(--space-4) var(--space-5);
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
  align-items: baseline;
}
.about-facts dt {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #e8a063;
}
.about-facts dd {
  font-size: var(--text-sm);
  color: var(--color-dark-muted);
  text-align: right;
}

/* ---------- FAQ ---------- */

.faq {
  max-width: 760px;
}
.faq details {
  border-bottom: 1px solid var(--color-divider);
}
.faq summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-5) 0;
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  min-height: 44px;
}
.faq summary::-webkit-details-marker {
  display: none;
}
.faq summary::after {
  content: '+';
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  color: var(--color-primary);
  flex: none;
}
.faq details[open] summary::after {
  content: '−';
}
.faq details p {
  padding: 0 0 var(--space-5) 0;
  color: var(--color-text-muted);
}

/* ---------- Contact ---------- */

.contact {
  background: var(--color-dark);
  color: var(--color-dark-text);
}
.contact-grid {
  display: grid;
  gap: var(--space-10);
}
@media (min-width: 920px) {
  .contact-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
  }
}
.contact h2 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-5);
}
.contact .mono-label {
  color: #e8a063;
  display: block;
  margin-bottom: var(--space-4);
}
.contact-lede {
  color: var(--color-dark-muted);
  font-size: var(--text-lg);
  line-height: 1.5;
  margin-bottom: var(--space-8);
}
.contact-list {
  display: grid;
  gap: var(--space-4);
}
.contact-list li {
  display: flex;
  gap: var(--space-3);
  align-items: baseline;
  font-size: var(--text-base);
  color: var(--color-dark-muted);
}
.contact-list li::before {
  content: '—';
  color: #e8a063;
  flex: none;
}
.contact-list a {
  color: #fff;
  font-weight: 600;
  text-decoration-color: #e8a063;
  text-underline-offset: 4px;
}
.contact-list a:hover {
  color: #e8a063;
}
.contact-panel {
  background: var(--color-dark-2);
  border: 1px solid oklch(from #fff l c h / 0.12);
  border-radius: var(--radius-lg);
  padding: clamp(var(--space-6), 3vw, var(--space-10));
}
.contact-panel h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-4);
}
.contact-panel p {
  color: var(--color-dark-muted);
  font-size: var(--text-sm);
  margin-bottom: var(--space-6);
}
.spec-sheet {
  display: grid;
  gap: 1px;
  background: oklch(from #fff l c h / 0.12);
  border: 1px solid oklch(from #fff l c h / 0.12);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.spec-sheet div {
  background: var(--color-dark);
  padding: var(--space-3) var(--space-4);
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
  align-items: baseline;
}
.spec-sheet dt {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #e8a063;
}
.spec-sheet dd {
  font-size: var(--text-sm);
  color: var(--color-dark-muted);
}

/* ---------- Footer ---------- */

.site-footer {
  background: var(--color-dark);
  color: var(--color-dark-muted);
  border-top: 1px solid oklch(from #fff l c h / 0.1);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-6);
  padding-block: var(--space-8);
}
.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-6);
}
.footer-nav a {
  font-size: var(--text-sm);
  color: var(--color-dark-muted);
  text-decoration: none;
}
.footer-nav a:hover {
  color: #fff;
}
.footer-note {
  padding-block: var(--space-5);
  border-top: 1px solid oklch(from #fff l c h / 0.08);
  font-size: var(--text-xs);
  color: var(--color-dark-muted);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-6);
  justify-content: space-between;
}

/* ---------- Reveal animation ---------- */

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition:
    opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
  }
}