/* Fossall — readable long-form, light theme */

:root {
  --bg: #f7f4ef;
  --fg: #1a1a1a;
  --muted: #5c5c5c;
  --accent: #0b5f4a;
  --accent-hover: #094d3c;
  --card: #fffdf9;
  --border: #ddd5c8;
  --widget: #eef6f3;
  --max: 42rem;
  --font: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 18px;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  color: var(--fg);
  background: var(--bg);
  background-image:
    radial-gradient(ellipse 80% 50% at 100% -20%, rgba(11, 95, 74, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 0% 100%, rgba(11, 95, 74, 0.05), transparent);
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.15em;
}

a:hover {
  color: var(--accent-hover);
}

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 52rem;
  margin: 0 auto;
  padding: 1.25rem 1.25rem 0.5rem;
  font-family: var(--sans);
}

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

.logo:hover {
  color: var(--accent);
}

nav {
  display: flex;
  gap: 1.25rem;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
}

nav a:hover {
  color: var(--accent);
}

main {
  max-width: 52rem;
  margin: 0 auto;
  padding: 1rem 1.25rem 3rem;
}

.hero {
  max-width: var(--max);
  padding: 2rem 0 1rem;
}

.hero h1,
.essay h1 {
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
}

.lede {
  font-size: 1.15rem;
  color: var(--muted);
  max-width: var(--max);
}

.btn {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.65rem 1.1rem;
  font-family: var(--sans);
  font-size: 0.95rem;
  font-weight: 600;
  color: #fff;
  background: var(--accent);
  border-radius: 0.4rem;
  text-decoration: none;
}

.btn:hover {
  background: var(--accent-hover);
  color: #fff;
}

.btn.secondary {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--border);
}

.btn.secondary:hover {
  border-color: var(--accent);
  color: var(--accent-hover);
}

.cards {
  display: grid;
  gap: 1rem;
  margin-top: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
}

.cards article {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1.25rem;
}

.cards h2 {
  font-family: var(--sans);
  font-size: 1rem;
  margin: 0 0 0.5rem;
}

.cards p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--muted);
}

.essay {
  max-width: var(--max);
}

.essay-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.eyebrow {
  font-family: var(--sans);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  margin: 0 0 0.75rem;
}

.essay section {
  margin-bottom: 2.25rem;
}

.essay h2 {
  font-size: 1.35rem;
  margin: 0 0 0.75rem;
}

.essay p,
.essay li {
  color: #2a2a2a;
}

.essay ul,
.essay ol {
  padding-left: 1.25rem;
}

.essay li {
  margin-bottom: 0.4rem;
}

.essay h3 {
  font-family: var(--sans);
  font-size: 1.05rem;
  font-weight: 650;
  margin: 1.5rem 0 0.65rem;
}

.essay .callout {
  margin: 1.25rem 0;
  padding: 0.9rem 1.1rem;
  background: var(--widget);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 0.35rem;
  font-size: 0.98rem;
  color: #2a2a2a;
}

.table-wrap {
  overflow-x: auto;
  margin: 1rem 0 1.35rem;
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.88rem;
  line-height: 1.4;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 0.4rem;
}

.data-table th,
.data-table td {
  text-align: left;
  padding: 0.55rem 0.7rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

.data-table th {
  font-weight: 650;
  color: var(--muted);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: rgba(11, 95, 74, 0.06);
}

.data-table tbody tr:last-child th,
.data-table tbody tr:last-child td {
  border-bottom: none;
}

.data-table .total-row td {
  background: rgba(11, 95, 74, 0.07);
  border-top: 1px solid var(--border);
}

.widget {
  background: var(--widget);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1.25rem;
  margin: 1.5rem 0;
  font-family: var(--sans);
}

.widget h3 {
  margin: 0 0 0.5rem;
  font-size: 1rem;
}

.widget-note {
  font-size: 0.85rem;
  color: var(--muted);
  margin: 0 0 1rem;
}

.widget label {
  display: block;
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
}

.widget input[type="range"] {
  width: 100%;
  max-width: 24rem;
  accent-color: var(--accent);
}

.widget-out {
  margin: 1rem 0 0;
  padding: 0.75rem 1rem;
  background: var(--card);
  border-radius: 0.35rem;
  border: 1px solid var(--border);
  font-variant-numeric: tabular-nums;
  font-size: 0.95rem;
}

/* ── Interactive 3D RV model ─────────────────────────────────────────── */

.rv-model-figure {
  margin: 1.75rem 0 2rem;
  padding: 0;
  max-width: none;
  width: min(100%, 52rem);
  margin-left: 50%;
  transform: translateX(-50%);
  position: relative;
  left: 0;
}

.essay .rv-model-figure {
  /* Break out of narrow essay column for the canvas */
  width: min(100vw - 2rem, 56rem);
  max-width: none;
}

.rv-model-caption {
  font-family: var(--sans);
  margin-bottom: 0.75rem;
}

.rv-model-caption h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 650;
  color: var(--fg);
}

.rv-model-caption p {
  margin: 0;
  font-size: 0.85rem;
  color: var(--muted);
  max-width: 40rem;
}

.rv-model {
  position: relative;
  background: linear-gradient(165deg, #e8e4db 0%, #f0ebe3 45%, #dfe8e3 100%);
  border: 1px solid var(--border);
  border-radius: 0.65rem;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  min-height: 22rem;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.5) inset;
}

.rv-model canvas {
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
  cursor: grab;
}

.rv-model canvas:active {
  cursor: grabbing;
}

.rv-model-toolbar {
  position: absolute;
  left: 0.65rem;
  right: 0.65rem;
  bottom: 0.65rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  font-family: var(--sans);
  pointer-events: none;
}

.rv-model-toolbar > * {
  pointer-events: auto;
}

.rv-model-btn {
  appearance: none;
  border: 1px solid var(--border);
  background: rgba(255, 253, 249, 0.92);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  cursor: pointer;
  backdrop-filter: blur(6px);
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}

.rv-model-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.rv-model-btn.is-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.rv-model-status {
  position: absolute;
  top: 0.65rem;
  left: 0.75rem;
  right: 0.75rem;
  margin: 0;
  font-family: var(--sans);
  font-size: 0.72rem;
  color: var(--muted);
  pointer-events: none;
  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.6);
}

@media (max-width: 40rem) {
  .rv-model {
    aspect-ratio: 4 / 5;
    min-height: 18rem;
  }

  .rv-model-btn {
    font-size: 0.7rem;
    padding: 0.35rem 0.55rem;
  }
}

@media (prefers-color-scheme: dark) {
  .rv-model {
    background: linear-gradient(165deg, #1a1d1a 0%, #151816 50%, #1a2420 100%);
    box-shadow: none;
  }

  .rv-model-btn {
    background: rgba(26, 29, 26, 0.9);
    color: var(--fg);
  }

  .rv-model-btn.is-active {
    background: var(--accent);
    color: #0a1210;
  }

  .rv-model-status {
    text-shadow: none;
  }
}

.closing {
  padding-top: 0.5rem;
  border-top: 1px solid var(--border);
}

.site-footer {
  max-width: 52rem;
  margin: 0 auto;
  padding: 1rem 1.25rem 2.5rem;
  font-family: var(--sans);
  font-size: 0.85rem;
  color: var(--muted);
}

.site-footer p {
  margin: 0;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121412;
    --fg: #eeeae3;
    --muted: #a39e94;
    --accent: #5dba9a;
    --accent-hover: #7dceb2;
    --card: #1a1d1a;
    --border: #2e332e;
    --widget: #1a2420;
  }

  .essay p,
  .essay li {
    color: #ddd8cf;
  }

  .essay .callout {
    color: #ddd8cf;
  }

  .data-table th {
    background: rgba(93, 186, 154, 0.1);
  }

  .data-table .total-row td {
    background: rgba(93, 186, 154, 0.12);
  }

  .btn {
    color: #0a1210;
  }

  .btn:hover {
    color: #0a1210;
  }
}