/* Thomas R&D LLC — shared stylesheet. No external fonts or assets. */
:root {
  --bg: #fbfbfa;
  --surface: #ffffff;
  --text: #1c1f23;
  --muted: #5b636e;
  --border: #e4e6e9;
  --accent: #2f5d50;
  --maxw: 46rem;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141618;
    --surface: #1b1e21;
    --text: #e7e9eb;
    --muted: #9aa3ad;
    --border: #2c3136;
    --accent: #7fbfaa;
  }
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 1.0625rem;
  line-height: 1.65;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

a { color: var(--accent); text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }

.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header */
.site-header { border-bottom: 1px solid var(--border); background: var(--surface); }
.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding-top: 1rem;
  padding-bottom: 1rem;
}
.brand {
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  color: var(--text);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 1.9rem;
  height: 1.9rem;
  border-radius: 0.45rem;
  background: var(--accent);
  color: var(--surface);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0;
}
.site-footer a { color: var(--muted); }

@media (max-width: 560px) {
  body { font-size: 1rem; }
  main { padding: 2rem 0 3rem; }
  h1 { font-size: 1.75rem; }
  .hero h1 { font-size: 2rem; }
  .lede { font-size: 1.08rem; }
}