/* Mobile-first, sem frameworks. */
:root {
  --primary: #0d9488;
  --text: #1a2233;
  --bg: #f3f6f9;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.5;
}
.container { max-width: 960px; margin: 0 auto; padding: 1rem; }
h1 { color: var(--primary); }