:root{--brand-primary:#333;--brand-accent:#666;--brand-surface:#fff;--brand-font-heading:system-ui,sans-serif;--brand-radius:8px}*{box-sizing:border-box}body,html{margin:0;padding:0}body{background:var(--brand-surface);color:#222;font-family:system-ui,-apple-system,sans-serif;line-height:1.6}h1,h2,h3{font-family:var(--brand-font-heading)}