:root{--bg: #f8fafc;--card: #ffffff;--text: #0f172a;--muted: #475569;--border: #e2e8f0;--accent: #0d9488}*{box-sizing:border-box}body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,sans-serif;font-size:1rem;line-height:1.6;color:var(--text);background:var(--bg)}header{background:var(--card);border-bottom:1px solid var(--border);padding:1rem 1.25rem}header .inner{max-width:44rem;margin:0 auto;display:flex;align-items:center;justify-content:space-between;gap:1rem}.brand{font-weight:700;font-size:1.125rem;color:var(--accent);text-decoration:none}nav a{color:var(--muted);text-decoration:none;font-size:.9375rem}nav a:hover{color:var(--accent)}main{max-width:44rem;margin:0 auto;padding:2rem 1.25rem 4rem}h1{font-size:1.75rem;margin:0 0 .5rem;line-height:1.25}.effective{color:var(--muted);font-size:.875rem;margin:0 0 2rem}h2{font-size:1.125rem;margin:2rem 0 .75rem}p,ul{margin:0 0 1rem;color:var(--text)}ul{padding-left:1.25rem}.muted{color:var(--muted);font-size:.9375rem}footer{border-top:1px solid var(--border);padding:1.5rem 1.25rem;text-align:center;color:var(--muted);font-size:.875rem;background:var(--card)}