:root{--bg:#fafafa;--fg:#1f1f1f;--muted:#6b6b6b;--border:#e3e3e3;--accent:#2962ff;color:var(--fg);background:var(--bg);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}*{box-sizing:border-box}body{margin:0}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}button{font:inherit;border:1px solid var(--border);cursor:pointer;background:#fff;border-radius:4px;padding:.5rem 1rem}button.primary{background:var(--accent);color:#fff;border-color:var(--accent)}input,textarea{font:inherit;border:1px solid var(--border);border-radius:4px;width:100%;padding:.5rem}.app{grid-template-columns:220px 1fr;min-height:100vh;display:grid}.sidebar{border-right:1px solid var(--border);background:#fff;padding:1.5rem 1rem}.sidebar h1{margin:0 0 1rem;font-size:1rem}.sidebar nav{flex-direction:column;gap:.25rem;display:flex}.sidebar nav a{color:var(--fg);border-radius:4px;padding:.5rem .75rem}.sidebar nav a.active{background:var(--bg);color:var(--accent)}.main{max-width:960px;padding:2rem}.main h2{margin-top:0}.card{border:1px solid var(--border);background:#fff;border-radius:6px;margin-bottom:1rem;padding:1.25rem}.muted{color:var(--muted)}