:root{--color-bg:#f8f9fa;--color-surface:#fff;--color-border:#e0e0e0;--color-text:#1a1a1a;--color-text-muted:#666;--color-primary:#1a1a1a;--color-primary-hover:#333;--color-bg-hover:#eee;--color-danger:#dc2626;--color-danger-hover:#b91c1c}*,:after,:before{box-sizing:border-box}body{background:var(--color-bg);color:var(--color-text);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:16px;line-height:1.5;margin:0}a{color:var(--color-primary)}a:hover{text-decoration:underline}.btn{align-items:center;border:none;border-radius:6px;cursor:pointer;display:inline-flex;font-size:.9rem;font-weight:500;justify-content:center;padding:.5rem 1rem;text-decoration:none;transition:background .15s,color .15s}.btn:disabled{cursor:not-allowed;opacity:.6}.btn-primary{background:var(--color-primary);color:#fff}.btn-primary:hover:not(:disabled){background:var(--color-primary-hover)}.btn-secondary{background:var(--color-border);color:var(--color-text)}.btn-secondary:hover{background:#d0d0d0}.btn-ghost{background:transparent;color:var(--color-text-muted)}.btn-ghost:hover{background:var(--color-bg-hover);color:var(--color-text)}.btn-danger{background:var(--color-danger);color:#fff}.btn-danger:hover{background:var(--color-danger-hover)}