.checkout-form { background: white; padding: 2rem; border-radius: 8px; max-width: 500px; }
.form-group { margin-bottom: 1rem; }
.form-group label { display: block; margin-bottom: 0.5rem; font-weight: bold; }
.form-group input { width: 100%; padding: 0.5rem; border: 1px solid #ddd; border-radius: 4px; }