.submit-btn {
    width: 100%;
    background: linear-gradient(135deg, #dc3545, #c82333);
    border-color: rgba(220, 53, 69, 0.5);
}

.submit-btn:hover:not(:disabled) {
    background: linear-gradient(135deg, #c82333, #bd2130);
    border-color: rgba(220, 53, 69, 0.8);
}