body {
    background-color: #f8f9fa;
}

.container {
    max-width: 500px;
    margin: auto;
    background: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

#error_message {
    height: 20px;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}