.form-input {
    padding: 12px;
    margin: 10px 0;
    border: 2px solid #bdc3c7;
    border-radius: 4px;
    width: 250px;
    transition: border-color 0.3s ease;
}

.form-input:focus {
    outline: none;
    border-color: #3498db;
}

.form-input.error {
    border-color: #e74c3c;
}

.form-input.success {
    border-color: #2ecc71;
}