body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 20px;
}
.container {
    max-width: 600px;
    margin: auto;
    padding: 20px;
    position: relative;
}
.form-group {
    margin-bottom: 15px;
}
.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}
.form-group input {
    width: 100%;
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-size: 16px;
}

.form-group input[type="radio"] {
    width: auto;
    margin-right: 5px;
}
.form-group .radio-group {
    display: flex;
    gap: 20px;
}
.form-group .radio-group label {
    margin: 0;
}
.form-group button {
    padding: 10px 15px;
    background-color: #007BFF;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
}
.form-group button:disabled {
    background-color: #cccccc;
}
.loader {
    display: none;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #007BFF;
    border-radius: 50%;
    width: 30px;
    height: 30px;
    animation: spin 2s linear infinite;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(255, 255, 255, 0.7);
    z-index: 10;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}
.message {
    display: none;
    margin-top: 20px;
    padding: 10px;
    border-radius: 4px;
    font-size: 16px;
}
.message.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}
.message.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}