.signup-container {
    max-width: 800px;
    margin: 50px auto;
    padding: 30px;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

h1 {
    font-size: 2rem;
    color: #333;
}

h2, legend {
    font-size: 1.25rem;
    color: #555;
    border-bottom: 2px solid #007bff;
    padding-bottom: 5px;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-control {
    border-radius: 5px;
    transition: border-color 0.3s ease;
}

.form-control:focus {
    border-color: #007bff;
    box-shadow: 0 0 5px rgba(0, 123, 255, 0.3);
}

.invalid-feedback {
    display: none;
    color: #dc3545;
    font-size: 0.9rem;
}

.form-group.has-danger .form-control {
    border-color: #dc3545;
}

.form-group.has-danger .invalid-feedback {
    display: block;
}

.btn {
    padding: 10px 20px;
    border-radius: 5px;
    font-weight: bold;
}

.btn-primary {
    background-color: #007bff;
    border-color: #007bff;
}

.btn-primary:hover {
    background-color: #0056b3;
    border-color: #0056b3;
}

.btn-outline-secondary {
    color: #6c757d;
    border-color: #6c757d;
}

.btn-outline-secondary:hover {
    background-color: #6c757d;
    color: #fff;
}

.loader {
    position: fixed;
    top: 50%;
    left: 50%;
    width: 60px;
    height: 60px;
    margin: -30px 0 0 -30px;
    border: 8px solid #f3f3f3;
    border-top: 8px solid #007bff;
    border-radius: 50%;
    animation: spin 1.5s linear infinite;
    display: none;
    z-index: 1000;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}