:root {
    --primary-color: #2c4482;
    --secondary-color: #f8f9fa;
    --text-color: #212529;
    --light-text: #6c757d;
    --accent-color: #ff7b54;
    --border-radius: 10px;
    --box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #f5f8fb;
    padding: 20px;
}

.auth-card {
    width: 100%;
    max-width: 450px;
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    overflow: hidden;
}

.auth-header {
    text-align: center;
    padding: 30px 20px 20px;
    background-color: var(--primary-color);
    color: white;
}

.auth-header h2 {
    margin: 0 0 5px;
    font-weight: 600;
    font-size: 24px;
}

.auth-header p {
    margin: 0;
    opacity: 0.85;
    font-size: 14px;
}

.auth-tabs {
    display: flex;
    border-bottom: 1px solid #eee;
}

.auth-tab {
    flex: 1;
    text-align: center;
    padding: 15px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
    color: var(--light-text);
    text-decoration: none;
}

.auth-tab:hover {
    color: var(--primary-color);
}

.auth-tab.active {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

.auth-body {
    padding: 25px;
}

.form-floating > .form-control:focus ~ label,
.form-floating > .form-control:not(:placeholder-shown) ~ label {
    color: var(--primary-color);
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.25rem rgba(44, 68, 130, 0.25);
}

.forgot-password {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 14px;
}

.forgot-password:hover {
    text-decoration: underline;
    color: var(--primary-color);
}

.auth-button {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    padding: 12px;
    font-weight: 500;
    transition: all 0.2s ease;
    /* iOS 触摸优化 */
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
    cursor: pointer;
}

.auth-button:hover,
.auth-button:focus {
    background-color: #243a70;
    border-color: #243a70;
}

.auth-button:active {
    transform: scale(0.98);
    background-color: #1f3464;
}

.form-check-input:checked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline-primary {
    color: var(--primary-color);
    border-color: var(--primary-color);
    /* iOS 触摸优化 */
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
    cursor: pointer;
}

.btn-outline-primary:hover,
.btn-outline-primary:focus {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.btn-outline-primary:active {
    transform: scale(0.98);
    background-color: #243a70;
    border-color: #243a70;
}

/* Loading state for buttons */
.auth-button.is-loading {
    position: relative;
    color: transparent !important;
}

.auth-button.is-loading::after {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    top: calc(50% - 10px);
    left: calc(50% - 10px);
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.reset-step {
    transition: all 0.3s ease;
}

/* Responsive adjustments */
@media (max-width: 576px) {
    .auth-card {
        max-width: 100%;
    }
    
    .auth-header h2 {
        font-size: 22px;
    }
}

/* Checkbox validation styles */
.form-check-input.is-invalid {
    border-color: #dc3545;
    box-shadow: 0 0 0 0.2rem rgba(220, 53, 69, 0.25);
}

.form-check .invalid-feedback {
    display: none;
    font-size: 0.875rem;
    color: #dc3545;
    margin-top: 0.25rem;
}

.form-check-input.is-invalid ~ .invalid-feedback {
    display: block;
}