/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-3) var(--spacing-5);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: var(--border-radius-lg);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
    color: white;
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--primary-400), var(--primary-500));
    transform: translateY(-2px);
}

.btn-secondary {
    background: var(--bg-glass);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--primary-500);
}

.btn-success {
    background: linear-gradient(135deg, var(--success-500), var(--success-600));
    color: white;
}

.btn-danger {
    background: linear-gradient(135deg, var(--error-500), var(--error-600));
    color: white;
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}

.btn-ghost:hover:not(:disabled) {
    background: var(--bg-glass);
    color: var(--text-primary);
}

.btn-sm {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: 0.75rem;
}

.btn-lg {
    padding: var(--spacing-4) var(--spacing-8);
    font-size: 1rem;
}

.btn-icon {
    width: 40px;
    height: 40px;
    padding: 0;
}

/* Forms */
.form-group {
    margin-bottom: var(--spacing-5);
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-2);
}

.form-label.required::after {
    content: '*';
    color: var(--error-500);
    margin-left: var(--spacing-1);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--spacing-3) var(--spacing-4);
    font-size: 0.875rem;
    font-family: inherit;
    background: var(--bg-glass);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-input::placeholder {
    color: var(--text-muted);
}

.form-select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%239ca3af'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
    padding-right: 40px;
}

.form-select option {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.form-textarea {
    min-height: 120px;
    resize: vertical;
}

.form-checkbox {
    width: 20px;
    height: 20px;
    accent-color: var(--primary-500);
    cursor: pointer;
}

.form-radio {
    width: 18px;
    height: 18px;
    accent-color: var(--primary-500);
    cursor: pointer;
}

.form-error {
    font-size: 0.75rem;
    color: var(--error-500);
    margin-top: var(--spacing-1);
}

.form-radio-group {
    display: flex;
    gap: var(--spacing-6);
}

.form-radio-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    cursor: pointer;
}

/* Table */
.table-container {
    overflow-x: auto;
    border-radius: var(--border-radius-xl);
    border: 1px solid var(--border-color);
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th,
.table td {
    padding: var(--spacing-4);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    background: var(--bg-glass);
}

.table td {
    font-size: 0.875rem;
}

.table tbody tr {
    transition: background var(--transition-fast);
}

.table tbody tr:hover {
    background: var(--bg-glass);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-1);
    padding: var(--spacing-1) var(--spacing-3);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--border-radius-full);
}

.badge-primary {
    background: rgba(99, 102, 241, 0.2);
    color: var(--primary-400);
}

.badge-success {
    background: rgba(16, 185, 129, 0.2);
    color: var(--success-500);
}

.badge-error {
    background: rgba(239, 68, 68, 0.2);
    color: var(--error-500);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.2);
    color: var(--warning-500);
}

.badge-gray {
    background: rgba(107, 114, 128, 0.2);
    color: var(--gray-400);
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.modal-overlay.open {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-2xl);
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow: hidden;
    transform: scale(0.95) translateY(20px);
    transition: transform var(--transition-normal);
}

.modal-overlay.open .modal {
    transform: scale(1) translateY(0);
}

.modal-lg {
    max-width: 900px;
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-6);
    border-bottom: 1px solid var(--border-color);
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 600;
}

.modal-close {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius-lg);
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
}

.modal-close:hover {
    background: var(--bg-glass);
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-6);
    overflow-y: auto;
    max-height: calc(90vh - 140px);
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-3);
    padding: var(--spacing-6);
    border-top: 1px solid var(--border-color);
}

/* Alerts */
.alert {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-3);
    padding: var(--spacing-4) var(--spacing-5);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-4);
}

.alert-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

.alert-content {
    flex: 1;
}

.alert-title {
    font-weight: 600;
    margin-bottom: var(--spacing-1);
}

.alert-message {
    font-size: 0.875rem;
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.alert-success .alert-icon,
.alert-success .alert-title {
    color: var(--success-500);
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

.alert-error .alert-icon,
.alert-error .alert-title {
    color: var(--error-500);
}

/* Question Card */
.question-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-6);
    margin-bottom: var(--spacing-6);
}

.question-header {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-3);
    margin-bottom: var(--spacing-4);
}

.question-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-2);
}

.question-number {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary-400);
}

.question-text {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: var(--spacing-5);
}

.question-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.question-option {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-3);
    padding: var(--spacing-4);
    background: var(--bg-glass);
    border: 2px solid transparent;
    border-radius: var(--border-radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.question-option:hover {
    background: rgba(99, 102, 241, 0.1);
    border-color: var(--primary-500);
}

.question-option.selected {
    background: rgba(99, 102, 241, 0.15);
    border-color: var(--primary-500);
}

.question-option.correct {
    background: rgba(16, 185, 129, 0.15);
    border-color: var(--success-500);
}

.question-option.incorrect {
    background: rgba(239, 68, 68, 0.15);
    border-color: var(--error-500);
}

.question-option-letter {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    font-weight: 600;
    font-size: 0.875rem;
    flex-shrink: 0;
}

.question-option.selected .question-option-letter {
    background: var(--primary-500);
    color: white;
}

.question-option.correct .question-option-letter {
    background: var(--success-500);
    color: white;
}

.question-option.incorrect .question-option-letter {
    background: var(--error-500);
    color: white;
}

.question-option-text {
    flex: 1;
    padding-top: var(--spacing-1);
}

.vf-options {
    display: flex;
    gap: var(--spacing-4);
}

.vf-option {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-4) var(--spacing-6);
    background: var(--bg-glass);
    border: 2px solid transparent;
    border-radius: var(--border-radius-lg);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-fast);
}

.vf-option:hover {
    background: rgba(99, 102, 241, 0.1);
}

.vf-option.selected {
    background: rgba(99, 102, 241, 0.15);
    border-color: var(--primary-500);
}

.vf-option.correct {
    background: rgba(16, 185, 129, 0.15);
    border-color: var(--success-500);
}

.vf-option.incorrect {
    background: rgba(239, 68, 68, 0.15);
    border-color: var(--error-500);
}

.question-explanation {
    margin-top: var(--spacing-5);
    padding: var(--spacing-4);
    background: rgba(99, 102, 241, 0.1);
    border-left: 4px solid var(--primary-500);
    border-radius: 0 var(--border-radius-lg) var(--border-radius-lg) 0;
}

.question-explanation-title {
    font-weight: 600;
    color: var(--primary-400);
    margin-bottom: var(--spacing-2);
}

/* Progress */
.progress-bar {
    height: 8px;
    background: var(--bg-glass);
    border-radius: var(--border-radius-full);
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-500), var(--primary-400));
    border-radius: var(--border-radius-full);
    transition: width 0.35s ease;
}

.progress-bar-fill.success {
    background: linear-gradient(90deg, var(--success-500), var(--success-600));
}

.progress-bar-fill.error {
    background: linear-gradient(90deg, var(--error-500), var(--error-600));
}

/* Page Header */
.page-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-8);
}

.page-title {
    font-size: 1.875rem;
    font-weight: 700;
}

.page-subtitle {
    font-size: 1rem;
    color: var(--text-muted);
    margin-top: var(--spacing-1);
}

.page-actions {
    display: flex;
    gap: var(--spacing-3);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-16) var(--spacing-8);
}

.empty-state-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-6);
    background: var(--bg-glass);
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
}

.empty-state-icon svg {
    width: 40px;
    height: 40px;
    color: var(--text-muted);
}

.empty-state-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-2);
}

.empty-state-description {
    color: var(--text-muted);
    margin-bottom: var(--spacing-6);
}

/* Spinner */
.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-500);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.loading-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 15, 35, 0.9);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-4);
    z-index: 9999;
}

/* Toast */
.toast-container {
    position: fixed;
    top: var(--spacing-6);
    right: var(--spacing-6);
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.toast {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    padding: var(--spacing-4) var(--spacing-5);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-xl);
    min-width: 300px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }

    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast.success {
    border-left: 4px solid var(--success-500);
}

.toast.error {
    border-left: 4px solid var(--error-500);
}

.toast-icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.toast.success .toast-icon {
    color: var(--success-500);
}

.toast.error .toast-icon {
    color: var(--error-500);
}

.toast-content {
    flex: 1;
}

.toast-message {
    font-size: 0.875rem;
}

.toast-close {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: var(--spacing-1);
}

/* Tabs */
.tabs {
    display: flex;
    gap: var(--spacing-1);
    background: var(--bg-glass);
    padding: var(--spacing-1);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-6);
}

.tab {
    flex: 1;
    padding: var(--spacing-3) var(--spacing-5);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
    background: transparent;
    border: none;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.tab.active {
    background: var(--primary-600);
    color: white;
}

/* Filter Bar */
.filter-bar {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-6);
    padding: var(--spacing-4);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-xl);
}

.filter-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2);
    min-width: 150px;
}

.filter-label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
}

/* Charts */
.chart-container {
    position: relative;
    width: 100%;
    height: 300px;
}

/* Utilities */
.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

.text-primary {
    color: var(--primary-400);
}

.text-success {
    color: var(--success-500);
}

.text-error {
    color: var(--error-500);
}

.text-muted {
    color: var(--text-muted);
}

.text-sm {
    font-size: 0.875rem;
}

.text-lg {
    font-size: 1.125rem;
}

.font-bold {
    font-weight: 700;
}

.mt-2 {
    margin-top: var(--spacing-2);
}

.mt-4 {
    margin-top: var(--spacing-4);
}

.mt-6 {
    margin-top: var(--spacing-6);
}

.mb-2 {
    margin-bottom: var(--spacing-2);
}

.mb-4 {
    margin-bottom: var(--spacing-4);
}

.mb-6 {
    margin-bottom: var(--spacing-6);
}

.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.items-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

.gap-2 {
    gap: var(--spacing-2);
}

.gap-4 {
    gap: var(--spacing-4);
}

.gap-6 {
    gap: var(--spacing-6);
}

.grid {
    display: grid;
}

.grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
}

@media (max-width: 768px) {

    .grid-cols-2,
    .grid-cols-3 {
        grid-template-columns: 1fr;
    }
}

.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

/* Auth Pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-4);
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-2xl);
    padding: var(--spacing-8);
    backdrop-filter: blur(10px);
}

.auth-logo {
    text-align: center;
    margin-bottom: var(--spacing-8);
}

.auth-logo-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-500), var(--primary-700));
    border-radius: var(--border-radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-4);
    font-size: 1.5rem;
    box-shadow: var(--shadow-glow);
}

.auth-logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-400), var(--primary-600));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.auth-title {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-2);
}

.auth-subtitle {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: var(--spacing-6);
}

.auth-footer {
    text-align: center;
    margin-top: var(--spacing-6);
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* Options Container for Question Form */
.options-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.option-row {
    display: flex;
    gap: var(--spacing-3);
    align-items: center;
}

.option-letter-badge {
    min-width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-600);
    border-radius: var(--border-radius-md);
    font-weight: 600;
}

.option-input {
    flex: 1;
}

.option-actions {
    display: flex;
    gap: var(--spacing-2);
}