/* Quiz Loader - Main Styles */

:root {
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --primary-light: #818cf8;
    --secondary: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --bg: #f8fafc;
    --bg-dark: #1e293b;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-light: #64748b;
    --border: #e2e8f0;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
    --radius: 8px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

/* Layout */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    padding: 2rem;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

/* Header */
.header {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
}

.header-nav {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.nav-link {
    color: var(--text-light);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    transition: all 0.2s;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary);
    background: rgba(79, 70, 229, 0.1);
}

/* Cards */
.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border);
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

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

.btn-secondary:hover {
    background: #cbd5e1;
}

.btn-success {
    background: var(--secondary);
    color: white;
}

.btn-danger {
    background: var(--danger);
    color: white;
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    font-size: 0.875rem;
}

.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 0.875rem;
    transition: border-color 0.2s;
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-textarea {
    min-height: 100px;
    resize: vertical;
}

/* Tables */
.table-container {
    overflow-x: auto;
}

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

.table th, .table td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.table th {
    background: var(--bg);
    font-weight: 600;
    font-size: 0.8125rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-light);
}

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

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--card-bg);
    padding: 1.25rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.stat-label {
    font-size: 0.8125rem;
    color: var(--text-light);
    margin-bottom: 0.25rem;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text);
}

.stat-value.primary { color: var(--primary); }
.stat-value.success { color: var(--secondary); }
.stat-value.danger { color: var(--danger); }
.stat-value.warning { color: var(--warning); }

/* Auth Pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.auth-card {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 400px;
}

.auth-title {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 0.5rem;
}

.auth-subtitle {
    color: var(--text-light);
    text-align: center;
    margin-bottom: 2rem;
}

.auth-divider {
    display: flex;
    align-items: center;
    margin: 1.5rem 0;
    color: var(--text-light);
    font-size: 0.875rem;
}

.auth-divider::before, .auth-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--border);
}

.auth-divider span {
    padding: 0 1rem;
}

/* Quiz Taking */
.quiz-container {
    max-width: 800px;
    margin: 0 auto;
}

.question-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 2rem;
    margin-bottom: 1.5rem;
}

.question-number {
    font-size: 0.8125rem;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.question-text {
    font-size: 1.125rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.answer-options {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.answer-option {
    display: flex;
    align-items: center;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s;
}

.answer-option:hover {
    border-color: var(--primary-light);
    background: rgba(79, 70, 229, 0.05);
}

.answer-option.selected {
    border-color: var(--primary);
    background: rgba(79, 70, 229, 0.1);
}

.answer-option.correct {
    border-color: var(--secondary);
    background: rgba(16, 185, 129, 0.1);
}

.answer-option.incorrect {
    border-color: var(--danger);
    background: rgba(239, 68, 68, 0.1);
}

.answer-option input {
    margin-right: 1rem;
}

/* Progress Bar */
.progress-bar {
    background: var(--border);
    border-radius: 9999px;
    height: 8px;
    overflow: hidden;
}

.progress-fill {
    background: var(--primary);
    height: 100%;
    border-radius: 9999px;
    transition: width 0.3s;
}

.progress-fill.success { background: var(--secondary); }
.progress-fill.danger { background: var(--danger); }

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
}

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

.modal {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: transform 0.3s;
}

.modal-overlay.active .modal {
    transform: scale(1);
}

.modal-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-title {
    font-size: 1.125rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-light);
    line-height: 1;
}

.modal-body {
    padding: 1.5rem;
}

.modal-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

/* Alerts */
.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--secondary);
    color: #065f46;
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: #991b1b;
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid var(--warning);
    color: #92400e;
}

/* Badge */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.625rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
}

.badge-primary { background: rgba(79, 70, 229, 0.1); color: var(--primary); }
.badge-success { background: rgba(16, 185, 129, 0.1); color: var(--secondary); }
.badge-danger { background: rgba(239, 68, 68, 0.1); color: var(--danger); }
.badge-warning { background: rgba(245, 158, 11, 0.1); color: var(--warning); }

/* Tabs */
.tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    margin-bottom: 1.5rem;
}

.tab {
    padding: 0.75rem 1.5rem;
    border: none;
    background: none;
    cursor: pointer;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-light);
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

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

.tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

/* File Upload */
.file-upload {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
}

.file-upload:hover {
    border-color: var(--primary);
    background: rgba(79, 70, 229, 0.05);
}

.file-upload-icon {
    font-size: 3rem;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.file-upload-text {
    color: var(--text-light);
}

.file-upload-text strong {
    color: var(--primary);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--text-light);
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

/* Loading Spinner */
.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toast {
    background: var(--card-bg);
    padding: 1rem 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    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(--secondary); }
.toast-error { border-left: 4px solid var(--danger); }

/* Responsive */
@media (max-width: 768px) {
    .header {
        flex-direction: column;
        gap: 1rem;
    }

    .header-nav {
        flex-wrap: wrap;
        justify-content: center;
    }

    .main-content {
        padding: 1rem;
    }

    .stats-grid {
        grid-template-columns: 1fr 1fr;
    }

    .modal {
        margin: 1rem;
    }
}

/* Utility Classes */
.hidden { display: none !important; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-4 { gap: 1rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-4 { margin-top: 1rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }
.text-center { text-align: center; }
.text-sm { font-size: 0.875rem; }
.text-light { color: var(--text-light); }
.font-bold { font-weight: 700; }