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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --success-color: #16a34a;
    --danger-color: #dc2626;
    --warning-color: #f59e0b;
    --light-gray: #f3f4f6;
    --dark-gray: #374151;
    --border-color: #e5e7eb;
    --text-color: #1f2937;
    --bg-primary: white;
    --bg-secondary: #f9fafb;
}

body[data-theme="dark"] {
    --primary-color: #3b82f6;
    --secondary-color: #1e3a8a;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #fbbf24;
    --light-gray: #1f2937;
    --dark-gray: #d1d5db;
    --border-color: #374151;
    --text-color: #f3f4f6;
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
}

/* Color Scheme Variables */
:root.scheme-green {
    --primary-color: #059669;
    --secondary-color: #047857;
}

:root.scheme-purple {
    --primary-color: #7c3aed;
    --secondary-color: #6d28d9;
}

:root.scheme-orange {
    --primary-color: #f97316;
    --secondary-color: #ea580c;
}

:root.scheme-red {
    --primary-color: #dc2626;
    --secondary-color: #b91c1c;
}

:root.scheme-pink {
    --primary-color: #ec4899;
    --secondary-color: #db2777;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: var(--text-color);
    transition: background-color 0.3s ease, color 0.3s ease;
}

body[data-theme="dark"] {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: var(--bg-primary);
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.header {
    background: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
    color: white;
    padding: 40px 30px;
    text-align: center;
}

.header h1 {
    font-size: 28px;
    margin-bottom: 10px;
    font-weight: 700;
}

.header p {
    font-size: 14px;
    opacity: 0.9;
}

/* Navigation Bar */
.navbar {
    background: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
    padding: 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    position: sticky;
    top: 0;
    z-index: 999;
}

.navbar-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 30px;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    color: white;
    font-size: 18px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.navbar-brand:hover {
    transform: scale(1.05);
}

.brand-icon {
    font-size: 24px;
}

.brand-text {
    letter-spacing: 0.5px;
}

.navbar-menu {
    position: relative;
}

.nav-item {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 10px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s ease;
}

.nav-item:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
}

.dropdown-arrow {
    font-size: 10px;
    transition: transform 0.2s ease;
}

.nav-item.active .dropdown-arrow {
    transform: rotate(180deg);
}

.profile-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--bg-primary);
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    min-width: 200px;
    z-index: 1000;
    overflow: hidden;
    transition: background-color 0.3s ease;
}

.profile-dropdown.hidden {
    display: none;
}

.dropdown-header {
    padding: 12px 16px;
    font-weight: 600;
    color: var(--text-color);
    font-size: 14px;
    background: var(--light-gray);
}

.dropdown-item {
    display: block;
    width: 100%;
    padding: 12px 16px;
    background: none;
    border: none;
    text-align: left;
    cursor: pointer;
    font-size: 14px;
    color: var(--text-color);
    transition: background 0.2s ease;
}

.dropdown-item:hover {
    background: var(--light-gray);
}

.dropdown-item.logout {
    color: var(--danger-color);
    font-weight: 500;
}

.dropdown-item.logout:hover {
    background: #fef2f2;
}

/* Dark Mode Toggle in Navbar */
.dropdown-dark-mode {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 16px;
    width: 100%;
    cursor: pointer;
    background: none;
    border: none;
    font-size: 14px;
    color: var(--text-color);
    transition: background 0.2s ease;
    user-select: none;
}

.dropdown-dark-mode:hover {
    background: var(--light-gray);
}

.dropdown-dark-mode input[type="checkbox"] {
    cursor: pointer;
    width: 16px;
    height: 16px;
}

/* Name Screen */
.name-screen {
    padding: 60px 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 60vh;
}

.name-screen.hidden {
    display: none;
}

.name-content {
    max-width: 500px;
    text-align: center;
}

.name-content h2 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-color);
}

.name-content p {
    font-size: 16px;
    color: var(--dark-gray);
    margin-bottom: 30px;
}

.name-input {
    width: 100%;
    padding: 15px;
    font-size: 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 20px;
    transition: border-color 0.2s ease;
    background: var(--bg-primary);
    color: var(--text-color);
}

.name-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Leaderboard Screen */
.leaderboard-screen {
    padding: 40px 30px;
}

.leaderboard-screen.hidden {
    display: none;
}

.leaderboard-content {
    max-width: 600px;
    margin: 0 auto;
}

.leaderboard-content h2 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 30px;
    color: var(--text-color);
    text-align: center;
}

.leaderboard-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.leaderboard-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px;
    background: var(--light-gray);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
}

.leaderboard-rank {
    min-width: 40px;
    font-size: 18px;
    font-weight: 700;
    color: var(--primary-color);
}

.leaderboard-rank.gold {
    color: #d97706;
}

.leaderboard-rank.silver {
    color: #9ca3af;
}

.leaderboard-rank.bronze {
    color: #b45309;
}

.leaderboard-info {
    flex: 1;
}

.leaderboard-name {
    font-weight: 600;
    color: var(--text-color);
    font-size: 15px;
}

.leaderboard-details {
    font-size: 12px;
    color: var(--dark-gray);
    margin-top: 4px;
}

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

.leaderboard-score-big {
    font-size: 18px;
    font-weight: 700;
    color: var(--success-color);
}

.leaderboard-score-small {
    font-size: 12px;
    color: var(--dark-gray);
}

.leaderboard-empty {
    text-align: center;
    padding: 40px 20px;
    color: var(--dark-gray);
}

/* Question Review Screen */
.review-screen {
    padding: 40px 30px;
}

.review-screen.hidden {
    display: none;
}

.review-content {
    max-width: 800px;
    margin: 0 auto;
}

.review-content h2 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-color);
    text-align: center;
}

.review-info {
    text-align: center;
    color: var(--dark-gray);
    margin-bottom: 20px;
    font-size: 14px;
}

.review-stats {
    background: var(--light-gray);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid var(--warning-color);
    text-align: center;
}

.review-stats-number {
    font-size: 32px;
    font-weight: 700;
    color: var(--warning-color);
}

.review-stats-label {
    font-size: 14px;
    color: var(--dark-gray);
    margin-top: 5px;
}

.flagged-questions-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.flagged-question-item {
    background: var(--light-gray);
    padding: 20px;
    border-radius: 8px;
    border-left: 4px solid var(--warning-color);
}

.flagged-question-text {
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 12px;
    font-size: 15px;
}

.flagged-question-details {
    font-size: 13px;
    color: var(--dark-gray);
    margin-bottom: 8px;
    line-height: 1.5;
}

.feedback-type-badge {
    display: inline-block;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    margin-right: 8px;
    margin-top: 8px;
}

.feedback-type-badge.wrong {
    background: #fee2e2;
    color: var(--danger-color);
}

.feedback-type-badge.irrelevant {
    background: #fef3c7;
    color: #a16207;
}

.flagged-questions-empty {
    text-align: center;
    padding: 40px 20px;
    color: var(--dark-gray);
}

/* Settings Screen */
.settings-screen {
    padding: 40px 30px;
}

.settings-screen.hidden {
    display: none;
}

.settings-content {
    max-width: 600px;
    margin: 0 auto;
}

.settings-content h2 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 30px;
    color: var(--text-color);
    text-align: center;
}

.settings-section {
    margin-bottom: 30px;
}

.settings-section h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 15px;
}

.settings-item {
    background: var(--bg-secondary);
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 12px;
}

.color-scheme-selector {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(90px, 1fr));
    gap: 12px;
}

.color-option {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 12px;
    border-radius: 8px;
    border: 2px solid var(--border-color);
    background: var(--bg-secondary);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-color);
}

.color-option:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.color-option.active {
    border-color: var(--primary-color);
    background: var(--light-gray);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.color-sample {
    width: 100%;
    height: 50px;
    border-radius: 6px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

/* Student Stats */
.student-stats {
    background: var(--light-gray);
    padding: 20px;
    border-radius: 8px;
    margin: 20px 0;
    border-left: 4px solid var(--primary-color);
}

.student-stats h4 {
    color: var(--text-color);
    margin-bottom: 12px;
    font-size: 14px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
}

.stat-box {
    background: white;
    padding: 12px;
    border-radius: 6px;
    text-align: center;
}

.stat-value {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 12px;
    color: var(--dark-gray);
    margin-top: 4px;
}

/* Header */
.setup-screen {
    padding: 40px 30px;
}

.setup-screen.hidden {
    display: none;
}

.setup-content h2 {
    font-size: 24px;
    margin-bottom: 30px;
    color: var(--text-color);
}

.setup-section {
    margin-bottom: 35px;
}

.setup-section h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 15px;
}

/* Module Buttons */
.module-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 12px;
}

.module-btn {
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: white;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s ease;
    color: var(--text-color);
}

.module-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

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

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

/* Section Checkboxes */
.controls {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.btn-small {
    padding: 8px 14px;
    background: var(--light-gray);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    transition: all 0.2s ease;
    color: var(--text-color);
}

.btn-small:hover {
    background: var(--border-color);
}

.section-checkboxes {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 12px;
    padding: 15px;
    background: var(--light-gray);
    border-radius: 8px;
}

.checkbox-item {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    transition: background 0.2s ease;
}

.checkbox-item:hover {
    background: white;
}

.checkbox-item input[type="checkbox"] {
    cursor: pointer;
    width: 18px;
    height: 18px;
}

.checkbox-item label {
    cursor: pointer;
    flex: 1;
    font-size: 14px;
}

/* Toggle Settings */
.toggle-setting {
    display: flex;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    padding: 12px;
    background: var(--light-gray);
    border-radius: 8px;
    margin-bottom: 10px;
    transition: background 0.2s ease;
}

.toggle-setting:hover {
    background: #e5e7eb;
}

.toggle-setting input[type="checkbox"] {
    cursor: pointer;
    width: 20px;
    height: 20px;
}

.toggle-setting span {
    font-size: 14px;
    font-weight: 500;
}

.setting-note {
    font-size: 13px;
    color: #6b7280;
    margin-left: 32px;
    margin-top: -5px;
}

.section-count {
    font-size: 13px;
    color: #6b7280;
    font-weight: normal;
}

/* Progress Section */
.progress-section {
    padding: 20px 30px;
    background: var(--light-gray);
    border-bottom: 1px solid var(--border-color);
}

.progress-section.hidden {
    display: none;
}

.progress-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    font-size: 14px;
    font-weight: 500;
}

#question-counter {
    color: var(--primary-color);
    font-weight: 600;
}

#section-name {
    background: var(--primary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #d1d5db;
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #10b981, #059669);
    border-radius: 10px;
    transition: width 0.3s ease;
    width: 0%;
}

/* Quiz Container */
.quiz-container {
    padding: 40px 30px;
    min-height: 500px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.quiz-container.hidden {
    display: none;
}

.question-card {
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.question-text {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 30px;
    line-height: 1.6;
}

.options {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 30px;
}

.option {
    padding: 18px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: white;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 15px;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 12px;
}

.option:hover:not(.disabled) {
    border-color: var(--primary-color);
    background: #f0f4ff;
    transform: translateX(4px);
}

.option.selected {
    border-color: var(--primary-color);
    background: var(--primary-color);
    color: white;
}

.option.correct {
    border-color: var(--success-color);
    background: var(--success-color);
    color: white;
}

.option.incorrect {
    border-color: var(--danger-color);
    background: var(--danger-color);
    color: white;
}

.option.disabled {
    cursor: not-allowed;
}

.option-letter {
    min-width: 24px;
    text-align: center;
    font-weight: 700;
}

.feedback-badge {
    margin-left: auto;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 8px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.2);
}

/* Buttons */
.button-group {
    display: flex;
    gap: 12px;
    justify-content: space-between;
    margin-top: 30px;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

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

.btn-secondary {
    background: var(--light-gray);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    flex: 0 0 auto;
}

.btn-secondary:hover:not(:disabled) {
    background: #e5e7eb;
}

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

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

.btn-danger:hover {
    background: #b91c1c;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(220, 38, 38, 0.3);
}

.btn-large {
    padding: 16px 32px;
    font-size: 16px;
    width: 100%;
    margin-top: 20px;
}

.button-group .btn-primary {
    flex: 1;
}

/* Question Feedback Buttons */
.question-feedback-buttons {
    display: flex;
    gap: 10px;
    margin: 20px 0;
    justify-content: center;
    flex-wrap: wrap;
}

.btn-feedback-thumbs {
    padding: 10px 16px;
    font-size: 14px;
    border: 2px solid var(--border-color);
    background: white;
    color: var(--text-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.btn-feedback-thumbs:hover {
    border-color: var(--warning-color);
    background: #fef3c7;
}

.btn-feedback-thumbs.flagged {
    border-color: var(--danger-color);
    background: #fee2e2;
    color: var(--danger-color);
}

/* Flag Success Message */
.flag-success-message {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: 15px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    font-weight: 500;
    font-size: 14px;
    z-index: 10000;
    opacity: 0;
    transform: translateX(400px);
    transition: all 0.3s ease;
}

.flag-success-message.show {
    opacity: 1;
    transform: translateX(0);
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: white;
    padding: 30px;
    border-radius: 12px;
    max-width: 400px;
    width: 90%;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: slideIn 0.3s ease;
}

.modal-content h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--text-color);
}

.modal-content p {
    font-size: 14px;
    color: var(--dark-gray);
    margin-bottom: 25px;
    line-height: 1.5;
}

.modal .button-group {
    margin-top: 0;
    gap: 10px;
}

.modal .btn {
    padding: 10px 20px;
    font-size: 13px;
    flex: 1;
}

/* Results Container */
.results-container {
    padding: 40px 30px;
    text-align: center;
}

.results-container.hidden {
    display: none;
}

.results-content h2 {
    font-size: 32px;
    color: var(--text-color);
    margin-bottom: 30px;
    font-weight: 700;
}

.score-display {
    margin-bottom: 30px;
}

.score-circle {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    background: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    margin: 0 auto;
    box-shadow: 0 10px 30px rgba(37, 99, 235, 0.2);
}

.score-circle span:first-child {
    font-size: 60px;
    font-weight: 700;
}

.score-label {
    font-size: 16px;
    opacity: 0.9;
    margin-top: 5px;
}

.percentage-display {
    font-size: 24px;
    font-weight: 600;
    color: var(--text-color);
    margin: 20px 0;
}

.summary-stats {
    background: var(--light-gray);
    padding: 20px;
    border-radius: 8px;
    margin: 20px 0 30px 0;
    font-size: 16px;
    color: var(--dark-gray);
}

.stat-line {
    padding: 8px 0;
}

.stat-line strong {
    color: var(--primary-color);
}

/* Wrong Answers Section */
.wrong-answers-section {
    text-align: left;
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.wrong-answers-section h3 {
    color: #991b1b;
    margin-bottom: 15px;
    font-size: 16px;
}

.wrong-answers-list {
    max-height: 400px;
    overflow-y: auto;
}

.wrong-answer-item {
    background: white;
    border-left: 4px solid var(--danger-color);
    padding: 15px;
    margin-bottom: 10px;
    border-radius: 4px;
    font-size: 14px;
}

.wrong-answer-item strong {
    display: block;
    margin-bottom: 8px;
    color: var(--text-color);
}

.wrong-answer-item .your-answer {
    color: var(--danger-color);
    font-weight: 500;
    margin-bottom: 4px;
}

.wrong-answer-item .correct-answer {
    color: var(--success-color);
    font-weight: 500;
}

/* Comprehensive Dark Mode Styling */
body[data-theme="dark"] .header {
    background: linear-gradient(135deg, #1e40af 0%, #1e3a8a 100%);
}

body[data-theme="dark"] .btn,
body[data-theme="dark"] .btn-small {
    background: var(--bg-secondary);
    color: var(--text-color);
    border-color: var(--border-color);
    transition: all 0.3s ease;
}

body[data-theme="dark"] .btn-primary {
    background: var(--primary-color);
    color: white;
}

body[data-theme="dark"] .btn-primary:hover:not(:disabled) {
    background: var(--secondary-color);
}

body[data-theme="dark"] .btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-color);
    border: 2px solid var(--border-color);
}

body[data-theme="dark"] .btn-secondary:hover:not(:disabled) {
    background: var(--dark-gray);
    border-color: var(--text-color);
}

body[data-theme="dark"] .btn-danger {
    background: #dc2626;
    color: white;
}

body[data-theme="dark"] .btn-danger:hover {
    background: #b91c1c;
}

body[data-theme="dark"] .option {
    background: var(--bg-secondary);
    color: var(--text-color);
    border: 2px solid var(--border-color);
}

body[data-theme="dark"] .option:hover {
    border-color: var(--primary-color);
    background: var(--dark-gray);
}

body[data-theme="dark"] .option.correct {
    background: #064e3b;
    border-color: #10b981;
    color: #d1fae5;
}

body[data-theme="dark"] .option.incorrect {
    background: #7f1d1d;
    border-color: #ef4444;
    color: #fee2e2;
}

body[data-theme="dark"] .question-card {
    background: var(--bg-primary);
    border-color: var(--border-color);
}

body[data-theme="dark"] .checkbox-item {
    background: var(--bg-secondary);
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 8px;
}

body[data-theme="dark"] .checkbox-item input[type="checkbox"] {
    accent-color: var(--primary-color);
}

body[data-theme="dark"] .toggle-setting input[type="checkbox"] {
    accent-color: var(--primary-color);
}

body[data-theme="dark"] .score-circle {
    background: var(--bg-secondary);
    border-color: var(--border-color);
}

body[data-theme="dark"] .score-circle span {
    color: var(--text-color);
}

body[data-theme="dark"] .feedback-badge {
    color: inherit;
}

body[data-theme="dark"] .name-screen,
body[data-theme="dark"] .setup-screen,
body[data-theme="dark"] .quiz-container,
body[data-theme="dark"] .results-container,
body[data-theme="dark"] .leaderboard-screen,
body[data-theme="dark"] .review-screen,
body[data-theme="dark"] .settings-screen {
    background: var(--bg-primary);
    color: var(--text-color);
}

body[data-theme="dark"] .leaderboard-item {
    background: var(--bg-secondary);
    border-left-color: var(--primary-color);
}

body[data-theme="dark"] .flagged-question-item {
    background: var(--bg-secondary);
    border-left-color: var(--warning-color);
}

body[data-theme="dark"] .btn-feedback-thumbs {
    background: var(--bg-secondary);
    border-color: var(--border-color);
    color: var(--text-color);
}

body[data-theme="dark"] .btn-feedback-thumbs:hover {
    border-color: var(--warning-color);
    background: #451a03;
}

body[data-theme="dark"] .btn-feedback-thumbs.flagged {
    border-color: var(--danger-color);
    background: #7f1d1d;
    color: var(--danger-color);
}

body[data-theme="dark"] .settings-item {
    background: var(--dark-gray);
}

body[data-theme="dark"] .color-option {
    background: var(--bg-secondary);
    border-color: var(--border-color);
    color: var(--text-color);
}

body[data-theme="dark"] .color-option.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

body[data-theme="dark"] .modal-content {
    background: var(--bg-primary);
    color: var(--text-color);
}

body[data-theme="dark"] hr {
    border-color: var(--border-color);
}

/* Input / Code Completion Questions */
.input-answer-container {
    display: flex;
    gap: 12px;
    align-items: center;
    margin: 20px 0;
    flex-wrap: wrap;
}

.text-answer-input {
    flex: 1;
    min-width: 200px;
    padding: 12px 16px;
    font-size: 16px;
    font-family: 'Courier New', monospace;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-primary);
    color: var(--text-color);
    transition: border-color 0.2s ease;
}

.text-answer-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.text-answer-input[readonly] {
    cursor: default;
    opacity: 0.85;
}

.text-answer-input.input-correct {
    border-color: var(--success-color);
    background: #f0fdf4;
}

.text-answer-input.input-incorrect {
    border-color: var(--danger-color);
    background: #fef2f2;
}

.input-feedback {
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 14px;
    margin-bottom: 10px;
}

.input-feedback-correct {
    background: #f0fdf4;
    color: var(--success-color);
    border-left: 4px solid var(--success-color);
}

.input-feedback-incorrect {
    background: #fef2f2;
    color: var(--danger-color);
    border-left: 4px solid var(--danger-color);
}

.input-feedback-neutral {
    background: var(--light-gray);
    color: var(--dark-gray);
    border-left: 4px solid var(--primary-color);
}

body[data-theme="dark"] .text-answer-input {
    background: var(--bg-secondary);
    border-color: var(--border-color);
    color: var(--text-color);
}

body[data-theme="dark"] .text-answer-input.input-correct {
    background: #052e16;
    border-color: var(--success-color);
}

body[data-theme="dark"] .text-answer-input.input-incorrect {
    background: #2d0a0a;
    border-color: var(--danger-color);
}

/* Responsive */
@media (max-width: 768px) {
    .navbar-container {
        padding: 12px 20px;
    }

    .brand-text {
        font-size: 16px;
    }

    .nav-item {
        padding: 8px 12px;
        font-size: 13px;
    }

    .profile-dropdown {
        min-width: 180px;
    }

    .header {
        padding: 30px 20px;
    }

    .header h1 {
        font-size: 22px;
    }

    .setup-screen,
    .quiz-container,
    .results-container {
        padding: 25px 20px;
    }

    .question-text {
        font-size: 16px;
    }

    .button-group {
        flex-direction: column;
    }

    .option {
        padding: 15px;
        font-size: 14px;
    }

    .progress-info {
        flex-direction: column;
        gap: 10px;
        align-items: flex-start;
    }

    .score-circle {
        width: 140px;
        height: 140px;
    }

    .score-circle span:first-child {
        font-size: 48px;
    }

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

    .section-checkboxes {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .navbar-container {
        padding: 10px 15px;
    }

    .brand-text {
        display: none;
    }

    .brand-icon {
        font-size: 22px;
    }

    .nav-item {
        padding: 8px 10px;
        font-size: 12px;
    }

    #nav-student-name {
        max-width: 100px;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
    }

    .profile-dropdown {
        min-width: 150px;
        right: -10px;
    }

    .container {
        border-radius: 0;
    }

    .header {
        padding: 20px 15px;
    }

    .header h1 {
        font-size: 20px;
    }

    .progress-section {
        padding: 15px;
    }

    .setup-screen,
    .quiz-container,
    .results-container {
        padding: 20px 15px;
    }

    .question-text {
        font-size: 14px;
        margin-bottom: 20px;
    }

    .option {
        padding: 12px;
        font-size: 13px;
    }

    .module-buttons {
        grid-template-columns: 1fr;
    }
}