/* ===== Course Page Styles ===== */

/* Course Layout */
.course-layout {
    display: flex;
    min-height: 100vh;
    padding-top: 70px;
}

/* Sidebar */
.sidebar {
    width: 300px;
    background: var(--background-medium);
    border-right: 1px solid var(--border-color);
    position: fixed;
    top: 70px;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 100;
    transition: transform 0.3s ease;
}

.sidebar-header {
    padding: 25px 20px;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 5px;
}

.sidebar-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.lesson-list {
    padding: 15px 0;
}

.lesson-item {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 3px solid transparent;
}

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

.lesson-item.active {
    background: rgba(99, 102, 241, 0.1);
    border-left-color: var(--primary-color);
}

.lesson-item.completed {
    opacity: 0.8;
}

.lesson-number {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--background-dark);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    font-weight: 600;
    margin-right: 15px;
    flex-shrink: 0;
}

.lesson-item.completed .lesson-number {
    background: var(--success-color);
    border-color: var(--success-color);
    color: white;
}

.lesson-item.active .lesson-number {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.lesson-info {
    flex: 1;
    min-width: 0;
}

.lesson-title {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 3px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.lesson-duration {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.lesson-status {
    margin-left: 10px;
    font-size: 1rem;
}

.exam-item {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid var(--border-color);
}

.exam-item .lesson-number {
    background: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 300px;
    padding: 40px 60px;
    max-width: calc(100% - 300px);
}

/* Progress Bar */
.progress-container {
    margin-bottom: 40px;
}

.progress-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.progress-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.progress-percentage {
    font-weight: 600;
    color: var(--primary-color);
}

.progress-bar {
    height: 8px;
    background: var(--background-light);
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 10px;
    transition: width 0.5s ease;
}

/* Lesson Content */
.lesson-content {
    max-width: 800px;
}

.lesson-header {
    margin-bottom: 40px;
}

.lesson-badge {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 15px;
}

.lesson-main-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
    line-height: 1.3;
}

.lesson-intro {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* Content Sections */
.content-section {
    margin-bottom: 50px;
}

.content-section h2 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
}

.content-section h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin: 30px 0 15px;
    color: var(--text-primary);
}

.content-section h4 {
    font-size: 1.15rem;
    font-weight: 600;
    margin: 20px 0 10px;
    color: var(--primary-light);
}

.content-section p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 15px;
}

.content-section ul,
.content-section ol {
    margin: 15px 0;
    padding-left: 25px;
}

.content-section li {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 10px;
}

.content-section strong {
    color: var(--text-primary);
}

/* Info Box */
.info-box {
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid var(--primary-color);
    border-radius: var(--radius-md);
    padding: 20px 25px;
    margin: 25px 0;
}

.info-box.warning {
    background: rgba(245, 158, 11, 0.1);
    border-color: var(--warning-color);
}

.info-box.success {
    background: rgba(34, 197, 94, 0.1);
    border-color: var(--success-color);
}

.info-box-title {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.info-box.warning .info-box-title {
    color: var(--warning-color);
}

.info-box.success .info-box-title {
    color: var(--success-color);
}

.info-box p {
    margin: 0;
}

/* Chart Container */
.chart-container {
    background: var(--background-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    margin: 25px 0;
}

.chart-image {
    width: 100%;
    border-radius: var(--radius-sm);
    margin-bottom: 15px;
}

.chart-caption {
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-muted);
    font-style: italic;
}

/* Tables */
.table-container {
    overflow-x: auto;
    margin: 25px 0;
}

.content-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--background-medium);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.content-table th,
.content-table td {
    padding: 15px 20px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.content-table th {
    background: var(--background-light);
    font-weight: 600;
    color: var(--text-primary);
}

.content-table td {
    color: var(--text-secondary);
}

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

/* Key Terms */
.key-terms {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin: 25px 0;
}

.term-card {
    background: var(--background-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
}

.term-name {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.term-definition {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Practice Questions */
.practice-section {
    background: var(--background-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin: 40px 0;
}

.practice-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 25px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.practice-question {
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid var(--border-color);
}

.practice-question:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.question-text {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 15px;
}

.question-options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.question-option {
    display: flex;
    align-items: center;
    padding: 12px 15px;
    background: var(--background-dark);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.3s ease;
}

.question-option:hover {
    border-color: var(--primary-color);
}

.question-option input {
    margin-right: 12px;
}

.question-option.correct {
    border-color: var(--success-color);
    background: rgba(34, 197, 94, 0.1);
}

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

.question-feedback {
    margin-top: 15px;
    padding: 15px;
    border-radius: var(--radius-sm);
    display: none;
}

.question-feedback.show {
    display: block;
}

.question-feedback.correct {
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid var(--success-color);
    color: var(--success-color);
}

.question-feedback.incorrect {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--error-color);
    color: var(--error-color);
}

/* Summary Section */
.summary-section {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);
    border: 1px solid var(--primary-color);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin: 40px 0;
}

.summary-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.summary-list {
    list-style: none;
    padding: 0;
}

.summary-list li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    margin-bottom: 12px;
    color: var(--text-secondary);
}

.summary-list li::before {
    content: '✓';
    color: var(--success-color);
    font-weight: bold;
    flex-shrink: 0;
}

/* Navigation Buttons */
.lesson-navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
    gap: 20px;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 15px 25px;
    background: var(--background-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

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

.nav-btn.primary {
    background: var(--gradient-primary);
    border: none;
    color: white;
}

.nav-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

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

.complete-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 20px;
    background: var(--success-color);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.complete-btn:hover {
    background: #16a34a;
}

.complete-btn.completed {
    background: var(--background-light);
    color: var(--success-color);
    border: 1px solid var(--success-color);
}

/* Mobile Sidebar Toggle */
.sidebar-toggle {
    display: none;
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 200;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--gradient-primary);
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
}

/* Exam Styles */
.exam-container {
    max-width: 800px;
}

.exam-header {
    text-align: center;
    margin-bottom: 40px;
}

.exam-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.exam-description {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 25px;
}

.exam-info {
    display: flex;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.exam-info-item {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
}

.exam-questions {
    counter-reset: question;
}

.exam-question {
    background: var(--background-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin-bottom: 25px;
}

.exam-question-header {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 20px;
}

.exam-question-number {
    width: 36px;
    height: 36px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    flex-shrink: 0;
}

.exam-question-text {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
    line-height: 1.5;
}

.exam-question-image {
    margin: 20px 0;
    border-radius: var(--radius-md);
    overflow: hidden;
}

.exam-question-image img {
    width: 100%;
    display: block;
}

.exam-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.exam-option {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    background: var(--background-dark);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.3s ease;
}

.exam-option:hover {
    border-color: var(--primary-color);
}

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

.exam-option input {
    display: none;
}

.exam-option-letter {
    width: 28px;
    height: 28px;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    margin-right: 15px;
    flex-shrink: 0;
    font-size: 0.9rem;
}

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

.exam-submit {
    text-align: center;
    margin-top: 40px;
}

.exam-submit .btn {
    min-width: 200px;
}

/* Exam Results */
.exam-results {
    text-align: center;
    padding: 60px 40px;
    background: var(--background-medium);
    border-radius: var(--radius-lg);
    margin-top: 40px;
}

.results-icon {
    font-size: 5rem;
    margin-bottom: 20px;
}

.results-title {
    font-size: 2rem;
    margin-bottom: 10px;
}

.results-score {
    font-size: 4rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 20px;
}

.results-message {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 30px;
}

.results-details {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 30px;
}

.result-stat {
    text-align: center;
}

.result-stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.result-stat-label {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.result-stat-value.correct {
    color: var(--success-color);
}

.result-stat-value.incorrect {
    color: var(--error-color);
}

/* Responsive */
@media (max-width: 1024px) {
    .main-content {
        padding: 30px 40px;
    }

    .key-terms {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
        max-width: 100%;
        padding: 25px 20px;
    }

    .sidebar-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .lesson-main-title {
        font-size: 1.8rem;
    }

    .lesson-navigation {
        flex-direction: column;
    }

    .nav-btn {
        width: 100%;
        justify-content: center;
    }

    .exam-info {
        flex-direction: column;
        gap: 15px;
    }

    .results-details {
        flex-direction: column;
        gap: 20px;
    }
}