/* ============================================
   Tutorials Page - Custom Styles
   Two-column layout with PDF viewer + commentary
   ============================================ */

/* Page header adjustments */
.tutorials-header {
    margin: 2rem auto;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--color-border);
}

.tutorials-header h1 {
    font-family: var(--font-display);
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
    text-align: center;
}

.tutorials-header .intro-note {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    font-style: italic;
    max-width: 700px;
    line-height: 1.7;
    margin-top: 1rem;
    padding: 1rem 1.25rem;
    background: rgba(5, 150, 105, 0.05);
    border-left: 3px solid var(--color-accent-teaching);
    border-radius: 0 8px 8px 0;
}

/* Navigation sidebar for sheets */
.sheets-nav {
    top: 1rem;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 1.25rem;
    margin-bottom: 2rem;
}

.sheets-nav h3 {
    font-family: var(--font-display);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 0.75rem;
}

.sheets-nav-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    list-style: none;
}

.sheets-nav-list a {
    display: inline-block;
    padding: 0.4rem 0.75rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-text-muted);
    background: rgba(0, 0, 0, 0.03);
    border: 1px solid transparent;
    border-radius: 6px;
    text-decoration: none;
    transition: all var(--transition-smooth);
}

.sheets-nav-list a:hover {
    color: var(--color-accent-teaching);
    background: rgba(5, 150, 105, 0.08);
    border-color: rgba(5, 150, 105, 0.2);
}

/* Exercise Sheet Section */
.sheet-section {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 16px;
    margin-bottom: 2.5rem;
    overflow: hidden;
    transition: box-shadow var(--transition-smooth);
}

.sheet-section:hover {
    box-shadow: 0 8px 30px -12px rgba(0, 0, 0, 0.12);
}

/* Section header */
.sheet-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.25rem 1.5rem;
    background: linear-gradient(135deg, rgba(5, 150, 105, 0.06) 0%, rgba(5, 150, 105, 0.02) 100%);
    border-bottom: 1px solid var(--color-border);
}

.sheet-header h2 {
    font-family: var(--font-display);
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: -0.01em;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.6rem;
}

.sheet-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--color-accent-teaching);
    background: rgba(5, 150, 105, 0.12);
    border-radius: 8px;
}

.sheet-actions {
    display: flex;
    gap: 0.5rem;
}

.sheet-action-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.5rem 0.9rem;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--color-text-muted);
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    text-decoration: none;
    transition: all var(--transition-smooth);
    cursor: pointer;
}

.sheet-action-btn:hover {
    color: var(--color-accent-teaching);
    border-color: var(--color-accent-teaching);
    background: rgba(5, 150, 105, 0.05);
}

.sheet-action-btn svg {
    width: 14px;
    height: 14px;
}

/* Two-column layout */
.sheet-content {
    display: grid;
    grid-template-columns: minmax(320px, 420px) 1fr;
    min-height: 500px;
}

/* PDF Viewer column */
.pdf-viewer-column {
    border-right: 1px solid var(--color-border);
    background: #f5f5f5;
    position: relative;
}

.pdf-embed {
    width: 100%;
    height: 100%;
    min-height: 550px;
    border: none;
    display: block;
}

.pdf-fallback {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    min-height: 550px;
    padding: 2rem;
    text-align: center;
    color: var(--color-text-muted);
}

.pdf-fallback svg {
    width: 48px;
    height: 48px;
    margin-bottom: 1rem;
    opacity: 0.4;
}

.pdf-fallback p {
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

/* Commentary column */
.commentary-column {
    padding: 1.75rem 2rem;
}

.commentary-column h3 {
    font-family: var(--font-display);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--color-border);
}

.commentary-column p {
    font-size: 0.95rem;
    line-height: 1.75;
    color: var(--color-text);
    margin-bottom: 1rem;
}

.commentary-column p:last-child {
    margin-bottom: 0;
}

/* Minimal styling tag */
.tag-minimal {
    display: inline-block;
    padding: 0.2rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-text-muted);
    background: rgba(0, 0, 0, 0.05);
    border-radius: 4px;
    margin-bottom: 0.75rem;
}

/* Horizontal rule in commentary */
.commentary-column hr {
    border: none;
    height: 1px;
    background: var(--color-border);
    margin: 1.5rem 0;
}

/* LaTeX math styling */
.commentary-column .math-inline {
    font-family: 'Latin Modern Math', 'STIX Two Math', 'Times New Roman', serif;
    font-style: italic;
    padding: 0 0.15em;
}

/* Highlighted exercise notes */
.exercise-note {
    background: rgba(37, 99, 235, 0.05);
    border-left: 3px solid var(--color-accent-research);
    padding: 1rem 1.25rem;
    border-radius: 0 8px 8px 0;
    margin: 1rem 0;
}

.exercise-note p {
    margin: 0;
    font-size: 0.9rem;
}

/* Question callout */
.question-callout {
    background: rgba(245, 158, 11, 0.08);
    border-left: 3px solid #f59e0b;
    padding: 1rem 1.25rem;
    border-radius: 0 8px 8px 0;
    margin: 1rem 0;
}

.question-callout strong {
    color: #d97706;
}

/* Tutorial note link */
.tutorial-note-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    margin-top: 0.5rem;
    padding: 0.5rem 0.9rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-accent-teaching);
    background: rgba(5, 150, 105, 0.08);
    border-radius: 6px;
    text-decoration: none;
    transition: all var(--transition-smooth);
}

.tutorial-note-link:hover {
    background: rgba(5, 150, 105, 0.15);
    text-decoration: none;
}

/* Data table styling */
.data-table-wrapper {
    margin: 1.5rem 0;
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
}

.data-table th,
.data-table td {
    padding: 0.6rem 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

.data-table th {
    font-weight: 600;
    color: var(--color-text);
    background: rgba(0, 0, 0, 0.02);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

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

.data-table tbody tr:hover {
    background: rgba(5, 150, 105, 0.03);
}

/* Responsive adjustments */
@media (max-width: 1024px) {
    .sheet-content {
        grid-template-columns: 1fr;
    }
    
    .pdf-viewer-column {
        border-right: none;
        border-bottom: 1px solid var(--color-border);
    }
    
    .pdf-embed {
        min-height: 450px;
    }
    
    .pdf-fallback {
        min-height: 300px;
    }
    
    .commentary-column {
        padding: 1.5rem;
    }
}

@media (max-width: 640px) {
    .sheet-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .sheet-actions {
        width: 100%;
    }
    
    .sheet-action-btn {
        flex: 1;
        justify-content: center;
    }
    
    .sheets-nav-list a {
        padding: 0.35rem 0.6rem;
        font-size: 0.8rem;
    }
}

/* ============================================
   Feedback Row - Two column layout below content
   ============================================ */

.sheet-feedback-row {
    display: grid;
    grid-template-columns: minmax(280px, 380px) 1fr;
    border-top: 1px solid var(--color-border);
    background: var(--color-bg-secondary);
}

.workload-column {
    padding: 1.5rem;
    border-right: 1px solid var(--color-border);
}

.workload-column h4 {
    font-family: var(--font-display);
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.workload-column h4 svg {
    width: 18px;
    height: 18px;
    color: var(--color-accent-teaching);
}

.pie-chart-container {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.pie-chart {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    position: relative;
    flex-shrink: 0;
}

.pie-chart-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 50px;
    height: 50px;
    background: var(--color-bg-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    font-weight: 600;
    color: var(--color-text-muted);
    text-align: center;
    line-height: 1.2;
}

.pie-legend {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    font-size: 0.78rem;
}

.pie-legend-item {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--color-text-muted);
}

.pie-legend-color {
    width: 10px;
    height: 10px;
    border-radius: 2px;
    flex-shrink: 0;
}

.pie-legend-item span:last-child {
    opacity: 0.7;
    font-size: 0.72rem;
}

/* Color scheme for pie chart - pastel palette */
.color-1hr { background: #86efac; }   /* Mint green */
.color-2hrs { background: #93c5fd; }  /* Sky blue */
.color-3hrs { background: #fcd34d; }  /* Soft amber */
.color-4hrs { background: #c4b5fd; }  /* Lavender */
.color-5hrs { background: #f9a8d4; }  /* Pink */
.color-more { background: #94a3b8; }  /* Slate */

/* ============================================
   Student Feedback Column
   ============================================ */

.feedback-column {
    padding: 1.5rem 2rem;
}

.feedback-column h4 {
    font-family: var(--font-display);
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.feedback-column h4 svg {
    width: 18px;
    height: 18px;
    color: var(--color-accent-teaching);
}

.feedback-list {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.feedback-item {
    font-size: 0.88rem;
    line-height: 1.6;
    color: var(--color-text-muted);
    padding: 0.6rem 0.75rem 0.6rem 1.5rem;
    background: transparent;
    border-radius: 4px;
    position: relative;
}

.feedback-item::before {
    content: '"';
    position: absolute;
    top: 0.3rem;
    left: 0;
    font-size: 1.4rem;
    color: rgba(5, 150, 105, 0.35);
    font-family: Georgia, serif;
    line-height: 1;
}

.feedback-item p {
    margin: 0;
}

/* ============================================
   Summary Section Styles
   ============================================ */

.summary-section {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 16px;
    padding: 2rem;
    margin-bottom: 2.5rem;
}

.summary-section h2 {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1.5rem;
    text-align: center;
}

.summary-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.summary-pie-chart {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    position: relative;
    flex-shrink: 0;
}

.summary-pie-chart .pie-chart-center {
    width: 80px;
    height: 80px;
    font-size: 0.85rem;
}

.summary-legend {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    font-size: 0.9rem;
}

.summary-legend .pie-legend-item {
    font-size: 0.9rem;
}

.summary-stats {
    text-align: center;
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--color-border);
}

.summary-stats p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    margin: 0;
}

@media (max-width: 1024px) {
    .sheet-feedback-row {
        grid-template-columns: 1fr;
    }
    
    .workload-column {
        border-right: none;
        border-bottom: 1px solid var(--color-border);
    }
}

@media (max-width: 640px) {
    .pie-chart-container {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .summary-content {
        flex-direction: column;
    }
    
    .feedback-column {
        padding: 1.5rem;
    }
}