/* Cheat sheet pages — handwritten notes + interview focus */
.cheat-sheet-page {
    font-family: 'Inter', sans-serif;
    background: #f4f1ea;
    color: #1e293b;
    min-height: 100vh;
    padding-bottom: 3rem;
}

.cs-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 1.5rem;
}

.cs-breadcrumb {
    font-size: 0.85rem;
    color: #64748b;
    margin-bottom: 1rem;
}

.cs-breadcrumb a {
    color: #2563eb;
    text-decoration: none;
}

.cs-breadcrumb a:hover { text-decoration: underline; }

.cs-hero {
    margin-bottom: 1.5rem;
}

.cs-category-badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 0.3rem 0.75rem;
    border-radius: 50px;
    margin-bottom: 0.5rem;
}

.cs-category-badge.ai { background: #ede9fe; color: #6d28d9; }
.cs-category-badge.system-design { background: #dbeafe; color: #1d4ed8; }
.cs-category-badge.java { background: #ffedd5; color: #c2410c; }
.cs-category-badge.dsa { background: #dcfce7; color: #15803d; }
.cs-category-badge.behaviour { background: #fce7f3; color: #be185d; }

.cs-title {
    font-size: clamp(1.75rem, 4vw, 2.35rem);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 0.5rem;
}

.cs-subtitle {
    color: #64748b;
    font-size: 1.05rem;
    max-width: 640px;
}

.cs-interview-tip {
    background: linear-gradient(135deg, #fef3c7, #fde68a);
    border: 2px dashed #f59e0b;
    border-radius: 12px;
    padding: 1rem 1.25rem;
    margin: 1.25rem 0;
    font-family: 'Kalam', cursive;
    font-size: 1.05rem;
    line-height: 1.5;
}

.cs-interview-tip strong {
    font-family: 'Inter', sans-serif;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #b45309;
    display: block;
    margin-bottom: 0.35rem;
}

/* Paper note blocks */
.cs-paper {
    background: #fffef8;
    border: 1px solid #e7e0d0;
    border-radius: 4px;
    box-shadow: 2px 3px 12px rgba(0, 0, 0, 0.06), 0 0 0 1px rgba(0, 0, 0, 0.02);
    padding: 1.75rem 1.5rem;
    margin-bottom: 1.5rem;
    position: relative;
    background-image:
        repeating-linear-gradient(
            transparent,
            transparent 27px,
            #e8e4dc 28px
        );
    background-position: 0 12px;
}

.cs-paper::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(#f87171, #fb923c, #fbbf24);
    border-radius: 4px 0 0 4px;
}

.cs-section-title {
    font-family: 'Caveat', cursive;
    font-size: 1.65rem;
    font-weight: 700;
    color: #1e40af;
    margin: 1.25rem 0 0.75rem;
    padding-top: 0.5rem;
}

.cs-section-title:first-child { margin-top: 0; }

.cs-note {
    font-family: 'Kalam', cursive;
    font-size: 1.08rem;
    line-height: 1.65;
    color: #334155;
    margin-bottom: 0.75rem;
}

.cs-note ul, .cs-note ol {
    margin: 0.5rem 0 0.75rem 1.25rem;
}

.cs-note li { margin-bottom: 0.35rem; }

.cs-note strong {
    color: #0f172a;
    font-weight: 700;
}

/* Tables */
.cs-table-wrap {
    overflow-x: auto;
    margin: 1rem 0;
    border-radius: 8px;
    border: 1px solid #e2e8f0;
    background: white;
}

.cs-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

.cs-table th {
    background: #f1f5f9;
    font-weight: 600;
    text-align: left;
    padding: 0.65rem 0.85rem;
    border-bottom: 2px solid #e2e8f0;
}

.cs-table td {
    padding: 0.6rem 0.85rem;
    border-bottom: 1px solid #f1f5f9;
    vertical-align: top;
}

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

/* Diagrams */
.cs-diagram {
    background: white;
    border: 2px solid #cbd5e1;
    border-radius: 12px;
    padding: 1.25rem;
    margin: 1.25rem 0;
    font-family: 'Inter', sans-serif;
}

.cs-diagram-title {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: #64748b;
    margin-bottom: 1rem;
    text-align: center;
}

.cs-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.cs-box {
    background: #eff6ff;
    border: 2px solid #3b82f6;
    border-radius: 8px;
    padding: 0.6rem 1rem;
    font-size: 0.85rem;
    font-weight: 600;
    text-align: center;
    min-width: 90px;
}

.cs-box.green { background: #ecfdf5; border-color: #10b981; }
.cs-box.purple { background: #f5f3ff; border-color: #8b5cf6; }
.cs-box.orange { background: #fff7ed; border-color: #f97316; }
.cs-box.gray { background: #f8fafc; border-color: #94a3b8; }

.cs-arrow {
    color: #94a3b8;
    font-weight: 700;
    font-size: 1.1rem;
}

.cs-stack {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    align-items: center;
}

.cs-layer-diagram {
    display: grid;
    gap: 0.5rem;
    max-width: 480px;
    margin: 0 auto;
}

.cs-layer {
    padding: 0.75rem 1rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.88rem;
    text-align: center;
    border: 2px solid;
}

.cs-layer.l1 { background: #dbeafe; border-color: #2563eb; }
.cs-layer.l2 { background: #e0e7ff; border-color: #4f46e5; }
.cs-layer.l3 { background: #ede9fe; border-color: #7c3aed; }
.cs-layer.l4 { background: #f3e8ff; border-color: #9333ea; }

.cs-roadmap {
    display: flex;
    flex-direction: column;
    gap: 0;
    margin: 1rem 0;
}

.cs-roadmap-step {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
    padding: 0.75rem 0;
    border-left: 3px solid #cbd5e1;
    margin-left: 1rem;
    padding-left: 1.25rem;
    position: relative;
}

.cs-roadmap-step::before {
    content: '';
    position: absolute;
    left: -8px;
    top: 1rem;
    width: 14px;
    height: 14px;
    background: #2563eb;
    border-radius: 50%;
    border: 3px solid white;
    box-shadow: 0 0 0 2px #2563eb;
}

.cs-roadmap-step h4 {
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    margin-bottom: 0.25rem;
}

.cs-roadmap-step p {
    font-family: 'Kalam', cursive;
    font-size: 0.95rem;
    color: #475569;
    margin: 0;
}

.cs-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin: 0.75rem 0;
}

.cs-tag {
    font-family: 'Inter', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.25rem 0.6rem;
    background: #f1f5f9;
    border-radius: 50px;
    color: #475569;
}

.cs-related {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 2px dashed #e2e8f0;
}

.cs-related h3 {
    font-size: 1rem;
    margin-bottom: 0.75rem;
}

.cs-related-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.cs-related-links a {
    font-size: 0.85rem;
    color: #2563eb;
    text-decoration: none;
    padding: 0.4rem 0.85rem;
    border: 1px solid #e2e8f0;
    border-radius: 50px;
    background: white;
}

.cs-related-links a:hover {
    border-color: #2563eb;
    background: #eff6ff;
}

.cs-category-badge.data-engineering { background: #cffafe; color: #0e7490; }

/* Print / PDF actions */
.cs-actions {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.cs-print-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.55rem 1.1rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 50px;
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    box-shadow: 0 2px 8px rgba(37, 99, 235, 0.25);
}

.cs-print-btn:hover {
    background: #1d4ed8;
    transform: translateY(-1px);
}

.cs-print-hint {
    font-size: 0.8rem;
    color: #64748b;
}

/* YouTube thumbnail cards */
.cs-youtube {
    margin-top: 2rem;
    padding: 1.5rem;
    background: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(15, 23, 42, 0.06);
}

.cs-youtube-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.cs-youtube-header h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #0f172a;
}

.cs-youtube-header h3 .fab {
    color: #ef4444;
    font-size: 1.25rem;
}

.cs-youtube-channel-link {
    font-size: 0.85rem;
    font-weight: 600;
    color: #2563eb;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.cs-youtube-channel-link:hover {
    color: #1d4ed8;
    text-decoration: underline;
}

.cs-youtube-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.25rem;
}

.cs-video-card {
    display: block;
    text-decoration: none;
    color: inherit;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid #e2e8f0;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.cs-video-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 28px rgba(37, 99, 235, 0.12);
    border-color: #93c5fd;
}

.cs-video-thumb {
    position: relative;
    aspect-ratio: 16 / 9;
    background: #1e293b;
    overflow: hidden;
}

.cs-video-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.35s ease;
}

.cs-video-card:hover .cs-video-thumb img {
    transform: scale(1.05);
}

.cs-video-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.55) 0%, transparent 50%);
    opacity: 0.85;
    transition: opacity 0.2s ease;
}

.cs-video-card:hover .cs-video-overlay {
    opacity: 1;
}

.cs-video-play {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 48px;
    height: 48px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ef4444;
    font-size: 1rem;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
    transition: transform 0.2s ease, background 0.2s ease;
}

.cs-video-card:hover .cs-video-play {
    transform: translate(-50%, -50%) scale(1.1);
    background: #fff;
}

.cs-video-badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background: rgba(15, 23, 42, 0.88);
    color: white;
    font-size: 0.68rem;
    font-weight: 700;
    padding: 0.25rem 0.55rem;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    backdrop-filter: blur(4px);
}

.cs-video-meta {
    padding: 0.85rem 1rem 1rem;
}

.cs-video-title {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: #0f172a;
    line-height: 1.35;
    margin-bottom: 0.35rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.cs-video-channel {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    font-size: 0.78rem;
    color: #64748b;
    font-weight: 500;
}

.cs-video-channel .fab {
    color: #ef4444;
    font-size: 0.85rem;
}

@media (max-width: 640px) {
    .cs-youtube-grid {
        grid-template-columns: 1fr;
    }
}

/* Print styles */
@media print {
    .site-header,
    .cs-actions,
    .cs-breadcrumb,
    .cs-related,
    .cs-print-hint {
        display: none !important;
    }

    body.has-site-nav {
        padding-top: 0 !important;
    }

    .cheat-sheet-page {
        background: white !important;
    }

    .cs-paper {
        box-shadow: none;
        break-inside: avoid;
        page-break-inside: avoid;
        border: 1px solid #ccc;
        margin-bottom: 1rem;
    }

    .cs-container {
        max-width: 100%;
        padding: 0;
    }

    .cs-diagram,
    .cs-table-wrap {
        break-inside: avoid;
    }

    a[href]::after {
        content: none;
    }

    .cs-youtube {
        break-inside: avoid;
    }

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

    .cs-video-card {
        break-inside: avoid;
        box-shadow: none;
    }

    .cs-video-card:hover {
        transform: none;
    }

    .cs-video-play {
        display: none;
    }
}

/* Hub page */
.cs-hub-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.25rem;
    margin-top: 1.5rem;
}

.cs-hub-card {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 1.25rem;
    transition: all 0.2s ease;
}

.cs-hub-card:hover {
    border-color: #2563eb;
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.1);
}

.cs-hub-card h2 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
}

.cs-hub-card ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.cs-hub-card li {
    margin-bottom: 0.5rem;
}

.cs-hub-card a {
    color: #2563eb;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
}

.cs-hub-card a:hover { text-decoration: underline; }

/* Table of contents */
.cs-toc {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 1.15rem 1.35rem;
    margin: 1.25rem 0 1.75rem;
}

.cs-toc-title {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #64748b;
    margin-bottom: 0.65rem;
}

.cs-toc ol {
    margin: 0;
    padding-left: 1.25rem;
    columns: 2;
    column-gap: 1.5rem;
}

.cs-toc li {
    margin-bottom: 0.35rem;
    font-size: 0.88rem;
    break-inside: avoid;
}

.cs-toc a {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
}

.cs-toc a:hover { text-decoration: underline; }

/* Architecture grid diagrams */
.cs-arch-grid {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin: 0.5rem 0;
}

.cs-arch-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.cs-arch-cell {
    flex: 1;
    min-width: 120px;
    max-width: 220px;
    padding: 0.65rem 0.85rem;
    border: 2px solid #94a3b8;
    border-radius: 8px;
    background: #f8fafc;
    font-size: 0.82rem;
    font-weight: 600;
    text-align: center;
    line-height: 1.35;
}

.cs-arch-cell.primary { background: #eff6ff; border-color: #3b82f6; }
.cs-arch-cell.data { background: #ecfdf5; border-color: #10b981; }
.cs-arch-cell.queue { background: #fff7ed; border-color: #f97316; }
.cs-arch-cell.client { background: #f1f5f9; border-color: #64748b; }

.cs-subheading {
    font-family: 'Inter', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: #1e40af;
    margin: 1.25rem 0 0.5rem;
}

.cs-checklist {
    list-style: none;
    margin: 0.75rem 0;
    padding: 0;
}

.cs-checklist li {
    position: relative;
    padding: 0.45rem 0 0.45rem 1.75rem;
    font-family: 'Kalam', cursive;
    font-size: 1.05rem;
    line-height: 1.45;
    border-bottom: 1px dashed #e2e8f0;
}

.cs-checklist li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #10b981;
    font-weight: 700;
    font-family: 'Inter', sans-serif;
}

.cs-code-block {
    background: #1e293b;
    color: #e2e8f0;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.82rem;
    line-height: 1.55;
    padding: 1rem 1.15rem;
    border-radius: 8px;
    margin: 1rem 0;
    overflow-x: auto;
    white-space: pre-wrap;
}

/* AI practice prompt box */
.cs-prompt-box {
    background: linear-gradient(135deg, #f8fafc 0%, #eef2ff 100%);
    border: 2px solid #c7d2fe;
    border-radius: 16px;
    padding: 1.5rem 1.5rem 1.25rem;
    margin: 2rem 0 1.5rem;
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.12);
}

.cs-prompt-header h3 {
    font-size: 1.15rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 0.35rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.cs-prompt-header h3 i {
    color: #6366f1;
}

.cs-prompt-header p {
    font-size: 0.9rem;
    color: #64748b;
    margin-bottom: 1rem;
}

.cs-prompt-preview {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    padding: 1rem 1.15rem;
    font-size: 0.88rem;
    line-height: 1.65;
    color: #334155;
    max-height: 160px;
    overflow-y: auto;
    margin-bottom: 1rem;
    font-family: 'Inter', sans-serif;
}

.cs-prompt-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
}

.cs-prompt-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.65rem 1.15rem;
    border-radius: 50px;
    font-size: 0.88rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.cs-prompt-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
}

.cs-prompt-gpt {
    background: #10a37f;
    color: white;
}

.cs-prompt-claude {
    background: #d97757;
    color: white;
}

.cs-prompt-copy {
    background: white;
    color: #475569;
    border: 1px solid #e2e8f0;
}

.cs-container {
    max-width: 960px;
}

@media (max-width: 640px) {
    .cs-paper { padding: 1.25rem 1rem; }
    .cs-flow { flex-direction: column; }
    .cs-arrow { transform: rotate(90deg); }
    .cs-toc ol { columns: 1; }
    .cs-arch-cell { min-width: 100%; max-width: 100%; }
    .cs-prompt-actions { flex-direction: column; }
    .cs-prompt-btn { justify-content: center; width: 100%; }
}