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

:root {
    /* Classic Modern Color Palette */
    --primary: #1a1a1a;
    --secondary: #2d2d2d;
    --accent: #4a5568;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #f1f3f5;
    --border: #e5e7eb;
    --border-light: #f3f4f6;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --primary: #ffffff;
    --secondary: #f3f4f6;
    --accent: #9ca3af;
    --text-primary: #f9fafb;
    --text-secondary: #d1d5db;
    --text-light: #9ca3af;
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
    --bg-tertiary: #374151;
    --border: #374151;
    --border-light: #4b5563;
}

body {
    font-family: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    -webkit-tap-highlight-color: transparent;
}

/* Touch-friendly improvements */
button, .pdf-card, .filter-btn, .recent-item, .action-btn {
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0.1);
    touch-action: manipulation;
}

.app-wrapper {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: var(--bg-primary);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    z-index: 100;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.sidebar-header {
    padding: 2rem 1.5rem;
    border-bottom: 1px solid var(--border);
    background: var(--bg-primary);
    position: sticky;
    top: 0;
    z-index: 10;
    backdrop-filter: blur(10px);
}

.logo {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    text-align: center;
}

.logo-text {
    font-family: 'Playfair Display', serif;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    text-align: center;
    letter-spacing: -0.5px;
}

.sidebar-nav {
    flex: 1;
    padding: 1.5rem 0;
    overflow-y: auto;
}

.nav-section {
    margin-bottom: 2rem;
    padding: 0 1.5rem;
}

.nav-title {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.nav-filters {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.filter-btn {
    padding: 0.875rem 1.125rem;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-weight: 500;
}

.filter-btn:hover {
    background: var(--bg-secondary);
    border-color: var(--accent);
    color: var(--text-primary);
    transform: translateX(4px);
}

.filter-btn.active {
    background: var(--bg-tertiary);
    border-color: var(--accent);
    color: var(--text-primary);
    font-weight: 600;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.filter-count {
    font-size: 0.75rem;
    color: var(--text-light);
    background: var(--bg-secondary);
    padding: 0.25rem 0.5rem;
    border-radius: 12px;
}

.recent-pdfs {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 300px;
    overflow-y: auto;
}

.recent-item {
    padding: 0.75rem;
    background: var(--bg-secondary);
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.recent-item:hover {
    background: var(--bg-tertiary);
    border-color: var(--border);
    transform: translateX(4px);
}

.recent-thumb {
    width: 40px;
    height: 50px;
    border-radius: 4px;
    object-fit: cover;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
}

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

.recent-name {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.recent-time {
    font-size: 0.75rem;
    color: var(--text-light);
}

.empty-state {
    font-size: 0.85rem;
    color: var(--text-light);
    text-align: center;
    padding: 1rem;
    font-style: italic;
}

.sidebar-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--border);
    background: var(--bg-secondary);
}

.stats-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.stat-item {
    text-align: center;
    padding: 1rem;
    background: var(--bg-primary);
    border-radius: 8px;
    border: 1px solid var(--border);
}

.stat-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    font-family: 'Playfair Display', serif;
}

.stat-label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 0.25rem;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 280px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    padding: 2.5rem 3rem;
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    backdrop-filter: blur(10px);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.page-title {
    font-family: 'Playfair Display', serif;
    font-size: 2.75rem;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -1.5px;
    line-height: 1.2;
}

.page-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.theme-toggle {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--bg-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    font-size: 1.25rem;
}

.theme-toggle:hover {
    background: var(--bg-tertiary);
    transform: rotate(15deg);
}

.search-container {
    margin-top: 1.5rem;
}

.search-wrapper {
    position: relative;
    max-width: 600px;
    display: flex;
    align-items: center;
}

.search-icon {
    position: absolute;
    left: 1rem;
    color: var(--text-light);
    pointer-events: none;
}

.search-input {
    width: 100%;
    padding: 1rem 3.5rem 1rem 3.5rem;
    font-size: 1rem;
    border: 2px solid var(--border);
    border-radius: 12px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: var(--transition);
    font-family: 'Source Sans Pro', sans-serif;
    font-weight: 400;
}

.search-input::placeholder {
    color: var(--text-light);
    opacity: 0.7;
}

.search-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(74, 85, 104, 0.08);
    background: var(--bg-primary);
}

.clear-search {
    position: absolute;
    right: 0.75rem;
    width: 32px;
    height: 32px;
    border: none;
    background: transparent;
    color: var(--text-light);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    transition: var(--transition);
}

.clear-search:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.content-area {
    flex: 1;
    padding: 3rem;
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
}

.sections-container {
    display: flex;
    flex-direction: column;
    gap: 4rem;
    animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.section {
    animation: fadeInUp 0.5s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section-header {
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.section-title {
    font-family: 'Playfair Display', serif;
    font-size: 2rem;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: baseline;
    gap: 0.75rem;
    margin-bottom: 0;
}

.section-count {
    font-size: 0.875rem;
    color: var(--text-light);
    font-weight: 400;
    font-family: 'Source Sans Pro', sans-serif;
}

.pdf-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.5rem;
}

.pdf-card {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
}

.pdf-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
    border-color: var(--accent);
}

.pdf-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.pdf-card:hover::before {
    opacity: 1;
}

.pdf-thumbnail {
    width: 100%;
    height: 280px;
    background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border);
}

.pdf-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.pdf-card:hover .pdf-thumbnail img {
    transform: scale(1.05);
}

.pdf-thumbnail-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--text-light);
    font-size: 4rem;
    opacity: 0.5;
}

.pdf-thumbnail-loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 48px;
    height: 48px;
    border: 4px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: translate(-50%, -50%) rotate(360deg); }
}

.pdf-info {
    padding: 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.pdf-name {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin-bottom: 0.75rem;
    min-height: 2.85rem;
}

.pdf-category {
    font-size: 0.75rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 500;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: var(--bg-primary);
    border-radius: 16px;
    width: 95%;
    max-width: 1400px;
    height: 90vh;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-xl);
    animation: modalSlideIn 0.3s ease-out;
    z-index: 1001;
    border: 1px solid var(--border);
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: scale(0.95) translateY(20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.modal-content:fullscreen {
    width: 100vw;
    height: 100vh;
    max-width: 100vw;
    max-height: 100vh;
    border-radius: 0;
    overflow: hidden;
}

.modal-content:fullscreen .pdf-viewer-wrapper {
    height: 100vh;
    overflow: hidden;
}

.modal-content:fullscreen .pdf-viewer-container {
    height: 100%;
    overflow: hidden;
}

.modal-content:fullscreen .pdf-canvas-container {
    height: 100%;
    overflow-y: auto;
    overflow-x: hidden;
    -webkit-overflow-scrolling: touch;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1.5rem;
    border-bottom: 1px solid var(--border);
    background: var(--bg-secondary);
    flex-shrink: 0;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: transform 0.3s ease, opacity 0.3s ease;
    transform: translateY(0);
    opacity: 1;
}

.modal-header.hidden {
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
}

.modal-content:hover .modal-header.hidden {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
}

.modal-title-section {
    flex: 1;
    min-width: 0;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.back-btn {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--bg-primary);
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    flex-shrink: 0;
}

.back-btn:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent);
    transform: translateX(-2px);
}

.title-content {
    flex: 1;
    min-width: 0;
}

.modal-title {
    font-family: 'Playfair Display', serif;
    font-size: 1.25rem;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 0.125rem;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    line-height: 1.3;
}

.modal-subtitle {
    font-size: 0.75rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    line-height: 1.2;
}

.modal-actions {
    display: flex;
    gap: 0.75rem;
}

.action-btn {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-family: 'Source Sans Pro', sans-serif;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg-primary);
    color: var(--text-primary);
}

.action-btn:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent);
    transform: translateY(-1px);
}

.fullscreen-btn {
    background: var(--bg-primary);
}

.close-btn {
    background: var(--bg-primary);
}

.pdf-viewer-container {
    flex: 1;
    overflow: hidden;
    position: relative;
    background: #525252;
    display: flex;
    flex-direction: column;
}

/* PDF controls removed - clean minimal design */

.pdf-canvas-container {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    position: relative;
    background: #1a1a1a;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0;
    min-height: 0;
    -webkit-overflow-scrolling: touch;
    scroll-behavior: smooth;
}

#pdfCanvas,
.pdf-page-canvas {
    max-width: 100%;
    width: 100%;
    height: auto;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.5);
    background: white;
    margin: 0;
    display: block;
    image-rendering: -webkit-optimize-contrast;
    image-rendering: crisp-edges;
}

.pdf-page-canvas {
    margin-bottom: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.pdf-page-canvas:first-child {
    border-top: none;
}

.pdf-loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: white;
    z-index: 10;
}

.pdf-loading .spinner {
    margin: 0 auto 1rem;
}

.pdf-loading p {
    color: white;
    font-size: 1.1rem;
}

.loading-indicator {
    text-align: center;
    padding: 4rem;
    color: var(--text-secondary);
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 1rem;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    width: 44px;
    height: 44px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--bg-secondary);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    color: var(--text-primary);
    margin-right: 1rem;
}

.mobile-menu-btn:hover {
    background: var(--bg-tertiary);
}

.mobile-menu-btn svg {
    width: 20px;
    height: 20px;
}

/* Sidebar Overlay */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 99;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.sidebar-overlay.active {
    display: block;
    opacity: 1;
}

/* Responsive */
@media (max-width: 1024px) {
    .sidebar {
        width: 260px;
    }
    
    .main-content {
        margin-left: 260px;
    }
    
    .main-header {
        padding: 1.5rem 2rem;
    }
    
    .content-area {
        padding: 1.5rem 2rem;
    }
    
    .pdf-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 1.25rem;
    }
}

@media (max-width: 768px) {
    .mobile-menu-btn {
        display: flex;
    }
    
    .sidebar {
        width: 280px;
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        z-index: 100;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .sidebar-overlay.active {
        display: block;
    }
    
    .main-content {
        margin-left: 0;
        width: 100%;
    }
    
    .header-top {
        display: flex;
        align-items: center;
        gap: 0.75rem;
    }
    
    .page-title {
        font-size: 1.5rem;
        flex: 1;
        min-width: 0;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
    }
    
    .theme-toggle {
        width: 40px;
        height: 40px;
        flex-shrink: 0;
    }
    
    .main-header {
        padding: 1.25rem 1rem;
    }
    
    .page-subtitle {
        font-size: 0.9rem;
        margin-bottom: 1.25rem;
    }
    
    .search-wrapper {
        max-width: 100%;
    }
    
    .search-input {
        padding: 0.875rem 3rem 0.875rem 3rem;
        font-size: 0.95rem;
    }
    
    .content-area {
        padding: 1.5rem 1rem;
    }
    
    .sections-container {
        gap: 2.5rem;
    }
    
    .section {
        margin-bottom: 0;
    }
    
    .section-header {
        margin-bottom: 1.25rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .pdf-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 1rem;
    }
    
    .pdf-thumbnail {
        height: 220px;
    }
    
    .pdf-info {
        padding: 1.25rem;
    }
    
    .pdf-name {
        font-size: 0.9rem;
        min-height: 2.7rem;
    }
    
    .pdf-category {
        font-size: 0.7rem;
    }
    
    .modal-content {
        width: 100%;
        height: 100vh;
        max-height: 100vh;
        border-radius: 0;
    }
    
    .modal-header {
        padding: 0.5rem 0.75rem;
        flex-direction: row;
        gap: 0.5rem;
        align-items: center;
    }
    
    .modal-title-section {
        gap: 0.5rem;
    }
    
    .back-btn {
        width: 36px;
        height: 36px;
        display: flex;
    }
    
    .back-btn svg {
        width: 18px;
        height: 18px;
    }
    
    .modal-title {
        font-size: 0.95rem;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    
    .modal-subtitle {
        display: none;
    }
    
    .modal-actions {
        display: flex;
        gap: 0.5rem;
        flex-shrink: 0;
    }
    
    .action-btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.75rem;
        gap: 0.375rem;
    }
    
    .action-btn svg {
        width: 14px;
        height: 14px;
    }
    
    .action-btn span {
        display: none;
    }
    
    .action-btn svg {
        margin: 0;
    }
    
    .pdf-canvas-container {
        padding: 1rem;
    }
    
    #pdfCanvas {
        max-width: 100%;
    }
    
    .sidebar-header {
        padding: 1.5rem 1.25rem;
    }
    
    .logo {
        font-size: 2.5rem;
    }
    
    .logo-text {
        font-size: 1.25rem;
    }
    
    .nav-section {
        padding: 0 1.25rem;
        margin-bottom: 1.5rem;
    }
    
    .filter-btn {
        padding: 0.75rem 1rem;
        font-size: 0.85rem;
    }
    
    .recent-pdfs {
        max-height: 250px;
    }
    
    .recent-item {
        padding: 0.625rem;
    }
    
    .recent-thumb {
        width: 35px;
        height: 45px;
    }
    
    .recent-name {
        font-size: 0.8rem;
    }
    
    .recent-time {
        font-size: 0.7rem;
    }
    
    .sidebar-footer {
        padding: 1.25rem;
    }
    
    .stats-card {
        gap: 0.75rem;
    }
    
    .stat-item {
        padding: 0.875rem;
    }
    
    .stat-number {
        font-size: 1.25rem;
    }
    
    .stat-label {
        font-size: 0.7rem;
    }
}

@media (max-width: 480px) {
    .page-title {
        font-size: 1.25rem;
    }
    
    .main-header {
        padding: 1rem 0.875rem;
    }
    
    .content-area {
        padding: 1.25rem 0.875rem;
    }
    
    .sections-container {
        gap: 2rem;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .pdf-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
        gap: 0.875rem;
    }
    
    .pdf-thumbnail {
        height: 200px;
    }
    
    .pdf-info {
        padding: 1rem;
    }
    
    .pdf-name {
        font-size: 0.85rem;
        min-height: 2.55rem;
        margin-bottom: 0.5rem;
    }
    
    .pdf-category {
        font-size: 0.65rem;
    }
    
    .search-input {
        padding: 0.75rem 2.75rem 0.75rem 2.75rem;
        font-size: 0.9rem;
    }
    
    .search-icon {
        left: 0.875rem;
        width: 18px;
        height: 18px;
    }
    
    .clear-search {
        right: 0.625rem;
        width: 28px;
        height: 28px;
    }
    
    .modal-header {
        padding: 0.375rem 0.5rem;
    }
    
    .back-btn {
        width: 32px;
        height: 32px;
    }
    
    .back-btn svg {
        width: 16px;
        height: 16px;
    }
    
    .modal-title {
        font-size: 0.85rem;
    }
    
    .modal-subtitle {
        display: none;
    }
    
    .action-btn {
        padding: 0.375rem 0.5rem;
        font-size: 0.7rem;
        min-height: 32px;
        gap: 0.25rem;
    }
    
    .action-btn svg {
        width: 12px;
        height: 12px;
    }
    
    .action-btn span {
        display: none;
    }
    
    .pdf-canvas-container {
        padding: 0.75rem;
    }
    
    .sidebar {
        width: 100%;
        max-width: 320px;
    }
    
    .mobile-menu-btn {
        width: 44px;
        height: 44px;
        margin-right: 0.75rem;
        min-width: 44px;
    }
    
    .theme-toggle {
        width: 44px;
        height: 44px;
        min-width: 44px;
    }
    
    .filter-btn {
        min-height: 44px;
    }
    
    .pdf-card {
        min-height: 320px;
    }
}

/* Content Notice */
.content-notice {
    margin-top: 4rem;
    padding: 2rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 12px;
    display: flex;
    gap: 1.5rem;
    box-shadow: var(--shadow-sm);
    animation: fadeInUp 0.6s ease-out;
}

.notice-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
    opacity: 0.8;
}

.notice-content {
    flex: 1;
}

.notice-title {
    font-family: 'Playfair Display', serif;
    font-size: 1.5rem;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 1rem;
}

.notice-text {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 1rem;
}

.notice-text:last-of-type {
    margin-bottom: 0;
}

.notice-small {
    font-size: 0.85rem;
    color: var(--text-light);
    font-style: italic;
}

.notice-link {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border-bottom: 1px solid transparent;
}

.notice-link:hover {
    color: var(--text-primary);
    border-bottom-color: var(--accent);
}

@media (max-width: 768px) {
    .content-notice {
        flex-direction: column;
        padding: 1.5rem;
        gap: 1rem;
        margin-top: 3rem;
    }
    
    .notice-icon {
        font-size: 2rem;
        text-align: center;
    }
    
    .notice-title {
        font-size: 1.25rem;
        text-align: center;
    }
    
    .notice-text {
        font-size: 0.9rem;
        text-align: center;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}

/* Footer */
.site-footer {
    margin-top: 4rem;
    padding: 2rem 0;
    border-top: 1px solid var(--border);
    background: var(--bg-primary);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.footer-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.footer-developer-section {
    display: flex;
    align-items: center;
}

.footer-developer-text {
    margin: 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.footer-by {
    color: var(--text-light);
    font-weight: 400;
}

.developer-name-link {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

.developer-name {
    color: var(--accent);
    font-weight: 600;
    font-size: 1rem;
    font-family: 'Source Sans Pro', sans-serif;
    transition: var(--transition);
    position: relative;
}

.developer-name-link:hover .developer-name {
    color: var(--text-primary);
}

.developer-name-link:hover {
    transform: translateY(-1px);
}

.developer-name::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s ease;
}

.developer-name-link:hover .developer-name::after {
    width: 100%;
}

.footer-divider {
    width: 1px;
    height: 24px;
    background: var(--border);
    opacity: 0.5;
}

.footer-social-section {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.social-icon-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 8px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.social-icon-link::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--accent);
    transform: translate(-50%, -50%);
    transition: width 0.4s ease, height 0.4s ease;
    opacity: 0.1;
}

.social-icon-link:hover::before {
    width: 100%;
    height: 100%;
    opacity: 0.15;
}

.social-icon-link:hover {
    color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.2);
}

.social-icon-link svg {
    position: relative;
    z-index: 1;
    transition: transform 0.3s ease;
}

.social-icon-link:hover svg {
    transform: scale(1.1);
}

@media (max-width: 768px) {
    .site-footer {
        margin-top: 3rem;
        padding: 1.5rem 0;
    }
    
    .footer-content {
        padding: 0 1rem;
    }
    
    .footer-wrapper {
        flex-direction: column;
        gap: 1rem;
    }
    
    .footer-divider {
        width: 60px;
        height: 1px;
        margin: 0 auto;
    }
    
    .footer-developer-text {
        justify-content: center;
        text-align: center;
        font-size: 0.9rem;
    }
    
    .developer-name {
        font-size: 0.95rem;
    }
    
    .footer-social-section {
        gap: 0.625rem;
    }
    
    .social-icon-link {
        width: 44px;
        height: 44px;
    }
    
    .social-icon-link svg {
        width: 20px;
        height: 20px;
    }
}

@media (max-width: 480px) {
    .site-footer {
        padding: 1.25rem 0;
    }
    
    .footer-wrapper {
        gap: 0.875rem;
    }
    
    .footer-developer-text {
        font-size: 0.85rem;
        gap: 0.375rem;
    }
    
    .developer-name {
        font-size: 0.9rem;
    }
    
    .social-icon-link {
        width: 42px;
        height: 42px;
    }
}