/* Enhanced PDF Viewer CSS - Fully Responsive */
/* Import global design system variables */
@import url('./global-variables.css');
@import url('./utility-classes.css');

/* ========================================
   ROOT VARIABLES AND THEME
   ======================================== */

   
:root {
    /* Colors */
    --success-color: #16a34a;
    --warning-color: #d97706;
    --error-color: #dc2626;
    --info-color: #0ea5e9;
    /* Background colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-elevated: #ffffff;
    --bg-overlay: rgba(0, 0, 0, 0.5);
    /* Text colors */
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --text-inverse: #ffffff;
    /* Border colors */
    --border-light: #e2e8f0;
    --border-base: #cbd5e1;
    --border-strong: #94a3b8;
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-base: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-12: 3rem;
    /* Typography */
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    /* Layout */
    --header-height: 70px;
    --controls-height: 60px;
    --sidebar-width: 280px;
    --sidebar-width-mobile: 240px;
    /* Border radius */
    --radius-sm: 0.25rem;
    --radius-base: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 200ms ease-in-out;
    --transition-slow: 300ms ease-in-out;
    /* Z-index layers */
    --z-sticky: 10;
    --z-dropdown: 100;
    --z-modal: 1000;
    --z-tooltip: 1010;
}

/* ========================================
   RESET AND BASE STYLES
   ======================================== */

* {
    box-sizing: border-box;
}

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    margin: 0;
    padding: 0;
    overflow-x: hidden;
    display: flex;
    flex-direction: column;
    height: 100vh;
}

/* ========================================
   HEADER STYLES
   ======================================== */

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--spacing-6);
    height: var(--header-height);
    background-color: var(--bg-elevated);
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-sm);
    position: relative;
    z-index: var(--z-sticky);
    flex-shrink: 0;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-4);
    flex: 1;
    min-width: 0;
}

.logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    flex-shrink: 0;
}

    .logo-link img {
        width: 50px;
        height: 50px;
        object-fit: contain;
        border-radius: var(--radius-md);
    }

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

.document-title {
    margin: 0;
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

    .document-title i {
        color: var(--primary-color);
        flex-shrink: 0;
    }

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    flex-shrink: 0;
}

/* ========================================
   CONTROLS BAR
   ======================================== */

.controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-3) var(--spacing-6);
    height: var(--controls-height);
    background-color: var(--bg-elevated);
    border-bottom: 1px solid var(--border-light);
    flex-shrink: 0;
    gap: var(--spacing-4);
}

.controls-group {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
}

.controls-left {
    flex: 1;
    justify-content: flex-start;
}

.controls-center {
    flex: 0 0 auto;
}

.controls-right {
    flex: 1;
    justify-content: flex-end;
}

/* ========================================
   MODERN BUTTON SYSTEM
   ======================================== */

.btn-modern {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-2) var(--spacing-4);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    user-select: none;
    position: relative;
    overflow: hidden;
}

    .btn-modern:focus {
        outline: none;
        box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    }

    .btn-modern:disabled {
        opacity: 0.5;
        cursor: not-allowed;
        pointer-events: none;
    }

    /* Button variants */
    .btn-modern.btn-primary {
        background-color: var(--primary-color);
        color: var(--text-inverse);
        box-shadow: var(--shadow-sm);
    }

        .btn-modern.btn-primary:hover:not(:disabled) {
            background-color: var(--primary-900);
            transform: translateY(-1px);
            box-shadow: var(--shadow-md);
        }

    .btn-modern.btn-secondary {
        background-color: var(--bg-secondary);
        color: var(--text-primary);
        border: 1px solid var(--border-base);
    }

        .btn-modern.btn-secondary:hover:not(:disabled) {
            background-color: var(--secondary-color);
            color: var(--text-inverse);
            border-color: var(--secondary-color);
        }

    .btn-modern.btn-outline {
        background-color: transparent;
        color: var(--text-primary);
        border: 1px solid var(--border-base);
    }

        .btn-modern.btn-outline:hover:not(:disabled) {
            background-color: var(--bg-secondary);
            border-color: var(--border-strong);
        }

    .btn-modern.btn-sm {
        padding: var(--spacing-1) var(--spacing-3);
        font-size: var(--font-size-xs);
    }

/* ========================================
   PAGE NAVIGATION
   ======================================== */

.page-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2);
    box-shadow: var(--shadow-sm);
}

.page-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.page-input {
    width: 60px;
    padding: var(--spacing-1) var(--spacing-2);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-base);
    text-align: center;
    font-size: var(--font-size-sm);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition-fast);
}

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

/* ========================================
   SEARCH FUNCTIONALITY
   ======================================== */

.search-container {
    position: relative;
}

.search-input-container {
    position: absolute;
    top: calc(100% + var(--spacing-2));
    left: 0;
    min-width: 320px;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-4);
    box-shadow: var(--shadow-lg);
    z-index: var(--z-dropdown);
    display: none;
    flex-direction: column;
    gap: var(--spacing-3);
}

    .search-input-container.show {
        display: flex;
    }

.search-input-group {
    display: flex;
    gap: var(--spacing-2);
    align-items: center;
}

.search-input {
    flex: 1;
    padding: var(--spacing-2) var(--spacing-3);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-base);
    font-size: var(--font-size-sm);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition-fast);
}

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

    .search-input::placeholder {
        color: var(--text-muted);
    }

.search-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-3);
}

.search-navigation {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
}

.search-nav-btn {
    width: 32px;
    height: 32px;
    border: none;
    border-radius: var(--radius-full);
    background-color: var(--primary-color);
    color: var(--text-inverse);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition-fast);
}

    .search-nav-btn:hover {
        background-color: var(--primary-900);
        transform: scale(1.05);
    }

.search-info {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    font-weight: var(--font-weight-medium);
    min-width: 60px;
    text-align: center;
}

.search-close-btn {
    position: absolute;
    top: var(--spacing-2);
    right: var(--spacing-2);
    width: 24px;
    height: 24px;
    border: none;
    background: none;
    color: var(--text-muted);
    cursor: pointer;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
}

    .search-close-btn:hover {
        background-color: var(--bg-secondary);
        color: var(--text-primary);
    }

/* ========================================
   ZOOM CONTROLS
   ======================================== */

.zoom-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-1);
    box-shadow: var(--shadow-sm);
}

.zoom-level {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--text-secondary);
    min-width: 50px;
    text-align: center;
}

/* ========================================
   MAIN CONTENT LAYOUT
   ======================================== */

.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
}

/* ========================================
   SIDEBAR
   ======================================== */

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-elevated);
    border-right: 1px solid var(--border-light);
    display: flex;
    flex-direction: column;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
    z-index: var(--z-sticky);
}

    .sidebar.hidden {
        width: 0;
        border-right: none;
        box-shadow: none;
        overflow: hidden;
        display: none;
    }

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-4);
    border-bottom: 1px solid var(--border-light);
    background-color: var(--bg-secondary);
}

.sidebar-title {
    margin: 0;
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
}

.sidebar-close {
    display: none;
    width: 32px;
    height: 32px;
    border: none;
    background: none;
    color: var(--text-muted);
    cursor: pointer;
    border-radius: var(--radius-full);
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
}

    .sidebar-close:hover {
        background-color: var(--bg-primary);
        color: var(--text-primary);
    }

.sidebar-content {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-2);
    scrollbar-width: thin;
    scrollbar-color: var(--border-base) transparent;
}

    .sidebar-content::-webkit-scrollbar {
        width: 6px;
    }

    .sidebar-content::-webkit-scrollbar-track {
        background: transparent;
    }

    .sidebar-content::-webkit-scrollbar-thumb {
        background: var(--border-base);
        border-radius: var(--radius-full);
    }

        .sidebar-content::-webkit-scrollbar-thumb:hover {
            background: var(--border-strong);
        }

/* ========================================
   THUMBNAILS
   ======================================== */

.thumbnail {
    margin-bottom: var(--spacing-3);
    cursor: pointer;
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: all var(--transition-fast);
    border: 2px solid transparent;
    background-color: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

    .thumbnail:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-md);
        border-color: var(--primary-color);
    }

    .thumbnail:active {
        transform: translateY(0);
    }

.thumbnail-canvas {
    width: 100%;
    height: auto;
    display: block;
}

.thumbnail-label {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    text-align: center;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-light);
}

/* ========================================
   PDF VIEWER
   ======================================== */

.pdf-viewer {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
    overflow: auto;
    padding: var(--spacing-6);
    position: relative;
}

.pdf-canvas {
    max-width: 100%;
    max-height: 100%;
    box-shadow: var(--shadow-xl);
    border-radius: var(--radius-md);
    background-color: white;
    border: 1px solid var(--border-light);
}

/* ========================================
   LOADING STATES
   ======================================== */

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
    backdrop-filter: blur(4px);
}

.spinner-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-4);
    background-color: var(--bg-elevated);
    padding: var(--spacing-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border-light);
    border-top: 4px solid var(--primary-color);
    border-radius: var(--radius-full);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.loading-text {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
}

.loading-progress {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 300px;
    background-color: var(--bg-elevated);
    border-radius: var(--radius-lg);
    padding: var(--spacing-6);
    box-shadow: var(--shadow-xl);
    z-index: var(--z-modal);
}

.progress-bar {
    width: 0%;
    height: 4px;
    background-color: var(--primary-color);
    border-radius: var(--radius-full);
    transition: width var(--transition-base);
    margin-bottom: var(--spacing-3);
}

.progress-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    text-align: center;
    display: block;
}

/* ========================================
   ALERTS AND NOTIFICATIONS
   ======================================== */

.alert-container {
    position: fixed;
    top: calc(var(--header-height) + var(--controls-height) + var(--spacing-4));
    right: var(--spacing-6);
    z-index: var(--z-tooltip);
    max-width: 400px;
}

.alert {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    padding: var(--spacing-4);
    margin-bottom: var(--spacing-3);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }

    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.alert-success {
    background-color: #f0fdf4;
    color: #15803d;
    border: 1px solid #bbf7d0;
}

.alert-error {
    background-color: #fef2f2;
    color: #dc2626;
    border: 1px solid #fecaca;
}

.alert-info {
    background-color: #f0f9ff;
    color: #0369a1;
    border: 1px solid #bae6fd;
}

.alert-warning {
    background-color: #fffbeb;
    color: #d97706;
    border: 1px solid #fed7aa;
}

.alert .close {
    margin-left: auto;
    background: none;
    border: none;
    font-size: var(--font-size-lg);
    cursor: pointer;
    color: inherit;
    opacity: 0.7;
    transition: var(--transition-fast);
}

    .alert .close:hover {
        opacity: 1;
    }

/* ========================================
   MODAL STYLES
   ======================================== */

.modal-content {
    border: none;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
}

.modal-header {
    border-bottom: 1px solid var(--border-light);
    padding: var(--spacing-6);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.modal-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    margin: 0;
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-6);
    max-height: 70vh;
    overflow-y: auto;
}

.modal-footer {
    border-top: 1px solid var(--border-light);
    padding: var(--spacing-6);
    background-color: var(--bg-secondary);
    border-radius: 0 0 var(--radius-xl) var(--radius-xl);
}

/* Document info in modal */
.document-info-section {
    margin-bottom: var(--spacing-6);
    padding: var(--spacing-4);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
}

.document-header {
    margin-bottom: var(--spacing-4);
}

.document-main-title {
    margin: 0;
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
}

.title-link {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition-fast);
}

    .title-link:hover {
        color: var(--primary-900);
        text-decoration: underline;
    }

.document-details-grid {
    margin-top: var(--spacing-4);
}

.detail-group {
    height: 100%;
}

.detail-item {
    margin-bottom: var(--spacing-2);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
}

.detail-label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--text-secondary);
}

.detail-value {
    font-size: var(--font-size-sm);
    color: var(--text-primary);
}

.theme-badges {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-1);
}

.theme-badge {
    display: inline-block;
    padding: var(--spacing-1) var(--spacing-2);
    background-color: var(--primary-color);
    color: var(--text-inverse);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
}

/* Chapters section */
.chapters-section {
    margin-top: var(--spacing-6);
}

.section-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    margin: 0 0 var(--spacing-4) 0;
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
}

.chapters-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.chapter-item {
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-4);
    transition: all var(--transition-fast);
}

    .chapter-item:hover {
        box-shadow: var(--shadow-md);
        border-color: var(--primary-color);
    }

    .chapter-item.active {
        border-color: var(--primary-color);
        background-color: rgba(37, 99, 235, 0.05);
    }

.chapter-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-4);
}

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

.chapter-link {
    text-decoration: none;
    color: inherit;
}

.chapter-title {
    margin: 0 0 var(--spacing-1) 0;
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
}

.chapter-pages {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: var(--spacing-1);
}

.chapter-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-12);
    color: var(--text-muted);
    text-align: center;
}

.empty-message {
    margin-top: var(--spacing-4);
    font-size: var(--font-size-base);
}

/* ========================================
   FORM ELEMENTS
   ======================================== */

.form-group {
    margin-bottom: var(--spacing-4);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-2);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
}

.form-control {
    width: 100%;
    padding: var(--spacing-3);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-base);
    font-size: var(--font-size-sm);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition-fast);
}

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

.form-text {
    margin-top: var(--spacing-1);
    font-size: var(--font-size-xs);
    color: var(--text-muted);
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */

@media (max-width: 1024px) {
    .header-content {
        padding: 0 var(--spacing-4);
    }

    .controls {
        padding: var(--spacing-3) var(--spacing-4);
    }

    .sidebar {
        width: var(--sidebar-width-mobile);
    }

    .search-input-container {
        min-width: 280px;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 60px;
        --controls-height: auto;
    }

    .header {
        padding: 0 var(--spacing-3);
        height: var(--header-height);
    }

    .document-title {
        font-size: var(--font-size-lg);
    }

    .controls {
        flex-wrap: wrap;
        padding: var(--spacing-2) var(--spacing-3);
        gap: var(--spacing-2);
        min-height: var(--controls-height);
    }

    .controls-group {
        gap: var(--spacing-2);
    }

    .controls-center {
        order: -1;
        width: 100%;
        justify-content: center;
        margin-bottom: var(--spacing-2);
    }

    .page-controls {
        width: 100%;
        justify-content: center;
    }

    .sidebar {
        position: absolute;
        top: 0;
        left: 0;
        height: 100%;
        width: var(--sidebar-width-mobile);
        z-index: var(--z-dropdown);
        box-shadow: var(--shadow-xl);
        transform: translateX(-100%);
        transition: transform var(--transition-base);
    }

        .sidebar:not(.hidden) {
            transform: translateX(0);
        }

    .sidebar-close {
        display: flex;
    }

    .pdf-viewer {
        padding: var(--spacing-4);
    }

    .search-input-container {
        left: -50px;
        min-width: 260px;
    }

    .btn-modern {
        padding: var(--spacing-2) var(--spacing-3);
        font-size: var(--font-size-xs);
    }

        .btn-modern i {
            margin-right: var(--spacing-1);
        }

    .alert-container {
        right: var(--spacing-3);
        left: var(--spacing-3);
        max-width: none;
    }

    .document-details-grid .col-md-4 {
        margin-bottom: var(--spacing-3);
    }
}

@media (max-width: 640px) {
    .header-content {
        gap: var(--spacing-2);
    }

    .logo-link img {
        width: 40px;
        height: 40px;
    }

    .document-title {
        font-size: var(--font-size-base);
    }

        .document-title span {
            display: none;
        }

    .controls {
        padding: var(--spacing-2);
    }

    .page-input {
        width: 50px;
    }

    .search-input-container {
        left: -80px;
        min-width: 240px;
    }

    .search-input {
        font-size: var(--font-size-xs);
    }

    .pdf-viewer {
        padding: var(--spacing-2);
    }

    .btn-modern {
        padding: var(--spacing-1) var(--spacing-2);
    }

        .btn-modern span {
            display: none;
        }

    .zoom-controls {
        gap: var(--spacing-1);
    }

    .zoom-level {
        min-width: 40px;
        font-size: var(--font-size-xs);
    }
}

@media (max-width: 480px) {
    .header {
        padding: 0 var(--spacing-2);
    }

    .header-actions .btn-modern span {
        display: none;
    }

    .controls-left,
    .controls-right {
        flex: none;
    }

    .sidebar {
        width: 100vw;
        max-width: 280px;
    }

    .search-input-container {
        position: fixed;
        top: calc(var(--header-height) + var(--spacing-2));
        left: var(--spacing-2);
        right: var(--spacing-2);
        width: auto;
        min-width: 0;
    }

    .modal-dialog {
        margin: var(--spacing-2);
    }

    .modal-header,
    .modal-body,
    .modal-footer {
        padding: var(--spacing-4);
    }
}

/* ========================================
   ACCESSIBILITY ENHANCEMENTS
   ======================================== */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--primary-color);
    color: var(--text-inverse);
    padding: var(--spacing-2) var(--spacing-4);
    text-decoration: none;
    z-index: var(--z-tooltip);
    transition: top var(--transition-fast);
    border-radius: var(--radius-base);
    font-weight: var(--font-weight-medium);
}

    .skip-link:focus {
        top: 6px;
        color: var(--text-inverse);
        text-decoration: none;
    }

/* Focus management */
*:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border-light: #000000;
        --border-base: #000000;
        --text-muted: #000000;
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .spinner {
        animation: none;
    }
}

/* Print styles */
@media print {
    .header,
    .controls,
    .sidebar,
    .alert-container,
    .loading-overlay {
        display: none !important;
    }

    .main-content {
        height: auto;
        overflow: visible;
    }

    .pdf-viewer {
        padding: 0;
        overflow: visible;
    }

    .pdf-canvas {
        box-shadow: none;
        border: none;
        max-width: 100%;
        max-height: none;
    }
}

/* Search result highlight overlay */
.highlight {
	position: absolute;
	background-color: rgba(255, 215, 0, 0.7);
	pointer-events: none;
	z-index: var(--z-tooltip);
	box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
	transition: all 0.2s ease-in-out;
	min-width: 8px;
	min-height: 12px;
}