/* PDF Viewer Styles */
:root {
    --pdf-primary: #4a90e2;
    --pdf-secondary: #357abd;
    --pdf-background: #f8fafc;
    --pdf-sidebar: #ffffff;
    --pdf-border: #e2e8f0;
    --pdf-text: #2d3748;
    --pdf-text-light: #718096;
    --pdf-highlight: #fef08a;
    --pdf-underline: #60a5fa;
    --pdf-strikethrough: #f87171;
    --pdf-pen: #8b5cf6;
    --pdf-note: #fbbf24;
}

/* Dark mode variables */
body.dark-mode {
    --pdf-background: #1a202c;
    --pdf-sidebar: #2d3748;
    --pdf-border: #4a5568;
    --pdf-text: #e2e8f0;
    --pdf-text-light: #a0aec0;
}

/* PDF Header */
.pdf-header {
    background: var(--pdf-sidebar);
    border: 1px solid var(--pdf-border);
    border-radius: 12px;
    margin-bottom: 1rem;
    padding: 1rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.pdf-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: center;
    justify-content: space-between;
}

.file-controls {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.upload-btn, .control-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--pdf-primary);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s ease;
    text-decoration: none;
}

.upload-btn:hover, .control-btn:hover {
    background: var(--pdf-secondary);
    transform: translateY(-1px);
}

/* Annotation Toolbar */
.annotation-toolbar {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    flex-wrap: wrap;
    padding: 0.5rem;
    background: var(--pdf-background);
    border-radius: 8px;
    border: 1px solid var(--pdf-border);
}

.tool-btn, .action-btn {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    padding: 0.5rem;
    background: transparent;
    border: 1px solid var(--pdf-border);
    border-radius: 6px;
    cursor: pointer;
    color: var(--pdf-text);
    font-size: 0.85rem;
    transition: all 0.2s ease;
}

.tool-btn:hover, .action-btn:hover {
    background: var(--pdf-primary);
    color: white;
}

.tool-btn.active {
    background: var(--pdf-primary);
    color: white;
    border-color: var(--pdf-primary);
}

.action-btn.danger {
    border-color: #f87171;
    color: #f87171;
}

.action-btn.danger:hover {
    background: #f87171;
    color: white;
}

.color-picker input[type="color"] {
    width: 30px;
    height: 30px;
    border: 1px solid var(--pdf-border);
    border-radius: 4px;
    cursor: pointer;
}

/* Page Controls */
.page-controls {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.nav-btn, .zoom-btn {
    padding: 0.5rem;
    background: var(--pdf-primary);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.nav-btn:hover, .zoom-btn:hover {
    background: var(--pdf-secondary);
}

.page-info {
    padding: 0.5rem;
    font-weight: 500;
    color: var(--pdf-text);
}

.zoom-controls {
    display: flex;
    gap: 0.3rem;
    align-items: center;
}

#zoom-level {
    min-width: 45px;
    text-align: center;
    font-size: 0.9rem;
    color: var(--pdf-text);
}

/* PDF Viewer Container */
.pdf-viewer-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 1rem;
    height: calc(100vh - 300px);
    min-height: 600px;
}

/* Sidebar */
.pdf-sidebar {
    background: var(--pdf-sidebar);
    border: 1px solid var(--pdf-border);
    border-radius: 12px;
    padding: 1rem;
    overflow-y: auto;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.pdf-sidebar h3 {
    margin: 0 0 1rem 0;
    color: var(--pdf-text);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
}

.annotations-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.no-annotations {
    color: var(--pdf-text-light);
    font-style: italic;
    text-align: center;
    margin: 2rem 0;
}

.annotation-item {
    background: var(--pdf-background);
    border: 1px solid var(--pdf-border);
    border-radius: 8px;
    padding: 0;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.annotation-item:hover {
    border-color: var(--pdf-primary);
    transform: translateY(-1px);
}

.annotation-main {
    flex: 1;
    padding: 0.75rem;
    cursor: pointer;
}

.annotation-actions {
    padding: 0.5rem;
    border-left: 1px solid var(--pdf-border);
    background: rgba(var(--pdf-primary-rgb, 74, 144, 226), 0.05);
    display: flex;
    gap: 0.25rem;
}

.annotation-edit-btn, .annotation-delete-btn {
    border: none;
    border-radius: 4px;
    padding: 0.4rem;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
}

.annotation-edit-btn {
    background: #3b82f6;
    color: white;
}

.annotation-edit-btn:hover {
    background: #2563eb;
    transform: scale(1.1);
}

.annotation-delete-btn {
    background: #ef4444;
    color: white;
}

.annotation-delete-btn:hover {
    background: #dc2626;
    transform: scale(1.1);
}

.annotation-edit-btn:active, .annotation-delete-btn:active {
    transform: scale(0.95);
}

.annotation-type {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--pdf-primary);
    margin-bottom: 0.3rem;
}

.annotation-content {
    font-size: 0.9rem;
    color: var(--pdf-text);
    margin-bottom: 0.3rem;
}

.annotation-page {
    font-size: 0.8rem;
    color: var(--pdf-text-light);
}

/* PDF Main Area */
.pdf-main {
    background: var(--pdf-sidebar);
    border: 1px solid var(--pdf-border);
    border-radius: 12px;
    overflow: hidden;
    position: relative;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.pdf-canvas-container {
    position: relative;
    overflow: auto;
    height: 600px; /* Set a fixed height */
    background: #f0f0f0;
    display: none; /* Hidden by default until PDF is loaded */
    padding: 1rem;
}

.pdf-canvas-container.show {
    display: block;
}

.canvas-wrapper {
    position: relative;
    display: inline-block;
    margin: 0 auto;
    text-align: center;
}

#pdf-canvas {
    display: block;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    background: white;
    border: 1px solid #ddd;
    max-width: 100%;
    height: auto;
}

#annotation-canvas {
    position: absolute;
    top: 0;
    left: 0;
    pointer-events: auto; /* Enable pointer events for annotations */
    z-index: 10;
    background: transparent;
}

#notes-container {
    position: absolute;
    top: 0;
    left: 0;
    transform: translateX(-50%);
    pointer-events: auto; /* Enable pointer events for notes */
    z-index: 20;
}

.sticky-note {
    position: absolute;
    background: var(--pdf-note);
    border: 1px solid #d97706;
    border-radius: 4px;
    padding: 0.5rem;
    min-width: 150px;
    max-width: 250px;
    font-size: 0.8rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    pointer-events: all;
    cursor: pointer;
    z-index: 10;
}

.sticky-note::before {
    content: '';
    position: absolute;
    top: -5px;
    left: 10px;
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-bottom: 5px solid var(--pdf-note);
}

.note-content {
    margin-bottom: 0.3rem;
    color: #92400e;
}

.note-actions {
    display: flex;
    gap: 0.3rem;
    margin-top: 0.3rem;
}

.note-btn {
    padding: 0.2rem 0.4rem;
    border: none;
    border-radius: 3px;
    cursor: pointer;
    font-size: 0.7rem;
    background: rgba(0, 0, 0, 0.1);
    color: #92400e;
}

.note-btn:hover {
    background: rgba(0, 0, 0, 0.2);
}

/* PDF Placeholder */
.pdf-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    background: var(--pdf-background);
}

.placeholder-content {
    text-align: center;
    color: var(--pdf-text-light);
}

.placeholder-content i {
    font-size: 4rem;
    margin-bottom: 1rem;
    color: var(--pdf-primary);
}

.placeholder-content h3 {
    margin-bottom: 0.5rem;
    color: var(--pdf-text);
}

/* Updated Upload Main Button with better styling */
.upload-main-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    margin-top: 1.5rem;
    padding: 1.2rem 2.5rem;
    background: var(--pdf-primary);
    color: white;
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    text-decoration: none;
    border: none;
    box-shadow: 0 4px 12px rgba(74, 144, 226, 0.3);
    position: relative;
    overflow: hidden;
    min-width: 240px;
    min-height: 56px;
    text-align: center;
}

.upload-main-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    transition: all 0.3s ease;
}

.upload-main-btn:hover {
    background: var(--pdf-secondary);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(74, 144, 226, 0.4);
    gap: 0.75rem;
}

.upload-main-btn:hover::before {
    width: 300px;
    height: 300px;
}

.upload-main-btn:active {
    transform: translateY(0);
    box-shadow: 0 4px 12px rgba(74, 144, 226, 0.3);
}

/* Upload icon styling with enhanced size and contrast */
.upload-main-btn i {
    font-size: 1.5rem;
    transition: all 0.3s ease;
    opacity: 0;
    position: absolute;
    left: 1.8rem;
    top: 50%;
    transform: translate(-20px, -50%) scale(0.8);
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
    color: rgba(255, 255, 255, 0.95);
    z-index: 1;
}

.upload-main-btn:hover i {
    opacity: 1;
    transform: translate(0, -50%) scale(1);
    color: white;
    filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.4));
}

/* Text positioning */
.upload-main-btn .btn-text {
    transition: transform 0.3s ease;
    position: relative;
    z-index: 3;
    width: 100%;
    text-align: center;
    display: block;
}

.upload-main-btn:hover .btn-text {
    transform: translateX(15px);
}

/* Additional enhancement for the main upload button */
.upload-main-btn::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transform: translateX(-100%);
    transition: transform 0.6s ease;
}

.upload-main-btn:hover::after {
    transform: translateX(100%);
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background: var(--pdf-sidebar);
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--pdf-border);
}

.modal-header h3 {
    margin: 0;
    color: var(--pdf-text);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--pdf-text-light);
    padding: 0.25rem;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.close-modal:hover {
    background: var(--pdf-background);
    color: var(--pdf-text);
}

.modal-body {
    padding: 1.5rem;
}

.modal-body textarea {
    width: 100%;
    border: 1px solid var(--pdf-border);
    border-radius: 8px;
    padding: 0.75rem;
    font-family: inherit;
    resize: vertical;
    background: var(--pdf-background);
    color: var(--pdf-text);
}

.modal-footer {
    display: flex;
    gap: 0.5rem;
    justify-content: flex-end;
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--pdf-border);
}

.btn-primary, .btn-secondary {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--pdf-primary);
    color: white;
}

.btn-primary:hover {
    background: var(--pdf-secondary);
}

.btn-secondary {
    background: var(--pdf-background);
    color: var(--pdf-text);
    border: 1px solid var(--pdf-border);
}

.btn-secondary:hover {
    background: var(--pdf-border);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .pdf-viewer-container {
        grid-template-columns: 250px 1fr;
    }
    
    .pdf-controls {
        flex-direction: column;
        gap: 0.5rem;
        align-items: stretch;
    }
    
    .annotation-toolbar {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .pdf-viewer-container {
        grid-template-columns: 1fr;
        grid-template-rows: auto 1fr;
    }
    
    .pdf-sidebar {
        max-height: 200px;
    }
    
    .pdf-controls {
        gap: 0.5rem;
    }
    
    .annotation-toolbar {
        flex-wrap: wrap;
        gap: 0.3rem;
    }
    
    .tool-btn, .action-btn {
        padding: 0.4rem;
        font-size: 0.8rem;
    }
    
    .page-controls {
        flex-wrap: wrap;
        gap: 0.3rem;
    }
    
    .upload-main-btn {
        padding: 1rem 2rem;
        font-size: 0.9rem;
        min-height: 48px;
    }
}

@media (max-width: 480px) {
    .pdf-header {
        padding: 0.75rem;
    }
    
    .pdf-controls {
        gap: 0.25rem;
    }
    
    .annotation-toolbar {
        padding: 0.25rem;
    }
    
    .tool-btn span {
        display: none;
    }
    
    .upload-btn, .control-btn {
        padding: 0.4rem 0.8rem;
        font-size: 0.8rem;
    }
    
    .modal-content {
        margin: 1rem;
        width: calc(100% - 2rem);
    }
    
    .upload-main-btn {
        padding: 0.9rem 1.8rem;
        font-size: 0.85rem;
        min-height: 44px;
    }
}

/* Animation classes */
.fade-in {
    animation: fadeIn 0.3s ease-in-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Highlight colors */
.highlight-yellow { background-color: #fef08a; }
.highlight-green { background-color: #bbf7d0; }
.highlight-blue { background-color: #bfdbfe; }
.highlight-pink { background-color: #fce7f3; }
.highlight-orange { background-color: #fed7aa; }

/* Dark mode specific adjustments */
body.dark-mode .pdf-canvas-container {
    background: #2d3748;
}

body.dark-mode #pdf-canvas {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

body.dark-mode .sticky-note {
    background: #d69e2e;
    border-color: #b7791f;
}

body.dark-mode .note-content {
    color: #2d3748;
}

body.dark-mode .placeholder-content {
    color: #a0aec0;
}

body.dark-mode .upload-main-btn {
    box-shadow: 0 4px 12px rgba(74, 144, 226, 0.2);
}

body.dark-mode .upload-main-btn:hover {
    box-shadow: 0 8px 20px rgba(74, 144, 226, 0.3);
}