/* CSS Variables for Theming */
:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #8b5cf6;
    --bg-color: #ffffff;
    --bg-secondary: #f3f4f6;
    --text-color: #111827;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
}

[data-theme="dark"] {
    --primary-color: #818cf8;
    --primary-hover: #6366f1;
    --secondary-color: #a78bfa;
    --bg-color: #1f2937;
    --bg-secondary: #111827;
    --text-color: #f9fafb;
    --text-secondary: #9ca3af;
    --border-color: #374151;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
}

.logo svg {
    color: var(--primary-color);
}

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

/* Navigation Tabs */
.tabs {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 0;
}

.tabs .container {
    display: flex;
    gap: 0.5rem;
}

.tab-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 1.5rem;
    background: none;
    border: none;
    border-bottom: 3px solid transparent;
    color: var(--text-secondary);
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s;
}

.tab-btn:hover {
    color: var(--text-color);
    background-color: var(--bg-color);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

/* Main Content */
.main-content {
    padding: 2rem 0;
    min-height: calc(100vh - 200px);
}

.editor-section {
    display: none;
}

.editor-section.active {
    display: block;
}

/* Upload Area */
.upload-area {
    background-color: var(--bg-secondary);
    border: 2px dashed var(--border-color);
    border-radius: 12px;
    padding: 3rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
}

.upload-area:hover {
    border-color: var(--primary-color);
    background-color: var(--bg-color);
}

.upload-area svg {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-area h3 {
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.upload-area p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.upload-area.dragover {
    border-color: var(--primary-color);
    background-color: var(--primary-color);
    opacity: 0.1;
}

/* Toolbar */
.toolbar {
    background-color: var(--bg-secondary);
    border-radius: 12px;
    padding: 1rem;
    margin: 1.5rem 0;
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: center;
    box-shadow: var(--shadow);
}

.toolbar-group {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    font-size: 0.875rem;
    font-weight: 500;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
    background-color: var(--bg-secondary);
}

.btn-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    padding: 0;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-icon:hover {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.btn-icon svg {
    color: currentColor;
}

.btn-icon:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Canvas Container */
.canvas-container {
    background-color: var(--bg-secondary);
    border-radius: 12px;
    padding: 2rem;
    margin-top: 1.5rem;
    box-shadow: var(--shadow);
    overflow: auto;
}

#imageCanvas {
    max-width: 100%;
    display: block;
    margin: 0 auto;
    box-shadow: var(--shadow-lg);
}

/* PDF Pages */
.pdf-pages {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1.5rem;
    padding: 1rem;
}

.pdf-page {
    background-color: var(--bg-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    cursor: move;
    transition: all 0.3s;
    position: relative;
}

.pdf-page:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

.pdf-page.selected {
    border-color: var(--primary-color);
    background-color: var(--bg-color);
    box-shadow: 0 0 0 3px var(--primary-color);
}

.pdf-page canvas {
    width: 100%;
    height: auto;
    border-radius: 4px;
}

.pdf-page-number {
    text-align: center;
    margin-top: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

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

.modal.active {
    display: flex;
}

.modal-content {
    background-color: var(--bg-color);
    border-radius: 12px;
    padding: 2rem;
    max-width: 500px;
    width: 90%;
    box-shadow: var(--shadow-lg);
}

.modal-content h3 {
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.modal-actions {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
    margin-top: 1.5rem;
}

/* Form Elements */
.input {
    width: 100%;
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-size: 1rem;
    margin-bottom: 1rem;
}

.input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-row {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.form-row label {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    color: var(--text-color);
    cursor: pointer;
}

.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--border-color);
    outline: none;
    -webkit-appearance: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

.slider::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

/* Filter Group */
.filter-group {
    margin-bottom: 1.5rem;
}

.filter-group label {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.filter-buttons {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

/* Options Panel */
.options-panel {
    background-color: var(--bg-secondary);
    border-radius: 12px;
    padding: 1rem;
    margin-top: 1rem;
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
    box-shadow: var(--shadow);
}

.options-panel label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 80px;
    right: 20px;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.toast {
    background-color: var(--bg-color);
    border-left: 4px solid var(--primary-color);
    border-radius: 8px;
    padding: 1rem 1.25rem;
    min-width: 300px;
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    animation: slideIn 0.3s ease-out;
}

.toast.success {
    border-left-color: var(--success);
}

.toast.error {
    border-left-color: var(--error);
}

.toast.warning {
    border-left-color: var(--warning);
}

.toast-message {
    flex: 1;
    color: var(--text-color);
}

.toast-close {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0;
    width: 20px;
    height: 20px;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Loading Indicator */
.loading-indicator {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 3000;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

.loading-indicator.active {
    display: flex;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.loading-indicator p {
    color: white;
    margin-top: 1rem;
    font-size: 1.125rem;
}

/* Theme Toggle */
.theme-icon {
    transition: opacity 0.3s;
}

[data-theme="light"] .sun-icon {
    opacity: 1;
}

[data-theme="light"] .moon-icon {
    opacity: 0;
    position: absolute;
}

[data-theme="dark"] .sun-icon {
    opacity: 0;
    position: absolute;
}

[data-theme="dark"] .moon-icon {
    opacity: 1;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }

    .header .container {
        flex-direction: row;
    }

    .logo {
        font-size: 1.25rem;
    }

    .tabs .container {
        flex-direction: column;
        gap: 0;
    }

    .tab-btn {
        width: 100%;
        justify-content: center;
    }

    .toolbar {
        flex-direction: column;
    }

    .toolbar-group {
        width: 100%;
        justify-content: center;
    }

    .pdf-pages {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 1rem;
    }

    .modal-content {
        width: 95%;
        padding: 1.5rem;
    }

    .form-row {
        flex-direction: column;
    }

    .toast-container {
        right: 10px;
        left: 10px;
    }

    .toast {
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .upload-area {
        padding: 2rem 1rem;
    }

    .upload-area svg {
        width: 48px;
        height: 48px;
    }

    .pdf-pages {
        grid-template-columns: 1fr;
    }

    .toolbar {
        padding: 0.75rem;
    }

    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.8rem;
    }
}

/* Print Styles */
@media print {
    .header,
    .tabs,
    .toolbar,
    .toast-container,
    .loading-indicator {
        display: none !important;
    }

    .canvas-container {
        box-shadow: none;
        padding: 0;
    }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 5px;
}

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

/* Welcome Modal */
.welcome-modal-content {
    max-width: 700px;
    padding: 2.5rem;
}

.welcome-modal-content h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.welcome-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.welcome-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.welcome-feature {
    text-align: center;
    padding: 1.5rem;
    background-color: var(--bg-secondary);
    border-radius: 12px;
    transition: transform 0.2s;
}

.welcome-feature:hover {
    transform: translateY(-2px);
}

.welcome-icon {
    font-size: 3rem;
    margin-bottom: 0.75rem;
}

.welcome-feature h3 {
    font-size: 1.125rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.welcome-feature p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.welcome-quick-start {
    background-color: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 12px;
    margin-bottom: 1.5rem;
}

.welcome-quick-start h3 {
    font-size: 1.125rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.welcome-quick-start ol {
    margin-left: 1.5rem;
    color: var(--text-color);
}

.welcome-quick-start li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.welcome-tips {
    padding: 1rem;
    background-color: var(--bg-secondary);
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.welcome-tips p {
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-color);
}

.welcome-tips p:last-child {
    margin-bottom: 0;
}

.welcome-tips code {
    background-color: var(--bg-color);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85rem;
    color: var(--primary-color);
}

.welcome-tips a {
    color: var(--primary-color);
    text-decoration: none;
}

.welcome-tips a:hover {
    text-decoration: underline;
}

/* Help Button */
.help-button {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background-color: var(--primary-color);
    color: white;
    border: none;
    box-shadow: var(--shadow-lg);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
    z-index: 999;
}

.help-button:hover {
    background-color: var(--primary-hover);
    transform: scale(1.1);
    box-shadow: 0 12px 20px -5px rgba(0, 0, 0, 0.2);
}

.help-button svg {
    color: white;
}

@media (max-width: 768px) {
    .help-button {
        bottom: 1rem;
        right: 1rem;
        width: 48px;
        height: 48px;
    }

    .welcome-modal-content {
        padding: 1.5rem;
    }

    .welcome-modal-content h2 {
        font-size: 1.5rem;
    }

    .welcome-features {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
}