/* CSS Variables for theming */
:root {
    /* Light theme colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --text-muted: #adb5bd;
    --border-color: #dee2e6;
    --border-hover: #adb5bd;
    --accent-color: #007bff;
    --accent-hover: #0056b3;
    --success-color: #28a745;
    --error-color: #dc3545;
    --warning-color: #ffc107;
    --shadow-light: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.15);
    --shadow-heavy: rgba(0, 0, 0, 0.2);

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;

    /* Border radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    /* Transitions */
    --transition-fast: 0.1s ease;
    --transition-normal: 0.2s ease;
    --transition-slow: 0.3s ease;
}

/* Dark theme colors */
[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #404040;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --text-muted: #808080;
    --border-color: #404040;
    --border-hover: #606060;
    --accent-color: #4dabf7;
    --accent-hover: #74c0fc;
    --success-color: #51cf66;
    --error-color: #ff6b6b;
    --warning-color: #ffd43b;
    --shadow-light: rgba(0, 0, 0, 0.3);
    --shadow-medium: rgba(0, 0, 0, 0.4);
    --shadow-heavy: rgba(0, 0, 0, 0.5);
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition-fast), color var(--transition-fast);
    min-height: 100vh;
}

/* Container */
.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.title .icon {
    font-size: 1.75rem;
}

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

.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
}

.theme-toggle:hover {
    background-color: var(--bg-tertiary);
    border-color: var(--border-hover);
}

.theme-icon {
    font-size: 1.2rem;
}

.github-link {
    color: var(--text-primary);
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    height: 40px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-primary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9rem;
}

.github-link:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
    background-color: var(--bg-tertiary);
}

.github-text {
    white-space: nowrap;
}

/* Main content */
.main {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
    width: 100%;
}

/* Upload section */
.upload-section {
    margin-bottom: var(--spacing-xxl);
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xxl);
    text-align: center;
    transition: all var(--transition-normal);
    background-color: var(--bg-secondary);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

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

.upload-area.dragover {
    border-color: var(--accent-color);
    background-color: var(--bg-tertiary);
    transform: scale(1.02);
}

.upload-content {
    max-width: 400px;
    margin: 0 auto;
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.7;
}

.upload-content h2 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.upload-content p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.supported-formats {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-lg);
}

.upload-btn {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.upload-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--shadow-medium);
}

/* Processing section */
.processing-section {
    text-align: center;
    padding: var(--spacing-xxl) 0;
}

.processing-content h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.processing-content p {
    color: var(--text-secondary);
}

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

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

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

/* Results section */
.results-section {
    margin-bottom: var(--spacing-xxl);
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.results-header h2 {
    font-size: 1.75rem;
    color: var(--text-primary);
}

.result-controls {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    white-space: nowrap;
}

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

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--shadow-medium);
}

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

.btn-secondary:hover {
    background-color: var(--border-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--shadow-medium);
}

.btn-icon {
    font-size: 1.1rem;
}

/* Preview container */
.preview-container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: 0 4px 20px var(--shadow-light);
}

.preview-tabs {
    display: flex;
    background-color: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    background: none;
    border: none;
    color: var(--text-secondary);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    border-bottom: 3px solid transparent;
}

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

.tab-btn.active {
    color: var(--accent-color);
    border-bottom-color: var(--accent-color);
    background-color: var(--bg-secondary);
}

.tab-content {
    position: relative;
    min-height: 400px;
}

.tab-pane {
    display: none;
    padding: var(--spacing-lg);
}

.tab-pane.active {
    display: block;
}

/* SVG and Image containers */
.svg-container,
.image-container {
    display: flex;
    justify-content: flex-start;
    align-items: flex-start;
    min-height: 400px;
    max-height: 600px;
    background-color: var(--bg-primary);
    border-radius: var(--radius-md);
    overflow: auto;
    position: relative;
    padding: var(--spacing-md);
    /* Enhanced scrollbar styling */
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) var(--bg-tertiary);
}

.svg-container::-webkit-scrollbar,
.image-container::-webkit-scrollbar {
    width: 12px;
    height: 12px;
}

.svg-container::-webkit-scrollbar-track,
.image-container::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: 6px;
}

.svg-container::-webkit-scrollbar-thumb,
.image-container::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 6px;
    border: 2px solid var(--bg-tertiary);
}

.svg-container::-webkit-scrollbar-thumb:hover,
.image-container::-webkit-scrollbar-thumb:hover {
    background: var(--border-hover);
}

.svg-container::-webkit-scrollbar-corner,
.image-container::-webkit-scrollbar-corner {
    background: var(--bg-tertiary);
}

.svg-container svg,
.image-container img {
    min-width: auto;
    min-height: auto;
    max-width: none;
    max-height: none;
    width: auto;
    height: auto;
    object-fit: none;
    flex-shrink: 0;
}

/* Centering when content is smaller than container */
.svg-container.centered,
.image-container.centered {
    justify-content: center;
    align-items: center;
}

.svg-container.centered svg,
.image-container.centered img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

/* Code container */
.code-container {
    position: relative;
    background-color: var(--bg-primary);
    border-radius: var(--radius-md);
    overflow: hidden;
}

#svg-code-content {
    background-color: var(--bg-tertiary);
    padding: var(--spacing-lg);
    margin: 0;
    overflow-x: auto;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    color: var(--text-primary);
    max-height: 400px;
    overflow-y: auto;
}

.copy-btn {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.copy-btn:hover {
    background-color: var(--accent-hover);
}

.copy-icon {
    font-size: 1rem;
}

/* Error section */
.error-section {
    text-align: center;
    padding: var(--spacing-xxl) 0;
}

.error-content {
    max-width: 500px;
    margin: 0 auto;
}

.error-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.7;
}

.error-content h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--error-color);
}

.error-content p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
    text-align: center;
    margin-top: auto;
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive design */
@media (max-width: 768px) {
    .header-content {
        padding: 0 var(--spacing-md);
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }

    .title {
        font-size: 1.25rem;
    }

    .header-controls {
        gap: var(--spacing-sm);
    }

    .github-text {
        display: none;
    }

    .github-link {
        padding: var(--spacing-sm);
        width: 40px;
    }

    .main {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .upload-area {
        padding: var(--spacing-xl) var(--spacing-lg);
    }

    .upload-icon {
        font-size: 3rem;
    }

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

    .results-header {
        flex-direction: column;
        align-items: stretch;
    }

    .result-controls {
        justify-content: center;
    }

    .preview-tabs {
        flex-direction: column;
    }

    .tab-btn {
        border-bottom: none;
        border-right: 3px solid transparent;
    }

    .tab-btn.active {
        border-bottom: none;
        border-right-color: var(--accent-color);
    }

    .svg-container,
    .image-container {
        min-height: 300px;
    }
}

@media (max-width: 480px) {
    .upload-area {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .upload-icon {
        font-size: 2.5rem;
    }

    .upload-content h2 {
        font-size: 1.25rem;
    }

    .btn {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.9rem;
    }

    .svg-container,
    .image-container {
        min-height: 250px;
    }
}

/* Utility classes */
.hidden {
    display: none !important;
}

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

/* Focus styles for accessibility */
button:focus,
input:focus,
a:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Smooth scrolling for code container */
#svg-code-content {
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) var(--bg-tertiary);
}

#svg-code-content::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

#svg-code-content::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
}

#svg-code-content::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

#svg-code-content::-webkit-scrollbar-thumb:hover {
    background: var(--border-hover);
}