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

:root {
    /* Light theme colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --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);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --sidebar-width: 280px;
}

[data-theme="dark"] {
    /* Dark theme colors */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --accent-color: #60a5fa;
    --accent-hover: #3b82f6;
    --success-color: #34d399;
    --warning-color: #fbbf24;
    --error-color: #f87171;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color 0.2s ease, color 0.2s ease;
}

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

/* Header Styles */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

.header-content {
    max-width: 100%;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.app-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.app-logo {
    border-radius: 6px;
    transition: transform 0.2s ease;
}

.app-title:hover .app-logo {
    transform: scale(1.05);
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

[data-theme="dark"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon,
:root:not([data-theme]) .moon-icon {
    display: none;
}

/* Main Content Layout */
.main-content {
    display: flex;
    flex: 1;
    min-height: calc(100vh - 80px);
}

/* Sidebar Styles */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    padding: 1.5rem;
    overflow-y: auto;
}

.file-input-section {
    margin-bottom: 2rem;
}

.file-input-label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    background-color: var(--accent-color);
    color: white;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 500;
    transition: background-color 0.2s ease;
    border: none;
    font-size: 0.875rem;
}

.file-input-label:hover {
    background-color: var(--accent-hover);
}

#fileInput {
    display: none;
}

.section-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1rem;
}

.clear-all-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.file-list {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.file-item {
    padding: 0.75rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    border: 1px solid transparent;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    justify-content: space-between;
}

.file-item:hover {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
}

.file-item.active {
    background-color: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.file-item svg {
    flex-shrink: 0;
    width: 16px;
    height: 16px;
}

.file-name {
    font-size: 0.875rem;
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    flex: 1;
}

.remove-file-btn {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    padding: 0.25rem;
    border-radius: var(--radius-sm);
    opacity: 0;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.file-item:hover .remove-file-btn {
    opacity: 0.7;
}

.remove-file-btn:hover {
    opacity: 1 !important;
    background-color: rgba(255, 255, 255, 0.2);
}

.file-item.active .remove-file-btn:hover {
    background-color: rgba(255, 255, 255, 0.3);
}

.empty-state {
    text-align: center;
    padding: 2rem 1rem;
    color: var(--text-muted);
}

.empty-state svg {
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state p {
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.empty-state small {
    font-size: 0.75rem;
}

/* Content Area */
.content-area {
    flex: 1;
    overflow-y: auto;
    position: relative;
}

/* Welcome Screen */
.welcome-screen {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100%;
    padding: 2rem;
}

.welcome-content {
    text-align: center;
    max-width: 500px;
}

.welcome-icon {
    margin-bottom: 2rem;
    color: var(--accent-color);
}

.welcome-content h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

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

.welcome-features {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
    text-align: left;
}

.feature {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem;
    background-color: var(--bg-tertiary);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
}

.feature svg {
    color: var(--accent-color);
    flex-shrink: 0;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.cta-button:hover {
    background-color: var(--accent-hover);
}

/* Install Button */
.install-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--radius-md);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

/* Markdown Content */
.markdown-content {
    padding: 2rem;
    max-width: none;
}

.markdown-content.hidden {
    display: none;
}

.content-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.current-file-name {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

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

.action-btn {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

/* Markdown Output Styles */
.markdown-output {
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.8;
    font-size: 1rem;
}

.markdown-output h1,
.markdown-output h2,
.markdown-output h3,
.markdown-output h4,
.markdown-output h5,
.markdown-output h6 {
    color: var(--text-primary);
    font-weight: 600;
    margin: 2rem 0 1rem 0;
    line-height: 1.3;
}

.markdown-output h1 {
    font-size: 2.25rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.markdown-output h2 {
    font-size: 1.875rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.25rem;
}

.markdown-output h3 {
    font-size: 1.5rem;
}

.markdown-output h4 {
    font-size: 1.25rem;
}

.markdown-output h5 {
    font-size: 1.125rem;
}

.markdown-output h6 {
    font-size: 1rem;
}

.markdown-output p {
    margin: 1rem 0;
    color: var(--text-primary);
}

.markdown-output a {
    color: var(--accent-color);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: border-color 0.2s ease;
}

.markdown-output a:hover {
    border-bottom-color: var(--accent-color);
}

.markdown-output ul,
.markdown-output ol {
    margin: 1rem 0;
    padding-left: 2rem;
}

.markdown-output li {
    margin: 0.5rem 0;
    color: var(--text-primary);
}

.markdown-output blockquote {
    margin: 1.5rem 0;
    padding: 1rem 1.5rem;
    background-color: var(--bg-tertiary);
    border-left: 4px solid var(--accent-color);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    font-style: italic;
}

.markdown-output blockquote p {
    margin: 0;
    color: var(--text-secondary);
}

.markdown-output code {
    background-color: var(--bg-tertiary);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    font-family: 'Fira Code', 'Monaco', 'Consolas', monospace;
    font-size: 0.875rem;
    color: var(--text-primary);
}

.markdown-output pre {
    background-color: var(--bg-tertiary);
    padding: 1.5rem;
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
}

.markdown-output pre code {
    background: none;
    padding: 0;
    font-size: 0.875rem;
    line-height: 1.5;
}

.markdown-output table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.markdown-output th,
.markdown-output td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.markdown-output th {
    background-color: var(--bg-tertiary);
    font-weight: 600;
    color: var(--text-primary);
}

.markdown-output td {
    color: var(--text-primary);
}

.markdown-output tr:last-child td {
    border-bottom: none;
}

.markdown-output img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-md);
    margin: 1rem 0;
    box-shadow: var(--shadow-md);
}

.markdown-output hr {
    border: none;
    height: 1px;
    background-color: var(--border-color);
    margin: 2rem 0;
}

/* Code Syntax Highlighting */
.markdown-output .hljs {
    background: var(--bg-tertiary) !important;
    color: var(--text-primary) !important;
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-content {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
        padding: 1rem;
    }
    
    .markdown-content {
        padding: 1rem;
    }
    
    .content-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .welcome-content h2 {
        font-size: 1.5rem;
    }
    
    .welcome-features {
        text-align: center;
    }
    
    .feature {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .header-content {
        padding: 0 1rem;
    }
    
    .app-title {
        font-size: 1.25rem;
    }
    
    .markdown-output {
        font-size: 0.9rem;
    }
    
    .markdown-output h1 {
        font-size: 1.75rem;
    }
    
    .markdown-output h2 {
        font-size: 1.5rem;
    }
    
    .markdown-output h3 {
        font-size: 1.25rem;
    }
}

/* Print Styles */
@media print {
    .header,
    .sidebar,
    .content-actions {
        display: none !important;
    }
    
    .content-area {
        margin: 0;
        box-shadow: none;
    }
    
    .markdown-content {
        padding: 0;
        max-width: none;
    }
    
    .markdown-output {
        max-width: none;
        color: black;
    }
    
    .markdown-output a {
        color: black;
        text-decoration: underline;
    }
}

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

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

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

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

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

/* Animation for theme transition */
* {
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}