:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --background: #ffffff;
    --surface: #f8fafc;
    --text: #1e293b;
    --border: #e2e8f0;
    --radius: 8px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--background);
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border);
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

header p {
    color: var(--secondary-color);
    font-size: 1.125rem;
}

.search-box {
    margin-bottom: 2rem;
}

#searchInput {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    transition: border-color 0.2s;
}

#searchInput:focus {
    outline: none;
    border-color: var(--primary-color);
}

.article-list {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
}

.article-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.article-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.article-card h3 {
    margin-bottom: 0.75rem;
    color: var(--text);
    font-size: 1.25rem;
}

.article-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: var(--secondary-color);
}

.file-type {
    background: var(--primary-color);
    color: white;
    padding: 0.125rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
}

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

.btn {
    padding: 0.5rem 1rem;
    border-radius: 6px;
    text-decoration: none;
    font-size: 0.875rem;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    border: none;
    cursor: pointer;
}

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

.btn-primary:hover {
    background: #1d4ed8;
}

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

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

.back-link {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 1rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.view-options {
    float: right;
    display: flex;
    gap: 0.5rem;
}

.markdown-body {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem;
    background: white;
    border-radius: var(--radius);
}

.loading {
    text-align: center;
    padding: 3rem;
    color: var(--secondary-color);
}

.error {
    text-align: center;
    padding: 3rem;
    color: #dc2626;
    background: #fef2f2;
    border-radius: var(--radius);
}

.dark-theme {
    --background: #0f172a;
    --surface: #1e293b;
    --text: #f1f5f9;
    --border: #334155;
}

.dark-theme .markdown-body {
    background: var(--surface);
    color: var(--text);
}

@media print {
    .back-link,
    .view-options {
        display: none;
    }
    
    .markdown-body {
        padding: 0;
        max-width: 100%;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    .article-list {
        grid-template-columns: 1fr;
    }
    
    header h1 {
        font-size: 2rem;
    }
}

.mermaid {
    text-align: center;
    margin: 2rem 0;
}

pre {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 1rem;
    overflow-x: auto;
    margin: 1rem 0;
}

code {
    background: var(--surface);
    padding: 0.125rem 0.25rem;
    border-radius: 4px;
    font-size: 0.875em;
}