:root {
    --bg: #ffffff;
    --bg-sidebar: #f8f9fa;
    --bg-code: #f1f3f5;
    --text: #1a1a2e;
    --text-muted: #6c757d;
    --border: #dee2e6;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --code-bg: #1e1e2e;
    --code-text: #cdd6f4;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --sidebar-w: 280px;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    font-size: 15px;
}

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); text-decoration: underline; }

/* Sidebar */
.sidebar {
    position: fixed;
    top: 0; left: 0;
    width: var(--sidebar-w);
    height: 100vh;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border);
    overflow-y: auto;
    padding: 24px 0;
    z-index: 100;
}

.sidebar-header {
    padding: 0 20px 16px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 12px;
}

.sidebar-header h2 {
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
}

.sidebar-header p {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 2px;
}

.sidebar nav ul {
    list-style: none;
    padding: 0;
}

.sidebar nav > ul > li {
    margin-bottom: 4px;
}

.sidebar nav > ul > li > a {
    display: block;
    padding: 6px 20px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.sidebar nav > ul > li > ul {
    list-style: none;
    padding: 0;
}

.sidebar nav > ul > li > ul > li > a {
    display: block;
    padding: 5px 20px 5px 32px;
    font-size: 13.5px;
    color: var(--text);
    transition: background 0.15s, color 0.15s;
}

.sidebar nav > ul > li > ul > li > a:hover,
.sidebar nav > ul > li > ul > li > a.active {
    background: rgba(37, 99, 235, 0.08);
    color: var(--accent);
    text-decoration: none;
}

/* Main content */
.main {
    margin-left: var(--sidebar-w);
    padding: 40px 48px 80px;
    max-width: 860px;
}

.main h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 12px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border);
}

.main h2 {
    font-size: 24px;
    font-weight: 600;
    margin-top: 40px;
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

.main h3 {
    font-size: 18px;
    font-weight: 600;
    margin-top: 28px;
    margin-bottom: 8px;
}

.main h4 {
    font-size: 15px;
    font-weight: 600;
    margin-top: 20px;
    margin-bottom: 6px;
}

.main p { margin-bottom: 12px; }

.main ul, .main ol {
    margin: 0 0 16px 24px;
}

.main li { margin-bottom: 4px; }

/* Inline code */
.main code {
    background: var(--bg-code);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
    font-family: 'SF Mono', 'Fira Code', Consolas, monospace;
}

/* Code blocks */
.main pre {
    background: var(--code-bg);
    color: var(--code-text);
    padding: 16px 20px;
    border-radius: var(--radius);
    overflow-x: auto;
    margin: 0 0 16px;
    font-size: 13px;
    line-height: 1.6;
}

.main pre code {
    background: none !important;
    padding: 0 !important;
    color: var(--code-text);
    font-size: inherit;
}

/* Tables */
.main table {
    width: 100%;
    border-collapse: collapse;
    margin: 0 0 20px;
    font-size: 14px;
}

.main th, .main td {
    padding: 8px 12px;
    border: 1px solid var(--border);
    text-align: left;
}

.main th {
    background: var(--bg-sidebar);
    font-weight: 600;
}

.main tr:nth-child(even) { background: rgba(0,0,0,0.02); }

/* Blockquotes */
.main blockquote {
    border-left: 4px solid var(--accent);
    padding: 12px 16px;
    margin: 0 0 16px;
    background: rgba(37, 99, 235, 0.04);
    border-radius: 0 var(--radius) var(--radius) 0;
}

.main blockquote p:last-child { margin-bottom: 0; }

/* Section (each page content) */
.doc-section { display: none; }
.doc-section.active { display: block; }

/* Mobile */
.menu-toggle {
    display: none;
    position: fixed;
    top: 12px; left: 12px;
    z-index: 200;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 6px;
    padding: 8px 12px;
    font-size: 18px;
    cursor: pointer;
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.25s ease;
    }
    .sidebar.open { transform: translateX(0); }
    .main { margin-left: 0; padding: 60px 20px 60px; }
    .menu-toggle { display: block; }
}