:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-button: #f0f0f0;
    --color-primary: #000000;
    --color-secondary: #727474;
    --accent: #007AFF;
    --accent-semi: rgba(0, 122, 255, 0.1);
    --border-color: rgba(0, 0, 0, 0.12);
    --font-mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, "Roboto Mono", monospace;
}

[data-theme="dark"] {
    --bg-primary: #181818;
    --bg-secondary: #1d1d1d;
    --bg-button: #2a2a2a;
    --color-primary: #e4e4e4;
    --color-secondary: rgba(255, 255, 255, 0.5);
    --accent: #007AFF;
    --accent-semi: rgba(0, 122, 255, 0.1);
    --border-color: rgba(255, 255, 255, 0.08);
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-primary);
    color: var(--color-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    font-synthesis: none;
    margin: 0;
}

/* ── Header ── */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 56px;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    z-index: 100;
}

.header-logo {
    font-weight: 600;
    color: var(--color-primary);
    text-decoration: none;
    white-space: nowrap;
}

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

.header-nav a {
    color: var(--color-secondary);
    text-decoration: none;
    font-weight: 500;
    padding: 5px 10px;
    border-radius: 8px;
}

.header-nav a:hover {
    color: var(--color-primary);
    background: var(--bg-button);
}

.header-nav a.active {
    color: var(--color-primary);
    background: var(--bg-button);
}

.theme-btn {
    margin-left: auto !important;
    background: var(--bg-button);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 5px 12px;
    color: var(--color-secondary);
    cursor: pointer;
    font-family: inherit;
    white-space: nowrap;
}

.theme-btn:hover {
    color: var(--color-primary);
}

/* ── Layout ── */
.page-layout {
    display: flex;
    padding-top: 56px;
    min-height: 100vh;
}

/* ── Sidebar ── */
.sidebar {
    width: 272px;
    flex-shrink: 0;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    height: calc(100vh - 56px);
    position: sticky;
    top: 56px;
    overflow-y: auto;
    padding: 16px 8px 32px;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.sidebar::-webkit-scrollbar {
    width: 4px;
}

.sidebar::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 2px;
}

.nav-group {
    margin-bottom: 4px;
}

.nav-group-title {
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    color: var(--color-secondary);
    padding: 10px 12px 4px;
}

.nav-link {
    display: block;
    padding: 4px 12px;
    color: var(--color-primary);
    text-decoration: none;
    border-radius: 8px;
    font-weight: 500;
}

.nav-link:hover {
    color: var(--color-primary);
    background: var(--bg-button);
}

.nav-link.active {
    color: var(--accent);
    background: var(--accent-semi);
}

.nav-link.sub {
    padding-left: 22px;
    font-weight: 400;
}

/* ── Anchor scroll offset ── */
[id] {
    scroll-margin-top: 72px;
}

/* ── Main content ── */
.main-content {
    flex: 1;
    max-width: 900px;
    padding: 48px 40px;
    min-width: 0;
}

/* ── Typography ── */
h1, h2, h3, h4 {
    color: var(--color-primary);
    font-weight: 600;
}

h1 {
    margin: 0 0 16px;
}

h2 {
    margin: 48px 0 16px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
}

h3 {
    margin: 32px 0 12px;
}

h4 {
    margin: 24px 0 8px;
}

p {
    color: var(--color-primary);
    margin: 0 0 16px;
}

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

a:hover {
    text-decoration: underline;
}

/* ── Code ── */
code:not(pre > code) {
    font-family: var(--font-mono);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    padding: 1px 5px 2px;
    border-radius: 5px;
    color: var(--color-primary);
}

pre {
    background: var(--bg-secondary) !important;
    border: 1px solid var(--border-color) !important;
    border-radius: 12px !important;
    padding: 18px 20px !important;
    margin: 12px 0 20px !important;
    overflow-x: auto;
}

pre > code {
    font-family: var(--font-mono) !important;
    line-height: 1.6 !important;
}

/* ── Callouts ── */
.callout {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 12px 16px;
    margin: 20px 0;
    color: var(--color-secondary);
}

.callout.info {
    background: var(--accent-semi);
    border-left: 3px solid var(--accent);
    color: var(--color-primary);
}

/* ── Package cards ── */
.pkg-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: 24px 0;
}

.pkg-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 20px;
}

.pkg-card h3 {
    margin: 0 0 8px;
}

.pkg-card p {
    color: var(--color-secondary);
    margin: 0 0 12px;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.tag {
    background: var(--bg-button);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 2px 8px;
    color: var(--color-secondary);
    font-family: var(--font-mono);
}

/* ── Feature list ── */
.feat-list {
    list-style: none;
    padding: 0;
    margin: 0 0 20px;
}

.feat-list li {
    padding: 8px 0 8px 26px;
    position: relative;
    border-bottom: 1px solid var(--border-color);
}

.feat-list li:last-child {
    border-bottom: none;
}

.feat-list li::before {
    content: "—";
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* ── Table ── */
.data-table {
    width: 100%;
    border-collapse: collapse;
    margin: 12px 0 20px;
}

.data-table th {
    text-align: left;
    padding: 9px 12px;
    background: var(--bg-secondary);
    color: var(--color-secondary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    border-bottom: 1px solid var(--border-color);
}

.data-table td {
    padding: 9px 12px;
    border-bottom: 1px solid var(--border-color);
}

.data-table tr:last-child td {
    border-bottom: none;
}

/* ── Links list ── */
.links-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.links-list li {
    border-bottom: 1px solid var(--border-color);
}

.links-list li:last-child {
    border-bottom: none;
}

.links-list a {
    display: block;
    padding: 10px 0;
}

/* ── FAQ ── */
#faq h3 {
    margin-top: 24px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

#faq h3:first-of-type {
    border-top: none;
    padding-top: 0;
}

/* ── Sidebar backdrop ── */
.sidebar-backdrop {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 250;
}

.sidebar-backdrop.open {
    display: block;
}

.menu-btn {
    display: none;
    position: fixed;
    bottom: 24px;
    left: 20px;
    z-index: 200;
    align-items: center;
    gap: 6px;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 12px;
    height: 40px;
    padding: 0 12px;
    font-family: inherit;
    font-weight: 500;
    cursor: pointer;
}

/* ── Mobile ── */
@media (max-width: 992px) {
    .sidebar {
        display: none;
        position: fixed;
        top: 56px;
        left: 0;
        z-index: 300;
        height: calc(100vh - 56px);
        padding-bottom: 128px;
    }

    .sidebar.open {
        display: block;
    }

    .main-content {
        padding: 32px 10px 96px;
    }

    .pkg-cards {
        grid-template-columns: 1fr;
    }

    .menu-btn {
        display: flex;
    }
}