:root {
    --ink: #0f172a;
    --panel: #1a2333;
    --panel-border: #2c3a52;
    --paper: #e7ebf2;
    --muted: #93a0b6;
    --accent: #ffbf00;
    --accent-ink: #3a2c00;
}

* { box-sizing: border-box; }

html, body {
    margin: 0;
    background: var(--ink);
    color: var(--paper);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

a { color: var(--accent); }
a:hover { color: #ffd75c; }

.masthead {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.75rem 1.25rem;
    border-bottom: 1px solid var(--panel-border);
}

.masthead-brand {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    text-decoration: none;
    color: var(--paper);
}

.masthead-brand img { width: 28px; height: 28px; border-radius: 6px; }
.masthead-brand span { font-weight: 600; font-size: 0.95rem; }

.masthead a.back {
    color: var(--muted);
    text-decoration: none;
    font-size: 0.85rem;
}

.masthead a.back:hover { color: var(--paper); }

.layout {
    display: flex;
    max-width: 1100px;
    margin: 0 auto;
    align-items: flex-start;
}

nav.toc {
    width: 230px;
    flex-shrink: 0;
    padding: 2rem 1.25rem;
    position: sticky;
    top: 0;
    max-height: 100vh;
    overflow-y: auto;
    overscroll-behavior: contain;
}

nav.toc h2 {
    font-size: 0.7rem;
    letter-spacing: 0.04em;
    color: var(--muted);
    margin: 1.5rem 0 0.5rem;
    font-weight: 600;
}

nav.toc h2:first-child { margin-top: 0; }

nav.toc ol, nav.toc ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

nav.toc li { margin-bottom: 0.35rem; }

nav.toc a {
    display: block;
    color: var(--paper);
    text-decoration: none;
    font-size: 0.875rem;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    border-left: 2px solid transparent;
}

nav.toc a:hover { background: var(--panel); }

nav.toc a.active {
    color: var(--accent);
    border-left-color: var(--accent);
    background: var(--panel);
}

nav.toc .num {
    display: inline-block;
    width: 1.1rem;
    color: var(--muted);
}

.page-toc {
    margin: 0.35rem 0 0.75rem 0.55rem;
    padding-left: 0.6rem;
    border-left: 1px solid var(--panel-border);
}

.page-toc li { margin-bottom: 0.1rem; }

.page-toc a {
    font-size: 0.8rem;
    color: var(--muted);
    padding: 0.15rem 0.4rem;
    border-left: none;
}

.page-toc li.depth-3 a {
    padding-left: 1.1rem;
    font-size: 0.775rem;
}

.page-toc a:hover { color: var(--paper); }

.page-toc a.current {
    color: var(--accent);
    background: none;
}

main {
    flex: 1;
    min-width: 0;
    padding: 2rem 1.5rem 4rem;
}

.content {
    max-width: 68ch;
}

.content h1 {
    font-family: 'Source Serif 4', Georgia, serif;
    font-weight: 700;
    font-size: 2.1rem;
    line-height: 1.15;
    margin: 0 0 1rem;
    color: #ffffff;
}

.content h2 {
    font-family: 'Source Serif 4', Georgia, serif;
    font-weight: 600;
    font-size: 1.35rem;
    margin: 2rem 0 0.75rem;
    color: #ffffff;
    border-top: 1px solid var(--panel-border);
    padding-top: 1.5rem;
}

.content h2:first-of-type { border-top: none; padding-top: 0; }

.content h3 { font-size: 1.05rem; margin: 1.5rem 0 0.5rem; color: #ffffff; }
.content p, .content li { line-height: 1.65; color: var(--paper); }
.content ul, .content ol { padding-left: 1.4rem; }
.content li { margin-bottom: 0.35rem; }

.content img {
    max-width: 100%;
    border-radius: 8px;
    border: 1px solid var(--panel-border);
    margin: 0.5rem 0;
}

.content code {
    background: var(--panel);
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    padding: 0.1rem 0.35rem;
    font-size: 0.85em;
    font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
}

.content pre {
    background: var(--panel);
    border: 1px solid var(--panel-border);
    border-radius: 8px;
    padding: 1rem;
    overflow-x: auto;
}

.content pre code { background: none; border: none; padding: 0; }

.content table { border-collapse: collapse; width: 100%; font-size: 0.9rem; }
.content th, .content td { border: 1px solid var(--panel-border); padding: 0.4rem 0.6rem; text-align: left; }
.content th { color: var(--muted); font-weight: 600; }

.content button.geolocate {
    font: inherit;
    background: var(--panel);
    border: 1px solid var(--panel-border);
    color: var(--paper);
    border-radius: 6px;
    padding: 0.1rem 0.5rem;
}

.content .loading { color: var(--muted); font-style: italic; }

.content .heading-anchor {
    color: inherit;
    text-decoration: none;
}

.content .heading-anchor::before {
    content: '#';
    position: absolute;
    margin-left: -1.1em;
    color: var(--accent);
    opacity: 0;
}

.content h1:hover .heading-anchor::before,
.content h2:hover .heading-anchor::before,
.content h3:hover .heading-anchor::before,
.content h4:hover .heading-anchor::before,
.content .heading-anchor:focus-visible::before {
    opacity: 1;
}

.page-footer {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-top: 3rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--panel-border);
    font-size: 0.85rem;
    color: var(--muted);
}

.page-footer .edit-source {
    display: inline-block;
    padding: 0.3rem 0.7rem;
    border: 1px solid var(--panel-border);
    border-radius: 6px;
    background: var(--panel);
    color: var(--accent);
    text-decoration: none;
}

.page-footer .edit-source:hover {
    border-color: var(--accent);
    color: #ffd75c;
}

@media (prefers-reduced-motion: no-preference) {
    html { scroll-behavior: smooth; }
}

.content h1, .content h2, .content h3, .content h4 { scroll-margin-top: 1rem; }

@media (max-width: 760px) {
    .layout { display: block; }
    nav.toc { width: auto; position: static; max-height: none; padding: 1rem 1.25rem 0; }
    nav.toc > ol, nav.toc > ul { display: flex; flex-wrap: wrap; gap: 0.4rem; }
    nav.toc li { margin: 0; }
    nav.toc li:has(.page-toc) { width: 100%; }
    .page-toc { display: flex; flex-wrap: wrap; gap: 0.25rem; border-left: none; margin-left: 0; padding-left: 0; }
    .page-toc li.depth-3 a { padding-left: 0.4rem; }
    main { padding: 1.5rem 1.25rem 3rem; }
}