:root {
	--bg: #0f1115;
	--bg-elev: #171a21;
	--bg-elev2: #1e222b;
	--border: #2a2f3a;
	--text: #d7dce5;
	--text-dim: #8b94a3;
	--accent: #6ea8fe;
	--accent-dim: #3b5482;
	--warn: #ffb454;
	--danger: #ff6b6b;
	--good: #5ad19a;
	--radius: 8px;
	--sidebar-w: 290px;
	--topbar-h: 52px;
}

* { box-sizing: border-box; }

html, body {
	margin: 0;
	height: 100%;
	background: var(--bg);
	color: var(--text);
	font: 14px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

.topbar {
	height: var(--topbar-h);
	display: flex;
	align-items: center;
	gap: 18px;
	padding: 0 18px;
	background: var(--bg-elev);
	border-bottom: 1px solid var(--border);
	position: sticky;
	top: 0;
	z-index: 10;
}

.brand { display: flex; align-items: baseline; gap: 9px; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand-mark {
	font-weight: 700;
	letter-spacing: 0.5px;
	background: var(--accent);
	color: #0b0d12;
	padding: 2px 7px;
	border-radius: 5px;
	font-size: 13px;
}
.brand-bundle { color: var(--text-dim); font-size: 13px; }

.topnav { display: flex; gap: 4px; margin-left: 6px; }
.topnav a {
	color: var(--text-dim);
	padding: 6px 12px;
	border-radius: 6px;
	font-weight: 500;
}
.topnav a:hover { background: var(--bg-elev2); text-decoration: none; color: var(--text); }
.topnav a.active { background: var(--accent-dim); color: #fff; }

#search {
	margin-left: auto;
	width: 240px;
	background: var(--bg);
	border: 1px solid var(--border);
	color: var(--text);
	padding: 7px 11px;
	border-radius: 6px;
	font-size: 13px;
}
#search:focus { outline: none; border-color: var(--accent); }

.sidebar-toggle {
	display: none;
	margin-left: 8px;
	flex: 0 0 auto;
	background: var(--bg);
	border: 1px solid var(--border);
	color: var(--text);
	border-radius: 6px;
	padding: 6px 11px;
	font-size: 16px;
	line-height: 1;
	cursor: pointer;
}
.sidebar-toggle:hover { border-color: var(--accent); color: var(--text); }

.layout {
	display: flex;
	height: calc(100vh - var(--topbar-h));
}

.sidebar {
	width: var(--sidebar-w);
	flex: 0 0 var(--sidebar-w);
	overflow-y: auto;
	border-right: 1px solid var(--border);
	padding: 12px 8px 40px;
	background: var(--bg-elev);
}

.group { margin-bottom: 6px; }
.group-head {
	display: flex;
	align-items: center;
	gap: 6px;
	width: 100%;
	background: none;
	border: none;
	color: var(--text-dim);
	font: inherit;
	font-weight: 600;
	text-transform: uppercase;
	letter-spacing: 0.4px;
	font-size: 11px;
	padding: 6px 8px;
	cursor: pointer;
	text-align: left;
}
.group-head:hover { color: var(--text); }
.group-head .caret { transition: transform 0.12s ease; font-size: 9px; }
.group.collapsed .caret { transform: rotate(-90deg); }
.group.collapsed .group-items { display: none; }
.group-count { margin-left: auto; color: var(--accent-dim); font-weight: 600; }

.group-items { list-style: none; margin: 0; padding: 0; }
.nav-item {
	display: block;
	padding: 5px 10px 5px 18px;
	border-radius: 6px;
	color: var(--text);
	font-size: 13px;
	white-space: nowrap;
	overflow: hidden;
	text-overflow: ellipsis;
}
.nav-item:hover { background: var(--bg-elev2); text-decoration: none; }
.nav-item.active { background: var(--accent-dim); color: #fff; }
.nav-empty { color: var(--text-dim); padding: 10px 12px; font-size: 12px; }

.main {
	flex: 1 1 auto;
	overflow-y: auto;
	padding: 28px 36px 80px;
}
.content { max-width: 820px; margin: 0 auto; }

.crumb { color: var(--text-dim); font-size: 12px; margin-bottom: 12px; }
.concept-head { border-bottom: 1px solid var(--border); padding-bottom: 14px; margin-bottom: 8px; }
.concept-type {
	display: inline-block;
	background: var(--bg-elev2);
	color: var(--accent);
	border: 1px solid var(--border);
	padding: 2px 9px;
	border-radius: 20px;
	font-size: 11px;
	font-weight: 600;
	text-transform: uppercase;
	letter-spacing: 0.4px;
}
.tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px; }
.tag {
	background: var(--bg-elev2);
	border: 1px solid var(--border);
	color: var(--text-dim);
	padding: 1px 8px;
	border-radius: 5px;
	font-size: 12px;
}

.markdown h1 { font-size: 24px; margin: 18px 0 12px; }
.markdown h2 { font-size: 19px; margin: 26px 0 10px; border-bottom: 1px solid var(--border); padding-bottom: 5px; }
.markdown h3 { font-size: 16px; margin: 20px 0 8px; }
.markdown code {
	background: var(--bg-elev2);
	padding: 1px 5px;
	border-radius: 4px;
	font-size: 12.5px;
	font-family: "SF Mono", Menlo, Consolas, monospace;
}
.markdown pre {
	background: var(--bg-elev2);
	border: 1px solid var(--border);
	padding: 12px 14px;
	border-radius: var(--radius);
	overflow-x: auto;
}
.markdown pre code { background: none; padding: 0; }
.markdown table { border-collapse: collapse; width: 100%; margin: 12px 0; font-size: 13px; }
.markdown th, .markdown td { border: 1px solid var(--border); padding: 6px 10px; text-align: left; }
.markdown th { background: var(--bg-elev2); }
.markdown blockquote { border-left: 3px solid var(--accent-dim); margin: 12px 0; padding: 2px 14px; color: var(--text-dim); }
.markdown a.broken-link { color: var(--danger); cursor: not-allowed; text-decoration: line-through; }
.markdown a.ext-link::after { content: " ↗"; color: var(--text-dim); font-size: 11px; }

.links-panel {
	margin-top: 32px;
	border-top: 1px solid var(--border);
	padding-top: 18px;
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
	gap: 20px;
}
.links-col h4 {
	margin: 0 0 8px;
	font-size: 12px;
	text-transform: uppercase;
	letter-spacing: 0.4px;
	color: var(--text-dim);
}
.links-col ul { list-style: none; margin: 0; padding: 0; }
.links-col li { padding: 2px 0; font-size: 13px; }
.links-col.broken h4 { color: var(--danger); }
.links-col.broken li { color: var(--danger); font-family: "SF Mono", Menlo, monospace; font-size: 12px; }
.muted { color: var(--text-dim); }

.dash-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
	gap: 14px;
	margin: 18px 0 28px;
}
.stat {
	background: var(--bg-elev);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 16px 18px;
}
.stat .num { font-size: 28px; font-weight: 700; }
.stat .label { color: var(--text-dim); font-size: 12px; text-transform: uppercase; letter-spacing: 0.4px; margin-top: 2px; }
.stat.warn .num { color: var(--warn); }
.stat.danger .num { color: var(--danger); }

.panel {
	background: var(--bg-elev);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 16px 18px;
	margin-bottom: 18px;
}
.panel h3 { margin: 0 0 12px; font-size: 14px; }
.bar-row { display: flex; align-items: center; gap: 10px; margin: 5px 0; font-size: 13px; }
.bar-row .name { width: 150px; color: var(--text); }
.bar-row .bar { height: 8px; background: var(--accent); border-radius: 4px; min-width: 2px; }
.bar-row .val { color: var(--text-dim); }
.chip-list { display: flex; flex-wrap: wrap; gap: 7px; }
.chip {
	background: var(--bg-elev2);
	border: 1px solid var(--border);
	border-radius: 6px;
	padding: 4px 10px;
	font-size: 13px;
}
.broken-row { font-family: "SF Mono", Menlo, monospace; font-size: 12px; padding: 3px 0; }
.broken-row .arrow { color: var(--danger); margin: 0 6px; }

#graph-wrap { position: relative; height: calc(100vh - var(--topbar-h) - 40px); margin: -8px 0 0; }
#graph-canvas { width: 100%; height: 100%; display: block; cursor: grab; }
#graph-canvas:active { cursor: grabbing; }
.graph-hint { position: absolute; top: 10px; left: 10px; color: var(--text-dim); font-size: 12px; pointer-events: none; }
.graph-tip {
	position: absolute;
	background: var(--bg-elev2);
	border: 1px solid var(--border);
	border-radius: 6px;
	padding: 5px 9px;
	font-size: 12px;
	pointer-events: none;
	display: none;
	max-width: 280px;
	z-index: 5;
}

.search-result { padding: 10px 12px; border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 8px; background: var(--bg-elev); display: block; color: var(--text); }
.search-result:hover { border-color: var(--accent-dim); text-decoration: none; }
.search-result .title { font-weight: 600; }
.search-result .sub { color: var(--text-dim); font-size: 12px; }
.search-result .desc { color: var(--text-dim); font-size: 13px; margin-top: 3px; }

.empty-state { color: var(--text-dim); padding: 40px 0; text-align: center; }
mark { background: var(--warn); color: #0b0d12; border-radius: 2px; padding: 0 1px; }

@media (max-width: 720px) {
	.topbar { gap: 8px; padding: 0 10px; }
	.brand-bundle { display: none; }
	.topnav { margin-left: 0; gap: 2px; }
	.topnav a { padding: 6px 7px; }
	#search { width: auto; flex: 1 1 40px; min-width: 0; margin-left: auto; }

	.sidebar-toggle { display: inline-flex; align-items: center; }

	.sidebar {
		position: fixed;
		top: var(--topbar-h);
		left: 0;
		right: 0;
		width: 100%;
		flex: none;
		height: calc(100vh - var(--topbar-h));
		z-index: 20;
		border-right: none;
		display: none;
		padding: 12px 14px 60px;
	}
	body.sidebar-open .sidebar { display: block; }

	.main { padding: 20px 16px 60px; }
	#graph-wrap { height: calc(100vh - var(--topbar-h) - 24px); }
}