@charset "utf-8";

/* CSS reset */

*, *::before, *::after {
	box-sizing: border-box;
}
* {
	margin: 0;
	padding: 0;
}
input, button, textarea, select {
	font: inherit;
}
body {
	line-height: 1.5;
	-webkit-font-smoothing: antialiased;
}
h1, h2, h3, h4, button, input, label {
  	line-height: 1.1;
}
p, h1, h2, h3, h4, h5, h6 {
	overflow-wrap: break-word;
}
img, picture, video, canvas, svg {
	display: block;
	max-width: 100%;
}

/* End CSS reset */

/* ==========================================================================
   Theme: matches courses.lpcordova.phd (flatly/darkly + shared base.scss)
   ========================================================================== */
:root {
	--navbar-bg: #2C3E50;
	--navbar-fg: #FFFFFF;
	--accent: #3D6E74;
	--accent-hover: #335d62;
	--accent-soft: #93bdbf;
	--accent-tint: #E6F0F1;
	--code: #9a4665;
	--text: #404041;
	--muted: #6c757d;
	--bg: #F4F6F8;
	--surface: #FFFFFF;
	--stage: #EEF2F4;
	--border: #DDE3E8;
	--control-bg: #FFFFFF;
	--shadow: 0 1px 2px rgba(16, 24, 40, 0.06), 0 8px 24px rgba(16, 24, 40, 0.06);
	--radius: 14px;
	--radius-sm: 8px;
	color-scheme: light;
}
@media (prefers-color-scheme: dark) {
	:root {
		--navbar-bg: #1B2733;
		--accent: #93bdbf;
		--accent-hover: #a9cdce;
		--accent-soft: #3D6E74;
		--accent-tint: #26393B;
		--code: #cca2b2;
		--text: #E9ECEF;
		--muted: #A7B0B8;
		--bg: #15191D;
		--surface: #1F252B;
		--stage: #171C21;
		--border: #313A42;
		--control-bg: #252C33;
		--shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.25);
		color-scheme: dark;
	}
}

::selection { background: var(--accent-soft); }

html { scroll-behavior: smooth; }

body {
	font-family: 'Open Sans', system-ui, -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
	font-size: 100%;
	color: var(--text);
	background-color: var(--bg);
	min-height: 100vh;
	display: flex;
	flex-direction: column;
}

code, pre { font-family: 'Source Code Pro', ui-monospace, monospace; color: var(--code); }

a { color: var(--accent); text-underline-offset: 3px; }
a:hover { color: var(--accent-hover); }

.wrap {
	width: 100%;
	max-width: 1080px;
	margin: 0 auto;
	padding-left: 20px;
	padding-right: 20px;
}

/* ---------- Header ---------- */
.site-header {
	background: var(--navbar-bg);
	color: var(--navbar-fg);
	position: sticky;
	top: 0;
	z-index: 10;
	box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06), 0 4px 16px rgba(0, 0, 0, 0.12);
}
.header-inner {
	display: flex;
	align-items: center;
	gap: 14px;
	min-height: 60px;
	flex-wrap: wrap;
}
.brand {
	display: inline-flex;
	align-items: center;
	gap: 10px;
	color: var(--navbar-fg);
	text-decoration: none;
	font-weight: 700;
	font-size: 1.15rem;
	letter-spacing: 0.02em;
}
.brand:hover { color: var(--navbar-fg); }
.brand-mark {
	width: 22px;
	height: 22px;
	border-radius: 6px;
	background:
		radial-gradient(circle at 50% 22%, #fff 0 3px, transparent 3.5px),
		radial-gradient(circle at 25% 75%, #fff 0 3px, transparent 3.5px),
		radial-gradient(circle at 75% 75%, #fff 0 3px, transparent 3.5px),
		linear-gradient(135deg, #3D6E74, #93bdbf);
}
.brand-sub {
	font-weight: 300;
	opacity: 0.8;
	font-size: 0.95rem;
	padding-left: 14px;
	border-left: 1px solid rgba(255, 255, 255, 0.25);
}
@media (max-width: 560px) { .brand-sub { display: none; } }

/* ---------- Footer ---------- */
.site-footer {
	margin-top: auto;
	border-top: 1px solid var(--border);
	background: var(--surface);
	color: var(--muted);
	font-size: 0.9rem;
}
.footer-inner {
	display: flex;
	justify-content: space-between;
	align-items: center;
	gap: 12px;
	min-height: 56px;
}
.site-footer a { font-weight: 600; text-decoration: none; }
.site-footer a:hover { text-decoration: underline; }

/* ---------- Workspace card ---------- */
main.wrap { padding-top: 28px; padding-bottom: 40px; }

.workspace {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	box-shadow: var(--shadow);
	padding: 20px;
}

.eyebrow {
	display: block;
	font-size: 0.75rem;
	font-weight: 700;
	letter-spacing: 0.08em;
	text-transform: uppercase;
	color: var(--muted);
	margin-bottom: 8px;
}

#selectorWrapper {
	position: relative;
	margin: 0 0 16px;
	font-size: 1rem;
	font-weight: 400;
}
#selectorWrapper > select {
	appearance: none;
	-webkit-appearance: none;
	width: 100%;
	padding: 12px 44px 12px 14px;
	font-size: 1.05rem;
	font-weight: 600;
	color: var(--text);
	background-color: var(--control-bg);
	border: 1px solid var(--border);
	border-radius: 10px;
	cursor: pointer;
	transition: border-color .15s, box-shadow .15s;
}
#selectorWrapper > select:hover { border-color: var(--accent-soft); }
#selectorWrapper::after {
	content: "";
	position: absolute;
	right: 16px;
	top: 50%;
	width: 9px;
	height: 9px;
	border-right: 2px solid var(--accent);
	border-bottom: 2px solid var(--accent);
	transform: translateY(-70%) rotate(45deg);
	pointer-events: none;
}

/* ---------- Toolbars (built by Toolbar.js) ---------- */
fieldset { border: none; min-width: 0; }

.toolbar {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 8px 6px;
}
.toolbar .break {
	display: inline-block;
	width: 10px;
}
.toolbar > * { flex: 0 0 auto; }
.toolbar .choice { display: inline-flex; align-items: center; gap: 6px; }
.toolbar input[type="checkbox"] + label,
.toolbar input[type="radio"] + label { margin-right: 8px; font-size: 0.92rem; cursor: pointer; }
.toolbar .label { color: var(--muted); font-size: 0.92rem; }

.toolbar select, .toolbar input, .toolbar button {
	height: 36px;
	padding: 0 12px;
	font-size: 0.92rem;
	color: var(--text);
	background-color: var(--control-bg);
	border: 1px solid var(--border);
	border-radius: var(--radius-sm);
	transition: border-color .15s, background-color .15s, color .15s, box-shadow .15s;
}
.toolbar input[type="text"], .toolbar input:not([type]) , .toolbar input[type="number"] {
	width: 7.5em;
}
.toolbar select { padding-right: 8px; cursor: pointer; }

.toolbar button, .toolbar input[type="button"], .toolbar input[type="submit"] {
	cursor: pointer;
	font-weight: 600;
	color: var(--accent);
	background-color: var(--accent-tint);
	border-color: transparent;
}
.toolbar button:hover:not([disabled]),
.toolbar input[type="button"]:hover:not([disabled]),
.toolbar input[type="submit"]:hover:not([disabled]) {
	background-color: var(--accent);
	color: #fff;
}
.toolbar button:active:not([disabled]) { transform: translateY(1px); }

.toolbar input[type="checkbox"],
.toolbar input[type="radio"] {
	width: 18px;
	height: 18px;
	padding: 0;
	accent-color: var(--accent);
	vertical-align: middle;
}

.toolbar select:focus-visible, .toolbar input:focus-visible, .toolbar button:focus-visible,
#selectorWrapper > select:focus-visible {
	outline: none;
	border-color: var(--accent);
	box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent-soft) 55%, transparent);
}

.toolbar[disabled] { color: var(--muted); }
.toolbar *[disabled], .toolbar[disabled] *,
.toolbar input[type="checkbox"][disabled] + label,
.toolbar input[type="radio"][disabled] + label {
	opacity: 0.45;
	cursor: not-allowed;
}

/* Playback bar: icon buttons */
#algorithmSpecificControls:empty { display: none; }
#generalAnimationControls {
	margin-top: 12px;
	padding-top: 10px;
	border-top: 1px solid var(--border);
}
#generalAnimationControls button {
	width: 38px;
	padding: 0;
	font-size: 1rem;
	border-radius: 50%;
}

/* ---------- Canvas stage ---------- */
.stage {
	position: relative;
	margin: 12px 0 0;
	padding: 16px;
	border-radius: 12px;
	background-color: var(--stage);
	background-image: radial-gradient(color-mix(in srgb, var(--muted) 22%, transparent) 1px, transparent 1px);
	background-size: 18px 18px;
	overflow-x: auto;
}
canvas {
	display: block;
	margin: 0 auto;
	max-width: 100%;
	height: auto;
	background-color: #fff;
	border-radius: 10px;
	box-shadow: 0 1px 3px rgba(16, 24, 40, 0.10), 0 4px 12px rgba(16, 24, 40, 0.06);
}
.empty-hint {
	display: none;
	position: absolute;
	inset: 0;
	margin: auto;
	height: fit-content;
	text-align: center;
	color: var(--muted);
	font-weight: 600;
	pointer-events: none;
}
body.no-algo .empty-hint { display: block; }
body.no-algo canvas { opacity: 0; }
body.no-algo #algorithmSpecificControls { display: none; }

/* ---------- About / help page ---------- */
.doc { max-width: 820px; }
.doc .back { margin-bottom: 16px; font-size: 0.95rem; }
.doc .back a { text-decoration: none; font-weight: 600; }
.toc { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.toc a {
	text-decoration: none;
	font-weight: 600;
	font-size: 0.9rem;
	padding: 6px 14px;
	border-radius: 999px;
	background: var(--accent-tint);
}
.toc a:hover { background: var(--accent); color: #fff; }
.card {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	box-shadow: var(--shadow);
	padding: 24px 28px;
	margin-bottom: 20px;
	scroll-margin-top: 80px;
}
.card h2 { font-size: 1.4rem; font-weight: 600; margin-bottom: 12px; }
.card h3 { font-size: 1.02rem; font-weight: 700; margin: 20px 0 6px; }
.card p { line-height: 1.65; }
.card p + p { margin-top: 10px; }
.controls { display: grid; grid-template-columns: max-content 1fr; gap: 12px 20px; margin: 8px 0 4px; }
.controls dt { font-weight: 600; white-space: nowrap; display: flex; align-items: center; gap: 8px; }
.controls dd { line-height: 1.6; }
@media (max-width: 600px) {
	.controls { grid-template-columns: 1fr; gap: 4px; }
	.controls dd { margin-bottom: 10px; }
}
.key {
	display: inline-grid;
	place-items: center;
	width: 30px;
	height: 30px;
	border-radius: 50%;
	background: var(--accent-tint);
	color: var(--accent);
	font-size: 0.9rem;
}
.note {
	margin-top: 18px;
	padding: 12px 16px;
	border-left: 4px solid var(--accent);
	background: var(--accent-tint);
	border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}