js/page/style.css

@import url('https://fonts.googleapis.com/css2?family=Raleway&display=swap');

:root {
	font-family: sans-serif;
	--color-bg: #eef0f2;
	--color-fg: #222;
	--color-ac: hsl(274deg 100% 90%);
	--color-hl: hsl(274deg 100% 70%);

	--line-mid: .14rem;
	--line-thick: .2rem;
	color: var(--color-fg);
}

* {
	box-sizing: border-box;
}

body {
	background: var(--color-bg);

	display: flex;
	flex-flow: column;
	align-items: center;
	padding: 1em 2em;
	color: #333;
	background: var(--color-bg);
}

body>section {
	width: 100%;
	max-width: 60em;
	margin-top: 1em;
}

h1, h2, h3, h4, h5, h6 {
	font-family: 'Raleway', sans-serif;
	font-weight: normal;
}

h2 {
	padding: 0 1em 0 .2em;
	width: max-content;
	border-bottom: .1em solid var(--color-ac);
}

h3::before {
	content: "\2023";
	margin-right: .6ch;
	color: var(--color-ac);
}

em {
	font-style: normal;
	font-weight: bold;
}

hr {
	all: unset;
	width: 100%;
	border-bottom: .2em solid var(--color-ac);
	grid-column: 1 / -1;
	margin: 1em 0;
}

a.fancy {
	--color-primary: var(--color-hl);
	--color-secondary: white;
	--color-shadow: #0004;
	color: var(--color-primary);
	cursor: pointer;
	display: inline-block;
	font-weight: bold;
	padding: .0em .2em;
	position: relative;
	text-decoration: none;
	transition: all .3s;
}
a.fancy::before {
	content: '';
	display: block;
	position: absolute;
	left: 0;
	right: 0;
	bottom: 0;
	height: .1em;
	background: var(--color-primary);
	transition: all .3s;
	z-index: -1;
}

a.fancy:hover {
	color: var(--color-secondary);
	text-shadow: .2em .3em .2em var(--color-shadow);
}

a.fancy:hover::before {
	height: 100%;
	border-radius: .2em;
}

pre>code {
	display: block;
	border-left: dashed var(--line-mid) var(--color-ac);
	padding-left: 1.6em;
}

span[title] {
	cursor: help;
	border-bottom: dotted currentcolor .16em;
}

code-block:not(:defined) {
	font-family: monospace;
	white-space: pre-line;
}

dl, dt, dd { all: unset; }
dt, dd { display: block; }
dl {
	display: flex;
	flex-flow: column;
}
dt {
	font-weight: bold;
	font-style: italic;
}
dl>*+dt { margin-top: .8em; }
dl>dt+* { margin-top: .6em; }
dl>*+* { margin-top: .4em; }

code { font-size: 1.1em; }

dl>code dt, dl>code dd { all: unset;}
dl>code dt::after { content: '\00A0:\00A0';}

dl>code {
	display: grid;
	grid-template-columns: auto 1fr;
}
dl>code>dt~dd { grid-column: 2/2; }

.columns {
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	gap: 1.4em;
}
.columns>* {
	margin: 0;
	flex: 100%;
}

.all-unset { all: unset; }
.full-width { grid-column: 1/-1; }

table-of-contents ul {
	list-style: none;
	padding: 0;
}

table-of-contents ul li::before {
	content: "\2023";
	color: var(--color-hl);
	margin-right: 1ch;
}

a.back {
	--margin: .6em;

	color: var(--color-hl);
	text-decoration: none;
	padding: .2em;
	padding-top: .3em;
	padding-right: .4em;
	position: absolute;
	top: var(--margin);
	left: var(--margin);
	border-radius: .3em;
}

a.back:hover {
	color: white;
	background: var(--color-hl);
}

a.back::before {
	display: inline-block;
	content: '';
	width: 0;
	height: 0;
	border: solid transparent .4em;
	border-color: transparent currentcolor transparent transparent;
	margin-right: .8em;
	transform: scale(2, 1);
}

.ribbon {
	--color: var(--color-hl);
	left: 0;
	top: 0;
	position: fixed;
	transform: rotate(315deg) translate(-5.4em);

	background-color: var(--color);
	border: .16em dashed #ffffff;
	color: #ffffff;
	font-family: sans-serif;
	font-size: .8rem;
	letter-spacing: .1em;
	line-height: 1.4em;
	padding: .2em 5em;
	text-decoration: none;
	white-space: nowrap;

	box-shadow:
		0 0 0 3px var(--color),
		0 0 20px -3px rgba(0, 0, 0, 0.5);
	text-shadow:
		0 0 0 #ffffff,
		0 0 5px rgba(0, 0, 0, 0.3);
}