web/www/css/web.css

@namespace epub "http://www.idpf.org/2007/ops";

body{
	font-family: Georgia, serif;
	font-size: 18px;
	padding: 0 3em;
	margin: 8em auto 3em;
	max-width: 55ch;
}

body > header{
	position: absolute;
  left: 0;
	right: 0;
	top: 0;
	background: #fff;
	border-bottom: 1px solid #999;
	box-shadow: 0 0 3px #ccc;
}

body > header ul{
	display: flex;
	align-items: center;
	list-style: none;
	margin: 0;
	padding: 0.5em 1em;
}

body > header li{
	margin-left: 1.5em;
}

body > header li:first-child{
	margin-left: 0;
	margin-right: auto;
}

body > header li:first-child > a{
	display: block;
	width: 180px;
	height: 42px;
	background: no-repeat center/100% url(/images/logo-full.svg);
	font-size: 0;
}

@media(max-width: 96ch){
	body > header{
		position: fixed;
	}

	body > header li:first-child > a{
		width: 90px;
		height: 21px;
	}
}

body > nav,
body > section,
body > article{
	min-height: 100vh;
}

body > section[epub|type~="titlepage"],
body > section[epub|type~="halftitlepage"]{
	min-height: auto;
}

section + section,
section + article,
article + section,
article + article{
	box-sizing: border-box;
	margin-top: 12em !important;
	padding: 0;
}

nav[epub|type~="toc"] ol{
	list-style: none;
}

@media(max-width: 65ch){
	body{
		padding: 0 1em;
	}

	section[epub|type~="imprint"] p{
		width: 100%;
	}
}

@media(prefers-color-scheme: dark){
	body,
	body > header{
		background: #222222;
		color: #ffffff;
	}

	/* These three link colors provide WCAG AAA compliance at 16px */
	a:link{
		color: #6bb9f0;
	}

	a:active{
		color: #e6cc22;
	}

	a:visited{
		color: #dda0dd;
	}

	body > header li:first-child > a,
	img[epub|type~="se:image.color-depth.black-on-transparent"]{
		filter: invert(1);
	}
}

@media(pointer: coarse) or (pointer: none){
	nav[epub|type~="toc"] ol li{
		margin-top: 2em;
		margin-bottom: 2em;
	}
}