/* Global variables. */
:root {
	/* Set sans-serif & mono fonts */
	--sans-font: -apple-system, BlinkMacSystemFont, "avenir next", avenir, "segoe ui", "helvetica neue", helvetica,
		Cantarell, Ubuntu, roboto, noto, arial, sans-serif;
	--mono-font: Menlo, Consolas, Monaco, "noto mono", "Liberation Mono", "Lucida Console", monospace;

	/* Default (light) theme */
	--bg: #f8f8ff;
	--accent-bg: #d7eeff;
	--text: #16161d;
	--text-light: #585858;
	--border: #898ea4;
	--accent: #0d47a1;
	--code: #d81b60;
	--preformatted: #444;
	--marked: #ffdd33;
	--disabled: #efefef;
}

/* Dark theme */
@media (prefers-color-scheme: dark) {
	:root {
		color-scheme: dark;
		--bg: #16161d;
		--accent-bg: #27272e;
		--text: #f8f8ff;
		--text-light: #fffff0;
		--accent: #faffc7;
		--code: #dc143c;
		--preformatted: #ddd;
		--disabled: #16161d;
	}
	/* Add a bit of transparency so light media isn't so glaring in dark mode */
	img,
	video {
		opacity: 0.8;
	}
}

/* Reset box-sizing */
*,
*::before,
*::after {
	box-sizing: border-box;
}

/* Reset default appearance */
textarea,
select,
input,
progress {
	appearance: none;
	-webkit-appearance: none;
	-moz-appearance: none;
}

html {
	/* Set the font globally */
	font-family: var(--sans-font);
	scroll-behavior: smooth;
}

/* Make the body a nice central block */
body {
	color: var(--text);
	background-color: var(--bg);
	font-size: 1.15rem;
	line-height: 1.5;
	display: grid;
	grid-template-columns: 1fr min(45rem, 90%) 1fr;
	margin: 0;
}
body > * {
	grid-column: 2;
}

/* Make the header bg full width, but the content inline with body */
body > header {
	background-color: var(--accent-bg);
	border-bottom: 1px solid var(--border);
	text-align: center;
	padding: 0 0.5rem 2rem 0.5rem;
	grid-column: 1 / -1;
}

body > header h1 {
	max-width: 1200px;
	margin: 1rem auto;
}

body > header p {
	max-width: 40rem;
	margin: 1rem auto;
}

/* Add a little padding to ensure spacing is correct between content and header > nav */
main {
	padding-top: 1.5rem;
}

body > footer {
	margin-top: 4rem;
	padding: 2rem 1rem 1.5rem 1rem;
	color: var(--text-light);
	font-size: 0.9rem;
	text-align: center;
	border-top: 1px solid var(--border);
}

/* Format headers */
h1 {
	font-size: 3rem;
}

h2 {
	font-size: 2.6rem;
	margin-top: 3rem;
}

h3 {
	font-size: 2rem;
	margin-top: 3rem;
}

h4 {
	font-size: 1.44rem;
}

h5 {
	font-size: 1.15rem;
}

h6 {
	font-size: 0.96rem;
}

/* Prevent long strings from overflowing container */
p,
h1,
h2,
h3,
h4,
h5,
h6 {
	overflow-wrap: break-word;
}

/* Fix line height when title wraps */
h1,
h2,
h3 {
	line-height: 1.1;
}

/* Reduce header size on mobile */
@media only screen and (max-width: 720px) {
	h1 {
		font-size: 2.5rem;
	}

	h2 {
		font-size: 2.1rem;
	}

	h3 {
		font-size: 1.75rem;
	}

	h4 {
		font-size: 1.25rem;
	}
}

/* Format links & buttons */
a,
a:visited {
	color: var(--accent);
}

a:hover {
	text-decoration: none;
}

button,
[role="button"],
input[type="submit"],
input[type="reset"],
input[type="button"],
label[type="button"] {
	border: none;
	border-radius: 5px;
	background-color: var(--accent);
	font-size: 1rem;
	color: var(--bg);
	padding: 0.7rem 0.9rem;
	margin: 0.5rem 0;
}

button[disabled],
[role="button"][aria-disabled="true"],
input[type="submit"][disabled],
input[type="reset"][disabled],
input[type="button"][disabled],
input[type="checkbox"][disabled],
input[type="radio"][disabled],
select[disabled] {
	opacity: 0.5;
	cursor: not-allowed;
}

input:disabled,
textarea:disabled,
select:disabled {
	cursor: not-allowed;
	background-color: var(--disabled);
}

input[type="range"] {
	padding: 0;
}

/* Set the cursor to '?' on an abbreviation and style the abbreviation to show that there is more information underneath */
abbr[title] {
	cursor: help;
	text-decoration-line: underline;
	text-decoration-style: dotted;
}

button:focus,
button:enabled:hover,
[role="button"]:focus,
[role="button"]:not([aria-disabled="true"]):hover,
input[type="submit"]:focus,
input[type="submit"]:enabled:hover,
input[type="reset"]:focus,
input[type="reset"]:enabled:hover,
input[type="button"]:focus,
input[type="button"]:enabled:hover,
label[type="button"]:focus,
label[type="button"]:hover {
	filter: brightness(1.4);
	cursor: pointer;
}

/* Format navigation */
header > nav {
	font-size: 1rem;
	line-height: 2;
	padding: 1rem 0 0 0;
}

/* Use flexbox to allow items to wrap, as needed */
header > nav ul,
header > nav ol {
	align-content: space-around;
	align-items: center;
	display: flex;
	flex-direction: row;
	flex-wrap: wrap;
	justify-content: center;
	list-style-type: none;
	margin: 0;
	padding: 0;
}

/* List items are inline elements, make them behave more like blocks */
header > nav ul li,
header > nav ol li {
	display: inline-block;
}

header > nav a,
header > nav a:visited {
	margin: 0 0.5rem 1rem 0.5rem;
	border: 1px solid var(--border);
	border-radius: 5px;
	color: var(--text);
	display: inline-block;
	padding: 0.1rem 1rem;
	text-decoration: none;
}

header > nav a:hover {
	border-color: var(--accent);
	color: var(--accent);
	cursor: pointer;
}

/* Reduce nav side on mobile */
@media only screen and (max-width: 720px) {
	header > nav a {
		border: none;
		padding: 0;
		text-decoration: underline;
		line-height: 1;
	}
}

/* Consolidate box styling */
aside,
details,
pre,
progress {
	background-color: var(--accent-bg);
	border: 1px solid var(--border);
	border-radius: 5px;
	margin-bottom: 1rem;
}

aside {
	font-size: 1rem;
	width: 30%;
	padding: 0 15px;
	margin-left: 15px;
	float: right;
}

/* Make aside full-width on mobile */
@media only screen and (max-width: 720px) {
	aside {
		width: 100%;
		float: none;
		margin-left: 0;
	}
}

article,
fieldset {
	border: 1px solid var(--border);
	padding: 1rem;
	border-radius: 5px;
	margin-bottom: 1rem;
}

article h2:first-child,
section h2:first-child {
	margin-top: 1rem;
}

section {
	border-top: 1px solid var(--border);
	border-bottom: 1px solid var(--border);
	padding: 2rem 1rem;
	margin: 3rem 0;
}

/* Don't double separators when chaining sections */
section + section,
section:first-child {
	border-top: 0;
	padding-top: 0;
}

section:last-child {
	border-bottom: 0;
	padding-bottom: 0;
}

details {
	padding: 0.7rem 1rem;
}

summary {
	cursor: pointer;
	font-weight: bold;
	padding: 0.7rem 1rem;
	margin: -0.7rem -1rem;
	word-break: break-all;
}

details[open] > summary + * {
	margin-top: 0;
}

details[open] > summary {
	margin-bottom: 0.5rem;
}

details[open] > :last-child {
	margin-bottom: 0;
}

/* Format tables */
table {
	border-collapse: collapse;
	display: block;
	margin: 1.5rem 0;
	overflow: auto;
	width: 100%;
}

td,
th {
	border: 1px solid var(--border);
	text-align: left;
	padding: 0.5rem;
}

th {
	background-color: var(--accent-bg);
	font-weight: bold;
}

tr:nth-child(even) {
	/* Set every other cell slightly darker. Improves readability. */
	background-color: var(--accent-bg);
}

table caption {
	font-weight: bold;
	margin-bottom: 0.5rem;
}

/* Format forms */
textarea,
select,
input {
	font-size: inherit;
	font-family: inherit;
	padding: 0.5rem;
	margin-bottom: 0.5rem;
	color: var(--text);
	background-color: var(--bg);
	border: 1px solid var(--border);
	border-radius: 5px;
	box-shadow: none;
	max-width: 100%;
	display: inline-block;
}
label {
	display: block;
}
textarea:not([cols]) {
	width: 100%;
}

/* Add arrow to drop-down */
select:not([multiple]) {
	background-image: linear-gradient(45deg, transparent 49%, var(--text) 51%),
		linear-gradient(135deg, var(--text) 51%, transparent 49%);
	background-position: calc(100% - 15px), calc(100% - 10px);
	background-size: 5px 5px, 5px 5px;
	background-repeat: no-repeat;
	padding-right: 25px;
}

/* checkbox and radio button style */
input[type="checkbox"],
input[type="radio"] {
	vertical-align: middle;
	position: relative;
	width: min-content;
}

input[type="checkbox"] + label,
input[type="radio"] + label {
	display: inline-block;
}

input[type="radio"] {
	border-radius: 100%;
}

input[type="checkbox"]:checked,
input[type="radio"]:checked {
	background-color: var(--accent);
}

input[type="checkbox"]:checked::after {
	/* Creates a rectangle with colored right and bottom borders which is rotated to look like a check mark */
	content: " ";
	width: 0.18em;
	height: 0.32em;
	border-radius: 0;
	position: absolute;
	top: 0.05em;
	left: 0.17em;
	background-color: transparent;
	border-right: solid var(--bg) 0.08em;
	border-bottom: solid var(--bg) 0.08em;
	font-size: 1.8em;
	transform: rotate(45deg);
}
input[type="radio"]:checked::after {
	/* creates a colored circle for the checked radio button  */
	content: " ";
	width: 0.25em;
	height: 0.25em;
	border-radius: 100%;
	position: absolute;
	top: 0.125em;
	background-color: var(--bg);
	left: 0.125em;
	font-size: 32px;
}

/* Makes input fields wider on smaller screens */
@media only screen and (max-width: 720px) {
	textarea,
	select,
	input {
		width: 100%;
	}
}

/* Set a height for color input */
input[type="color"] {
	height: 2.5rem;
	padding: 0.2rem;
}

/* do not show border around file selector button */
input[type="file"] {
	border: 0;
}

/* Misc body elements */
hr {
	border: none;
	height: 1px;
	background: var(--border);
	margin: 1rem auto;
}

mark {
	padding: 2px 5px;
	border-radius: 4px;
	background-color: var(--marked);
}

img,
video {
	max-width: 100%;
	height: auto;
	border-radius: 5px;
}

figure {
	margin: 0;
	text-align: center;
}

figcaption {
	font-size: 0.9rem;
	color: var(--text-light);
	margin-bottom: 1rem;
}

blockquote {
	margin: 2rem 0 2rem 2rem;
	padding: 0.4rem 0.8rem;
	border-left: 0.35rem solid var(--accent);
	color: var(--text-light);
	font-style: italic;
}

cite {
	font-size: 0.9rem;
	color: var(--text-light);
	font-style: normal;
}

dt {
	color: var(--text-light);
}

/* Use mono font for code elements */
code,
pre,
pre span,
kbd,
samp {
	font-family: var(--mono-font);
	color: var(--code);
}

kbd {
	color: var(--preformatted);
	border: 1px solid var(--preformatted);
	border-bottom: 3px solid var(--preformatted);
	border-radius: 5px;
	padding: 0.1rem 0.4rem;
}

pre {
	padding: 1rem 1.4rem;
	max-width: 100%;
	overflow: auto;
	color: var(--preformatted);
}

/* Fix embedded code within pre */
pre code {
	color: var(--preformatted);
	background: none;
	margin: 0;
	padding: 0;
}

/* Progress bars */
/* Declarations are repeated because you */
/* cannot combine vendor-specific selectors */
progress {
	width: 100%;
}

progress:indeterminate {
	background-color: var(--accent-bg);
}

progress::-webkit-progress-bar {
	border-radius: 5px;
	background-color: var(--accent-bg);
}

progress::-webkit-progress-value {
	border-radius: 5px;
	background-color: var(--accent);
}

progress::-moz-progress-bar {
	border-radius: 5px;
	background-color: var(--accent);
	transition-property: width;
	transition-duration: 0.3s;
}

progress:indeterminate::-moz-progress-bar {
	background-color: var(--accent-bg);
}