styles.css

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

:root {
	--dark-clr: hsl(0, 0%, 10%);
	--dark-clr-hover: hsl(0, 0%, 30%);
	--border-grey: hsl(0, 0%, 70%);
	--white-clr: hsl(0, 100%, 100%);
	font-size: 18px;
	font-family: 'Open Sans', sans-serif;
}

* {
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}

body {
	display: flex;
	height: 100vh;
	padding: 1em;
	flex-direction: column;
	justify-content: center;
	align-items: center;
	position: relative;
}

#app {
	display: grid;
	height: 100%;
	width: 50em;
	border: 1px solid var(--dark-clr);
	grid-template-columns: repeat(50, 1fr);
}

#turn-count {
	position: absolute;
	top: 0;
	left: 0;
	margin: 0.5em;
	padding: 0.5em 1em;
	border-radius: 0.5em;
	background-color: var(--dark-clr);
	color: var(--white-clr);
}

.cell {
	border: 1px solid var(--border-grey);
}

.alive {
	background-color: var(--dark-clr);
	color: var(--white-clr);
}

.controls {
	margin-top: 1em;
	background-color: var(--dark-clr);
	border-radius: 1em;
	padding: 0 1em;
}

.btn {
	font-family: inherit;
	border: none;
	margin: 0;
	padding: 1em 2em;
}

.btn-primary {
	background: var(--dark-clr);
	color: var(--white-clr);
	transition: 0.2s ease-in-out;
}

.btn-secondary {
	background: var(--white-clr);
	color: var(--dark-clr);
}

.btn-primary:hover,
.btn-primary:focus {
	background: var(--dark-clr-hover);
	color: hsl(0, 50%, 50%);
	cursor: pointer;
}

.info {
	position: absolute;
	display: flex;
	flex-direction: column;
	align-items: center;
	width: 50vw;
	min-height: 50vh;
	background: hsla(0, 0%, 0%, 0.8);
	color: var(--white-clr);
	padding: 2em;
	border-radius: 1em;
}

#info-close {
	margin-top: 1em;
	border-radius: 1em;
}

p {
	margin: 1em;
}

a {
	color: hsl(0, 50%, 50%);
}

.hidden {
	display: none;
}