body {
	background-color: #9dff00;
	color: #000;
	font-family: Futura, sans-serif;
	font-size: 1.5rem;
	padding: 1rem;
	text-align: center;
}

main {
	margin: 0 auto;
	max-width: 800px;
}

a {
	color: #9900ff;
	text-decoration: none;
}

a:hover,
a:focus,
a:active {
	color: #000;
	text-decoration: underline;
}

#board {
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	margin: 0 auto;
	max-width: 600px;
}

.row {
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	width: 600px;
}

.square {
	background-color: #fff;
    color: #9900ff;
	border: 5px solid #000;
	box-sizing: border-box;
	font-size: 8rem;
	font-weight: 100;
	height: 200px;
	line-height: 190px;
	text-align: center;
	width: 200px;
	cursor: pointer;
}

.previewed::after {
    content: attr(data-preview);
    display: block;
    font-size: 8rem;
	font-weight: 100;
    color: #9dff00;
}

#board > div:nth-child(2) > div:nth-child(2) {
	border-color: #000;
}

#board > div:nth-child(2) > div:nth-child(3),
#board > div:nth-child(2) > div:nth-child(1) {
	border-top-color: #000;
	border-bottom-color: #000;
}

#board > div:nth-child(3) > div:nth-child(2) {
	border-top-color: #000;
}

#board > div:nth-child(3) > div:nth-child(2),
#board > div:nth-child(1) > div:nth-child(2) {
	border-left-color: #000;
	border-right-color: #000;
}

.square:hover,
.square:focus,
.square:active {
	background-color: #9900ff;
	color: #9dff00;
    outline: none;
    box-shadow: none;
}

#reset {
	background-color: #fff;
    color: #9900ff;
	border: 5px solid #000;
	box-sizing: border-box;
	cursor: pointer;
	font-size: 1.5rem;
	font-weight: 500;
	height: 50px;
	margin: 0 auto;
	margin: 1rem;
	width: 200px;
}

#reset:hover,
#reset:focus,
#reset:active {
	background-color: #9900ff;
	color: #9dff00;
}

/* media queries */
@media (max-width: 700px) {
	.square {
		height: 150px;
		line-height: 140px;
		width: 150px;
	}
}

@media (max-width: 500px) {
	.square {
		height: 100px;
		line-height: 90px;
		width: 100px;
		font-size: 5rem;
	}
}

@media (max-width: 356px) {
	.square {
		height: 75px;
		line-height: 65px;
		width: 75px;
		font-size: 4rem;
	}
}

@media (max-width: 278px) {
	.square {
		height: 50px;
		line-height: 40px;
		width: 50px;
		font-size: 3rem;
	}
}