.selected::after {
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    display: block;
    position: absolute;
    width: 16px;
    height: 16px;
    background: url("spritesheet.png") -0px -0px;
	background-size: 42px 42px;
    content: " ";
    image-rendering: pixelated;
}

.blueGem {
    width: 14px;
    height: 14px;
    background: url("spritesheet.png") -16px -0px;
	background-size: 42px 42px;
}

.purpleGem {
    width: 14px;
    height: 14px;
    background: url("spritesheet.png") -0px -16px;
	background-size: 42px 42px;
}

.greenGem {
    width: 10px;
    height: 14px;
    background: url("spritesheet.png") -14px -16px;
	background-size: 42px 42px;
}

.gold {
    width: 12px;
    height: 12px;
    background: url("spritesheet.png") -30px -0px;
	background-size: 42px 42px;
}

.redGem {
    width: 12px;
    height: 12px;
    background: url("spritesheet.png") -30px -12px;
	background-size: 42px 42px;
}

.silver {
    width: 12px;
    height: 12px;
    background: url("spritesheet.png") -0px -30px;
	background-size: 42px 42px;
}

.whiteGem {
    width: 12px;
    height: 12px;
    background: url("spritesheet.png") -12px -30px;
	background-size: 42px 42px;
}