#btnUp, #btnLeft, #btnRight, #btnDown, #btnRestart {
	width: 48px;
    height: 48px;
    background-repeat: no-repeat;
    background-position-y: center;
    background-position-x: center;
    border: 2px solid #444444;
    border-radius: 10px;
    background-color: black;
    background-size: contain;
    transition: 0.5s;
}

#btnUp {
	background-image: url(http://i.imgur.com/HRKICBv.png);
}

#btnLeft {
	background-image: url(http://i.imgur.com/lMycSsk.png);
    margin-right: 25px;
}

#btnRight {
	background-image: url(http://i.imgur.com/kxzu7Z4.png);
	margin-left: 25px;
}

#btnDown {
	background-image: url(http://i.imgur.com/6cHmsEs.png);
}

#btnRestart {
	background-image: url(http://i.imgur.com/0vBCAn1.png);
	width: 100px;
	margin-bottom: 15px;
}

#btnUp:hover, #btnLeft:hover, #btnRight:hover, #btnDown:hover, #btnRestart:hover {
    border: 3px solid #b5b0b0;
}