body {
	margin: 0 auto;
	height: 99%;
	width: 99%;
	background-color: #ebebeb;
	background-image:url('bg.png');
} 

#main {
    width: 100%;
    height: 100%;
    display: -webkit-box;
    -webkit-box-pack: center;
    -webkit-box-align: center;
    display: -moz-box;
    -moz-box-pack: center;
    -moz-box-align: center;
    display: -ms-box;
    -ms-box-pack: center;
    -ms-box-align: center;
    display: box;
    box-pack: center;
    box-align: center;
}

img {
	cursor: pointer;
    transition: transform 0.15s;
}

img:active {
    transform: scale(0.9);
}