.background {
	background-repeat:no-repeat;
	background-position:50% 50%;
	background-position:50% 50%\9 !important;
}


.fullscreen,
.fullscreen .content-a {
	width: 100%;
	height: 100vh;
	overflow: hidden;
}
.fullscreen.overflow,
.fullscreen.overflow .content-a {
	height: auto;
	min-height: 100%;
}

.content-a {
	display: table;
	width: 100%;
}
.content-b {
	display: table-cell;
	position: relative;
	vertical-align: middle;
	text-align: center;
}
.not-fullscreen .content-a, 
.not-fullscreen {
	height: 50vh;
}