the-glorious-startpage/css/centeredbox/centered-box.css

.centeredBar {
	
	width: 100%;
	height: auto;
	
	border: none;
	pointer-events: none;
	
	position: absolute;
	left: 50%;
	top: 50%;
	-webkit-transform: translate(-50%, -50%);
	transform: translate(-50%, -50%);
}

#centeredBox {
	opacity: 1;
	z-index: 2;
	transition:
				opacity var(--transition-speed),
				z-index var(--transition-speed);
}

.centeredBar#centeredBox.hiddenBox {
	opacity: 0;
	z-index: 0;
}