div.flex {
	display: -webkit-flex;
	display: flex;
}
div.flex > div.half {
	width: 50%;
	padding-left: 5%;
	padding-right: 5%;
	-webkit-flex: 1;
	flex: 1;
}
div.flex > div.half > div.figure > img {
	border: 1px black solid;
}

.presentation iframe {
	aspect-ratio: 4 / 3;
	width: 100%;
	height: 100%;
}