Template:ContentGrid/styles.css

.tpl-contentgrid {
	margin: 1em 0;
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
	gap: 2em;
	grid-auto-rows: minmax(100px, auto);
}

.tpl-contentgrid .mw-tpl-colorbox {
	margin: 0; /* in favour of grid-gap on [[Template:ContentGrid]] */
}