Template:Callout/styles.css

/* container for both callout types */
.cosmo-callout-container {
	/* default paragraph margin */
	margin-top: .5em;
}

/* special class for making notices of the same width */
.cosmo-callout-container.stacked-notice {
	/* set to fixed width */
    width: 30rem;
    /* fit to container to small resoltuions preventing overflow */
    max-width: 100%;
}

/* special class for making notices of the same width → visible callout element */
.cosmo-callout-container.stacked-notice > .cosmo-callout,
.cosmo-callout-container.stacked-notice > .cosmo-callout-compact {
	/* stretch the visible callout element inside the container to fill it */
	width: 100%;
}