wp-calypso/client/blocks/jitm/style.scss

// Constrain JITMs to match layout column
.layout__content > .upsell-nudge {
	margin-left: auto;
	margin-right: auto;
	max-width: 1040px;
}

// Customization for the /themes page.
.is-section-themes .layout__content > .upsell-nudge {
	max-width: 100%;
	margin: 40px 0 0 0;
}

// Customization for the /stats page.
.is-section-stats .layout__content > .upsell-nudge {
	max-width: 1224px;
	margin: -25px max(calc(50% - 612px), 32px) 20px;

	@media (max-width: 660px) {
		margin: -15px 16px 15px;
	}

	@media (min-width: 659px) and (max-width: 782px) {
		margin: -10px 32px 15px;
	}
}