style.scss

.wp-block-cover-image,
.wp-block-cover {
	position: relative;
	background-size: cover;
	background-position: center center;
	min-height: 430px;
	width: 100%;
	display: flex;
	justify-content: center;
	align-items: center;
	padding: 1em;
	// This block has customizable padding, border-box makes that more predictable.
	box-sizing: border-box;

	&.has-parallax {
		background-attachment: fixed;

		// Mobile Safari does not support fixed background attachment properly.
		// See also https://stackoverflow.com/questions/24154666/background-size-cover-not-working-on-ios
		// Chrome on Android does not appear to support the attachment at all: https://issuetracker.google.com/issues/36908439
		@supports (-webkit-overflow-scrolling: touch) {
			background-attachment: scroll;
		}

		// Remove the appearance of scrolling based on OS-level animation preferences.
		@media (prefers-reduced-motion: reduce) {
			background-attachment: scroll;
		}
	}

	&.is-repeated {
		background-repeat: repeat;
		background-size: auto;
	}

	/**
	 * Set a default background color for has-background-dim _unless_ it includes another
	 * background-color class (e.g. has-green-background-color). The presence of another
	 * background-color class implies that another style will provide the background color
	 * for the overlay.
	 *
	 * See:
	 *   - Issue with background color specificity: https://github.com/WordPress/gutenberg/issues/26545
	 *   - Issue with alternative fix: https://github.com/WordPress/gutenberg/issues/26545
	 */
	&.has-background-dim:not([class*="-background-color"]) {
		background-color: $black;
	}

	&.has-background-dim::before {
		content: "";
		background-color: inherit;
	}

	&.has-background-dim:not(.has-background-gradient)::before,
	.wp-block-cover__gradient-background {
		position: absolute;
		top: 0;
		left: 0;
		bottom: 0;
		right: 0;
		z-index: z-index(".wp-block-cover.has-background-dim::before");
		opacity: 0.5;
	}

	@for $i from 1 through 10 {
		&.has-background-dim.has-background-dim-#{ $i * 10 } {
			&:not(.has-background-gradient)::before,
			.wp-block-cover__gradient-background {
				opacity: $i * 0.1;
			}
		}
	}

	// Apply max-width to floated items that have no intrinsic width
	&.alignleft,
	&.alignright {
		max-width: $content-width * 0.5;
		width: 100%;
	}

	// Using flexbox without an assigned height property breaks vertical center alignment in IE11.
	// Appending an empty ::after element tricks IE11 into giving the cover image an implicit height, which sidesteps this issue.
	&::after {
		display: block;
		content: "";
		font-size: 0;
		min-height: inherit;

		// IE doesn't support flex so omit that.
		@supports (position: sticky) {
			content: none;
		}
	}

	// Aligned cover blocks should not use our global alignment rules
	&.aligncenter,
	&.alignleft,
	&.alignright {
		display: flex;
	}

	.wp-block-cover__inner-container {
		width: 100%;
		z-index: z-index(".wp-block-cover__inner-container");
		*:not(.has-text-color) {
			color: $white;
		}
	}

	&.is-light {
		.wp-block-cover__inner-container {
			*:not(.has-text-color) {
				color: $black;
			}
		}
	}

	p,
	h1,
	h2,
	h3,
	h4,
	h5,
	h6 {
		&:not(.has-text-color) {
			color: inherit;
		}
	}

	// Position: Top
	&.is-position-top-left {
		align-items: flex-start;
		justify-content: flex-start;
	}
	&.is-position-top-center {
		align-items: flex-start;
		justify-content: center;
	}
	&.is-position-top-right {
		align-items: flex-start;
		justify-content: flex-end;
	}
	// Position: Center
	&.is-position-center-left {
		align-items: center;
		justify-content: flex-start;
	}
	&.is-position-center-center {
		align-items: center;
		justify-content: center;
	}
	&.is-position-center-right {
		align-items: center;
		justify-content: flex-end;
	}
	// Position: Bottom
	&.is-position-bottom-left {
		align-items: flex-end;
		justify-content: flex-start;
	}
	&.is-position-bottom-center {
		align-items: flex-end;
		justify-content: center;
	}
	&.is-position-bottom-right {
		align-items: flex-end;
		justify-content: flex-end;
	}

	&.has-custom-content-position.has-custom-content-position {
		.wp-block-cover__inner-container {
			margin: 0;
			width: auto;
		}
	}

	// Extra specificity for in edit mode where other styles would override it otherwise.
	img.wp-block-cover__image-background,
	video.wp-block-cover__video-background {
		position: absolute;
		top: 0;
		left: 0;
		right: 0;
		bottom: 0;
		margin: 0;
		padding: 0;
		width: 100%;
		height: 100%;
		max-width: none;
		max-height: none;
		object-fit: cover;
		outline: none;
		border: none;
		box-shadow: none;
	}
}

.wp-block-cover__video-background {
	z-index: z-index(".wp-block-cover__video-background");
}

.wp-block-cover__image-background {
	z-index: z-index(".wp-block-cover__image-background");
}

// Styles below only exist to support older versions of the block.
// Versions that not had inner blocks and used an h2 heading had a section (and not a div) with a class wp-block-cover-image (and not a wp-block-cover).
// We are using the previous referred differences to target old versions.

section.wp-block-cover-image h2,
.wp-block-cover-image-text,
.wp-block-cover-text {
	color: $white;
	a,
	a:hover,
	a:focus,
	a:active {
		color: $white;
	}
}

.wp-block-cover-image
.wp-block-cover {
	&.has-left-content {
		justify-content: flex-start;
	}

	&.has-right-content {
		justify-content: flex-end;
	}
}

section.wp-block-cover-image.has-left-content > h2,
.wp-block-cover-image.has-left-content .wp-block-cover-image-text,
.wp-block-cover.has-left-content .wp-block-cover-text {
	margin-left: 0;
	text-align: left;
}

section.wp-block-cover-image.has-right-content > h2,
.wp-block-cover-image.has-right-content .wp-block-cover-image-text,
.wp-block-cover.has-right-content .wp-block-cover-text {
	margin-right: 0;
	text-align: right;
}

section.wp-block-cover-image > h2,
.wp-block-cover-image .wp-block-cover-image-text,
.wp-block-cover .wp-block-cover-text {
	font-size: 2em;
	line-height: 1.25;
	z-index: 1;
	margin-bottom: 0;
	max-width: $content-width;
	padding: 0.44em;
	text-align: center;
}