wp-calypso/client/reader/update-notice/style.scss

// New Posts Notice
// Slides in when there are new posts available
.reader-update-notice {
	position: fixed;
	right: 16px;
	top: calc(var(--masterbar-height) + 16px);
	background: color-mix(in srgb, var(--color-accent) 96%, transparent);
	padding: 8px 18px 8px 34px;
	border-radius: 24px; /* stylelint-disable-line scales/radii */
	color: var(--color-text-inverted);
	z-index: z-index("root", ".reader-update-notice");
	margin: 0;
	box-sizing: border-box;
	opacity: 0;
	transform: translateY(-100px);
	pointer-events: none;
	transition: background 0.15s ease-in-out, transform 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
	font-size: $font-body;

	@media (min-width: 600px) {
		top: calc(var(--masterbar-height) + (24px * 2));
		right: calc(24px* 2);
	}

	@media (min-width: 782px) {
		top: calc(var(--masterbar-height) + 32px);
		right: 32px;
	}

	&:hover {
		background: var(--color-primary);
	}

	&.is-active {
		opacity: 1;
		transform: translateY(0);
		pointer-events: auto;
		cursor: pointer;
	}
}

.reader-update-notice .gridicon {
	fill: var(--studio-white);
	display: inline-block;
	position: absolute;
	left: 10px;
}