nextcloud-breeze-dark/core/css/apps/_notifications.scss

 /* Notifications ----------------------------------------------------------- */

#notification {
	background-color: $background-normal;
	border: 1px solid $decoration-normal;
	border-top: none;

	a {
		color: $foreground-link;
	}
}

.notification-container {
	background-color: $background-normal;
	border-color: $decoration-normal;

	.notification-time {
		opacity: 1;
		color: $foreground-inactive;
	}

	.notification {
		color: $foreground-normal;
	}

	a {
		color: $foreground-link;
	}
}

.notification:not(:last-child) {
	border-bottom: 1px solid $decoration-normal;
}