themes-wordpress/seedlet-blocks/sass/blocks/_links.scss

/**
 * Links in navigation
 */
.wp-block-navigation-link {
	a {
		text-underline-offset: 0.4rem;
		:hover{
			text-decoration: underline;
		}
	}
} 

/**
 * Links in Content
 */
.is-root-container, // Editor class hack.
.wp-block-post-content {
	a {
		text-decoration-thickness: 1px;
		text-underline-offset: 0.2em;
	}
}