themes-wordpress/blockbase/sass/_style.scss

/*
 * This is a refactored style sheet
 * Currently it is being loaded within ponyfill
 * As ponyfill gets refactored, add the necessary styles here.
 */
 
/*
 * Button hover styles.
 * Necessary until the following issue is resolved in Gutenberg:
 * https://github.com/WordPress/gutenberg/issues/27075
 */

 :is(
	.wp-block-search__button,
	.wp-block-button__link
):is(
	:hover,
	:active,
	:focus
) {
  text-decoration: none;
	cursor: pointer;
  color: var(--wp--custom--button--hover--color--text);
  background-color: var(--wp--custom--button--hover--color--background);
  border-color: var(--wp--custom--button--hover--border--color);
}

:is(
	.wp-block-search__button,
	.wp-block-button__link
):focus {
	outline: 1.5px dotted var(--wp--preset--color--foreground);
	outline-offset: 3px;
}

:is(
  .is-style-outline.wp-block-button,
  .is-style-outline.wp-block-button__link
) {
  color: var(--wp--custom--button--outline--color--text, var(--wp--custom--button--border--color) );
}

:is(
  .is-style-outline>.wp-block-button__link,
  .is-style-outline.wp-block-button__link
):not(.has-background):hover {
  color: var(--wp--custom--button--outline--hover--color--text, var(--wp--custom--button--color--text));
  background-color: var(--wp--custom--button--outline--hover--color--background, var(--wp--custom--button--color--background));
}