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Filter: bricks/link_css_selectors

Use this filter in your child theme to overwrite/extend the CSS selectors the “Theme Style > Link” settings are applied to like this:

add_filter( 'bricks/bricks/link_css_selectors', function( $link_css_selectors ) {
    // Add CSS link styles to .my-custom-element a
    $link_css_selectors[] = '.my-custom-element a';

    return $link_css_selectors; // Array of selectors the link styles are applied to
} );