Image block: how to add hyperlink underline and having both image and button hyperlinks

Site URL: http://www.waterfall-gallery.com

Help me to...

Option 1: Add a link both when clicking the image and on button for image blocks. In the default setting, I can only choose one or the other.

Option 2: Add an underline on the hyperlinked text (Learn More). The Design setting for Image Blocks does not have option to show underline for hyperlinks.

Please HELP!!

#1. Add a text link in Subtitle, then we can give the code to make the link cover whole block (then use code to make text transparent color)

#2. Add to Design > Custom CSS

.image-subtitle p:last-child a {
    text-decoration: underline !important;
}