Style="text-decoration:none" disappears


in the page “Journal sponsorship”, I need to add some logos, and to male them linkable.
By doing so, in “Immersion theme” I get them underlined by default by the theme, which is a very nice effect for the textual links indeed, but don’t work well for the images (the logo of the University becomes underlined, which is not the case).
So I tried to use the style=“text-decoration:none” tag in the view code option of the static page, but the editor keeps deleting it when I save the page.
Is there a way to avoid the editor to delete this tag? How could I avoid the images to be underlined, if linked?
Thank you very much