Yes it is possible. You will need create a blank custom html module and press Enter key in it to go to next line, which actually is considered as a new paragraph. A <p></p> tag is created by default, for every paragraph. You can adjust these as you want, later.
then in your template.css, add <blockquote>#ja-slideshow{
background: #colorcode;
}</blockquote> to have some colored background where the slideshow module is placed..
After this, check the page where you have a slideshow module, to confirm that whatever color you have given to ja-slideshow does not make your slideshow look bad.