Como Hacer Una Columna En Excel

Hey guys and gals, I'm wanting to know if there is a way to change the arrows that seem to be default and the only option when you select the 'reel slideshow' in version 7.1.
I'd like to change them to the more minimalist style arrow available though the other gallery options slideshow full & simple & not have the transparent box that backs it.
(I've attached a picture of the section on my website and the default arrows that it comes with.)
Thank you in advance for anyone who has the answer!

Lily
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