Blurry images in Fluid Boxes - Responsive Project

[hayleyc14243818]

Hi all, I'm trying to find a solution for how to make my fluid box image fills look clear on mobile as well as desktop. I'm working in a responsive project in Captivate version 11.5.0.

The images look fine on desktop but get blurry on smaller screens. I'm using .png images as background fills for fluid boxes. The fluid boxes are set to be Centred tiles so the image automatically crops down on a mobile screen. But the image also gets blurry.

From what I've read, it would be best to use vector images rather than .png's but I've been unable to apply a vector image as a fluid box image fill. Does anyone have any recommendations to avoid the blurriness on mobile please? 

[Lilybiri]

Fills for fluid boxes are limited to bitpam images. That means no SVGs are psosible. Do you keep the ration widht/height?

[hayleyc14243818]

Thanks Lilybiri, that's what I found when I tried with an SVG. What do you mean by keep the ratio width/height? Is there a checkbox somewhere that I've missed?