Updating background colour

Hello,

First of all thanks a lot for this great plugin, I am however confronted with a minor issue.

The plugin works fine but whenever I try to update the quantity, the “Continue” button turns into “Udpating” which is perfectly normal, BUT the background colour turns purple instead of its original transparent background.

I’ve tried to change the spinning wheel colour and the theme colour on wordpress is the same as my website colour, but the problem remains.
I’m using the Divi theme.

Please let me know what steps to take in order to rectify this issue.

Here’s a screenshot of what i’m describing : https://i.imgur.com/haYn4ed.png

Thanks a lot.

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