Change color button of the research bar

Hi there,

I can’t change the background color of the research button (see end of the homepage where it appears pink although other buttons such as the end of this page https://alizelj.wordpress.com/?p=612&preview=true&_thumbnail_id=615 appear with #c08b3cff). I did change successfully the background color of buttons in the Styles tab but changing the background of the Research bar just provides another background at the back of the actual button without changing the main color. At least the color still appear pink in the published website but in my “site editor”, it looks correctly changed to #c08b3cff. I have no access to the CSS since I’m still trying out stuff. Anyone with the same issue that found a solution to it?
Thank you!

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