Change colour behind header logo

[sarcuk]

Hi, I have successfully changed the colour of my header and have my logo at the correct size and position. However there is a white box behind my logo on larger screen sizes. I have searched the stylesheet for the appropriate code to change. Can someone help put me in the right direction?
https:/ /www. sarcoidosisuk.org/ shop/
Thanks

[Basara]

I did not see any white box even on 2300 px width screen. Clean the browser cache or post screenshot

[sarcuk]

I had thought I had cleared cache but clearly not. All looks good. Thanks for your help