Anyway to change Lightbox form block colour?

Site URL: https://raspberry-coyote-6gss.squarespace.com/config/

I am looking to change my form block colour, it is in Lightbox mode and I was wondering if there was anyway to change the colour of the Lightbox? at the moment it is grey, but I would like it white 

Add to Home > Design > Custom CSS

/* Lightbox button */
button.lightbox-handle {
    background: red !important;
    color: violet !important;
}

4 hours ago, tuanphan said:

Add to Home > Design > Custom CSS

/* Lightbox button */
button.lightbox-handle {
    background: red !important;
    color: violet !important;
}

 

Thank you!

I see menu has 1 item + icon only. Do you want to force desktop menu on tablet + mobile?

How about a way to customize the design of the actual pop-up form? 

On 2/24/2021 at 10:49 PM, SproutDesignStudio said:

How about a way to customize the design of the actual pop-up form? 

Can you describe in detail? & Link to your site, we can help easier