Also I am testing the designer feature now, and I can see that it has flaws. if you check the image below you can see despite of setting background color and border etc the white box still remains in the search box.
You’re right, that looks like a bug in the Powerpack designer. Your customizations aren’t affecting the actual search field. You can add this CSS as a work around in Appearance > Customize > Additional CSS:
.widget_product_search form:not(.wp-block-search) input[type=search] {
border-radius: 16em;
border: 1px solid #FF0101;
background: #0101FF;
}
As this isn’t related to the Storefront theme, if you have any further questions about the Powerpack extension, please contact us at WooCommerce.com > My Account > Support. You may need to create an account before you can access that page.
Please include a link to this forum thread, so that we can keep track of what’s already been done.
We will be able to help you further there.