Step 1:
Navigate to WordPress Admin Dashboard > Appearance > Customizer > Hostiko Customizer > Live Chat > Apply Style.
Step 2:
Change the toggle button to Yes.

Step 3:
To change the Background color search for Background Color.

Step 4:
To change the color search for Color.

Step 5:
To change the border color search for Border Color.

Step 6:
To change the border radius search for Border Radius.

Step 7:
To change the Cart Hover background search for Background Hover Color.

Step 8:
To change the Cart Hover Color search for Hover Color.

Step 9:
Click on Publish once you are done with all of changes.