Cannot pick a color with a HEX value

Steps to Reproduce

1. open the background color button on the toolbar
2. enter a hex value in the input

Current Result

Expected Result

it changes the color upon the input hex value

Debug Information

• missing related code
• zss.Colorpicker is not a zk widget, and it creates functions in its constructor which is hard to override. It's better to refactor the structure when fixing this bug.