customize web page for client user for WHD?

What are you meaning about customize?

Options display / not display depending on what has been setup by your Admin.

I think they want to change the layout and CSS code of the client web portal. You can edit the CSS look in the CSS directory on your server, but the layout is hardcoded.

yes. I want to change the layout of the client's website.

if you don't mind, can share with me how to go to hardcoded?

yes. I want to change the layout of the client's website.

if you don't mind, can share with me how to go to hardcoded?

Hardcoded - fix (data or parameters) in a program in such a way that they cannot be altered without modifying the program.