how to change the fonts family of the webui interface?

[saccleo]

The characters on the webui do not looking fine in my mother tongue. If I chose English, all look fine.
If I force the browser use the default font family and ignore the that declared by asuswrt webui, it also works fine.
So it may related with the font family declared in the asp or html files.
How can I change it? Change the files and recompile the firmware?
thanks a lot!