I did it but now it shows an ERROR message (Unexpected symbol) at this line:"color: @c_text;" and "font: @f_title;". It works if I write an RGB code like "$182850;" but what am I supposed to write here: "font: @f_title;"?
and ends like this:
I get this:
EROOR at line 6 pos 28: Unexpected symbol in expression.
Your code is missing the quotation marks around the entire file. The second argument needs to be a string. Make sure you only use one kind of quotation mark (" vs ') in your window file, and use the other quotation marks to surround the entire block of text.
Note that you do not need to create any fonts or change the way the colors are written.