alt Hacker NewsHmm. by kashida do you mean something like 'ایـــــــــــــن'?
I don't think you mean this, because I don't know how would you do it in CSS. Looks more like a problem to be solved with different types of character than styling.
You may want to explain more.
there was some attempts to make this happen back in the days. see text-kashida-space. if drop letters are something CSS can own, why not kashida?