But at times inside a web page we want the value of width to be something else and we want the Font size to be something else, which value is dynamically set by the user. So how does one do this inside the web page?
I mean what do we add to this to tell it that width for example should be 350 and font-size should be 14 Pix?
You could add a class to that and tell it font size and width.
Although perhaps it would be more useful to you (I don’t know your setup) to remove the width/fonts on that universal class and then add a class/classes to those elements to set width/anything that can vary between elements.
It would be good to give a clearer explanation of your situation. Is this being done via a CMS? You can place styles inline (at the point where they apply), in the header of the page (via style tags) or externally (via link tags). The external method is the easiest in terms of them being universally applicable.
Can you be specific with actual code for this?
I mean what is he exact code to change few elements of a CSS class
inside the web page?
BTW, the way we need to change these values inside the web page is because they are selected by the user in real time as they are viewing that
page. So in real time they can for example select to change the font
and background of a page.