Apply Style i.e Hanging Indent on selected paragraph rest p

Question

I making an html editor in Win form using web browser control .
I have to apply style on Selected Para (p tag) [ Getelementbytagname("p")].
Have got the selected P tag using" mshtmltextrange" from the document now i have get all the style element of the paragraphs one by one and if it have certain style i.e-Text-Indent:-15 Px or Margin-left:15 Px (This Style is Basically for Hanging Indent can be other also) or else style we have to retain it and add the value to it if further clicked .