While there is no built in way to modify the default Styles: normal, Heading 1, Heading 2, etc; after much research I discovered a fairly easy way to get this to happen. Just add this code to the, "Chapter CSS" window. Notice too, this code Center Aligns the Heading 1 font.
text-indent: 25px ;
PLUS: once you understand how this is done, it is very easy to look up other CSS commands and redefine the default built in Style.