On the other hand, if all that style stuff is the same in each chapter - or you don't mind a few errors
- you can do a cut from one chapter and paste into a stylesheet.css file, then replace all those stylestuffs in each chapter with a link to your stylesheet file. And add in some linefeeds to make it easier for you to read...
And if the book doesn't have all those fonts included you can get rid of the @fontface statements - but the font-family bits in the stylesheet should be changed to serif for the Goudy and sans-serif for the Helvetica (and I'm not sure what the Janson should be - maybe embed your own distinctive font?)
Now isn't all that really more work than it's worth? As DSpider says, most ereaders can sort out some pretty ugly input files. (I have at least one book where all that styling stuff is embedded within the html text, not even gathered into a style section.) On the other hand, if what you're looking at on your ereader is ugly, you may feel it's worth the trouble.