If you want to learn WP Theme Development, you need to start with the basics:
Step one in WP Theme Dev is learn template hierarchy
These cheatsheets will come in handy during your work
Learn them well, try to delete large chunks of code and see which one’s which in your localserver (use XAMPP, it’s easier and less-bugged interface). Read more…
box-shadow property allows designers to easily implement multiple drop shadows (outer or inner) on box elements, specifying values for color, size, blur and offset.