Magic Radio Buttons 介绍
Allows one to replace a radio button’s default selectors with images for
‘selected’ and ‘unselected’
1) Radio buttons need their own id - this is to attach them to the label.
2) Currently the css controls the display (padding for ffox, height/width for
ie) and the image url (eg which image is open/active).
Test.html is a basic test page.