Question

For example when I copy the link from an answer and access it, a nice block of color appears to highlight the answer and then is fading out. How this is done?

Answer 1

It looks at the hash, selects that answer, and then animates the background color. Either use jQuery UI or add the Colors plugin to be able to animate colors.

This is what the code may look like…

var hash = window.location.hash;

if (hash) {
   var answer = $('#answer-' + hash.substr(1)),
       originalBackgroundColor = answer.css('backgroundColor'); 

   // This class changes the background colur.
   // Best to keep style stuff in the CSS layer.
   answer
   .addClass('linked')
   .animate({
       backgroundColor: originalBackgroundColor
   }, 1000);

   // You may optionally remove the added class
   // in the callback of the above animation.
}