is it possible to specify different borders for different sides?? If possible ,then how?

Answer 1

Yes: you have to specify the differents values in a special order, each one separated by a space... Order is clockwise, starting at top side if 4 values provided. If 3 values, the middle one is for horizontal sides (left and right), top first, bottom last, and 2 for vertical (top and bottom) first and horizontal last; obviously, once value set for all four borders ^^

Answer 2

Yes, you can possibly set borders of different sizes , colours for different sides
You can use border-top border-right border-bottom border-left to set borders to different sides according to your choice.

eg. border-left:1px solid #000;
border-right:2px dotted #fff;

Or more preferably, Yes! You can combine all those border things in just one border property as taking border-top as first argument and then going counter clockwise to border-left

for eg. border:(1px solid #333) (2px solid #000) (1px solid #333) (2px solid #000);

this will set top and bottom border with #333 colour and 1px size and right and left borders with #000 and 2px