about 2D box collider

Hello , I m new to unity game development, I m trying to create simple collide game with player and platform.
my question is when I add Box Colilider2D component to platform I cant Scale . I did try pressing SHIFT key did not work. (Im using UNITY 5)
Can anyone help me?
thanks

 

Afternoon, i take it you want to scale the collider?
when adjusting the scale of the collider there is a button for 'Edit Collider' just next to it on the inspector.
if you press this you can see the collider handles and adjust from there.