How do I create a circle or square with just CSS - with a hollow center?

Question

It should just basically be an outline of the square or circle - that I can style accordingly (i.e. change the color to whatever I want, change the thickness of the border,

Answer 1

You can use special characters to make lots of shapes. Examples: http://jsfiddle.net/martlark/jWh2N/2/

  

    
hollow square
    
□
  
  

    
solid circle
    
•
  
  

    
open circle
    
๐
  

Many more can be found here: HTML Special Characters