4 Corners

-moz-border-radius: 20px;
-webkit-border-radius: 20px;
-khtml-border-radius: 20px;	
border-radius: 20px;
         

Top Left - Bottom Right

-moz-border-radius-topleft: 20px;
-webkit-border-top-left-radius: 20px;
-khtml-border-radius-topleft: 20px;	
border-top-left-radius: 20px;

-moz-border-radius-bottomright: 20px;
-webkit-border-bottom-right-radius: 20px;
-khtml-border-radius-bottomright: 20px;	
border-bottom-right-radius: 20px;
         

Bottom Left - Top Right

-moz-border-radius-topright: 20px;
-webkit-border-top-right-radius: 20px;
-khtml-border-radius-topright: 20px;	
border-top-right-radius: 20px;         
         
-moz-border-radius-bottomleft: 20px;
-webkit-border-bottom-left-radius: 20px;
-khtml-border-radius-bottomleft: 20px;	
border-bottom-left-radius: 20px;
         

Asymmetric Corners


You can easily try different variations and experimental shapes.

Asymmetric Corners


You can even try circular borders.

Circle


Or create a full circle