To change the style of the pieces, add this to the end of the URL:

&piece_style=style

The styles are all derived by chess fonts created by Armando Hernandez Marroquin and distributed as "freeware."

The default style is merida. These are the available styles:

adventurer		alfonso
cases		condal
harlequin		kingdom
leipzig		line
lucena		magnetic
mark		marroquin
maya		mediaeval
merida		motif