Ribbon Effect for Twenty Eleven Theme

I thought a nice ribbon would give some 3D feel to the navigation for The Chemistry Book. The idea was to get a ribbon without adding an image but to use pure CSS rules. In this case, the before and after.

The following code was added to a child theme for Twenty Eleven.

#access:after
{
content: ‘ ‘;
position: absolute;
width: 0;
height: 0;
left: -20px;
top: 212px;
border-width: 5px 10px;
border-style: solid;
border-color: #666 #666 transparent transparent;
}

#access:before
{
content: ‘ ‘;
position: absolute;
width: 0;
height: 0;
right: -20px;
top: 212px;
border-width: 5px 10px;
border-style: solid;
border-color: #666 transparent transparent #666;
}
[/code]