How do I make the div stay there until the link is clicked again?

[kokzvw]

I'm trying to make a sidebar that only appears when a triangle is clicked and I've gotten to the point where you click the triangle and it appears using:\[code\]sidebar {display: none;}a:active + .sidebar { display: block;}\[/code\]However as soon as you let go it disappears. How can I make it stay visible until you click the triangle for a second time? Below is the link to full code.http://jsfiddle.net/Vqmaw/