I wanted to add checkboxes to my step-by-step instructions in Wordpress, but wordpress.com does not allow form elements or Javascript on its free blog sites. The checkboxes would be used to check off the completed step.

I was looking at CSS transitions. Perhaps a change from one color to another would suffice. But the w3 examples show a change from size or color on hover, then they revert back. Is there a way to change the state of something via CSS, and stay in that state for the duration of the browser session?