Jquery Chart sits on top of text rather than underneath - how to fix?

Question

I have a page that has a jquery chart on it (JQPlot). Unfortunately for some reason the chart sits on top of the text on the page, rather than directly underneath it.

Does anyone have any idea how to amend this - I have been scratching my head for hours and cannot seem to find out why it is doing it.

Webpage is here http://www.healthinteractive.co.uk/assess/node/3/done

Thanks in advance