Button expanding on click

Hi, just installed the plugin and it is working fine except for this – when the button is clicked there is firstly quite a long delay before the form appears, and secondly (and more important for me) the button appears to get padding inserted on the left so the text moves to the right and the button expands with it when clicked, which looks very odd. I have tried to find what is causing this but I am finding it very difficult to find what it might be, as I can’t isolate with the inspector due to it being only when the button is clicked. In addition, I have set the button to change text and background color on hover which works, but when clicked those colors remain and the button does not go back to its initial state until another mouse click is made somewhere on the page. Functionally the button is perfect, but if you can advise on where in the plugin css these issues might be caused, or any other tips I’d be very grateful. I obviously realise it might be the theme (Blocksy) but there is a lot more css to wade through there!