How can I make the backgrond color transparent for my embedded form?

Dear,

I will do my best to explain my problem in English, I'm from Holland.

I've made a form and i'm quite satisfied about it. I adjusted several sections and the lay-out. 

One adjustment on the lay-out (via 'designer') I made was the background of the form. I want that only the textfields and buttons are visible but no background. I adjusted 'background' and 'frame' to nothing, but when I publish via iFrame it stays white. 

The funny thing is (as for me) that when I publish via source code or the direct link option it is transparent as it should be. 

I really want it in the iFrame version otherwise the htmlcode is so unclear. 

Can you help??!!?? :)

I have checked your form and I can see the white background showing on the iFrame embedded code; however, this can be fixed by injecting some CSS code, please inject this: 

.supernova {

    background-color: transparent;

}

Open the Designer and remove all the code you currently have there and paste the one I provided.

To open the Designer, first click on the Designer icon: 

Remove the code and paste the given code there on the CSS tab: 

Hope this helps.