Customization | Marketo form for Wistia

Hi all, 

I'm having difficulties with Wistia to customized Marketo forms in a video. I'm aware that I have to update in Marketo CSS form, but I didn't manage to fix all structures. 

1 - If I add a subject in Wistia like "Fill up the form....", it creates additional space. It doesn't look very nice. Any idea how could I fix it in Marketo or Wistia?

I know I could add in Marketo a rich text field, but it doesn't look great either...

2. I didn't manage to remove an extra scroll bar in the footer.  Any ideas? 

3. Also, how can I display fields side by side in Wistia? It is placed like the image below in Marketo but it doesn't replicate to Wistia.

Thanks.

Andreia