Youtube lightbox

Hello, I would like to be able to edit the borders and section shapes under the form editor, at the moment, the options I have a very limited, leaving a lot of blank space between the header and the youtube frame in addition to a lot of blank space in the border. Can you help and point me in the right direction how to edit this to make it a little bit move even?

You can reduce line spacing and vertical padding inside of Advanced Designer.

Here is my demo form: https://form.jotformpro.com/71375186671968 

Hope this will help. Let us know if you need further assistance. 

Thank you for getting back to me so promptly, can you please let me know
who to reach the advanced designer? Is it reserved only for paying
customers? The way I am doing it is through Publish> Embed > Lightbox
option. Do not see advanced designer options...
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To access to the Advanced Designer, inside of the Form Builder click on Form Designer icon. 

Then click on the Advanced Designer button, the is located at the bottom of Colors tab.

Hope this will help. 

This is so helpful! Thank you so much, I feel stupid :).
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