How to fix the Thank you page's cut off?

Hi, after submitting the form, the thank you page shows, however the bottom of the border is not showing correctly and I was hoping to find out how to fix this.

I inserted the below CSS code in your Custom CSS Field of your form:

.thankyou {

    height: 400px!important;

}

And that should fix your Thank you page.

Please try and let us know how it worked.

Thank you!

Thank you, it worked! :)