Post-submit "thank you" not showing up

Nothing loads on button click – just a blank space. I tried fixing it with this to force color and size, still nothing:

.newsletter-block .form-submission-text { font-size: 20px; color: #1E4C90;}

The site is brooklynmeditation.org and the form is on every footer. I have some custom CSS for .newsletter-block .newsletter-form-button but I dont think there's anything there that could affect the post-submit message...

Thanks everyone!

Also wondering about this. How do you increase the font size for post submit message font size? 

The new squarespace forums suck btw... Whenever I google search a question and click a forum link it sends me to the front page!

Enter the message in the Post-Submit HTML box instead. You can add HTML code to display along with the Post-Submit message. For example:

<h2>thank you</h2>

Same problem here, it's just a blank page after hitting the Submit button. Tried Paul's HTML suggestion as well, no dice.

1 minute ago, khomatech said:

Same problem here, it's just a blank page after hitting the Submit button. Tried Paul's HTML suggestion as well, no dice.

My suggestion was in response to the question "how do you increase the font size?"  It won’t help if you can’t see post submit text. Check that your font colour isn’t the same as the background. If that’s not the issue, post a link to the page or contact Squarespace Customer Care.