What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
You can inject this css to make the minute field and the hour field more visible:
Here's a guide on how to inject css: How to inject custom css
Also, here's a link to a cloned form where I tested the css: https://form.jotform.com/60408574519965
You can clone it to your account by following this guide: How to clone a form
Do let us know if you need further assistance.