The text in my popup box has disappeared (featherlight)

Hello!

I've set up a popup lightbox with text using the featherlight code. It was working perfectly. I cam back to it a few days later after making some changes on other pages and now it's blank. I feel like there could be something wrong with my code. I know virtually nothing about code, so I'm completely stumped as to what the problem could be. Any help would be appreciated!

This is what I have in the content block:

<div style="display:none;">
<div id="more-questions"><h4 style="text-align:center;">Get in touch with us!</h4><p style="text-align:center;">We love talking sport and how to help you get more people playing.</p></div></div>

<div align= center><font color="347dd3"><a href="#" data-featherlight="#more-questions" data-featherlight-variant="fixwidth">Got more questions?
  </a></font></div>

And I have this in my page header:

<script src="//code.jquery.com/jquery-latest.js"></script>
<link href="//cdn.rawgit.com/noelboss/featherlight/1.4.0/release/featherlight.min.css" type="text/css" rel="stylesheet" />
<script src="//cdn.rawgit.com/noelboss/featherlight/1.4.0/release/featherlight.min.js" type="text/javascript" charset="utf-8"></script>

And this code injection in my Global header:

<script src="//code.jquery.com/jquery-latest.js"></script>
<link href="//cdn.rawgit.com/noelboss/featherlight/1.4.0/release/featherlight.min.css" type="text/css" rel="stylesheet" />
<script src="//cdn.rawgit.com/noelboss/featherlight/1.4.0/release/featherlight.min.js" type="text/javascript" charset="utf-8"></script>

I've also used Custom CSS:

.fixwidth .featherlight-content {
   font-family: "Poppins", sans-serif !important;
   font-weight: 500 !important;
   font-style: normal !important;
  color: rgba(26,26,26,0.7) !important;
   font-size: 16px !important;
   letter-spacing: 1px !important;
   line-height: 1.6em !important;
  text-align: centre !important;
  padding-top: 20px !important;
padding-right: 30px !important;
padding-bottom: 20px !important;
padding-left: 30px !important;
  border-radius: 10px !important;}