Video Embed and Youtube Blocks Not Working

Hi,

Guttenberg Embed and Youtube blocks are working on the back end but aren’t showing up on the front end anymore (previously they did).

The Youtube block is placed about 2/3rds down the page, right after “If not, then do yourself a favor and check out this introduction to the art (and introductory course) by legend Dirk Ercken (not affiliated):”

Adding the following snippet of CSS, as recommended in other posts on this topic, doesn’t help:

.wp-embed-responsive .wp-block-embed .wp-block-embed__wrapper:before {
position: relative;
}

However, removing the following snippet, given to me in another thread on this forum to help with a sizing issue, does fix the problem:

@media only screen and (max-width: 669px){
.wp-embed-responsive .wp-embed-aspect-4-3 .wp-block-embed__wrapper:before {
padding-top: 0;
}

Removing the latter snippet causes videos to be full-width, no matter the screen size, which doesn’t work with my site.

Thanks in advance for any suggestions!

The page I need help with: [log in to see the link]