Squarespace site NOT working well with safari browser

I've been experiencing several issues with my Squarespace site functioning on Safari's browser. (For some background) I designed the site using Chrome, and everything has been working just fine. However, when we check how the site looks using Safari's browser, there are quite a few things that don't work properly...

• The video on the top of the "Who we are" page glitches completely and gets all pixelated.
• Further down the "Who we are" page features some images that are custom-coded with a hover state to flip around when you hover over them. After hovering over them twice, the images completely disappear. Again, on Chrome's browser, this is not an issue but on Safari it is.
• Some GIF files don't work. For example, on the Portfolio page, we have a project (Fabcon) that has a GIF as the featured image and it doesn't show up at all.

Here is the link to our site: https://www.freethinkingforhire.com/who-we-are

Has anyone else experienced issues with their Squarespace sites functioning correctly on Safari's browser?

#2. Which code did you use? Sometimes you will need to add pre-fix to make it works on all browsers.

I usually use this tool to add prefix: https://autoprefixer.github.io/

I am dealing with this issue now too. On Safari, my hyperlinks don't switch on hover. They are supposed to be underlined blue and then switch to very dark blue on hover. 

https://gardenia-pumpkin-ekbe.squarespace.com/homebuying-incentive

code: 1234

I've tried adding in !important and adding in the web-kit prefix.

a {
 -webkit-text-decoration-color: #1ABFDC;
text-decoration-color: #1ABFDC !important;
  text-decoration-thickness: 2px !important;
}

a:hover {
  -webkit-text-decoration-color: #07263E !important;
  text-decoration-color: #07263E !important;
}