A bunch of custom CSS has just randomly stopped working

Site URL: https://hellococo.ca/

Hello!

Went to open up my calendar to allow for some new booking dates and a bunch of my CSS that has been untouched for months and months has just randomly stopped working. I noticed a few days ago that my site title had changed the font colour to black from the usual colour but I figured that was an easy fix. Now navigating through the site I am noticing issues with almost every piece of CSS I originally added in February. Some of it is kind of half-working, with certain elements missing. Beyond frustrating! I'm a novice and it took me a long time to learn how to put it in properly the first time, don't even know where to begin fixing it.

First issue I'm noticing is my menu navigation hamburger on the mobile view is completely gone. When you hover where the hamburger used to be, the options drop down without the background colour so it's pretty unreadable.

On the home page, when you scroll down, where it says 'day by day' 'birthday' etc, it used to be big blocks with easy to read text. Now the blocks are gone and it's small and unreadable.

Some buttons disappeared.

The lettering on the home page- I tried to change it through site styles many times and it would not change until I hit 'upgrade' for their new drag and drop and then I was able to select a text colour. Is this causing the issue?

Some CSS like the custom scrollbar is unaffected. What gives!

If anyone has any idea on where to start recovering it would be much appreciated. Embarrassing to navigate a bunch of people to my site that was working completely fine for so long and discover it all in disarray.

Appreciate the help and have learned so much from these forums my first time around 🙂

If I remember correctly, there were some changes to selectors and that alot of color changes via CSS would need to be adjusted to the new selectors. This change requires more specific targeting.