Tiny thing here, but values of 0 in CSS don't need units and a CSS linter will raise a warning about it. It doesn't affect anything, but it's a good practice to not include them. Here's a few spots where you have units attached to 0.

https://github.com/juliemi/tea-cozy/blob/master/resources/css/style.css#L2-L3
https://github.com/juliemi/tea-cozy/blob/master/resources/css/style.css#L70

You have done a great job on the organization of your HTML! The class names are specific, everything is nicely indented, and there's no areas of confusion. The is really readable and organized as well. This is some really good HTML!

Good work!

Indentation seems like a little thing, but early on a lot of new developers struggle with it and can get into bad habits. Your indentation is superb (even if I think the spaces are too large, which is just a editor setting). Very consistent and no wasted space. It's a small part of programming, practically non-existent in the minds of senior developers, but to get into good habits like you're setting now is excellent.

One suggestion might be including "section" comments in your HTML/CSS where each logical section of code starts. That makes the code more human readable when you're skimming through the code.