Resources

Learning

MDN Web Docs
A great resource for learn HTML, CSS, JavaScript, and more!
Flexbox Froggy
A game to learn CSS flexbox layouts.
Grid Garden, Grid Attack
Games to learn CSS grid layouts.
Kevin Powell
I've learned so much about CSS this youtube channel, he rocks.

Tools

140 HTML Color Names
When I don't want to fuss with colours codes
Hex Color To CSS Filter Converter
Convert black images to a target hex color code with a generated filter. Great for transparent PNGs and SVGs!
Font Awesome
A resource for various icons all over my site, like social media icons, the back to top icon, and more! Lots of free options.
GifCities by the Internet Archive
A GeoCities animated GIF search engine
CodePen.io
Useful for practicing and workshopping code on my secondary devices when I just want to noodle around quickly on a secondary device.
clamp() Calculator by Chris Burnell
A resource for a very useful function that can reduce the need for media queries.

Things I Use (Or Have Used) On My Site

Insert Updateable Elements by kiophen
A way to insert external html into another html document. I also found I can add related javascript below the last line to have it work on the inserted html, something that didn't work using W3's Include-HTML script.
Pure CSS Tabs Using <radio> and <label> Tags by Joachim Kliemann
Switches between panels on a static page- doesn't create new history states when navigating between them.
Anchor Link JSFiddle
Uses links to toggle between visible divs- creates new history states by use of location hashes, for example: website.com/page#locationhash
Responsive equal height images with CSS by Nathan Nguyen
When I need images of different widths to have the same height in a row.
Animate <details> without JavaScript by jgustavo.wd
Used in conjunction with Transitioning to Height Auto using the grid approach.
Seamless Responsive Photo Grid by Chris Coyier
The guide I followed for my (last website's) responsive art galleries.
Lightbox2 by Lokesh Dhakar
A fully-featured lightbox for images!