CSS Links
Generators - are programs that generate code for you.
Some of the easiest are Websites that generate code you can cut + paste into your own CSS files.
They are usually very visual - with buttons to select features and drag bars to increase or decrease features.
They come in every shape and size and the list of them grows every day. Here are some that I found interesting today.
But I encourage you to look for others - Google "CSS3 Generators" or "Bootstrap Generators"
CSS3 Generators
Button Generator https://css3gen.com/button-generator
Various CSS3 Generators https://css3gen.com
Color Generators
Color Zilla http://www.colorzilla.com/gradient-editor
Bootstrap
Theme Generator https://pikock.github.io/bootstrap-magic/app/index.html#!/editor
Table Generator https://www.tablestrap.com/#tables
Tables - Tables are great for organizing data - but they are not by default responsive ... this one is!
Responsive Table Generator http://ianrmedia.unl.edu/responsive-table-generator-tool
Interesting Links
CSS Image Gallery https://www.w3schools.com/css/css_image_gallery.asp
CSS Animations http://animista.net
W3Schools HowTo (It's more than just CSS) https://www.w3schools.com/howto
Free Computer Courses https://www.freecodecamp.org/news/free-online-programming-cs-courses/