Animations
⭐ https://animista.net/play/text/pop-up/text-pop-up-top
⭐ https://animejs.com/ (JavaScript)
⭐ https://codemyui.com/tag/click-animation/
⭐ https://www.minimamente.com/project/magic/
⭐ http://vivify.mkcreative.cz/
https://css-tricks.com/css-animation-libraries/
https://animate.style/
https://ianlunn.github.io/Hover/
https://shakrmedia.github.io/tuesday/
https://tholman.com/obnoxious/
Loaders / Spinners
https://loading.io/css/
SVG
https://svgartista.net/
Gradients and colours
CSSGradients
Name that colour
Background patterns
https://css-tricks.com/a-few-background-patterns-sites/
http://www.heropatterns.com/