CSS Layout Models
CSS Grid
https://cssgridgarden.com (opens in a new tab)
https://gridbyexample.com/examples (opens in a new tab)
https://learncssgrid.com (opens in a new tab)
https://css-tricks.com/snippets/css/complete-guide-grid (opens in a new tab)
https://css-tricks.com/responsive-grid-magazine-layout-in-just-20-lines-of-css (opens in a new tab)
Flexbox
https://flexboxfroggy.com (opens in a new tab)
https://yoksel.github.io/flex-cheatsheet (opens in a new tab)
https://css-tricks.com/snippets/css/a-guide-to-flexbox (opens in a new tab)
https://developer.mozilla.org/en-US/docs/Learn/CSS/CSS_layout/Flexbox (opens in a new tab)
https://polypane.app/blog/4-css-layouts-without-using-media-queries (opens in a new tab)