CSS Frameworks

Core

• Bootstrap
• Foundation
• Bulma
• Semantic
• Materialize
• Skeleton
• Pico

Themes

• NES
• Geo for Bootstrap
• Windows 98

Gradients

• 3-color-gradient

Examples

checker box background

Thanks to: https://twitter.com/lyle/status/1395480240978161664?s=21

background:
  repeating-conic-gradient(#505050 0% 25%, #909090 0% 50%) 50% / 30px 30px;