CSS Switchers

Awsm

Colors Switcher

Dropin Minimal CSS

Geeks for Geeks

Html5 Elements Tester

W3.org - Multiple CSS Switcher

W3.org - Colors & fonts

W3.org - CSS Frameworks CDN Switcher

W3.org - Ma version

CSS frameworks switcher

Main CSS Frameworks with CDN

Classless CSS Frameworks with CDN