Chris Staudinger on X: "CSS em vs rem explained 🎨👇 Both em and rem are relative units of measurement used in frontend development. em is relative to the font size of the
CSS Font-Size: em vs. px vs. pt vs. percent / Kyle Schaeffer
Font Sizes: Pixels = Rem Values
CSS units: em, rem, and px – Cody Loyd
The Battle of the Units: PX vs REM vs EM (font-size) - DEV Community
Understanding CSS Units (PX, EM, REM) and how to use them. – Amey Raut
How using [rem] can help you to build excellent mobile-first applications