<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>Font Size Issue with Viewport Units</title> <style> html { font-size: calc(1em + 2vw); } h1 { font-size: 2rem; } </style> </head> <body> <h1>Hai friends..</h1> <p>How are you...</p> </body> </html>