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<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <style> h1 {font-size: 1.2cm;} h2 {font-size: 1cm;} p { font-size: 0.4cm; line-height: 1cm; } b { font-size: 1cm; } </style> <script>var clicky_site_ids = clicky_site_ids || []; clicky_site_ids.push(101319977);</script><script async src="//static.getclicky.com/js"></script></head> <body> <h1>CSS Units.</h1> <h2> CSS cm absolute unit </h2> <p>I am 0.4 cm font-size</p> <b>I am 1cm absolute length unit</b> </body> </html>