<!DOCTYPE html> <html lang="en-US"> <head> <title>border-image-width: 1em reference</title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <meta http-equiv="Content-Style-Type" content="text/css"> </head> <body> <div style="border: solid #1DD813 2em"> <div style="margin: -1em;"> border.png<br />second longer longer longer longer longer longer line<br />third longer longer longer longer longer longer line </div> </div> </body> </html>