<!DOCTYPE html> <html lang="en"> <head> <title>Change iFrame Border Using CSS</title> </head> <body> <h2>Solid Border With Blue Color</h2> <iframe src="examples/resources/sample.htm" style="border: 4px solid blue;"></iframe> <h2>Dotted Border With Red Color</h2> <iframe src="examples/resources/sample.htm" style="border: 2px dotted red;"></iframe> </body> </html>