<!DOCTYPE html> <html> <head><title>Red and Yellow</title> <style type="text/css"> <!-- #box { background-color: red; color:red; } --> </style> </head> <body> <p>鎌倉幕府は<span id="box" onclick="check();" onmouseout="red()">1192</span>年、</p> <script type="text/javascript" src="redyellow.js"> </script> </body> </html>