Code:
<HTML>
<HEAD>
<TITLE>Testing</TITLE>
</HEAD>
<BODY>
<H1 class="Main" style="color:red;">Testing
<H1 onclick='document.classes.Main.all.color="green";'>sdsddsd
</BODY>
</HTML>
when click on sdsddsd. the testing word should change color. why when I test it. it's show error ?