How to change css dynamicaly without using javaScript

How to change css dynamicaly without using javaScript

[html]
[head]
[title]Change CSS Class[/title]
[style type="text/css"]
.ClassOut
{
background-color: black;
color: white;
font-weight: bold;
}

.ClassOver
{
background-color: white;
color: black;
font-weight: bold;
border: 1px solid black;
}
[/style]
[/head]
[body]
[p class="ClassOut" onmouseover="this.className='ClassOver';"
onmouseout="this.className='ClassOut';"]
Hi, I am a paragraph with text. If you hover your mouse
over me, my color changes . This is done by setting the
className CSS property.
[/p]
[/body]
[/html]

Thanks
HeelpOnDesk Team