تعویض Background

[bahy_my]

سلام
خوبین ؟

<style>

.class1{
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.
background-image:url(file.jpg);
.
..
...
}

</style>
<script>


function ch_bg(id, c_name){
	tg=document.getElementById(id);
	tg.className=c_name;
}


</script>
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.

<td id="td1"><span onmouseover="ch_bg('td1','class1');">Home</span></td>
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