Code:
<html>
<head>
<script language="javascript">
function moveMarker() {
marker.style.display='block'
marker.style.left = event.clientX - 2
}
</script>
<style type="text/css">
.header {
width:100px;
border:1px solid black;
border-top:none;
text-align:center;
font:12px arial
}
#marker {
width:10px;
font-size:3px;
border:1px solid black;
background:silver;
position:absolute;
top:15px;
display:none
}
#line {
width:500px;
font-size:3px;
border:1px solid black;
background:rgb(200,220,200)
}
</style>
</head>
<body>
<div id="marker"></div>
<div id="line"></div>
<span class="header" onmousemove="moveMarker()" onmouseout="marker.style.display='none'">
Header 1
</span>
<span class="header" onmousemove="moveMarker()" onmouseout="marker.style.display='none'">
Header 2
</span>
<span class="header" onmousemove="moveMarker()" onmouseout="marker.style.display='none'">
Header 3
</span>
</body>
</html>
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