Aunque esto deberia pedirlo en javascript.
Código:
<title></title>
<script language="JavaScript" type="text/JavaScript">
function domTab(i){
//-- Variables para personalizar
var numberOfTabs = 5;
var colourOfInactiveTab = "#999966";
var colourOfActiveTab = "#cccc99";
var colourOfInactiveLink = "#333333";
var colourOfActiveLink = "#ffffcc";
if (document.getElementById){
for (f=1;f<numberOfTabs+1;f++){
document.getElementById('contentblock'+f).style.display='none';
document.getElementById('link'+f).style.background=colourOfInactiveTab;
document.getElementById('link'+f).style.color=colourOfInactiveLink;
}
document.getElementById('contentblock'+i).style.display='block';
document.getElementById('link'+i).style.background=colourOfActiveTab;
document.getElementById('link'+i).style.color=colourOfActiveLink;
}
}
</script>
</head>
<body bgcolor="#FFFFFF" leftmargin="0" topmargin="0" marginwidth="0" marginheight="0" >
<a name="top"></a>
<a href="#target1" onclick="domTab(1)" id="link1" class="tablink">Espicificaciones</a>
<a href="#target2" onclick="domTab(2)" id="link2" class="tablink">Foto</a>
<a href="#target3" onclick="domTab(3)" id="link3" class="tablink">Uso</a>
<a href="#target4" onclick="domTab(4)" id="link4" class="tablink">Mas</a>
<a href="#target5" onclick="domTab(5)" id="link5" class="tablink">Y Mas</a>
<div id="contentblock1" class="tab">
<a name="target1"></a>
1
</div>
<div id="contentblock2" class="tab">
2
</div>
<div id="contentblock3" class="tab">
3
</div>
<div id="contentblock4" class="tab">
4
</div>
<div id="contentblock5" class="tab">
5
</div>
</body>
</html>