Gracias, ya funciona!
He intentado hacer uno por mi cuenta y no me funciona, alguien sabe en que me he equivocado???
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<html>
<head>
<script language="Javascript">
function mostrar() {
var layer1, mostrar;
layer1 = document.getElementById("layer1");
if(layer1.style.visibility == "hidden") {
layer1.style.visibility = "visible";
mostrar = document.getElementById("mostrar").childNodes[0];
mostrar.data = "Ocultar";
}
else {
layer1.style.visibility = "hidden";
mostrar = document.getElementById("mostrar").childNodes[0];
mostrar.data = "Mostrar";
}
}
</script>
</head>
<body>
<div id="Layer1" style="position:absolute; width:200px; height:115px; z-index:2; background-color: #0033FF; layer-background-color: #0033FF; border: 1px none #000000; left: 44px; top: 22px; color: #FFFFFF; visibility: hidden;">un poquito de porfavor </div>
<div id="Layer2" style="position:absolute; width:173px; height:160px; z-index:3; left: 458px; top: 23px; background-color: #990000; layer-background-color: #990000; border: 1px none #000000; visibility: visible;"><a id="mostrar" href="javascript
:mostrar();"><img src="mis%20cosillas/Nota.png"></a></div>
</body>
</html>
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