function oeuvrediv() {
document.getElementById("oeuvre").style.display = "block";
document.getElementById("oeuvrelink").className = "beeldlinkactive";
document.getElementById("portret").style.display = "none";
document.getElementById("portretlink").className = "beeldlink";
document.getElementById("delft").style.display = "none";
document.getElementById("delftlink").className = "beeldlink";
document.getElementById("video").style.display = "none";
document.getElementById("videolink").className = "beeldlink";
videoframe.location.href = "dummy.htm"; 
}

function portretdiv() {
document.getElementById("oeuvre").style.display = "none";
document.getElementById("oeuvrelink").className = "beeldlink";
document.getElementById("portret").style.display = "block";
document.getElementById("portretlink").className = "beeldlinkactive";
document.getElementById("delft").style.display = "none";
document.getElementById("delftlink").className = "beeldlink";
document.getElementById("video").style.display = "none";
document.getElementById("videolink").className = "beeldlink";
videoframe.location.href = "dummy.htm"; 
}

function delftdiv() {
document.getElementById("oeuvre").style.display = "none";
document.getElementById("oeuvrelink").className = "beeldlink";
document.getElementById("portret").style.display = "none";
document.getElementById("portretlink").className = "beeldlink";
document.getElementById("delft").style.display = "block";
document.getElementById("delftlink").className = "beeldlinkactive";
document.getElementById("video").style.display = "none";
document.getElementById("videolink").className = "beeldlink";
videoframe.location.href = "dummy.htm"; 
}

function videodiv(j) {
document.getElementById("oeuvre").style.display = "none";
document.getElementById("oeuvrelink").className = "beeldlink";
document.getElementById("portret").style.display = "none";
document.getElementById("portretlink").className = "beeldlink";
document.getElementById("delft").style.display = "none";
document.getElementById("delftlink").className = "beeldlink";
document.getElementById("video").style.display = "block";
document.getElementById("videolink").className = "beeldlinkactive";
videoframe.location.href = j+"/vermeervideodiv.html"; 
}