function zeigemenus1() {
document.getElementById("link1").style.visibility = "visible";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus2() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "visible";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus3() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "visible";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus4() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "visible";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus5() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "visible";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus6() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "visible";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus7() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "visible";
document.getElementById("link8").style.visibility = "hidden";
}

function zeigemenus8() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "visible";
}

function loeschen() {
document.getElementById("link1").style.visibility = "hidden";
document.getElementById("link2").style.visibility = "hidden";
document.getElementById("link3").style.visibility = "hidden";
document.getElementById("link4").style.visibility = "hidden";
document.getElementById("link5").style.visibility = "hidden";
document.getElementById("link6").style.visibility = "hidden";
document.getElementById("link7").style.visibility = "hidden";
document.getElementById("link8").style.visibility = "hidden";
}