function tabdefault() {
    document.getElementById("first_tab").className = "tabhover";
}

function firsthover() {
    document.getElementById("first_tab").className = "tabhover";
    document.getElementById("tabone").style.display = "block";

    document.getElementById("second_tab").className = "noton";
    document.getElementById("tabtwo").style.display = "none";

    document.getElementById("fourth_tab").className = "noton";
    document.getElementById("tabfour").style.display = "none";

    document.getElementById("third_tab").className = "noton";
    document.getElementById("tabthree").style.display = "none";
}

function secondhover() {
    document.getElementById("second_tab").className = "tabhover";
    document.getElementById("tabtwo").style.display = "block";

    document.getElementById("first_tab").className = "noton";
    document.getElementById("tabone").style.display = "none";

    document.getElementById("fourth_tab").className = "noton";
    document.getElementById("tabfour").style.display = "none";

    document.getElementById("third_tab").className = "noton";
    document.getElementById("tabthree").style.display = "none";
}


function thirdhover() {
    document.getElementById("third_tab").className = "tabhover";
    document.getElementById("tabthree").style.display = "block";

    document.getElementById("first_tab").className = "noton";
    document.getElementById("tabone").style.display = "none";

    document.getElementById("fourth_tab").className = "noton";
    document.getElementById("tabfour").style.display = "none";

    document.getElementById("second_tab").className = "noton";
    document.getElementById("tabtwo").style.display = "none";
}

function fourthhover() {
    document.getElementById("fourth_tab").className = "tabhover";
    document.getElementById("tabfour").style.display = "block";
    
    document.getElementById("third_tab").className = "noton";
    document.getElementById("tabthree").style.display = "none";

    document.getElementById("first_tab").className = "noton";
    document.getElementById("tabone").style.display = "none";

    document.getElementById("second_tab").className = "noton";
    document.getElementById("tabtwo").style.display = "none";
}