var currentPageBtn = btnHome;

function changeNavigationClassToFocused(id) {
    document.getElementById(id).className = "buttonFocused";
}

function changeNavigationClassToNormal(id) {
    if(id != currentPageBtn) document.getElementById(id).className = "button";
}

function setNavigationClass(id) {
    currentPageBtn = id;
    changeNavigationClassToFocused(id);
}