function selectTab(tabName) {
document.getElementById( Overview ).style.display = “none”;
document.getElementById( Specs ).style.display = “none”;
document.getElementById(tabName).style.display = “block”;

switch (tabName) {
case “Overview”:
document.getElementById(“btnOverview”).className = “active”
document.getElementById(“btnSpecs”).className = “button”
break;
case “Specs”:
document.getElementById(“btnSpecs”).className = “active”
document.getElementById(“btnOverview”).className = “button”
break;
}
}

document.getElementById(“btnOverview”).click();