function showTab(tab) {

      
    var propertiestab = document.getElementById('propertiesTab');
    var destinationGuideTab = document.getElementById('destinationGuideTab');
    
    propertiestab.className = 'displayNone';
    destinationGuideTab.className = 'displayNone';

    document.getElementById(tab).className = "";

    if (tab == 'propertiesTab') {

        document.getElementById('spanProperties').className = "containerTab On";
        if (document.getElementById('spanDestinationGuide').className != "displayNone") {
            document.getElementById('spanDestinationGuide').className = "containerTab";
        }
    }
    else {

        if (document.getElementById('spanProperties').className != "displayNone") {
            document.getElementById('spanProperties').className = "containerTab";
        }
        document.getElementById('spanDestinationGuide').className = "containerTab On";

    }
}