function changeFontSize(size) {

    // resize all paragraph, hyperlink, label, table header and table div contents
    var p = document.getElementsByTagName('p');
    var a = document.getElementsByTagName('a');
    var label = document.getElementsByTagName('label');
    var th = document.getElementsByTagName('th');
    var td = document.getElementsByTagName('td');
    
    for(i = 0; i < p.length; i++) {
        
        // do not alter the size of the feature title on the homepage
        if (p[i].className != "title") {
            p[i].style.fontSize = size + "px";
        }
    }
    
    for(i = 0; i < a.length; i++) {
        a[i].style.fontSize = size + "px";
    }
    
    for(i = 0; i < label.length; i++) {
        label[i].style.fontSize = size + "px";
    }
    
    for(i = 0; i < th.length; i++) {
        th[i].style.fontSize = size + "px";
    }
    
    for(i = 0; i < td.length; i++) {
        td[i].style.fontSize = size + "px";
    }
    
    // change the selected font size image
    switch(size) {
        case 12: 
            document.getElementById("norm_fs").src = "/new/images_structure/norm_fs_active.gif";
            document.getElementById("medium_fs").src = "/new/images_structure/medium_fs.gif";
            document.getElementById("large_fs").src = "/new/images_structure/large_fs.gif";
        break;
        
        case 14: 
            document.getElementById("norm_fs").src = "/new/images_structure/norm_fs.gif";
            document.getElementById("medium_fs").src = "/new/images_structure/medium_fs_active.gif";
            document.getElementById("large_fs").src = "/new/images_structure/large_fs.gif";
        break;
        
        case 16: 
            document.getElementById("norm_fs").src = "/new/images_structure/norm_fs.gif";
            document.getElementById("medium_fs").src = "/new/images_structure/medium_fs.gif";
            document.getElementById("large_fs").src = "/new/images_structure/large_fs_active.gif";
        break;
        
    }
        
    
}