function ShowSection(section)
{
    var K;
    var selected;
    
    // Start by hiding everything and returning all list items to normal.
    for (K = 0; K < sections.length; K++)
    {
        var each = sections[K];
        var listItem = 'F' + K;
        document.getElementById(each).className = 'hideFeature';
        document.getElementById(listItem).className = 'feature';
        if (each == section) selected = listItem;
    }
    
    // Highlight the selected section and its list item.
    document.getElementById(section).className = 'showFeature';
    document.getElementById(selected).className = 'selectedFeature';
}