function toggle(id) {
    var elem = document.getElementById(id);
    
    if (elem.style.display == 'none' || elem.style.display == '') {
        elem.style.display = 'block'
    } else {
        elem.style.display = 'none'
    }
        
    var headerId = "header_" + id.substring(5);
    
    var header = document.getElementById(headerId);
    
    if (elem.style.display == 'block') {
        header.style.backgroundColor = '#ffffff';
    } else {
        header.style.backgroundColor = '#eef3f3';
    }
}