/* динамическое меню */

function showSubMenu(day, dday) { 
    
    var menu = document.getElementById(day);
    var subMenu = document.getElementById(dday);
    
    subMenu.style.display = 'block';
    menu.style.background = '#555';
}

function hideSubMenu(day, dday) {
    
    var menu = document.getElementById(day);
    var subMenu = document.getElementById(dday);
  
    subMenu.style.display = 'none';
    menu.style.background = '#000';
}

/* навигация с помошью выпадающего селект-списка */

function changeLocation() {
    
    var navList = document.getElementById('navigator');
    var locationTitle = navList.value;
    
    switch(locationTitle){
        case '1':
        document.location = 'articles.html';
        break;
        
        case '2':
        document.location = 'tutorials.html';
        break;
    }
}