pierluigi Hi. Please try use this code in css:
@media only screen and (max-width:767px) {
#bd h1.logo {
margin-top: 0;
margin-left: 0 !important;
background-size: 100% auto;
width: 100%;
}
h1.logo a {
background-size: 100% auto;
}
}
to change the Navigation word You will need to do that in template's language file in joomlas /language folder.
For the red first menu level please try with this added to css:
@media only screen and (max-width:767px) {
div.ja-megamenu ul.level0 li > a { color: red; }
}