.titre_presentation{
font-size:28px;
color:#5a5a5a;
}
.sous_titre_presentation{
font-size:24px;
color:#5a5a5a;
}
.content-presentation {
    margin-top: -140px;
    padding-bottom: 50px;
}
.content-presentation_ar {
    margin-top: -140px;
    padding-bottom: 50px;
}
@media screen and (max-width: 768px)  {
.content-presentation {
    margin-top: 0px;
    padding-bottom: 50px;
}
.titre_presentation{
font-size:18px;
}
.sous_titre_presentation{
font-size:16px;
}
}
@media screen and (max-width: 991px)  {
.content-presentation_ar {
    margin-top: 0px;
    padding-bottom: 50px;
}
}