/* ---------------------- */
/* - BOOTSTRAP 4 - SOUS-MENU - */
.dropdown-submenu {
  position: relative;
}
.dropdown-submenu .dropdown-menu {
  top: 0;
  left: 100%;
  margin-left: .1rem;
  margin-right: .1rem;
}
/* SPECIAL : ROTATION des flèches */
.dropdown-submenu a::after {
  transform: rotate(-90deg);
  position: absolute;
  right: 6px;
  top: .8em;
}

/* --------------------- */
/* SPECIAL : ROTATION des flèches */
/* Niveau 1 */
li .dropdown-toggle:after {
  transition: all 0.5s;
}
li.show > .dropdown-toggle:after {
  transform: rotate(180deg);
}
/* sous-Niveaux suivants */
li li.show > .dropdown-toggle:after {
  transform: rotate(90deg);
}
/* --------------------- */