nav ul li {
    padding: 10px;
}
.sub-menu-1{
    display: none;
    width: 250px;
}
nav ul li:hover .sub-menu-1{
    display: block;
    position: absolute;
    background-color: #9499a5;
    margin-top: 20px;
}
nav ul li:hover .sub-menu-1 ul{
    display: block;
}
nav ul li:hover .sub-menu-1 ul li{
    width: 250px;
    text-align: left;
    transition: 0.7s;
}
nav ul li:hover .sub-menu-1 ul li:hover{
    background-color: #263a4e;
}
.sub-menu-2{
    display: none;
    width: 350px;
    max-height: calc(100vh - 250px);
    overflow-y: auto;
}
.hover-sub:hover .sub-menu-2{
    display: block;
    position: absolute;
    width: 350px;
    margin-top: -35px;
    margin-left: 240px;
    background-color: #9499a5;
}
nav ul li:hover .sub-menu-2 ul li{
    width: 350px;
    text-align: left;
    transition: 0.7s;
}

@media (max-width: 768px) {
    .sub-menu-1 {
      position: fixed;
      top: 250px;
      left: 0;
      width: 35%;
      height: 20%;
      background-color: #fff;
      z-index: 1000;
      display: none;
    }
    .sub-menu-1 ul {
      list-style: none;
      padding: 0;
      margin: 0;
      text-align: center;
    }
    .sub-menu-1 ul li {
      padding: 10px;
    }
    .sub-menu-2{
        display: none;
        width: 250px;
        max-height: calc(100vh - 250px);
        overflow-y: auto;
    }
    .hover-sub:hover .sub-menu-2{
        display: block;
        position: absolute;
        width: 300px;
        margin-top: -35px;
        margin-left: 120px;
        background-color: #9499a5;
    }
    nav ul li:hover .sub-menu-2 ul li{
        width: 350px;
        text-align: left;
        transition: 0.7s;
    }
}

@media (max-width: 768px) {
    .sub-menu-1 {
      display: none;
    }
    .sub-menu-2{
        display: none;
        width: 250px;
        max-height: calc(100vh - 250px);
        overflow-y: auto;
    }
    .hover-sub:hover .sub-menu-2{
        display: block;
        position: absolute;
        width: 300px;
        margin-top: -35px;
        margin-left: 120px;
        background-color: #9499a5;
    }
    nav ul li:hover .sub-menu-2 ul li{
        width: 350px;
        text-align: left;
        transition: 0.7s;
    }
}