.nav-submenu {position: absolute;
top: 100%;
right: -10px;
z-index: 999;
margin-top: 20px;
width: 290px;
max-height: 390px;        
overflow-y: auto;       
overflow-x: hidden;     
transform-origin: top;
border-radius: 8px;
background-color: rgb(255 255 255 / 1);
padding-top: 6px;
padding-bottom: 6px;
box-shadow: 0 4px 16px rgba(24,25,29,.18), 0 0 0 1px rgba(24,25,29,.05);
transition: all .2s cubic-bezier(.44, 0, .1, 1);
transform: perspective(1200px) rotateX(-20deg);
}