CSS validation Issue

If my website had as many parse errors as the validator called out it would be unreadable.  Does the current validator understand nested CSS?

I can’t figure out what’s wrong with this (one example):

 #menud {
  width: 80%;
  margin: 0px 10% 4px 10%;
  text-align: left;
  font-size: .75vw;
  background-color: transparent;
  border: none;
  .menudformd {
   display: inline-block;  
   margin: 0px 4px 4px 0px;
   border: none;
   input[type=submit] {  
    background-color: transparent;
    font-size: .75vw;
    color: ivory;
    border: none;
    &:hover {
     color: red;
     cursor: pointer;
    }
   }
  } /* menuformd */ 
 } /* menud */


Bruce Quimby
bquimby1@icloud.com