landlord, I recommend you to use vw layout

.foot {
  margin-top: 1rem;
  .foot-menu {
      display: flex;
      .menu-item {
         width: 25vw;
         height: 25vw;
         @extend: .box-shadow;
      }
     
      .menu-item2 {
         width: 50vw;
         height: 50vw;
         @extend: .box-shadow;
      }   
  }
}

the division according to the demand is better than the calculation of the subject himself.