.nav_menu{
    margin-top:5rem;
    /* position:absolute; */
    position: fixed;
    font-weight: 100;

    padding-left:5vw;
    font-family: Helvetica , sans-serif;
    font-weight: 100;
    z-index: 0;
}

.fixed_nav_menu{
    position: fixed;
    z-index: 0;
    margin-top:5rem;
    padding-left:5vw;


}

.menu_item{
    all:unset;
    font-weight: 100;

    transition: .5s;
    color:#007c00;
    letter-spacing: -.1em;
    font-size: 4vh;
    text-align: start;
    position: relative;
    z-index: 0;
}

.expanded{
    letter-spacing: 0.4em;
}