.nav-bar {
    opacity: 0;
    top: 0;
    left: 0;
    width: 100%;
    background: #5F5F5F;
    background: rgb(0,0,0);
    background: linear-gradient(150deg, rgba(0,0,0,0.80) 0%, rgba(255,255,255,0) 15%),
                linear-gradient( 90deg, rgba(0,0,0,0.8) 0%, rgba(255,255,255,0) 8%);
  
   /* background: radial-gradient(circle at top -10px left 50px, rgba(0,0,0,1) 0%, rgba(255,255,255, 0) 10%),
    radial-gradient(circle at top -10px right 50px, rgba(0,0,0,1) 0%, rgba(255,255,255, 0) 10%);
   */
    background: rgb(0,0,0);
  
    text-align: center;
    height: 70px;
    display: flex;
    justify-content: center;
    align-content: center;
    transition: all .4s ease-in-out;
    z-index: 11;
}

.nav-bar.visible{
  opacity: 0.75;
}

#logo {
    z-index: 11;
    display: block;
    position: fixed;
    top: 20px;
    left: 30px;
  }
  .logo {
    height: 50px;
  }