body {
    margin: 0;
    padding: 0;

  }
  
  header {
    position: absolute;
    top: 0;
    left: 0;
    padding: 0 100px;
    background: #36AE7C;
    width: 100%;
    box-sizing: border-box;
  }
  
  header .logo {
    color: #fff;
    height: 50px;
    line-height: 50px;
    font-size: 30px;
    float: left;
    font-weight: bold;
  }
  header nav {
    float: right;
  }
  
  header nav ul {
    margin: 0;
    padding: 0;
    display: flex;
  }
  
  /* !  Drop down */
  header nav ul li {
    list-style: none;
    position: relative;
  }
  
  header nav ul li.sub-menu:before {
    content: "\25BC";
    font-family: FontAwesome;
    position: absolute;
    line-height: 50px;
    color: #fff;
    right: 5px;
    font-size: 14px;
  }
  
  header nav ul li.active.sub-menu:before {
    content: "\25B2";
  }
  
  header nav ul li ul {
    position: absolute;
    left: 0;
    background: #3abf87;
    display: none;
  }
  header nav ul li.active ul {
    display: block;
  }
  header nav ul li ul li {
    display: block;
    width: 200px;
  }
  /* ! */
  header nav ul li a {
    height: 50px;
    line-height: 50px;
    padding: 0 20px;
    color: #fff;
    text-decoration: none;
    display: block;
  }
  
  header nav ul li a.active,
  header nav ul li a:hover {
    color: #fff;
    background: #3d3e3e;
  }
  
  .menu-toggle {
    color: #fff;
    float: right;
    line-height: 50px;
    font-size: 30px;
    cursor: pointer;
    display: none;
  }
  
  @media (max-width: 991px) {
    header {
      padding: 0 20px;
    }
    .menu-toggle {
      display: block;
    }
  
    header nav {
      /* display: none; */
      position: absolute;
      width: 100%;
      height: calc(100vh - 50px);
      background: #333;
      top: 50px;
      left: -100%;
      transition: 0.5s;
    }
  
    header nav.active {
      left: 0;
    }
  
    header nav ul {
      display: block;
      text-align: center;
    }
  
    header nav ul li a {
      border-bottom: 1px solid rgba(0, 0, 0, 0.2);
    }
    /* ! Drop down */
    header nav ul li.active ul {
      position: relative;
      background: #003e6f;
    }
  
    header nav ul li ul li {
      width: 100%;
    }
    /* ! */
  }