* {
      margin: 0;
      padding: 0;
      list-style: none;
    }
    
    .slider {
      /*height: 340px;
      width: 790px;*/
    }
    
    .slider li {
      display: none;
    }

    .slider img{
      width: 100%;
    }

    .slider li:first-child {
      display: block;
    }