#top {
    position: relative;
   
  
    margin-top: 50px;
    margin-left: 15%;

    border: 0px ;
    width: 70%;
    height: 300px;
    overflow: hidden;
}


#bottom{
    position: relative;
   
  text-align: middle;
    margin-top: 0px;
    margin-left: 30%;

    border: 0px;
    width: 40%;
    height: 70px;
    overflow: hidden;
}

div.panel {
    position: absolute;
    height: 100%;
    width: 100%;
    display: none;
}

.next{
    position: absolute;
    bottom: 0px;
    width:100%;
        height:20%;
    text-align: center;
    vertical-align: middle;
    background-color: yellow;
    line-height: 1.7em;
     font-family: 'Ubuntu', sans-serif;
    font-weight: 400;
    font-size: 2.1em;
    text-decoration: none;
    border: none;
    color:grey;
}

.start{
    position: absolute;
    width:100%;
    text-align: center;
    vertical-align: middle;

    line-height: 1.7em;
     font-family: 'Ubuntu', sans-serif;
    font-weight: 400;
    font-size: 1.5em;
    text-decoration: none;
    border: none;
    color:grey;
}