.listwrap {
border : 2px solid #000;
overflow:hidden;
}

.listwrap div {
min-height: 200px;
padding: 10px;
}
#one {
background-color: gray;
float:left;
margin-right:20px;
width:140px;
border-right:2px solid #000;
}
#two {
background-color: white;
overflow:hidden;
margin:10px;
border:2px dashed #ccc;
min-height:170px;
}

@media screen and (max-width: 800px) {
#one {
float: none;
margin-right:0;
width:auto;
border:0;
border-bottom:2px solid #000;
}
}