body { background-color:#4ECDC4; color:#fff;}
h1 { text-align:center;}
.wrapper { margin:150px auto 50px auto; max-width:960px;}
.container {
    height: 200px;
    position: relative;
    width: 100px;
    border: 1px solid red;
}
.inner {
    list-style: none;

    margin: 0;
    padding: 0;

    position: absolute;
    top: 0;
    left: 0;
    
}
.vertical .inner {
    width: 100%;
}

.inner li {
    padding: 10px 20px;
    position: relative;
}

.inner li + li{
    border-top: 1px solid rgba(0, 0, 0, 0.5);
}

.subInner {
    display: none;
    
    position: absolute;
    width: 200px;
    border: 1px solid rgba(0, 0, 0, 0.5); 
    padding: 10px 20px;
}

.vertical .subInner {
    left: 100px;
    top: 0;
}

li.is-active > .subInner {
    display: block;
}

.container.horizontal {
    height: 39px;
    width: 400px;

    margin-top: 200px;
}

.horizontal .inner {
    height: 100%;
    width: 704px;
}

.horizontal .inner:before,
.horizontal .inner:after {
    content: " ";
    display: table;
}
.horizontal .inner:after {
    clear: both;
}

.horizontal .inner li {
    display: inline-block;
    float: right;
}

.horizontal .subInner {
    left: 0;
    top: 39px;
}