center-vertical

inline-block+padding-right+margin-right

by Three Tree

HTML

<div class="outer">
    <div class="inner"></div>
</div>

CSS

.outer {
    width: 100px;
    height: 100px;
    padding: 50px;
    overflow: auto;
    background: #ccc;
    white-space: nowrap;
}
.inner {
    display: inline-block; /*this does work*/
    width: 150px;
    height: 150px;
    margin: 50px;
    background: red;
}