Code:
<div class="RightAsideBlock">
    <div class="BlockHeader">TEST HEADER</div>
    <div class="BlockContent ForTags">
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
        <div class="PopularTags"><a href="" >test</a></div>
    </div>
</div>
Css:
.RightAsideBlock {
    width: 100%;
    margin-bottom: 15px;
    box-shadow: 0.2em 0.2em 2px rgba(122,122,122,0.5);
}
.PopularTags {
    color: #acacac;
    background-color: #ededed;
    border: 0px;
    border: 1px solid #acacac;
    padding: 4px 5px;
    float: left;
    margin: 0 5px 5px 0;
    font-size: 12px;
}
In result we have:

Tell me please why div.ForTags not get height auto and divs div.PopularTags move beyond the block boundary div.ForTags ?
And how make right?
 
    