You may use display:table
/table-cell;
.a{_x000D_
position: absolute; _x000D_
left: 50px; _x000D_
top: 50px;_x000D_
display:table;_x000D_
}_x000D_
.b{_x000D_
text-align: left; _x000D_
display:table-cell;_x000D_
height: 56px;_x000D_
vertical-align: middle;_x000D_
background-color: pink;_x000D_
}_x000D_
.c {_x000D_
background-color: lightblue;_x000D_
}
_x000D_
<div class="a">_x000D_
<div class="b">_x000D_
<div class="c" >test</div>_x000D_
</div>_x000D_
</div>
_x000D_