height 1px trick for % height

by techsin

HTML

<div class="a">
    <div class="b"></div>
</div>

CSS

*{padding: 0; margin: 0;}
body, html { height: 100%;}
div {
    border: 1px solid;

}

.a { min-height: 30%; height: 1px; }
.b { height: 50%; }

/* http://stackoverflow.com/questions/8468066/child-inside-parent-with-min-height-100-not-inheriting-height */