Question

I tried to set height: 100%; in the label, but it didn’t work. Why not?

.field label {
    color:#3E3E3E;
    font-weight:bold;
    width:80px;
    display:block;
    float:left;
    margin-top:5px;
    margin-left:3px;
    height:100%; /* <-- doesn't work */
}
.field {
    display:block;
    margin-bottom:9px;
    background:none;
    border:none;
}

<div class="field large">
    <label>Textarea</label>
    <textarea></textarea>
</div>

Answer 1

You have height set to 100% but 100% of what? It’s always the parent of that element so what is the parent’s height set to? If it’s not set to anything then the browser has nothing to reference.