Spacing between thead and tbody

Answer 1

So box-shadow doesn't work well on the tr element... but it does work on a pseudo content element; sinsedrix put me on the right track and this is what I ended up with:

table {
    position: relative;
}

td,th {padding: .5em 1em;}

tr.even td { background-color: yellow; }
tr.odd td  { background-color: orange; }

thead th:first-child:before {
    content: "-";

    display: block;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    z-index: -1;

    box-shadow: 0 1px 10px #000000;
    padding: .75em 0;

    background-color: #ccc;
    color: #ccc;
}

thead th {
    padding-bottom: 2em;
}