Border-top from tbody and border-bottom from thead don't work at the same time?

Question

I have a very basic table:

<table id="ttable5" class="table-default">
        <thead>
        <tr>
            <th>Nombre</th>
                <th class="sort-date">Provincia</th>
            <th class="sort-digit">Municipio</th>
        </tr>
    </thead>
    <tbody>
        <tr>

            <td class="tablaprim">1VESTIBULUM TORTOR NISL </td>
            <td>Sevilla</td>
            <td>Castilleja de la Cuesta</td>
        </tr>
        <tr>

            <td class="tablaprim">4VESTIBULUM TORTOR NISL </td>
            <td>Sevilla</td>
            <td>Castilleja de la Cuesta</td>
        </tr>
    </tbody>
</table>

I need to have this:

------------
head
------------1px border #fff
------------3px border #gray
body
------------

I can only get to show one of the borders, never two at the same time. It's not really important but I'm curious about what is causing this issue.

My css:

thead{border-bottom: 1px solid #fff;}
tbody{border-top: 3px solid #4d4d4d;}

EDIT:

Since it seems like the border-collapse might be the issue but I can't make it work I've set up this sandbox:

http://jsfiddle.net/bRVEu/

There you can see there's only a grey border, there should be a 1px white border right on top of it

Answer 1

In order for this to work, you need to

a) use both border-collapse and border-spacing

b) set the borders on the most interior elements of the table

c) you must set border-collapse and border-spacing on the table so it inherits

so

table {
  background: pink; 
  border: 0; 
  border-collapse: separate; 
  border-spacing: 0 5px;
}

thead tr th {
  border-bottom: 1px solid red; 
  border-collapse: separate; 
  border-spacing: 5px 5px;
} 

tbody tr#first td {
  border-top: 3px solid #4d4d4d; 
  border-collapse: separate;
  border-spacing: 5px 5px;
}

I changed some of the colors to make it easier to see.

http://jsfiddle.net/jasongennaro/Pf7My/1/

Answer 2

Check the value of border-collapse. If it's collapse, then the browser will merge adjacent borders.