CSS3's border-radius property and border-colla

Question

Edit - Original Title: Is there an alternative way to achieve border-collapse:collapse in CSS (in order to have a collapsed, rounded corner table)?

Since it turns out that simply getting the table's borders to collapse does not solve the root problem, I have updated the title to better reflect the discussion.

I am trying to make a table with rounded corners using the CSS3 border-radius property. The table styles I'm using look something like this:

table {
    -moz-border-radius:10px;
    -webkit-border-radius:10px;
    border-radius:10px
}

Here's the problem. I also want to set the border-collapse:collapse property, and when that is set border-radius no longer works. Is there a CSS-based way I can get the same effect as border-collapse:collapse without actually using it?

Edits:

I've made a simple page to demonstrate the problem here (Firefox/Safari only).

It seems that a large part of the problem is that setting the table to have rounded corners does not affect the corners of the corner td elements. If the table was all one color, this wouldn't be a problem since I could just make the top and bottom td corners rounded for the first and last row respectively. However, I am using different background colors for the table to differentiate the headings and for striping, so the inner td elements would show their rounded corners as well.

Summary of proposed solutions:

Surrounding the table with another element with round corners doesn't work because the table's square corners "bleed through."

Specifying border width to 0 doesn't collapse the table.

Bottom td corners still square after setting cellspacing to zero.

Using JavaScript instead- works by avoiding the problem.

Possible solutions:

The tables are generated in PHP, so I could just apply a different class to each of the outer th/tds and style each corner separately. I'd rather not do this, since it's not very elegant and a bit of a pain to apply to multiple tables, so please keep suggestions coming.

Possible solution 2 is to use JavaScript (jQuery, specifically) to style the corners. This solution also works, but still not quite what I'm looking for (I know I'm picky). I have two reservations:

1. this is a very lightweight site, and I'd like to keep JavaScript to the barest minimum
2. part of the appeal that using border-radius has for me is graceful degradation and progressive enhancement. By using border-radius for all rounded corners, I hope to have a consistently rounded site in CSS3-capable browsers and a consistently square site in others (I'm looking at you, IE).

I know that trying to do this with CSS3 today may seem needless, but I have my reasons. I would also like to point out that this problem is a result of the w3c specification, not poor CSS3 support, so any solution will still be relevant and useful when CSS3 has more widespread support.

Answer 1

Solution with border-collapse:separate for table and display:inline-table for tbody and thead.

table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0px;
  background: transparent;   
}
table thead {
  display: inline-table;
  width: 100%;
  background: #fc0 url(../images/bg-heading.png) repeat-x 0% 0;
  -webkit-border-top-left-radius: 7px;
  -moz-border-radius-topleft: 7px;
  -webkit-border-top-right-radius: 7px;
  -moz-border-radius-topright: 7px;
    border-radius: 7px 7px 0px 0px;
  padding: 1px;
  padding-bottom: 0;
}

table tbody {
  border: 1px solid #ffffd;
  display: inline-table;
  width: 100%;
  border-top: none;        
}

Answer 2

The given answers only work when there are no borders around the table, which is very limiting!

I have a macro in SASS to do this, which fully supports external and internal borders, achieving the same styling as border-collapse: collapse without actually specifying it.

Tested in FF/IE8/Safari/Chrome.

Gives nice rounded borders in pure CSS in all browsers but IE8 (degrades gracefully) since IE8 doesn't support border-radius :(

Some older browsers may require vendor prefixes to work with border-radius, so feel free to add those prefixes to your code as necessary.

This answer is not the shortest - but it works.

.roundedTable {
  border-radius: 20px / 20px;
  border: 1px solid #333333;
  border-spacing: 0px;
}
.roundedTable th {
  padding: 4px;
  background: #ffcc11;
  border-left: 1px solid #333333;
}
.roundedTable th:first-child {
  border-left: none;
  border-top-left-radius: 20px;
}
.roundedTable th:last-child {
  border-top-right-radius: 20px;
}
.roundedTable tr td {
  border: 1px solid #333333;
  border-right: none;
  border-bottom: none;
  padding: 4px;
}
.roundedTable tr td:first-child {
  border-left: none;
}

To apply this style simply change your

<table>

tag to the following:

<table class="roundedTable">

and be sure to include the above CSS styles in your HTML.

Hope this helps.

Answer 3

I just wrote a crazy set of CSS for this that seems to work perfectly:

table {
  border-collapse: separate;
  border-spacing: 0;
  width: 100%;
}
table td,
table th {
  border-right: 1px solid #CCC;
  border-top: 1px solid #CCC;
  padding: 3px 5px;
  vertical-align: top;
}
table td:first-child,
table th:first-child {
  border-left: 1px solid #CCC;
}
table tr:last-child td,
table tr:last-child th {
  border-bottom: 1px solid #CCC;
}
table thead + tbody tr:first-child td {
  border-top: 0;
}
table thead td,
table th {
  background: #EDEDED;
}

/* complicated rounded table corners! */
table thead:first-child tr:last-child td:first-child {
  border-bottom-left-radius: 0;
}
table thead:first-child tr:last-child td:last-child {
  border-bottom-right-radius: 0;
}
table thead + tbody tr:first-child td:first-child {
  border-top-left-radius: 0;
}
table thead + tbody tr:first-child td:last-child {
  border-top-right-radius: 0;
}
table tr:first-child td:first-child,
table thead tr:first-child td:first-child {
  border-top-left-radius: 5px;
}
table tr:first-child td:last-child,
table thead tr:first-child td:last-child {
  border-top-right-radius: 5px;
}
table tr:last-child td:first-child,
table thead:last-child tr:last-child td:first-child {
  border-bottom-left-radius: 5px;
}
table tr:last-child td:last-child,
table thead:last-child tr:last-child td:last-child {
  border-bottom-right-radius: 5px;
}

/* end complicated rounded table corners !*/