It's likely not being overridden, but being forced to be different by way of content. I see you are inspecting a table's th
cell, which will stretch to accommodate the content within it's column, even if it's width is defined in css.
<table>
<tr>
<th>30</th>
<th>30</th>
<th>30</th>
</tr>
<tr>
<td>30</td>
<td>More_than_30!</td>
<td>30</td>
</tr>
</table>
/* CSS */
th {width:30px; background:#CCC;}
td {width:30px; border:1px solid #CCC;}
Here, even though the th
and td
cells are given a width:30px;
that center row's cells' computed widths will be much larger due to the stretching of the data to accommodate the long, non-breaking value. In this case, there is no CSS rule overriding the 30px
.
See this fiddle: http://jsfiddle.net/rgthree/kYAG7/