added text about calc() inside tables

Author: howcom

css3-values/Overview.src.html

@@ -574,6 +574,13 @@ <h4>The 'calc', 'min' and 'max' functions</h4>
    return: the type of the left side
 </ol>
 
+<p>Given the complexities of 'width' and 'height' on table cells and
+  table elements, calc() expressions for 'width' and 'height' on table
+  columns, table column groups, table rows, table row groups, and
+  table cells in both auto and fixed layout tables are treated as if
+  'auto' had been specified.
+
+
 
 <h3>&lt;string&gt;</h3>