CSS table layout: why does table-row not accept a margin?

Answer 1

If you want a specific margin e.g. 20px, you can put the table inside a div.

    

      

        
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So the #tableDiv has a margin of 20px but the table itself has a width of 100%, forcing the table to be the full width except for the margin on either sides.

#tableDiv {
  margin: 20px;
}

table {
  width: 100%;
}