Expand a div to fill the remaining width

Question

I want a two-column div layout, where each one can have variable width e.g.

Answer 1

You can try CSS Grid Layout.

dl {
  display: grid;
  grid-template-columns: max-content auto;
}

dt {
  grid-column: 1;
}

dd {
  grid-column: 2;
  margin: 0;
  background-color: #ccc;
}

  
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