Min-Left of DIV

I'm using something like this for one of my pages:

Code:

---

body {
  margin-right:10em;
}
div.links {
  position:absolute;
  right:0px;
  top:20px;
  width:9em;
}

---

Or something like that, and it keeps the menu aligned to the right without overlapping the body, but if the browser is resized to too small a size the menu over laps the body's text. Is there any attribute I can use to specify the min left that the DIV should be?