Fitting iframe inside a div

I am trying to fit an iframe inside a div. My problem is that I can't seem to get it to nest to 100% of the width of the div, I need to specify pixel width of the iframe.

I would like the iframe to be "inside" the div so that if the div is resized by a smaller browser, the iframe gets resized too.

This is my code:

<div class="row-fluid">
   <div class="span9" id="standard">
      <div class="header-box">
         <p class="header">Bla Bla Header</p>
      </div>
      <div id="wrap">
         <iframe id="frame" src="https://docs.google.com/a/...." frameborder="0"></iframe>
      </div>
   </div>
   ...
</div>

And CSS:

#wrap { width: 1130px; height: 100%; padding: 0; overflow: hidden; position: relative; }

#frame {
   width: 100%;
   height: 100%;
   border: 1px solid black;
   position: relative;
}

#frame {
   zoom: 0.75;
   -moz-transform: scale(0.75);
   -moz-transform-origin: 0 0;
   -o-transform: scale(0.75);
   -o-transform-origin: 0 0;
   -webkit-transform: scale(0.75);
   -webkit-transform-origin: 0 0;
}

Below is what happenswhen the browser is resized.