@namespace url(http://www.w3.org/1999/xhtml);

@-moz-document domain("instructables.com") {

  #header,
  #sidebar,
  #actionLinks,
  #content,
  #footer,
  div[style^="margin-bottom"] {
    display: none !important;
  }

  body {
    background: none !important;
  }

  #you, #main_content, #container {
    width:600px !important;
  }

  div[style*="left: 600px;"] {
    display: none !important;
  }
}