example.haml

.toolbar
  %button
    touch me
.toolbar
  .button_group
    %button.left
      elo
    %button.inner
      in
    %button.inner
      in
    %button.right
      alo

osx_toolbar_button.sass

/* BUTTONS BUTTONS BUTTONS
   unfortunatelly I didn't invent these
   I allowed myself to copy the button styles
   for normal and active state from: http://general-metrics.com/Safari/
   I've added pressed state - but at this stage it's just a rough estimate on how it might look like :-)
 */

.toolbar
  button
    -webkit-box-shadow: rgba(225, 225, 225, 0.695312) 0px 1px 0px
    background-image: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#FDFDFD), to(darkGray))
    border: 1px solid #3D3D3D
    height: 20px
    //position: absolute
    -webkit-border-radius: 5px
      
  button:active
    background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0.7)), color-stop(0.2, rgba(0, 0, 0, 0.1)), color-stop(0.75, rgba(0, 0, 0, 0.1)), to(rgba(0, 0, 0, 0.3))), -webkit-gradient(linear, left top, right top, from(rgba(0, 0, 0, 0.4)), color-stop(0.2, rgba(0, 0, 0, 0.2)), color-stop(0.8, rgba(0, 0, 0, 0.2)), to(rgba(0, 0, 0, 0.5))), -webkit-gradient(linear, left top, left bottom, from(rgb(253, 253, 253)), to(rgb(169, 169, 169)))
    -webkit-user-drag: none
  button.pressed
    background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0.7)), color-stop(0.2, rgba(0, 0, 0, 0.1)), color-stop(0.75, rgba(0, 0, 0, 0.1)), to(rgba(0, 0, 0, 0.3))), -webkit-gradient(linear, left top, right top, from(rgba(0, 0, 0, 0.4)), color-stop(0.2, rgba(0, 0, 0, 0.2)), color-stop(0.8, rgba(0, 0, 0, 0.2)), to(rgba(0, 0, 0, 0.5))), -webkit-gradient(linear, left top, left bottom, from(rgb(253, 253, 253)), to(rgb(69, 69, 69)))

  .button_group
    button
      margin-left: -7px
    .right
      -webkit-border-top-left-radius: 0
      -webkit-border-bottom-left-radius: 0
    .left
      -webkit-border-top-right-radius: 0
      -webkit-border-bottom-right-radius: 0
    .inner
      -webkit-border-radius: 0px