#buttons #top    { top: 0;   }
#buttons #left   { top: 50;  }
#buttons #right  { top: 100; }
#buttons #bottom { top: 150; }

sidebar {
  background: yellow;
}

sidebar button {
  width:      100%;
  background: clear;
}

sidebar #b1 { top: 50;  }
sidebar #b2 { top: 100; }
sidebar #b3 { top: 150; }
sidebar #b4 { top: 200; }