jquery.omniwindow.css

/* Default class for an overlay */
.ow-overlay {
  position: fixed;
  z-index: 10;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;

  background: #424242;
  opacity: 0.8;
}

/* Default class for both hidden overlay and modal window */
.ow-closed {
  display: none;
}

/* Default class for modal window */
.modal {
  position: fixed;
  z-index: 20;
  left: 50%;
  top: 50px;
  width: 300px;
  height: 300px;

  background-color: #fff;
}