body,
html {
    width: 100%;
    height: 100%;
    padding: 0;
}

body.duel {
    background-color: rgb(4,3,6);
    background-image: url('https://straybasilisk.com/wp-content/uploads/2017/10/campfire_light.gif');
    background-size: 100% auto;
    background-repeat: no-repeat;
    background-position: left bottom;
    position:fixed;
}

.duelDiv {
  width: 950px;
  height: 256px;
  position: absolute;
  top: 40%;
  left: 50%;
  margin-left: -475px;
  margin-top: -128px;
}

.duelInfoText {
    font-size:2em;
    font-family:tahoma, verdana, arial, sans-serif;
    color: rgb(200, 200, 200);
}