#centerbox {
  z-index: 10;
}

.w100 {
  box-sizing: border-box;
}

.w100 {
  z-index: 5;
  position: absolute;
  bottom: 0;
  left: 0;

  width: 100%;
  max-width: 301px;
  padding-right: 1px;
  margin: 10px;
}

.banner {
    max-height: 180px;
    max-width: 300px;
}