body, html {
    background-color: black;
   height: 100%;
   margin: 0;
   width: 100vw;
   overflow-y: overlay;
   overflow-x: hidden;
}

.bg {
    background-color: black;
    height: 100%;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
  }
.white {
    background-color: white;
    height: 100%;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
  }
.growth {
    background-image: url("../img/gif/growth.gif");
    height: 100%;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
}

.center {
  display: block;
  margin-left: auto;
  margin-right: auto;
  height: 100%;
  opacity: 1;
}