.ball {
  z-index: -1;
  position: absolute;
  border-radius: 100%;
  opacity: 0.7;
}

@keyframes animate {
  0%{
      transform: translateY(0) rotate(0deg);
      opacity: 1;
      border-radius: 0;
  }
  100%{
      transform: translateY(-1000px) rotate(720deg);
      opacity: 0;
      border-radius: 50%;
  }
}

.background {
  z-index: -2;
  position: fixed;
  width: 100vw;
  height: 100vh;
  top: 0;
  left: 0;
  margin: 0;
  padding: 0;
  background: #94e3fe;
  overflow: hidden;
}
.background li {
  position: absolute;
  display: block;
  list-style: none;
  width: 20px;
  height: 20px;
  background: rgba(255, 255, 255, 0.4);
  animation: animate 19s linear infinite;
}




.background li:nth-child(0) img {
  left: 24%;
  width: 131px;
  height: 131px;
  bottom: -131px;
  animation-delay: 1s;
}
.background li:nth-child(1) img{
  left: 36%;
  width: 122px;
  height: 122px;
  bottom: -122px;
  animation-delay: 1s;
}
.background li:nth-child(2) {
  left: 35%;
  width: 178px;
  height: 178px;
  bottom: -178px;
  animation-delay: 10s;
}
.background li:nth-child(3) {
  left: 68%;
  width: 181px;
  height: 181px;
  bottom: -181px;
  animation-delay: 15s;
}
.background li:nth-child(4) {
  left: 88%;
  width: 183px;
  height: 183px;
  bottom: -183px;
  animation-delay: 18s;
}
.background li:nth-child(5) {
  left: 30%;
  width: 188px;
  height: 188px;
  bottom: -188px;
  animation-delay: 20s;
}
.background li:nth-child(6) {
  left: 39%;
  width: 101px;
  height: 101px;
  bottom: -101px;
  animation-delay: 29s;
}
.background li:nth-child(7) {
  left: 15%;
  width: 145px;
  height: 145px;
  bottom: -145px;
  animation-delay: 21s;
}
.background li:nth-child(8) {
  left: 82%;
  width: 176px;
  height: 176px;
  bottom: -176px;
  animation-delay: 24s;
}
.background li:nth-child(9) {
  left: 70%;
  width: 158px;
  height: 158px;
  bottom: -158px;
  animation-delay: 38s;
}