body {
 margin: 0;
 height: 100vh;
 background-color: #333;
}

.container {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
}

.text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  text-transform: uppercase;
  font-size: 45px;
  border-top: 5px solid white;
  border-bottom: 5px solid white;
}

.square{
  position: absolute;
  bottom: -100px;
  background-color: #f2f2f2;
  animation: boxes 10s infinite ease-in-out;
}

.square:nth-child(1) {
  width: 75px;
  height: 75px;
  left: 7%;
}

.square:nth-child(2) {
  width: 65px;
  height: 65px;
  left: 15%;
  animation-delay: 4s;
}

.square:nth-child(3) {
  width: 82px;
  height: 82px;
  left: 45%;
  animation-delay: 8s;
}

.square:nth-child(4) {
  width: 70px;
  height: 70px;
  left: 55%;
  animation-delay: 2s;
}

.square:nth-child(5) {
  width: 60px;
  height: 60px;
  left: 27%;
  animation-delay: 6s;
}

.square:nth-child(6) {
  width: 55px;
  height: 55px;
  left: 60%;
  animation-delay: 4s;
}

.square:nth-child(7) {
  width: 90px;
  height: 90px;
  left: 85%;
  animation-delay: 9s;
}

.square:nth-child(8) {
  width: 70px;
  height: 70px;
  left: 75%;
  animation-delay: 4s;
}

.square:nth-child(9) {
  width: 45px;
  height: 45px;
  left: 10%;
  animation-delay: 7s;
}

.square:nth-child(10) {
  width: 55px;
  height: 55px;
  left: 60%;
  animation-delay: 7s;
}

@keyframes boxes {
  0% { bottom: -100px }

  100% { bottom: 100%;
  transform: rotate(180deg);
  opacity: 0; }
}