body {
  margin: 0px;
  padding: 0px;
  background-color: #000000;
  }
  
#container {
  width: 600px;
  height: 500px;
  padding-top: 80px;
  margin: 0 auto;
  }
.bar {
  width: 20px;
  height: 50px;
  margin: 0 12px;
  border-radius: 50px;
  float: left;
  }
  
  
.bar:nth-child(1) {
  background-color: #ffffff;
  animation: up 1s infinite ease-in-out;
  }

.bar:nth-child(2) {
  background-color: #ffffff;
  animation: down 1.1s infinite ease-in-out;
  }

.bar:nth-child(3) {
  background-color: #ffffff;
  animation: up 1.2s infinite ease-in-out;
  }

.bar:nth-child(4) {
  background-color: #ffffff;
  animation: down 1.3s infinite ease-in-out
  }

.bar:nth-child(5) {
  background-color: #ffffff;
  animation:up 1.4s infinite ease-in-out;
  }

.bar:nth-child(6) {
  background-color: #ffffff;
  animation:up 1.5s infinite ease-in-out;
  }
  
.bar:nth-child(7) {
  background-color: #ffffff;
  animation:up 1.6s infinite ease-in-out;
  }
  
.bar:nth-child(8) {
  background-color: #ffffff;
  animation:up 1.7s infinite ease-in-out;
  }
  
.bar:nth-child(9) {
  background-color: #ffffff;
  animation:up 1.8s infinite ease-in-out;
  }
  
.bar:nth-child(10) {
  background-color: #ffffff;
  animation:up 1.9s infinite ease-in-out;
  }
  
.bar:nth-child(11) {
  background-color: #ffffff;
  animation:up 1.10s infinite ease-in-out;
  }
  
.bar:nth-child(12) {
  background-color: #ffffff;
  animation:up 1.11s infinite ease-in-out;

  }
  
  
@keyframes up {
  0% { transform: translateY(-75px); background-color: #000000;}
  25% { background-color: #ffffff;}
  50% { transform: translateY(75px); background-color: #000000}
  75% { background-color: #ffffff;}
  100% { transform: translateY(-75px); background-color: #000000}
  }

@keyframes down {
  0% { transform: translateY(75px); background-color: #000000}
  25% { background-color: #ffffff;}
  50% { transform: translateY(-75px); background-color: #000000}
  75% { background-color: #ffffff;}
  100% { transform: translateY(75px); background-color: #000000}
  }