mycss

@import url('https://fonts.googleapis.com/css?family=Exo:400,700');
*{
    margin: 0px;
    padding: 0px;
}

body{
    font-family: 'Exo', sans-serif;
}

.context {
    width: 100%;
    position: absolute;
    top:50vh;
}

.context h1{
    text-align: center;
    color: #fff;
    font-size: 50px;
}

.area{
    width: 100%;
    height:100vh;
    -webkit-animation:bgcolorchange 20s infinite alternate;
}

.circles{
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.circles li{
    position: absolute;
    display: block;
    list-style: none;
    width: 20px;
    height: 20px;
    background: rgba(255, 255, 255, 0.2);
    animation: animate 5s linear infinite;
    bottom: -150px;
}

.circles li:nth-child(1){
    left: 25%;
    width: 80px;
    height: 80px;
    animation-delay: 0s;
}

.circles li:nth-child(2){
    left: 10%;
    width: 20px;
    height: 20px;
    animation-delay: 2s;
    animation-duration: 12s;
}

.circles li:nth-child(3){
    left: 70%;
    width: 20px;
    height: 20px;
    animation-delay: 4s;
}

.circles li:nth-child(4){
    left: 40%;
    width: 60px;
    height: 60px;
    animation-delay: 0s;
    animation-duration: 18s;
}

.circles li:nth-child(5){
    left: 65%;
    width: 20px;
    height: 20px;
    animation-delay: 0s;
}

.circles li:nth-child(6){
    left: 75%;
    width: 110px;
    height: 110px;
    animation-delay: 3s;
}

.circles li:nth-child(7){
    left: 35%;
    width: 150px;
    height: 150px;
    animation-delay: 7s;
}

.circles li:nth-child(8){
    left: 50%;
    width: 25px;
    height: 25px;
    animation-delay: 15s;
    animation-duration: 45s;
}

.circles li:nth-child(9){
    left: 20%;
    width: 45px;
    height: 45px;
    animation-delay: 2s;
    animation-duration: 35s;
}

.circles li:nth-child(10){
    left: 85%;
    width: 150px;
    height: 150px;
    animation-delay: 0s;
    animation-duration: 11s;
}

@keyframes animate {

    0%{
        transform: translateY(0) rotate(0deg);
        opacity: 1;
        border-radius: 0;
        background: #ffea00;
    }

    100%{
        transform: translateY(-1000px) rotate(720deg);
        opacity: 0;
        border-radius: 50%;
        background: #fdfa9b;
    }
}

@-webkit-keyframes bgcolorchange {
      0% {
      background-color: #7904a4;
      }
      10% {
        background-color: #8e44ad;
      }
      20% {
        background-color: #1abc9c;
      }
      30% {
        background-color: #d35400;
      }
      40% {
        background-color: blue;
      }
      50% {
        background-color: #34495e;
      }
      60% {
        background-color: blue;
      }
      70% {
        background-color: #2980b9;
      }
      80% {
        background-color: #0ef1b8;
      }
      90% {
        background-color: #2980b9;
      }
      100% {
        background-color: pink;
      }
    }