.regenbogen {
    position: absolute;
    top: 40%;
   /*right:0;*/
    transform: translate(-20%, -50%);
    z-index: 1;

    vertical-align: middle;
    text-align: center;
    margin-top: 1.5rem;
}

.regenbogen ul {
    margin: 0;
    padding: 0;
    position: relative;
    width: 450px;
    height: 240px;
    overflow: hidden;
  
}

.regenbogen ul li {
    list-style: none;
    border-radius: 50%;
    border: 15px solid #000;
    position: absolute;
    top: 100%;
    left: 50%;
    border-bottom-color: transparent !important;
    border-left-color: transparent !important;
    
    animation: animate 20s infinite alternate;
    transform: translate(-50%, -50%);
}

.regenbogen ul li:nth-child(1) {
    width: 30px;
    height: 30px;

    border-color: #79c78b;
    
}

.regenbogen ul li:nth-child(2) {
    width: 50px;
    height:50px;
   
    border-color: #fbef8d;

}

.regenbogen ul li:nth-child(3) {
    width: 80px;
    height: 80px;
   
    border-color: #f9a694;

}

.regenbogen ul li:nth-child(4) {
    width: 110px;
    height: 110px;
  
    border-color: #ff8290;
    
}

.regenbogen ul li:nth-child(5) {
    width: 140px;
    height: 140px;
   
    border-color: #fcbbd3;
  
}

.regenbogen ul li:nth-child(6) {
    width: 170px;
    height: 170px;
 
    border-color: #be7b9a;
   
}

.regenbogen ul li:nth-child(7) {
    width: 200px;
    height: 200px;
   
    border-color: #4e85c6;

}

@keyframes animate {
    0% {
        transform: translate(-50%, -50%) rotate(-45deg);
    }

    20% {
        transform: translate(-50%, -50%) rotate(315deg);
    }

    100% {
        transform: translate(-50%, -50%) rotate(315deg);
    }
}