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

.background {
    position: fixed;
    width: 100vw;
    height: 100vh;
    top: 0;
    left: 0;
    margin: 0;
    padding: 0;
    overflow: hidden;
}

.background li {
    position: absolute;
    display: block;
    list-style: none;
    width: 20px;
    height: 20px;
    background: rgba(255, 255, 255, 0.2);
    animation: particleAnim 12s linear infinite;
}

.background li:nth-child(0) {
    left: 84%;
    width: 258px;
    height: 258px;
    bottom: -258px;
    animation-delay: 1s;
}
.background li:nth-child(1) {
    left: 36%;
    width: 281px;
    height: 281px;
    bottom: -281px;
    animation-delay: 2s;
}
.background li:nth-child(2) {
    left: 28%;
    width: 159px;
    height: 159px;
    bottom: -159px;
    animation-delay: 7s;
}
.background li:nth-child(3) {
    left: 19%;
    width: 160px;
    height: 160px;
    bottom: -160px;
    animation-delay: 5s;
}
.background li:nth-child(4) {
    left: 2%;
    width: 280px;
    height: 280px;
    bottom: -280px;
    animation-delay: 17s;
}
.background li:nth-child(5) {
    left: 25%;
    width: 236px;
    height: 236px;
    bottom: -236px;
    animation-delay: 19s;
}
.background li:nth-child(6) {
    left: 52%;
    width: 183px;
    height: 183px;
    bottom: -183px;
    animation-delay: 12s;
}
.background li:nth-child(7) {
    left: 55%;
    width: 114px;
    height: 114px;
    bottom: -114px;
    animation-delay: 3s;
}
.background li:nth-child(8) {
    left: 65%;
    width: 213px;
    height: 213px;
    bottom: -213px;
    animation-delay: 18s;
}
.background li:nth-child(9) {
    left: 83%;
    width: 280px;
    height: 280px;
    bottom: -280px;
    animation-delay: 31s;
}
.background li:nth-child(10) {
    left: 19%;
    width: 144px;
    height: 144px;
    bottom: -144px;
    animation-delay: 2s;
}
.background li:nth-child(11) {
    left: 13%;
    width: 200px;
    height: 200px;
    bottom: -200px;
    animation-delay: 33s;
}
.background li:nth-child(12) {
    left: 57%;
    width: 294px;
    height: 294px;
    bottom: -294px;
    animation-delay: 54s;
}
.background li:nth-child(13) {
    left: 57%;
    width: 100px;
    height: 100px;
    bottom: -100px;
    animation-delay: 57s;
}
.background li:nth-child(14) {
    left: 61%;
    width: 180px;
    height: 180px;
    bottom: -180px;
    animation-delay: 28s;
}
.background li:nth-child(15) {
    left: 21%;
    width: 277px;
    height: 277px;
    bottom: -277px;
    animation-delay: 62s;
}
.background li:nth-child(16) {
    left: 43%;
    width: 154px;
    height: 154px;
    bottom: -154px;
    animation-delay: 13s;
}
.background li:nth-child(17) {
    left: 29%;
    width: 230px;
    height: 230px;
    bottom: -230px;
    animation-delay: 44s;
}
.background li:nth-child(18) {
    left: 67%;
    width: 183px;
    height: 183px;
    bottom: -183px;
    animation-delay: 32s;
}
.background li:nth-child(19) {
    left: 81%;
    width: 174px;
    height: 174px;
    bottom: -174px;
    animation-delay: 65s;
}
.background li:nth-child(20) {
    left: 88%;
    width: 246px;
    height: 246px;
    bottom: -246px;
    animation-delay: 15s;
}
.background li:nth-child(21) {
    left: 7%;
    width: 100px;
    height: 100px;
    bottom: -100px;
    animation-delay: 54s;
}
.background li:nth-child(22) {
    left: 19%;
    width: 114px;
    height: 114px;
    bottom: -114px;
    animation-delay: 106s;
}
.background li:nth-child(23) {
    left: 85%;
    width: 146px;
    height: 146px;
    bottom: -146px;
    animation-delay: 74s;
}
.background li:nth-child(24) {
    left: 44%;
    width: 179px;
    height: 179px;
    bottom: -179px;
    animation-delay: 5s;
}

/* Mobile */

@media screen and (max-width: 736px) {
    
    .background li:nth-child(0) {
        left: 22%;
        width: 64px;
        height: 64px;
        bottom: -64px;
        animation-delay: 1s;
    }
    .background li:nth-child(1) {
        left: 65%;
        width: 61px;
        height: 61px;
        bottom: -61px;
        animation-delay: 2s;
    }
    .background li:nth-child(2) {
        left: 47%;
        width: 64px;
        height: 64px;
        bottom: -64px;
        animation-delay: 4s;
    }
    .background li:nth-child(3) {
        left: 43%;
        width: 85px;
        height: 85px;
        bottom: -85px;
        animation-delay: 10s;
    }
    .background li:nth-child(4) {
        left: 18%;
        width: 66px;
        height: 66px;
        bottom: -66px;
        animation-delay: 2s;
    }
    .background li:nth-child(5) {
        left: 41%;
        width: 34px;
        height: 34px;
        bottom: -34px;
        animation-delay: 12s;
    }
    .background li:nth-child(6) {
        left: 66%;
        width: 65px;
        height: 65px;
        bottom: -65px;
        animation-delay: 6s;
    }
    .background li:nth-child(7) {
        left: 67%;
        width: 36px;
        height: 36px;
        bottom: -36px;
        animation-delay: 7s;
    }
    .background li:nth-child(8) {
        left: 20%;
        width: 38px;
        height: 38px;
        bottom: -38px;
        animation-delay: 35s;
    }
    }