Анимация дутого квадрата с помощью HTML/CSS

    <div class="container">
        <ul class="square">
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>
            <li></li>

        </ul>
    </div>

.square {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        list-style-type: none;
        height: 100%;
        overflow: hidden;
        padding-left: 0;
        margin-bottom: 0;
    }

    .square li {
        position: absolute;
        display: block;
        list-style: none;
        width: 20px;
        height: 20px;
        background: red;
        animation: moving 25s linear infinite;
        bottom: -150px;

    }

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


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

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

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

    .square li:nth-child(5) {
        left: 65%;
        width: 20px;
        height: 20px;
        animation-delay: 2s;
    }

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

    .square li:nth-child(7) {
        left: 35%;
        width: 100px;
        height: 100px;
        animation-delay: 10s;
        animation-duration: 25s;
    }

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

    .square li:nth-child(9) {
        left: 20%;
        width: 15px;
        height: 15px;
        animation-delay: 2s;
        animation-duration: 35s;
    }

    .square li:nth-child(10) {
        left: 10%;
        width: 10px;
        height: 10px;
        animation-delay: 0s;
        animation-duration: 15s;
    }

    @keyframes moving {

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

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

    }