Код анимации падения

// HTML part
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS Shooting Stars Animation</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <section>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
    </section>
</body>
</html>

// CSS part
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    overflow: hidden;
}
section{
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: url(./bg0.jpg);
    background-position-x: center;
    background-size: cover;
    animation: animateBg 50s linear infinite;
}
@keyframes animateBg {
    0%,100%
    {
        transform:scale(1);
    }
    50%
    {
        transform:scale(1.2);
    }
}
span{
    position: absolute;
    top: 50%;
    left: 50%;
    width: 4px;
    height: 4px;
    background: #fff;
    border-radius: 50%;
    box-shadow: 0 0 0 4px rgba(255, 255, 255, 0.1), 0 0 0 8px rgba(255, 255, 255, 0.1), 0 0 20px rgba(255, 255, 255, 1)  ;
    animation:  animate 3s linear infinite;
}
span::before{
    content: '';
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 300px;
    height: 1px;
    background: linear-gradient(90deg, #fff, transparent);
}
@keyframes animate {
    0%
    {
        transform: rotate(315deg) translateX(0);
        opacity: 1;
    }
    70%
    {
        opacity: 1;

    }
    100%
    {
        transform: rotate(315deg) translateX(-1500px);
        opacity: 0;

    }
    
}
span:nth-child(1){
    top: 0;
    right: 0;
    left:initial;
    animation-delay:0 ;
    animation-duration: 1s;
}

span:nth-child(2){
    top: 0;
    right: 80px;
    left:initial;
    animation-delay:0.2s;
    animation-duration: 3s;
}

span:nth-child(3){
    top: 80px;
    right: 0px;
    left:initial;
    animation-delay:0.4s ;
    animation-duration: 2s;
}

span:nth-child(4){
    top: 0;
    right: 180px;
    left:initial;
    animation-delay:0.6s;
    animation-duration: 1.5s;
}

span:nth-child(5){
    top: 0;
    right: 400px;
    left:initial;
    animation-delay:0.8s;
    animation-duration: 2.5s;
}

span:nth-child(6){
    top: 0;
    right: 600px;
    left:initial;
    animation-delay:1s ;
    animation-duration: 3s;
}
span:nth-child(7 ){
    top: 300px;
    right: 0px;
    left:initial;
    animation-delay:1s ;
    animation-duration: 1.75s;
}

span:nth-child(8){
    top: 0px;
    right: 700px;
    left:initial;
    animation-delay:1.4s ;
    animation-duration: 1.25s;
}

span:nth-child(9){
    top: 0px;
    right: 1000px;
    left:initial;
    animation-delay:0.75s ;
    animation-duration: 2.25s;
}

span:nth-child(10){
    top: 0px;
    right: 1000px;
    left:initial;
    animation-delay:2.75s ;
    animation-duration: 2.25s;
}
akileus