每天一点点之css - 动画-一个圆绕着另一个圆动(绕着轨迹运动)

<div class="s">
    <div class="m">
        <div class="small small1">
            <div class="small-p small-p1"></div>
        </div>
    </div>
</div>

.s {
        width: 500px;
        height: 200px;
        border: 1px solid #ccc;
        position: relative;
        left: 50px;
        top: 50px;
        overflow: hidden;
        margin-bottom: 100px;
    }
    
    .small-p{
        width: 10px;
        height: 10px;
        border-radius: 5px;
        background: #ff0000;
        position: absolute;
        
    }
    .small-p1 {
        background: #dde3a2;
        top: -5px;
        left: 150px;
    }
    .small {
        position: relative;
        width: 300px;
        height: 300px;
        border-radius: 150px;
        left: 100px;
        top: -50px;
        animation: run 6s linear infinite;
        border: 1px solid #dde3a2;
    }
    .m {
        position: absolute;
    }
    @keyframes run{
        0%{
            transform: rotateZ(0deg);
        }
        100%{
            transform: rotateZ(360deg);
        }
    }