*{padding:0;margin:0;border:none;box-sizing:border-box}body{width:100%;height:100vh;display:flex;justify-content:center;align-items:center}.ball,.ball-2{background-color:#000;position:absolute;width:40px;height:40px;border-radius:50%}.ball-2{background-color:red!important}.btn{width:300px;height:300px;background-color:green;color:#ddd}