Moving Two Step ------ training logical thinking

let timer = null;
function sport_02(obj,target){
clearInterval(timer);
timer = setInterval(()=>{
let speed = (target - obj.offsetLeft) / 8; //基数
speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed);
if(obj.offsetLeft === target){
clearInterval(timer);
}else{
obj.style.left = obj.offsetLeft + speed + ‘px’;
}
console.log(obj.offsetLeft,target,speed);
},30)
}