SOURCE

console 命令行工具 X clear

                    
>
console
let startX
let startY
let mouseOffsetX
let mouseOffsetY

title.ondragstart = function (e) {
    const { left, top } = e.target.getBoundingClientRect()
    startX = left
    startY = top
    mouseStartX = e.pageX
    mouseStartY = e.pageY
    console.log(startX, startY)
}

title.ondragend = function (e) {
    const offsetX = e.pageX - mouseStartX
    const offsetY = e.pageY - mouseStartY
    const el = e.target

    el.style.left = `${startX + offsetX}px`
    el.style.top = `${startY + offsetY}px`
    console.log("drag end", offsetX, offsetY)
}
<body draggable="true">
	<h1 id="title" draggable="true">Hi friend, try edit me!</h1>
</body>
body {
    padding: 0;
    margin: 0;
    height: 100vh;
    background: #eee;
}

h1 {
    margin: 0;
    padding: 0;
    position: fixed;
    left: 0;
    top: 0;
    cursor: pointer;
    background: orange;
    /* transition: .3s; */
}