JSFiddle - React, Tailwind, and code Playground

by Udi Talias

HTML

<div class="container">

  <div class="box">
    <div class="title">
      Drag Me!
    </div>
    <div class="content">
      <div>
        Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
      </div>
    </div>
  </div>
</div>

CSS

* {
  box-sizing: border-box;
}

body {
  margin:0;
}

.container {
  position: relative;
  width: 600px;
  height: 600px;
  background-color: yellow;
}

.box {
  position: absolute;
  width: 100px;
  height: 100px;
  background-color: pink;
  display: flex;
  flex-direction: column;
  top: 0;
  left: 0;
}

.box .title {
  background-color: black;
  color: white;
  padding: 5px;
}

.box .content {
  flex: 1;
  overflow: auto;
}

JavaScript

const title = document.querySelector(".title");
const box = document.querySelector(".box");

let isDragging = false;
let startX = 0;
let startY = 0;

title.addEventListener("mousedown", (e) => {
	document.addEventListener("mousemove", onMouseMove);
  document.addEventListener("mouseup", onMouseUp);
  
  const boxRect = box.getBoundingClientRect();
  startX = e.pageX - boxRect.left;
  startY = e.pageY - boxRect.top;
  
  isDragging = true;
});

function onMouseUp(e) {
	isDragging = false;
  document.removeEventListener("mousemove", onMouseMove);
  document.removeEventListener("mouseup", onMouseUp);
}

function onMouseMove(e) {
	const x = e.pageX - startX, y = e.pageY - startY;
  
	box.style.transform = `translate(${x}px, ${y}px)`;
}