Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URLs added here will be added as <link>s in order, and before the CSS in the editor. You can use the CSS from another Pen by using its URL and the proper URL extension.

+ add another resource

JavaScript

Babel includes JSX processing.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

Behavior

Auto Save

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.

HTML

              
                <div id="box"></div>
              
            
!

CSS

              
                #box {
  width: 200px;
  height: 200px;
  background-color: pink;
  position: relative;
}
              
            
!

JS

              
                function getStyleNum(el, style) {
  return parseInt(window.getComputedStyle(el)[style])
}
window.onload = function () {
  let box = document.getElementById("box")
  let dragging = false
  // 记录鼠标初始位置
  let mouseStartPos = { x: 0, y: 0 }
  // 记录元素初始位置
  let elStartPos = { x: 0, y: 0 }
  box.addEventListener("mousedown", function (e) {
    dragging = true
    box.style.position = "relative"
    // 获取鼠标点击的位置
    mouseStartPos.x = e.clientX
    mouseStartPos.y = e.clientY
    // 获取当前元素的位置
    elStartPos.x = getStyleNum(box, "left")
    elStartPos.y = getStyleNum(box, "top")
  })
  box.addEventListener("mousemove", function (e) {
    if (dragging) {
      // 计算鼠标在拖拽过程中的偏移量
      let offset = {
        x: e.clientX - mouseStartPos.x,
        y: e.clientY - mouseStartPos.y
      }
      // 将偏移量与元素开始时的位置相计算得出元素的实时位置
      box.style.left = elStartPos.x + offset.x + "px"
      box.style.top = elStartPos.y + offset.y + "px"
    }
  })
  // 鼠标移出元素或者抬起时停止拖拽
  box.addEventListener("mouseup", function (e) {
    dragging = false
  })
  box.addEventListener("mouseout", function (e) {
    dragging = false
  })
}
              
            
!
999px

Console