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Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

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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.

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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="m-demo">
  <div style="width:400px; height:200px;"></div>
  <div style="width:400px; height:200px;"></div>
  <div style="width:400px; height:200px;"></div>
  transition:max-height 0.8s;
  overflow: hidden;
/* 关键点在这里,指定一个很大的大于元素height:auto 时的高度的值,让元素过渡到一个达不到的height值,模拟了height:auto过渡的效果*/
              function getRandomColors(json){

var AdditionArr = [productAddition()];

function productColor(json){

for(var key in json){

var ele = json[key];

for(var i=0; i<ele.length; i++){

function isNowAdditionArr(){
var NowproductAddition = productAddition();

var NowAdditionArr = AdditionArr.every(function(item,index,array){
return item != NowproductAddition;



ele[i].style.backgroundColor = "rgb(" + AdditionArr[AdditionArr.length - 1].toString() + ")";




function productAddition(){
var Addition = [];

for(var j=0; j<2000; j++){
if(Addition.length == 3){
var rdm1 = Math.random().toFixed(1) * 10;
var rdm2 = Math.random().toFixed(1) * 10;
var rdm3 = Math.random().toFixed(1) * 10;
var Addit = Number(rdm1.toString() + rdm2.toString() + rdm3.toString());
if(Addit > 0 && Addit < 255){

return Addition;



a : document.getElementsByTagName("body")[0].getElementsByTagName("*")
}); /*生成随机颜色函数2,保证不会生成两个相同的颜色*/
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