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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.

If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.

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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.

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Using packages here is powered by Skypack, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ES6 import usage.

All packages are different, so refer to their docs for how they work.

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HTML 

              
                <div class="falls-2" id="falls_2"></div>
!

CSS 

              
                
/*  这里我们通过inline-block来布局 */
.falls-2  {
  position: relative;
}
/* 这里我们给元素设置宽度为25%，也就是按照四列来设置 */
.falls-2 .item{
  width: 25%;
  position: absolute;
}
/* 为了计算方便我们把所有的间距都在内部的元素中设置，
这样一来我们就不用再计算定位的时候在去额外计算内外间距的距离了 */
.falls-2 .item-inner{
  position: absolute;
  background-color: orange;
  top: 0;
  bottom: 10px;
  right: 10px;
  left: 10px;
  padding: 10px;
  font-size: 40px;
  color:white;
}
!

JS 

              
                
// 随机生成100条数据
var listArray = [];
for (var i = 0; i < 100; i++) {
  listArray.push(parseInt(Math.random() * (400 - 80 + 1) + 80, 10));
}
// 这里表示列数
var colLength = 4;
var falls_1 = document.getElementById('falls_2');
var colArray = [];
// 通过父级的宽度和设置的列数来计算出每一项的宽度
var itemW = falls_1.clientWidth/colLength;
// 循环列数，初始化第一次元素的初始位置
for(var x = 0; x<colLength;x++){
  colArray.push({t: 0, l: x*itemW});
}
// 循环数据
for(var x = 0; x<listArray.length; x++){
  // 取第一个初始化数据
  var curPosition = colArray[0];
  // 然后通过循环判断哪一个数据最低
  for(var y = 1; y<colArray.length; y++){
    if(curPosition.t > colArray[y].t){
      curPosition = colArray[y];
    }
  }
  // 创建元素，并且给元素设置位置信息和宽高等信息
  var item = document.createElement('div');
  var itemInner = document.createElement('div');
  item.setAttribute('class','item');
  itemInner.setAttribute('class','item-inner');
  item.style.height = listArray[x] + 'px';
  item.style.top = curPosition.t + 'px';
  item.style.left = curPosition.l + 'px';
  item.style.width = itemW + 'px';
  itemInner.innerText = x;
  item.appendChild(itemInner);
  falls_1.appendChild(item);
  // 然后更新初始化中的数据，使下次循环时记录
  curPosition.t = curPosition.t + listArray[x];
}
!
999px

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