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HTML

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Insecure Resource

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CSS

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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

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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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Packages

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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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HTML 

              
                <h4>点击盒子触发</h4>
<div id="box"></div>
<script type="text/javascript">
  var box = document.querySelector("#box");
  //第一个问题 opacity
  //第二个问题 多个属性的写法 需要传入对象 move(box,{"width":300,"height":200},130,1500)
  box.onclick = function(){
    move(box,"opacity",100,1500);
    move(box,"left",300,1500);
  }

  function move(obj,attr,target,time){
    //如果没写默认值 默认就是0 不然在IE出问题
    if(attr=="opacity"){
      var curr = getStyle(obj,attr)*100;//把opacity的值化成整数 好计算
    }else {
      //有单位px parseInt去单位
      var curr = parseInt(getStyle(obj,attr))||0;
    }
    var end = target;
    var sTime = new Date();//开始时间T0
    //开始变换了
    var timer = setInterval(function(){
      var nTime = new Date();//当前时间Tt
      //St = (Tt-T0)/Time*(S-S0)+S0
      //(nTime-sTime)/time 比例最多为1
      var prop = (nTime-sTime)/time; 
      if(prop >=1){
        prop = 1;
        clearInterval(timer);
      }
      if(attr=="opacity"){
        var s = prop*(end-curr)+curr;
        //兼容IE 记得在样式中写上 否则会不生效 IE透明度是filter下的属性
        obj.style.filter = "alpha(opacity="+s+")";
        obj.style[attr] = s/100;
      }else{
        var s = prop*(end-curr)+curr;
        obj.style[attr] = s+"px";
      }

    },13);
  }
  function getStyle(obj,attr){
    return getComputedStyle(obj)[attr]?getComputedStyle(obj)[attr]:obj.currentStyle[attr];
  }


         </script>
!

CSS 

              
                #box {
  position: relative;
  width: 100px;
  height: 100px;
  background: red;
  opacity: 0.5;
  filter:alpha(opcity=20);/*兼容IE*/
}
!

JS
!
999px

Console