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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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Adding Classes

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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-.

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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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HTML 

              
                <h4>点击盒子触发</h4>
<div id="box"></div>
!

CSS 

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

JS 

              
                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,{
    "width":200,
    "height":200,
    "left":100,
    "top":100,
    "opacity":100
  },1500,function(){
    move(box,{
      "width":100,
      "height":100,
      "left":0,
      "top":0
    },1000,function(){
      this.style.background = "green";
    });
  });
}

function move(obj,json,time,callback){
  //一般定时器结束后最好清除
  clearInterval(obj.timer);
  var curr = {};
  var end = {};
  //通过for in 在上车前把所有东西装到包里
  for(var attr in json){
    if(attr == "opacity"){//opacity特殊东西特殊对待
      curr[attr] = getStyle(obj,attr)*100;//化为整数好计算
    }else{
      curr[attr] = parseInt(getStyle(obj,attr))||0;
    }
    end[attr] = json[attr];

  }


  //如果没写默认值 默认就是0 不然在IE出问题
  //var curr = parseInt(getStyle(obj,attr))||0;
  //var end = target;
  var sTime = new Date();//开始时间T0
  //开始变换了
  obj.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(obj.timer);
      callback && callback.call(obj);
    }
    for(var attr in json){
      if(attr == "opacity"){
        var s = prop*(end[attr]-curr[attr])+curr[attr];
        obj.style[attr] = s/100;
        obj.style.filter = "alpha(opacity="+s+")";
      }else{
        var s = prop*(end[attr]-curr[attr])+curr[attr];
        obj.style[attr] = s+"px";
      }

    }


  },13);
}
function getStyle(obj,attr){
  return getComputedStyle(obj)[attr]?getComputedStyle(obj)[attr]:obj.currentStyle[attr];
}
!
999px

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