• 怎么判断iphone上有没有安装某一app呢？比如，如果安装了就跳转到那个app,如果没有安装，就跳转到web.
  bundle ID:
  Every iOS app requires an "App ID" to work. This is a string that is set up during development, usually in the form of com.your-company.app-name
  . Please note that "App ID" and "Bundle ID" is generally used interchangeably.

display: 块级元素和inline元素

http://learnlayout.com/display.html
display is CSS's most important property for controlling layout. Every element has a default display value depending on what type of element it is. The default for most elements is usually block or inline. A block element is often called a block-level element. An inline element is always just called an inline element.

div is the standard block-level element. A block-level element starts on a new line and stretches out to the left and right as far as it can.
span is the standard inline element. An inline element can wrap some text inside a paragraph without disrupting the flow of that paragraph.

The a element is the most common inline element, since you use them for links.

none

二 重叠样式需要主要CSS样式解释

1、z-index 重叠顺序属性
2、position:relative和position:absolute设置对象属性为可定位（可重叠）
3、left right top bottom绝对定位具体位置设置

三 一个div在另一个div的底部

<div id="div1" style="border:1px solid red; width:500px; position:relative; height:500px;">
1111111
    <div id="div2" style="border:1px solid green; width:300px; height:200px; position:absolute; bottom:0px;">2222222222
    </div>
</div>

父元素position不能是static(默认值)
子元素potiosn需要是absolute

如何让父层DIV的滤镜效果不影响到子层DIV，就是说避免父层透明度的继承问题

1. 在IE9和大多数浏览器，使用rgba就能避免父级影响后代的不透明度问题：

background: rgba(0,0,0,0.8);//前面3个0为红绿蓝颜色值，最后一个为不透明度

2. 在父级中添加2个DIV，第一个设置opacity不透明度，第二个定位到第一个上面。因为2个DIV是同级，所以避免了opacity的影响。

四 两个class共用css:

.class1, .class2{
color: white;
}

五 margin

margin:10px 5px 15px 20px;
上外边距是 10px
右外边距是 5px
下外边距是 15px
左外边距是 20px

• span float:right 不work:

要先变成块display:block;定义宽高
然后再右对齐文本

• Radio

Screen Shot 2016-11-22 at 1.28.57 PM.png

• 字间距，行间距

word-spacing:50px; //字间距
line-height：50px; //行间距

• 加border边框

border-bottom: 1px solid #000;
border-width: 5px;

• 我是指 ion-email 这种图标，如果我要采用自定义的，怎么办？
  .ion-email::before { content: url('../img/newEmailIcon.png');}
  http://forum.ionicframework.com/t/add-custom-icons/559/10
  http://ionicframework.com/blog/building-ionicons/
  https://github.com/driftyco/ionicons#build-instructions

content: url('../images/selfProfile/icon-email.png');transform: scale(.5);

• ng-bind和{{}}的区别：

If you are not using ng-bind, instead something like this:

<div> Hello, {{user.name}}</div>

you might see the actual Hello, {{user.name}} for a second before user.name is resolved (before the data is loaded)
You could do something like this

<div> Hello, <span ng-bind="user.name"></span></div>

if that's an issue for you.

• How to center a button within a div?

button{ 
height:20px; 
width:100px; 
margin: -20px -50px; 
position:relative; 
top:50%;
 left:50%;}
or
div{ text-align:center;}

• 跟PJ学的，自己设计css,代码可读性：

#selfInfo-email-logo::before{   font-family: Ionicons;   font-style: normal;   font-weight: 400;   font-variant: normal;   text-transform: none;   text-rendering: auto;   line-height: 1;   -webkit-font-smoothing: antialiased;   -moz-osx-font-smoothing: grayscale;   content: url('../images/selfProfile/icon-email.png');   transform: scale(.5);}

• except one class:

table:not(.dojoxGrid) {color:red;}

• span width:
  span里面的字全部显示，不...的情况下，span的宽度限制：
  width: 94%;display: inline-flex;
• span 换行：
  white-space: normal;