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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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About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient. For instance, CoffeeScript can help prevent easy-to-make mistakes and offer a cleaner syntax and Babel can bring ECMAScript 6 features to browsers that only support ECMAScript 5.

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You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

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HTML

            
              <p>不设置flex-basis，占据宽度为项目宽度</p>
<div class="wrap">
	<div class="item">宽度200</div>
	<div class="item">宽度200</div>
	<div class="item">宽度200</div>
</div>
<p>设置flex-basis，占据宽度为flex-basis</p>
<div class="wrap">
	<div class="item setFlexBasis">宽度100</div>
	<div class="item setFlexBasis">宽度100</div>
	<div class="item setFlexBasis">宽度100</div>
</div>
<p>设置flex-basis，受限于min-width和max-width</p>
<div class="wrap">
	<div class="item setFlexBasis minWidth">宽度300</div>
	<div class="item setFlexBasis maxWidth">宽度50</div>
	<div class="item setFlexBasis">宽度100</div>
</div>
!

CSS

            
              .wrap
	display flex
	border 4px solid #000
	width 800px
	.item
		width 200px
		height 200px
		&:nth-child(1)
			background #eee
		&:nth-child(2)
			background red
		&:nth-child(3)
			background yellow
		&.setFlexBasis
			flex-basis 100px
			&.minWidth
				min-width 300px
			&.maxWidth
				max-width 50px
!

JS
!
999px
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