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padding-bottom--lg"><div class="row"><div class="col docItemCol_DM6M"><div class="docItemContainer_vinB"><article><nav class="theme-doc-breadcrumbs breadcrumbsContainer_Xlws" aria-label="breadcrumbs"><ul class="breadcrumbs" itemscope="" itemtype="https://schema.org/BreadcrumbList"><li class="breadcrumbs__item"><a class="breadcrumbs__link" href="/awesome-interview/">🏠</a></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item"><span class="breadcrumbs__link" itemprop="item name">模拟题二</span><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="item name">样式：谈谈 CSS 预处理器</span><meta itemprop="position" content="2"></li></ul></nav><div class="tocCollapsible_jdIR theme-doc-toc-mobile tocMobile_TmEX"><button type="button" class="clean-btn tocCollapsibleButton_Fzxq">On this page</button></div><div class="theme-doc-markdown markdown"><h1>谈谈 CSS 预处理器</h1><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="相关问题">相关问题<a class="hash-link" href="#相关问题" title="Direct link to heading"></a></h2><ul><li>CSS 主要有哪些预处理器</li><li>为什么需要用预处理器</li><li>各预处理器优缺点</li></ul><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="回答关键点">回答关键点<a class="hash-link" href="#回答关键点" title="Direct link to heading"></a></h2><p><code>Sass</code> <code>Less</code> <code>Stylus</code> <code>PostCSS</code> <code>工程化</code> <code>提升效率</code></p><p>CSS 本身不属于可编程语言，当前端项目逐渐庞大之后 CSS 的维护也愈加困难。CSS 预处理器所做的本质上是为 CSS 增加一些可编程的特性，通过<strong>变量</strong>、<strong>嵌套</strong>、<strong>简单的程序逻辑</strong>、<strong>计算</strong>、<strong>函数</strong>等特性，通过<strong>工程化</strong>的手段让 CSS 更易维护，提升开发效率。</p><p>目前主流的 CSS 预处理器主要有 Sass、Less、Stylus、PostCSS。</p><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="知识点深入">知识点深入<a class="hash-link" href="#知识点深入" title="Direct link to heading"></a></h2><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="1-postcss1">1. PostCSS<sup>[1]</sup><a class="hash-link" href="#1-postcss1" title="Direct link to heading"></a></h3><p>PostCSS 是目前最为流行的 CSS 预/后处理器。PostCSS 本体功能比较单一，它提供一种用 JavaScript 来处理 CSS 的方式。PostCSS 会把 CSS 解析成 AST（Abstract Syntax Tree 抽象语法树），之后由其他插件进行不同的处理。</p><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="功能">功能<a class="hash-link" href="#功能" title="Direct link to heading"></a></h4><p>PostCSS 本体功能比较单一，大多数的 CSS 处理功能都由插件提供，下面是一些常用的插件：</p><ul><li><a href="https://github.com/postcss/autoprefixer" target="_blank" rel="noopener noreferrer">Autoprefixer</a> 为 CSS 中的属性添加浏览器特定的前缀。</li><li><a href="https://github.com/csstools/postcss-preset-env" target="_blank" rel="noopener noreferrer">postcss-preset-env</a> 根据 <code>browserslist</code> 指定的目标浏览器将一些 CSS 的新特性转换为目标浏览器所支持的语法。</li><li><a href="https://github.com/cssnano/cssnano" target="_blank" rel="noopener noreferrer">cssnano</a> 提供 CSS 压缩功能。</li><li><a href="https://github.com/postcss/postcss-nested" target="_blank" rel="noopener noreferrer">postcss-nested</a> 提供 CSS 嵌套功能。</li><li><a href="https://github.com/evrone/postcss-px-to-viewport" target="_blank" rel="noopener noreferrer">postcss-px-to-viewport</a> 提供 px 转 vw 功能。</li><li><a href="https://github.com/postcss/postcss-custom-properties" target="_blank" rel="noopener noreferrer">postcss-custom-properties</a> 支持 CSS 的自定义属性。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="优点">优点<a class="hash-link" href="#优点" title="Direct link to heading"></a></h4><ul><li>插件系统完善，扩展性强。</li><li>配合插件功能齐全。</li><li>生态优秀。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="缺点">缺点<a class="hash-link" href="#缺点" title="Direct link to heading"></a></h4><ul><li>配置相对复杂。</li></ul><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="2-sass2">2. Sass<sup>[2]</sup><a class="hash-link" href="#2-sass2" title="Direct link to heading"></a></h3><p>Sass 在完全兼容 CSS 语法的前提下，给 CSS 提供了变量、嵌套、混合、操作符、自定义函数等可编程能力。</p><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="功能-1">功能<a class="hash-link" href="#功能-1" title="Direct link to heading"></a></h4><p>Sass 常用的有几种功能：</p><ul><li>变量：变量中可以存储颜色、字体或任何 CSS 值。</li><li>嵌套：可嵌套 CSS 选择器，提供清晰的层次结构。</li><li>混合：可以定义&重用代码块。</li><li>扩展/集成：可以在一个选择器内继承另一个选择器。</li><li>操作符：可以在 CSS 中使用操作符进行计算。</li><li>条件/循环语句：可以循环/条件生成 CSS。</li><li>自定义函数：可以自定义复杂操作的函数。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="优点-1">优点<a class="hash-link" href="#优点-1" title="Direct link to heading"></a></h4><ul><li>使用广泛。</li><li>功能支持完善。</li><li>可编程能力强。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="缺点-1">缺点<a class="hash-link" href="#缺点-1" title="Direct link to heading"></a></h4><ul><li>CSS 的复杂度不可控。</li><li>node-sass 国内安装不易（非 Sass 本身的缺点，dart-sass 可代替）。</li></ul><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="3-less3">3. Less<sup>[3]</sup><a class="hash-link" href="#3-less3" title="Direct link to heading"></a></h3><p>Less 和 Sass 类似，完全兼容 CSS 语法，并给 CSS 提供了变量、嵌套、混合、运算等可编程能力。Less 通过 JavaScript 实现，可在浏览器端直接使用。</p><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="功能-2">功能<a class="hash-link" href="#功能-2" title="Direct link to heading"></a></h4><p>Less 常用的有几种功能：</p><ul><li>变量：变量中可以存储颜色、字体或任何 CSS 值。</li><li>嵌套：可嵌套 CSS 选择器，提供清晰的层次结构。</li><li>混合：可以定义&重用的代码块。</li><li>扩展/集成：可以在一个选择器内继承另一个选择器。</li><li>运算：可以在 CSS 中进行计算。</li><li>条件/循环语句：可以循环/条件生成 CSS。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="优点-2">优点<a class="hash-link" href="#优点-2" title="Direct link to heading"></a></h4><ul><li>使用广泛。</li><li>可以在浏览器中运行，容易实现主题定制功能。</li></ul><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="缺点-2">缺点<a class="hash-link" href="#缺点-2" title="Direct link to heading"></a></h4><ul><li>不支持自定义函数（可通过 mixins 实现简单逻辑）。</li><li>编程能力相对较弱。</li></ul><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="4-stylus4">4. Stylus<sup>[4]</sup><a class="hash-link" href="#4-stylus4" title="Direct link to heading"></a></h3><p>Stylus 基础功能和 Sass / Less 十分类似。Stylus 的特点是冒号、分号、逗号和括号都是可选项，所以可以写出非常简洁的 CSS，示例如下：</p><div class="codeBlockContainer_I0IT language-stylus theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-stylus codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token selector" style="color:#00009f">body</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property-declaration property" style="color:#36acaa">background-color</span><span class="token property-declaration punctuation" style="color:#393A34">:</span><span class="token property-declaration"> </span><span class="token property-declaration hexcode">#000</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token selector" style="color:#00009f">body::after</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property-declaration property" style="color:#36acaa">content</span><span class="token property-declaration punctuation" style="color:#393A34">:</span><span class="token property-declaration"> </span><span class="token property-declaration string" style="color:#e3116c">'HZFEStudio'</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property-declaration property" style="color:#36acaa">color</span><span class="token property-declaration punctuation" style="color:#393A34">:</span><span class="token property-declaration"> </span><span class="token property-declaration hexcode">#fff</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property-declaration property" style="color:#36acaa">font-size</span><span class="token property-declaration punctuation" style="color:#393A34">:</span><span class="token property-declaration"> </span><span class="token property-declaration number" style="color:#36acaa">20</span><span class="token property-declaration unit">px</span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="扩展阅读">扩展阅读<a class="hash-link" href="#扩展阅读" title="Direct link to heading"></a></h2><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="1-css-modules5">1. CSS Modules<sup>[5]</sup><a class="hash-link" href="#1-css-modules5" title="Direct link to heading"></a></h3><p>CSS Modules 和前文介绍的预处理器不同，不是可编程化的 CSS，而仅是给 CSS 文件加入了作用域和模块依赖，主要是为了解决 CSS 全局污染的痛点以及为了解决全局污染而嵌套过深的问题。使用示例如下：</p><div class="codeBlockContainer_I0IT language-css theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-css codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">/* style.css */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token selector class" style="color:#00009f">.hzfeTitle</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property" style="color:#36acaa">color</span><span class="token punctuation" style="color:#393A34">:</span><span class="token plain"> </span><span class="token hexcode color">#666</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token property" style="color:#36acaa">font-size</span><span class="token punctuation" style="color:#393A34">:</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">20</span><span class="token unit">px</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div><div class="codeBlockContainer_I0IT language-javascript theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-javascript codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token keyword module" style="color:#00009f">import</span><span class="token plain"> </span><span class="token imports">style</span><span class="token plain"> </span><span class="token keyword module" style="color:#00009f">from</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">"./style.css"</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token dom variable" style="color:#36acaa">document</span><span class="token punctuation" style="color:#393A34">.</span><span class="token property-access">body</span><span class="token punctuation" style="color:#393A34">.</span><span class="token property-access">innerHTML</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token template-string template-punctuation string" style="color:#e3116c">`</span><span class="token template-string html language-html tag punctuation" style="color:#393A34"><</span><span class="token template-string html language-html tag" style="color:#00009f">h1</span><span class="token template-string html language-html tag" style="color:#00009f"> </span><span class="token template-string html language-html tag attr-name" style="color:#00a4db">class</span><span class="token template-string html language-html tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token template-string html language-html tag attr-value punctuation" style="color:#393A34">"</span><span class="token template-string html language-html tag attr-value interpolation interpolation-punctuation punctuation" style="color:#393A34">${</span><span class="token template-string html language-html tag attr-value interpolation" style="color:#e3116c">style</span><span class="token template-string html language-html tag attr-value interpolation punctuation" style="color:#393A34">.</span><span class="token template-string html language-html tag attr-value interpolation property-access" style="color:#e3116c">hzfeTitle</span><span class="token template-string html language-html tag attr-value interpolation interpolation-punctuation punctuation" style="color:#393A34">}</span><span class="token template-string html language-html tag attr-value punctuation" style="color:#393A34">"</span><span class="token template-string html language-html tag punctuation" style="color:#393A34">></span><span class="token template-string html language-html">HZFEStudio</span><span class="token template-string html language-html tag punctuation" style="color:#393A34"></</span><span class="token template-string html language-html tag" style="color:#00009f">h1</span><span class="token template-string html language-html tag punctuation" style="color:#393A34">></span><span class="token template-string template-punctuation string" style="color:#e3116c">`</span><span class="token punctuation" style="color:#393A34">;</span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="2-css-in-js">2. CSS-in-JS<a class="hash-link" href="#2-css-in-js" title="Direct link to heading"></a></h3><p>如名字所见，CSS-in-JS 是一种在 JavaScript 里写 CSS 的方式。利用 JS 的优势可实现非常灵活的可扩展的样式。CSS-in-JS 有很多实现，目前比较流行的是 <a href="https://www.styled-components.com/" target="_blank" rel="noopener noreferrer">Styled-components</a>。</p><p>通过 Styled-components 写 CSS 的示例如下：</p><div class="codeBlockContainer_I0IT language-javascript theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-javascript codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token keyword module" style="color:#00009f">import</span><span class="token plain"> </span><span class="token imports maybe-class-name">React</span><span class="token plain"> </span><span class="token keyword module" style="color:#00009f">from</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">"react"</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword module" style="color:#00009f">import</span><span class="token plain"> </span><span class="token imports">styled</span><span class="token plain"> </span><span class="token keyword module" style="color:#00009f">from</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">"styled-components"</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">function</span><span class="token plain"> </span><span class="token function" style="color:#d73a49">hzfe</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> </span><span class="token maybe-class-name">Title</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> styled</span><span class="token punctuation" style="color:#393A34">.</span><span class="token property-access">h1</span><span class="token template-string template-punctuation string" style="color:#e3116c">`</span><span class="token template-string css language-css"></span><br></span><span class="token-line" style="color:#393A34"><span class="token template-string css language-css"> </span><span class="token template-string css language-css property" style="color:#36acaa">font-size</span><span class="token template-string css language-css punctuation" style="color:#393A34">:</span><span class="token template-string css language-css"> </span><span class="token template-string css language-css number" style="color:#36acaa">1.5</span><span class="token template-string css language-css unit">em</span><span class="token template-string css language-css punctuation" style="color:#393A34">;</span><span class="token template-string css language-css"></span><br></span><span class="token-line" style="color:#393A34"><span class="token template-string css language-css"> </span><span class="token template-string css language-css property" style="color:#36acaa">text-align</span><span class="token template-string css language-css punctuation" style="color:#393A34">:</span><span class="token template-string css language-css"> center</span><span class="token template-string css language-css punctuation" style="color:#393A34">;</span><span class="token template-string css language-css"></span><br></span><span class="token-line" style="color:#393A34"><span class="token template-string css language-css"> </span><span class="token template-string css language-css property" style="color:#36acaa">color</span><span class="token template-string css language-css punctuation" style="color:#393A34">:</span><span class="token template-string css language-css"> </span><span class="token template-string css language-css hexcode color">#666</span><span class="token template-string css language-css punctuation" style="color:#393A34">;</span><span class="token template-string css language-css"></span><br></span><span class="token-line" style="color:#393A34"><span class="token template-string css language-css"> </span><span class="token template-string template-punctuation string" style="color:#e3116c">`</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword control-flow" style="color:#00009f">return</span><span class="token plain"> </span><span class="token operator" style="color:#393A34"><</span><span class="token maybe-class-name">Title</span><span class="token operator" style="color:#393A34">></span><span class="token maybe-class-name">HZFEStudio</span><span class="token operator" style="color:#393A34"><</span><span class="token operator" style="color:#393A34">/</span><span class="token maybe-class-name">Title</span><span class="token operator" style="color:#393A34">></span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="3-tailwind-和-utility-first-css">3. Tailwind 和 Utility-first CSS<a class="hash-link" href="#3-tailwind-和-utility-first-css" title="Direct link to heading"></a></h3><p>近几年随着 Tailwind 的流行，功能类优先（Utility-first CSS）的理念也再次流行起来。这里简单介绍一下 Tailwind CSS。</p><h4 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="31-tailwind6">3.1 Tailwind<sup>[6]</sup><a class="hash-link" href="#31-tailwind6" title="Direct link to heading"></a></h4><p>Tailwind CSS 是一个功能类优先的 CSS 框架，通过组合不同的类名实现页面设计。Tailwind 主要优势如下：</p><ol><li>不用考虑 class 的命名。</li><li>CSS 文件大小增长可控，通过 <code>purge</code> 可生成非常小的 CSS 文件。</li><li>统一设计系统下的样式与布局。</li><li>IDE 集成优秀。</li></ol><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="参考资料">参考资料<a class="hash-link" href="#参考资料" title="Direct link to heading"></a></h2><ol><li><a href="https://postcss.org/" target="_blank" rel="noopener noreferrer">PostCSS - A tool for transforming CSS with JavaScript</a></li><li><a href="https://sass-lang.com/" target="_blank" rel="noopener noreferrer">Sass - CSS with superpowers</a></li><li><a href="https://lesscss.org/" target="_blank" rel="noopener noreferrer">Less - It's CSS, with just a little more</a></li><li><a href="https://stylus-lang.com/" target="_blank" rel="noopener noreferrer">Stylus - Foresight has never been so crucial</a></li><li><a href="https://github.com/css-modules/css-modules" target="_blank" rel="noopener noreferrer">CSS Modules</a></li><li><a href="https://tailwindcss.com/" target="_blank" rel="noopener noreferrer">Tailwind CSS</a></li></ol></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages navigation"><div class="pagination-nav__item"><a class="pagination-nav__link" href="/awesome-interview/book2/js-new"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">基础：New 操作符的原理</div></a></div><div class="pagination-nav__item pagination-nav__item--next"><a class="pagination-nav__link" href="/awesome-interview/book2/network-http-cache"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">网络：HTTP 缓存机制</div></a></div></nav></div></div><div class="col col--3"><div class="tableOfContents_cNA8 thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#相关问题" class="table-of-contents__link toc-highlight">相关问题</a></li><li><a href="#回答关键点" class="table-of-contents__link toc-highlight">回答关键点</a></li><li><a href="#知识点深入" class="table-of-contents__link toc-highlight">知识点深入</a><ul><li><a href="#1-postcss1" class="table-of-contents__link toc-highlight">1. PostCSS<sup>1</sup></a><ul><li><a href="#功能" class="table-of-contents__link toc-highlight">功能</a></li><li><a href="#优点" class="table-of-contents__link toc-highlight">优点</a></li><li><a href="#缺点" class="table-of-contents__link toc-highlight">缺点</a></li></ul></li><li><a href="#2-sass2" class="table-of-contents__link toc-highlight">2. Sass<sup>2</sup></a><ul><li><a href="#功能-1" class="table-of-contents__link toc-highlight">功能</a></li><li><a href="#优点-1" class="table-of-contents__link toc-highlight">优点</a></li><li><a href="#缺点-1" class="table-of-contents__link toc-highlight">缺点</a></li></ul></li><li><a href="#3-less3" class="table-of-contents__link toc-highlight">3. Less<sup>3</sup></a><ul><li><a href="#功能-2" class="table-of-contents__link toc-highlight">功能</a></li><li><a href="#优点-2" class="table-of-contents__link toc-highlight">优点</a></li><li><a href="#缺点-2" class="table-of-contents__link toc-highlight">缺点</a></li></ul></li><li><a href="#4-stylus4" class="table-of-contents__link toc-highlight">4. Stylus<sup>4</sup></a></li></ul></li><li><a href="#扩展阅读" class="table-of-contents__link toc-highlight">扩展阅读</a><ul><li><a href="#1-css-modules5" class="table-of-contents__link toc-highlight">1. CSS Modules<sup>5</sup></a></li><li><a href="#2-css-in-js" class="table-of-contents__link toc-highlight">2. CSS-in-JS</a></li><li><a href="#3-tailwind-和-utility-first-css" class="table-of-contents__link toc-highlight">3. Tailwind 和 Utility-first CSS</a><ul><li><a href="#31-tailwind6" class="table-of-contents__link toc-highlight">3.1 Tailwind<sup>6</sup></a></li></ul></li></ul></li><li><a href="#参考资料" class="table-of-contents__link toc-highlight">参考资料</a></li></ul></div></div></div><div class="row"><div class="col"><div class="react-utterences"><div>Loading script...</div></div></div><div class="col col--3"></div></div></div></main></div></div></div>
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