03. CSS3高级特性和预处理器

📋 目录

现代CSS布局系统
CSS动画和变换
响应式设计深入
CSS架构方法论
预处理器深入
CSS-in-JS方案

现代CSS布局系统

CSS3 引入了Flexbox 和Grid 两大布局系统，彻底改变了Web布局的方式，让复杂布局变得简单直观。

Flexbox布局详解


/* Flexbox容器属性 */
.flex-container {
  display: flex;
  
  /* 主轴方向 */
  flex-direction: row | row-reverse | column | column-reverse;
  
  /* 换行方式 */
  flex-wrap: nowrap | wrap | wrap-reverse;
  
  /* 简写：flex-direction + flex-wrap */
  flex-flow: row wrap;
  
  /* 主轴对齐 */
  justify-content: flex-start | flex-end | center | space-between | space-around | space-evenly;
  
  /* 交叉轴对齐 */
  align-items: stretch | flex-start | flex-end | center | baseline;
  
  /* 多行交叉轴对齐 */
  align-content: stretch | flex-start | flex-end | center | space-between | space-around;
  
  /* 间距 */
  gap: 1rem; /* 或者 row-gap: 1rem; column-gap: 1rem; */
}
 
/* Flexbox项目属性 */
.flex-item {
  /* 放大比例 */
  flex-grow: 0; /* 默认不放大 */
  
  /* 缩小比例 */
  flex-shrink: 1; /* 默认可缩小 */
  
  /* 基础大小 */
  flex-basis: auto; /* 默认为auto */
  
  /* 简写：flex-grow + flex-shrink + flex-basis */
  flex: 1; /* 等同于 flex: 1 1 0% */
  flex: auto; /* 等同于 flex: 1 1 auto */
  flex: none; /* 等同于 flex: 0 0 auto */
  
  /* 单独对齐 */
  align-self: auto | flex-start | flex-end | center | baseline | stretch;
  
  /* 排序 */
  order: 0; /* 默认为0，数值越小越靠前 */
}

Flexbox实战案例


<!-- 经典的三栏布局 -->
<div class="layout">
  <header class="header">头部</header>
  <main class="main">
    <aside class="sidebar">侧边栏</aside>
    <section class="content">主内容</section>
  </main>
  <footer class="footer">底部</footer>
</div>
 
<style>
.layout {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
 
.header, .footer {
  background: #333;
  color: white;
  padding: 1rem;
  flex-shrink: 0; /* 防止收缩 */
}
 
.main {
  flex: 1; /* 占据剩余空间 */
  display: flex;
}
 
.sidebar {
  width: 250px;
  background: #f5f5f5;
  padding: 1rem;
  flex-shrink: 0;
}
 
.content {
  flex: 1;
  padding: 1rem;
  background: white;
}
 
/* 响应式：小屏幕时垂直排列 */
@media (max-width: 768px) {
  .main {
    flex-direction: column;
  }
  
  .sidebar {
    width: auto;
    order: 2; /* 移到内容下方 */
  }
}
</style>
 
<!-- 卡片网格布局 -->
<div class="card-grid">
  <div class="card">卡片1</div>
  <div class="card">卡片2</div>
  <div class="card">卡片3</div>
  <div class="card">卡片4</div>
</div>
 
<style>
.card-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  padding: 1rem;
}
 
.card {
  flex: 1 1 300px; /* 最小宽度300px，可伸缩 */
  min-height: 200px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 8px;
  padding: 1rem;
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
}
</style>

CSS Grid布局详解

⚠️

CSS Grid是二维布局系统，比Flexbox更适合复杂的网格布局。掌握Grid能让你轻松实现各种复杂的布局需求。


/* Grid容器属性 */
.grid-container {
  display: grid;
  
  /* 定义列 */
  grid-template-columns: 200px 1fr 100px; /* 固定-自适应-固定 */
  grid-template-columns: repeat(3, 1fr); /* 三等分 */
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); /* 响应式网格 */
  
  /* 定义行 */
  grid-template-rows: 60px 1fr 40px;
  grid-template-rows: repeat(3, 100px);
  
  /* 定义区域 */
  grid-template-areas: 
    "header header header"
    "sidebar content content"
    "footer footer footer";
  
  /* 间距 */
  gap: 1rem; /* 或者 row-gap: 1rem; column-gap: 1rem; */
  
  /* 对齐方式 */
  justify-items: start | end | center | stretch;
  align-items: start | end | center | stretch;
  justify-content: start | end | center | stretch | space-around | space-between | space-evenly;
  align-content: start | end | center | stretch | space-around | space-between | space-evenly;
}
 
/* Grid项目属性 */
.grid-item {
  /* 指定位置 */
  grid-column: 1 / 3; /* 从第1列到第3列 */
  grid-row: 2 / 4; /* 从第2行到第4行 */
  
  /* 简写 */
  grid-area: 2 / 1 / 4 / 3; /* row-start / col-start / row-end / col-end */
  
  /* 使用命名区域 */
  grid-area: header;
  
  /* 跨越 */
  grid-column: span 2; /* 跨越2列 */
  grid-row: span 3; /* 跨越3行 */
  
  /* 单独对齐 */
  justify-self: start | end | center | stretch;
  align-self: start | end | center | stretch;
}

Grid实战案例


<!-- 经典网站布局 -->
<div class="website-layout">
  <header class="header">网站头部</header>
  <nav class="nav">导航栏</nav>
  <aside class="sidebar">侧边栏</aside>
  <main class="content">主要内容</main>
  <footer class="footer">网站底部</footer>
</div>
 
<style>
.website-layout {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 200px 1fr;
  grid-template-rows: 80px 60px 1fr 60px;
  grid-template-areas:
    "header header"
    "nav nav"
    "sidebar content"
    "footer footer";
  gap: 1rem;
  padding: 1rem;
}
 
.header { grid-area: header; background: #333; color: white; }
.nav { grid-area: nav; background: #666; color: white; }
.sidebar { grid-area: sidebar; background: #f5f5f5; }
.content { grid-area: content; background: white; }
.footer { grid-area: footer; background: #333; color: white; }
 
/* 响应式调整 */
@media (max-width: 768px) {
  .website-layout {
    grid-template-columns: 1fr;
    grid-template-areas:
      "header"
      "nav"
      "content"
      "sidebar"
      "footer";
  }
}
</style>
 
<!-- 响应式卡片网格 -->
<div class="responsive-grid">
  <div class="card">卡片 1</div>
  <div class="card featured">特色卡片</div>
  <div class="card">卡片 3</div>
  <div class="card">卡片 4</div>
  <div class="card">卡片 5</div>
  <div class="card">卡片 6</div>
</div>
 
<style>
.responsive-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1rem;
  padding: 1rem;
}
 
.card {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 8px;
  padding: 1rem;
  color: white;
  min-height: 150px;
  display: flex;
  align-items: center;
  justify-content: center;
}
 
.featured {
  grid-column: span 2; /* 特色卡片占两列 */
  background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}
 
/* 确保在小屏幕上特色卡片不会过宽 */
@media (max-width: 600px) {
  .featured {
    grid-column: span 1;
  }
}
</style>

CSS动画和变换

Transform变换


/* 2D变换 */
.transform-2d {
  /* 平移 */
  transform: translate(50px, 100px);
  transform: translateX(50px);
  transform: translateY(100px);
  
  /* 缩放 */
  transform: scale(1.5);
  transform: scale(2, 0.5); /* X轴2倍，Y轴0.5倍 */
  transform: scaleX(2);
  transform: scaleY(0.5);
  
  /* 旋转 */
  transform: rotate(45deg);
  
  /* 倾斜 */
  transform: skew(30deg, 20deg);
  transform: skewX(30deg);
  transform: skewY(20deg);
  
  /* 组合变换 */
  transform: translate(50px, 100px) rotate(45deg) scale(1.2);
}
 
/* 3D变换 */
.transform-3d {
  /* 启用3D空间 */
  transform-style: preserve-3d;
  perspective: 1000px;
  
  /* 3D平移 */
  transform: translate3d(50px, 100px, 200px);
  transform: translateZ(200px);
  
  /* 3D旋转 */
  transform: rotateX(45deg);
  transform: rotateY(45deg);
  transform: rotateZ(45deg);
  transform: rotate3d(1, 1, 0, 45deg);
  
  /* 3D缩放 */
  transform: scale3d(2, 1, 0.5);
  transform: scaleZ(2);
}
 
/* 变换原点 */
.transform-origin {
  transform-origin: center center; /* 默认 */
  transform-origin: top left;
  transform-origin: 50% 50%;
  transform-origin: 10px 20px;
}

CSS动画


/* 关键帧动画 */
@keyframes slideIn {
  from {
    transform: translateX(-100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}
 
@keyframes bounce {
  0%, 20%, 53%, 80%, 100% {
    transform: translate3d(0, 0, 0);
  }
  40%, 43% {
    transform: translate3d(0, -30px, 0);
  }
  70% {
    transform: translate3d(0, -15px, 0);
  }
  90% {
    transform: translate3d(0, -4px, 0);
  }
}
 
@keyframes pulse {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.1);
  }
  100% {
    transform: scale(1);
  }
}
 
/* 应用动画 */
.animated {
  animation-name: slideIn;
  animation-duration: 0.5s;
  animation-timing-function: ease-out;
  animation-delay: 0.2s;
  animation-iteration-count: 1;
  animation-direction: normal;
  animation-fill-mode: forwards;
  animation-play-state: running;
  
  /* 简写 */
  animation: slideIn 0.5s ease-out 0.2s 1 normal forwards;
}
 
.bounce-animation {
  animation: bounce 2s infinite;
}
 
.pulse-animation {
  animation: pulse 1s ease-in-out infinite alternate;
}

过渡效果


/* 基础过渡 */
.transition-basic {
  transition-property: all;
  transition-duration: 0.3s;
  transition-timing-function: ease;
  transition-delay: 0s;
  
  /* 简写 */
  transition: all 0.3s ease;
}
 
/* 多属性过渡 */
.transition-multiple {
  transition: 
    background-color 0.3s ease,
    transform 0.2s ease-out,
    opacity 0.4s linear;
}
 
/* 实用的过渡效果 */
.button {
  background: #007bff;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
}
 
.button:hover {
  background: #0056b3;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}
 
.button:active {
  transform: translateY(0);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}
 
/* 卡片悬停效果 */
.card {
  background: white;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  cursor: pointer;
}
 
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

响应式设计深入

媒体查询高级用法

现代响应式设计不仅仅是屏幕尺寸适配，还要考虑设备特性、用户偏好等多个维度。


/* 基础媒体查询 */
@media screen and (max-width: 768px) {
  /* 移动端样式 */
}
 
@media screen and (min-width: 769px) and (max-width: 1024px) {
  /* 平板端样式 */
}
 
@media screen and (min-width: 1025px) {
  /* 桌面端样式 */
}
 
/* 高级媒体查询 */
@media screen and (orientation: landscape) {
  /* 横屏样式 */
}
 
@media screen and (orientation: portrait) {
  /* 竖屏样式 */
}
 
@media screen and (min-resolution: 2dppx) {
  /* 高分辨率屏幕（Retina等） */
}
 
@media (prefers-color-scheme: dark) {
  /* 用户偏好暗色主题 */
  :root {
    --bg-color: #1a1a1a;
    --text-color: #ffffff;
  }
}
 
@media (prefers-reduced-motion: reduce) {
  /* 用户偏好减少动画 */
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}
 
@media (hover: hover) {
  /* 支持悬停的设备 */
  .button:hover {
    background-color: #0056b3;
  }
}
 
@media (hover: none) {
  /* 不支持悬停的设备（触摸设备） */
  .button:active {
    background-color: #0056b3;
  }
}

容器查询


/* 容器查询（现代浏览器支持） */
.card-container {
  container-type: inline-size;
  container-name: card;
}
 
@container card (min-width: 300px) {
  .card {
    display: flex;
    flex-direction: row;
  }
  
  .card-image {
    width: 150px;
  }
}
 
@container card (max-width: 299px) {
  .card {
    display: flex;
    flex-direction: column;
  }
  
  .card-image {
    width: 100%;
  }
}

现代CSS单位


/* 视口单位 */
.hero {
  height: 100vh; /* 视口高度 */
  width: 100vw; /* 视口宽度 */
  font-size: 4vw; /* 视口宽度的4% */
}
 
/* 新的视口单位（解决移动端地址栏问题） */
.mobile-hero {
  height: 100dvh; /* 动态视口高度 */
  height: 100svh; /* 小视口高度 */
  height: 100lvh; /* 大视口高度 */
}
 
/* 容器单位 */
.responsive-text {
  font-size: clamp(1rem, 4cqw, 2rem); /* 容器查询宽度 */
}
 
/* 逻辑属性 */
.logical-spacing {
  margin-block: 1rem; /* margin-top + margin-bottom */
  margin-inline: 2rem; /* margin-left + margin-right */
  padding-block-start: 0.5rem; /* padding-top */
  padding-block-end: 0.5rem; /* padding-bottom */
  padding-inline-start: 1rem; /* padding-left (LTR) / padding-right (RTL) */
  padding-inline-end: 1rem; /* padding-right (LTR) / padding-left (RTL) */
}
 
/* 数学函数 */
.math-functions {
  width: calc(100% - 2rem);
  font-size: clamp(1rem, 2.5vw, 2rem); /* 最小值, 首选值, 最大值 */
  margin: max(1rem, 5%); /* 取较大值 */
  padding: min(2rem, 10%); /* 取较小值 */
}

CSS架构方法论

BEM方法论

⚠️

BEM（Block Element Modifier）是一种CSS命名约定，能够让CSS更加模块化和可维护。


/* BEM命名规范 */
/* Block（块） */
.card { }
 
/* Element（元素） */
.card__header { }
.card__body { }
.card__footer { }
.card__title { }
.card__description { }
.card__button { }
 
/* Modifier（修饰符） */
.card--featured { } /* 特色卡片 */
.card--large { } /* 大尺寸卡片 */
.card__button--primary { } /* 主要按钮 */
.card__button--disabled { } /* 禁用按钮 */
 
/* 实际应用 */
.product-card {
  background: white;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  overflow: hidden;
}
 
.product-card--featured {
  border: 2px solid #007bff;
  box-shadow: 0 4px 12px rgba(0, 123, 255, 0.3);
}
 
.product-card__image {
  width: 100%;
  height: 200px;
  object-fit: cover;
}
 
.product-card__content {
  padding: 1rem;
}
 
.product-card__title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #333;
}
 
.product-card__title--large {
  font-size: 1.5rem;
}
 
.product-card__description {
  color: #666;
  line-height: 1.5;
  margin-bottom: 1rem;
}
 
.product-card__price {
  font-size: 1.125rem;
  font-weight: 700;
  color: #007bff;
}
 
.product-card__button {
  background: #007bff;
  color: white;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  cursor: pointer;
  transition: background-color 0.2s;
}
 
.product-card__button--secondary {
  background: #6c757d;
}
 
.product-card__button--disabled {
  background: #e9ecef;
  color: #6c757d;
  cursor: not-allowed;
}

OOCSS（面向对象CSS）


/* 结构与皮肤分离 */
/* 结构类 */
.btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  border: 1px solid transparent;
  border-radius: 4px;
  text-decoration: none;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
}
 
/* 皮肤类 */
.btn-primary {
  background: #007bff;
  color: white;
  border-color: #007bff;
}
 
.btn-secondary {
  background: #6c757d;
  color: white;
  border-color: #6c757d;
}
 
.btn-outline {
  background: transparent;
  color: #007bff;
  border-color: #007bff;
}
 
/* 容器与内容分离 */
.media {
  display: flex;
  align-items: flex-start;
}
 
.media__object {
  flex-shrink: 0;
  margin-right: 1rem;
}
 
.media__body {
  flex: 1;
}
 
/* 使用示例 */
/* <div class="media">
     <img src="avatar.jpg" class="media__object" alt="Avatar">
     <div class="media__body">
       <h5>用户名</h5>
       <p>用户描述...</p>
     </div>
   </div> */

原子化CSS（Atomic CSS）


/* 原子化工具类 */
/* 间距 */
.m-0 { margin: 0; }
.m-1 { margin: 0.25rem; }
.m-2 { margin: 0.5rem; }
.m-3 { margin: 0.75rem; }
.m-4 { margin: 1rem; }
 
.mt-1 { margin-top: 0.25rem; }
.mr-1 { margin-right: 0.25rem; }
.mb-1 { margin-bottom: 0.25rem; }
.ml-1 { margin-left: 0.25rem; }
 
.p-0 { padding: 0; }
.p-1 { padding: 0.25rem; }
.p-2 { padding: 0.5rem; }
.p-3 { padding: 0.75rem; }
.p-4 { padding: 1rem; }
 
/* 显示 */
.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-flex { display: flex; }
.d-grid { display: grid; }
 
/* Flexbox */
.flex-row { flex-direction: row; }
.flex-column { flex-direction: column; }
.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.items-start { align-items: flex-start; }
.items-center { align-items: center; }
.items-end { align-items: flex-end; }
 
/* 文本 */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-sm { font-size: 0.875rem; }
.text-base { font-size: 1rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }
.font-normal { font-weight: 400; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }
 
/* 颜色 */
.text-gray-500 { color: #6b7280; }
.text-gray-900 { color: #111827; }
.text-blue-500 { color: #3b82f6; }
.text-red-500 { color: #ef4444; }
.bg-white { background-color: #ffffff; }
.bg-gray-100 { background-color: #f3f4f6; }
.bg-blue-500 { background-color: #3b82f6; }
 
/* 边框 */
.border { border: 1px solid #e5e7eb; }
.border-0 { border: 0; }
.border-t { border-top: 1px solid #e5e7eb; }
.border-gray-200 { border-color: #e5e7eb; }
.rounded { border-radius: 0.25rem; }
.rounded-md { border-radius: 0.375rem; }
.rounded-lg { border-radius: 0.5rem; }
.rounded-full { border-radius: 9999px; }
 
/* 阴影 */
.shadow-sm { box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05); }
.shadow { box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06); }
.shadow-md { box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06); }
.shadow-lg { box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05); }

预处理器深入

CSS预处理器如Sass 、Less 等为CSS开发提供了变量、嵌套、混合等强大功能。

Sass/SCSS 高级特性


// 变量和嵌套
$primary-color: #007bff;
$secondary-color: #6c757d;
$border-radius: 4px;
 
.card {
  background: white;
  border-radius: $border-radius;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
 
  &__header {
    padding: 1rem;
    border-bottom: 1px solid #dee2e6;
 
    h3 {
      margin: 0;
      color: $primary-color;
    }
  }
 
  &__body {
    padding: 1rem;
  }
 
  &--highlighted {
    border-left: 4px solid $primary-color;
  }
}
 
// 混合(Mixins)
@mixin button-style($bg-color, $text-color: white) {
  background-color: $bg-color;
  color: $text-color;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: $border-radius;
  cursor: pointer;
  transition: all 0.3s ease;
 
  &:hover {
    background-color: darken($bg-color, 10%);
    transform: translateY(-1px);
  }
}
 
.btn-primary {
  @include button-style($primary-color);
}
 
.btn-secondary {
  @include button-style($secondary-color);
}

CSS-in-JS方案

CSS-in-JS允许在JavaScript中编写CSS，提供了动态样式、主题切换、作用域隔离等优势。

Styled Components


import styled, { ThemeProvider, createGlobalStyle } from 'styled-components';
 
// 全局样式
const GlobalStyle = createGlobalStyle`
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
 
  body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    background-color: ${props => props.theme.backgroundColor};
    color: ${props => props.theme.textColor};
  }
`;
 
// 主题定义
const lightTheme = {
  backgroundColor: '#ffffff',
  textColor: '#333333',
  primaryColor: '#007bff',
  secondaryColor: '#6c757d'
};
 
const darkTheme = {
  backgroundColor: '#1a1a1a',
  textColor: '#ffffff',
  primaryColor: '#0d6efd',
  secondaryColor: '#6c757d'
};
 
// 样式组件
const Button = styled.button`
  background-color: ${props => props.theme.primaryColor};
  color: white;
  border: none;
  padding: ${props => props.size === 'large' ? '12px 24px' : '8px 16px'};
  border-radius: 4px;
  cursor: pointer;
  font-size: ${props => props.size === 'large' ? '16px' : '14px'};
  transition: all 0.3s ease;
 
  &:hover {
    background-color: ${props => props.theme.primaryColor}dd;
    transform: translateY(-1px);
  }
 
  &:disabled {
    background-color: ${props => props.theme.secondaryColor};
    cursor: not-allowed;
    transform: none;
  }
`;
 
const Card = styled.div`
  background: ${props => props.theme.backgroundColor};
  border: 1px solid ${props => props.theme.textColor}20;
  border-radius: 8px;
  padding: 1rem;
  margin: 1rem 0;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
`;
 
// 使用示例
function App() {
  const [isDarkMode, setIsDarkMode] = useState(false);
 
  return (
    <ThemeProvider theme={isDarkMode ? darkTheme : lightTheme}>
      <GlobalStyle />
      <Card>
        <h2>CSS-in-JS 示例</h2>
        <Button onClick={() => setIsDarkMode(!isDarkMode)}>
          切换主题
        </Button>
        <Button size="large" disabled>
          大按钮（禁用）
        </Button>
      </Card>
    </ThemeProvider>
  );
}

Emotion


/** @jsxImportSource @emotion/react */
import { css, Global, ThemeProvider } from '@emotion/react';
import styled from '@emotion/styled';
 
// 全局样式
const globalStyles = css`
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
`;
 
// CSS对象样式
const buttonStyles = (theme) => css`
  background-color: ${theme.primaryColor};
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 4px;
  cursor: pointer;
 
  &:hover {
    background-color: ${theme.primaryColor}dd;
  }
`;
 
// Styled组件
const StyledCard = styled.div`
  background: white;
  border-radius: 8px;
  padding: 1rem;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
`;
 
function MyComponent() {
  const theme = { primaryColor: '#007bff' };
 
  return (
    <ThemeProvider theme={theme}>
      <Global styles={globalStyles} />
      <StyledCard>
        <button css={buttonStyles}>点击我</button>
      </StyledCard>
    </ThemeProvider>
  );
}

CSS3的强大功能让我们能够创建出美观、响应式、高性能的用户界面。掌握现代CSS布局、动画和架构方法论，是成为优秀前端开发者的必备技能。

📚 参考学习资料

📖 官方文档

MDN CSS 参考 - CSS权威文档
CSS 规范 - W3C CSS标准
Can I Use - CSS特性兼容性查询

🎓 优质教程

CSS-Tricks - CSS技巧和教程
Flexbox Froggy - Flexbox游戏教程
Grid Garden - CSS Grid游戏教程
CSS Layout - CSS布局学习

🛠️ 实践项目

CSS Zen Garden - CSS设计展示
30 Seconds of CSS - CSS代码片段
Animate.css - CSS动画库

🔧 开发工具

Sass - CSS预处理器
PostCSS - CSS后处理器
Tailwind CSS - 实用优先的CSS框架
CSS Grid Generator - Grid布局生成器

📝 深入阅读

CSS 架构指南 - CSS架构最佳实践
BEM 方法论 - CSS命名规范
CSS 性能优化 - 性能优化指南

💡 学习建议：建议先掌握Flexbox和Grid布局，然后学习CSS动画和预处理器，最后了解CSS架构方法论和性能优化。