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CSS教程手册 CSS高级 CSS基础教程 CSS中级教程 CSS3高级教程 CSS响应式设计 CSS网格教程 CSS实例

参考手册浏览器支持参考手册选择器参考手册组合器参考手册伪类参考手册伪元素参考手册函数参考手册动画相关属性网络安全字体字体回退单位颜色合法颜色值默认值参考手册实体听觉参考手册 accent-color align-content align-items align-self all animation animation-delay animation-direction animation-duration animation-fill-mode animation-iteration-count animation-name animation-play-state animation-timing-function aspect-ratio backdrop-filter backface-visibility background background-attachment background-blend-mode background-clip background-color background-image background-origin background-position background-position-x background-position-y background-repeat background-size block-size border border-block border-block-color border-block-end border-block-end-color border-block-end-style border-block-end-width border-block-start border-block-start-color border-block-start-style border-block-start-width border-block-style border-block-width border-bottom border-bottom-color border-bottom-left-radius border-bottom-right-radius border-bottom-style border-bottom-width border-collapse border-color border-end-end-radius border-end-start-radius border-image border-image-outset border-image-repeat border-image-slice border-image-source border-image-width border-inline border-inline-color border-inline-end border-inline-end-color border-inline-end-style border-inline-end-width border-inline-start border-inline-start-color border-inline-start-style border-inline-start-width border-inline-style border-inline-width border-left border-left-color border-left-style border-left-width border-radius border-right border-right-color border-right-style border-right-width border-spacing border-start-end-radius border-start-start-radius border-style border-top border-top-color border-top-left-radius border-top-right-radius border-top-style border-top-width border-width bottom box-decoration-break box-reflect box-shadow box-sizing break-after break-before break-inside caption-side caret-color @charset 规则 clear clip clip-path color color-scheme column-count column-fill column-gap column-rule column-rule-color column-rule-style column-rule-width column-span column-width columns @container 规则 content counter-increment counter-reset counter-set @counter-style 规则 cursor direction display empty-cells filter flex flex-basis flex-direction flex-flow flex-grow flex-shrink flex-wrap float font @font-face 规则 font-family font-feature-settings font-kerning @font-palette-values 规则 font-size font-size-adjust font-stretch font-style font-variant font-variant-caps font-weight gap grid grid-area grid-auto-columns grid-auto-flow grid-auto-rows grid-column grid-column-end grid-column-gap grid-column-start grid-gap grid-row grid-row-end grid-row-gap grid-row-start grid-template grid-template-areas grid-template-columns grid-template-rows hanging-punctuation height hyphens hyphenate-character image-rendering @import 规则 initial-letter inline-size inset inset-block inset-block-end inset-block-start inset-inline inset-inline-end inset-inline-start isolation justify-content justify-items justify-self @keyframes 规则 @layer 规则 left letter-spacing line-height list-style list-style-image list-style-position list-style-type margin margin-block margin-block-end margin-block-start margin-bottom margin-inline margin-inline-end margin-inline-start margin-left margin-right margin-top marker marker-end marker-mid marker-start mask mask-clip mask-composite mask-image mask-mode mask-origin mask-position mask-repeat mask-size mask-type max-block-size max-height max-inline-size max-width @media 规则 min-block-size min-inline-size min-height min-width mix-blend-mode @namespace 规则 object-fit object-position offset offset-anchor offset-distance offset-path offset-position offset-rotate opacity order orphans outline outline-color outline-offset outline-style outline-width overflow overflow-anchor overflow-wrap overflow-x overflow-y overscroll-behavior overscroll-behavior-block overscroll-behavior-inline overscroll-behavior-x overscroll-behavior-y padding padding-block padding-block-end padding-block-start padding-bottom padding-inline padding-inline-end padding-inline-start padding-left padding-top @page 规则 page-break-inside paint-order perspective perspective-origin place-content place-items place-self pointer-events position @property 规则 quotes resize right rotate row-gap scale @scope 规则 scroll-behavior scroll-margin scroll-margin-block scroll-margin-block-end scroll-margin-block-start scroll-margin-bottom scroll-margin-inline scroll-margin-inline-end scroll-margin-inline-start scroll-margin-left scroll-margin-right scroll-margin-top scroll-padding scroll-padding-block scroll-padding-block-end scroll-padding-block-start scroll-padding-bottom scroll-padding-inline scroll-padding-inline-end scroll-padding-inline-start scroll-padding-right scroll-padding-top scroll-snap-stop scroll-snap-type scrollbar-color shape-outside @starting-style 规则 @supports 规则 tab-size table-layout text-align text-align-last text-decoration text-decoration-color text-decoration-line text-decoration-style text-decoration-thickness text-emphasis text-emphasis-color text-emphasis-position text-emphasis-style text-indent text-justify text-orientation text-overflow text-shadow text-transform text-underline-offset text-underline-position top transform-origin transform-style transition transition-delay transition-duration transition-property transition-timing-function translate unicode-bidi user-select vertical-align visibility white-space widows width word-break word-spacing word-wrap writing-mode z-index zoom 简介 CSS HEX 颜色 HSL 颜色背景图像背景重复背景附着背景简写边框宽度边框颜色边框各边简写边框属性圆角边框外边距合并轮廓宽度轮廓颜色轮廓简写轮廓偏移文本对齐文字装饰文本转换文字间距文本阴影字体样式字体大小谷歌字体字体属性布局 - width 和 max-width 布局 - z-index 布局 - 溢出布局 - clear 和 clearfix 布局 - 浮动实例布局 - display: inline-block 垂直导航栏水平导航栏计数器网站布局特异性 !important 规则数学函数圆角边框图像多重背景颜色颜色关键字渐变径向渐变阴影效果 Box Shadow 文本效果 Web 字体 2D 转换 3D 转换过渡动画工具提示设置图像样式 object-fit object-position 遮罩按钮分页实例多列用户界面变量覆盖变量使用 JavaScript 更改变量在媒体查询中使用变量 @property 规则 Box Sizing Flexbox 媒体查询媒体查询 - 实例 - 简介网格容器网格项目

CSS教程手册

参考手册浏览器支持参考手册选择器参考手册组合器参考手册伪类参考手册伪元素参考手册函数参考手册动画相关属性网络安全字体字体回退单位颜色合法颜色值默认值参考手册实体听觉参考手册

CSS高级

accent-color align-content align-items align-self all animation animation-delay animation-direction animation-duration animation-fill-mode animation-iteration-count animation-name animation-play-state animation-timing-function aspect-ratio backdrop-filter backface-visibility background background-attachment background-blend-mode background-clip background-color background-image background-origin background-position background-position-x background-position-y background-repeat background-size block-size border border-block border-block-color border-block-end border-block-end-color border-block-end-style border-block-end-width border-block-start border-block-start-color border-block-start-style border-block-start-width border-block-style border-block-width border-bottom border-bottom-color border-bottom-left-radius border-bottom-right-radius border-bottom-style border-bottom-width border-collapse border-color border-end-end-radius border-end-start-radius border-image border-image-outset border-image-repeat border-image-slice border-image-source border-image-width border-inline border-inline-color border-inline-end border-inline-end-color border-inline-end-style border-inline-end-width border-inline-start border-inline-start-color border-inline-start-style border-inline-start-width border-inline-style border-inline-width border-left border-left-color border-left-style border-left-width border-radius border-right border-right-color border-right-style border-right-width border-spacing border-start-end-radius border-start-start-radius border-style border-top border-top-color border-top-left-radius border-top-right-radius border-top-style border-top-width border-width bottom box-decoration-break box-reflect box-shadow box-sizing break-after break-before break-inside caption-side caret-color @charset 规则 clear clip clip-path color color-scheme column-count column-fill column-gap column-rule column-rule-color column-rule-style column-rule-width column-span column-width columns @container 规则 content counter-increment counter-reset counter-set @counter-style 规则 cursor direction display empty-cells filter flex flex-basis flex-direction flex-flow flex-grow flex-shrink flex-wrap float font @font-face 规则 font-family font-feature-settings font-kerning @font-palette-values 规则 font-size font-size-adjust font-stretch font-style font-variant font-variant-caps font-weight gap grid grid-area grid-auto-columns grid-auto-flow grid-auto-rows grid-column grid-column-end grid-column-gap grid-column-start grid-gap grid-row grid-row-end grid-row-gap grid-row-start grid-template grid-template-areas grid-template-columns grid-template-rows hanging-punctuation height hyphens hyphenate-character image-rendering @import 规则 initial-letter inline-size inset inset-block inset-block-end inset-block-start inset-inline inset-inline-end inset-inline-start isolation justify-content justify-items justify-self @keyframes 规则 @layer 规则 left letter-spacing line-height list-style list-style-image list-style-position list-style-type margin margin-block margin-block-end margin-block-start margin-bottom margin-inline margin-inline-end margin-inline-start margin-left margin-right margin-top marker marker-end marker-mid marker-start mask mask-clip mask-composite mask-image mask-mode mask-origin mask-position mask-repeat mask-size mask-type max-block-size max-height max-inline-size max-width @media 规则 min-block-size min-inline-size min-height min-width mix-blend-mode @namespace 规则 object-fit object-position offset offset-anchor offset-distance offset-path offset-position offset-rotate opacity order orphans outline outline-color outline-offset outline-style outline-width overflow overflow-anchor overflow-wrap overflow-x overflow-y overscroll-behavior overscroll-behavior-block overscroll-behavior-inline overscroll-behavior-x overscroll-behavior-y padding padding-block padding-block-end padding-block-start padding-bottom padding-inline padding-inline-end padding-inline-start padding-left padding-top @page 规则 page-break-inside paint-order perspective perspective-origin place-content place-items place-self pointer-events position @property 规则 quotes resize right rotate row-gap scale @scope 规则 scroll-behavior scroll-margin scroll-margin-block scroll-margin-block-end scroll-margin-block-start scroll-margin-bottom scroll-margin-inline scroll-margin-inline-end scroll-margin-inline-start scroll-margin-left scroll-margin-right scroll-margin-top scroll-padding scroll-padding-block scroll-padding-block-end scroll-padding-block-start scroll-padding-bottom scroll-padding-inline scroll-padding-inline-end scroll-padding-inline-start scroll-padding-right scroll-padding-top scroll-snap-stop scroll-snap-type scrollbar-color shape-outside @starting-style 规则 @supports 规则 tab-size table-layout text-align text-align-last text-decoration text-decoration-color text-decoration-line text-decoration-style text-decoration-thickness text-emphasis text-emphasis-color text-emphasis-position text-emphasis-style text-indent text-justify text-orientation text-overflow text-shadow text-transform text-underline-offset text-underline-position top transform-origin transform-style transition transition-delay transition-duration transition-property transition-timing-function translate unicode-bidi user-select vertical-align visibility white-space widows width word-break word-spacing word-wrap writing-mode z-index zoom

CSS基础教程

CSS中级教程

布局 - width 和 max-width 布局 - z-index 布局 - 溢出布局 - clear 和 clearfix 布局 - 浮动实例布局 - display: inline-block 垂直导航栏水平导航栏计数器网站布局特异性 !important 规则数学函数

CSS3高级教程

圆角边框图像多重背景颜色颜色关键字渐变径向渐变阴影效果 Box Shadow 文本效果 Web 字体 2D 转换 3D 转换过渡动画工具提示设置图像样式 object-fit object-position 遮罩按钮分页实例多列用户界面变量覆盖变量使用 JavaScript 更改变量在媒体查询中使用变量 @property 规则 Box Sizing Flexbox 媒体查询媒体查询 - 实例

CSS响应式设计

- 简介

CSS网格教程

网格容器网格项目

CSS实例

CSS教程

更新时间2025-07-16

布局 - clear 和 clearfix 布局 - display: inline-block

网格 / 等宽的框

Box 1 Box 2 Box 1 Box 2 Box 3

通过使用 float 属性，可以轻松地并排浮动内容框：

实例

* {
  box-sizing: border-box;
}

.box {
  float: left;
  width: 33.33%; /* 三个框（四框使用 25%，两框使用 50%，以此类推） */
  padding: 50px; /* 如果需要在图片间增加间距 */
}

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什么是 box-sizing？

您可以轻松地并排创建三个浮动框。但是，当您添加一些内容来扩大每个框的宽度（例如，内边距或边框）时，这个框会损坏。 box-sizing 属性允许我们在框的总宽度（和高度）中包括内边距和边框，确保内边距留在框内而不会破裂。

您可以在我们的 CSS Box Sizing 这一章中学习有关 box-sizing 属性的更多知识。

图像并排

这种框格（The grid of boxes）也可以用来并排显示图像：

实例

.img-container {
  float: left;
  width: 33.33%; /* 三个框（四框使用 25%，两框使用 50%，以此类推） */
  padding: 5px; /* 如果需要在图片间增加间距 */
}

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等宽的框

在上例中，您学习了如何以相等的宽度并排浮动框。但是，创建具有相同高度的浮动框并不容易。不过，快速解决方案是设置一个固定的高度，如下例所示：

Box 1

Some content, some content, some content

Box 2

Some content, some content, some content

实例

.box {
  height: 500px;
}

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但是，这么做就失去了弹性。如果可以保证框中始终有相同数量的内容，那是可以的。但是很多时候，内容是不一样的。如果您在手机上尝试上例，则会看到第二个框的内容将显示在框的外部。这是 CSS3 Flexbox 派上用场的地方 - 因为它可以自动拉伸框使其与最长的框一样长：

实例

使用 Flexbox 创建弹性框：

Box 1 - 这是一些文本，以确保内容真的很高。这是一些文本，以确保内容真的很高。这是一些文本，以确保内容真的很高。这是一些文本，以确保内容真的很高。这是一些文本，以确保内容真的很高。 Box 2 - 我的高度将跟随框 1。运行实例 »

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Flexbox 的唯一问题是它在 Internet Explorer 10 或更早版本中不起作用。您可以在我们的 CSS Flexbox 章节中学习有关 Flexbox 布局模块的更多知识。

导航菜单

将 float 与超链接列表一起使用，来创建水平菜单：

实例

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Web 布局实例

使用 float 属性完成整个 Web 布局也很常见：

实例

.header, .footer {
  background-color: grey;
  color: white;
  padding: 15px;
}

.column {
  float: left;
  padding: 15px;
}

.clearfix::after {
  content: "";
  clear: both;
  display: table;
}

.menu {
  width: 25%;
}

.content {
  width: 75%;
}

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所有 CSS 浮动属性

属性	描述
box-sizing	定义元素的宽度和高度的计算方式：它们是否应包含内边距和边框。
clear	指定哪些元素可以在被清除的元素旁边以及在哪一侧浮动。
float	指定元素应如何浮动。
overflow	指定如果内容溢出元素框会发生什么情况。
overflow-x	指定当溢出元素的内容区域时，如何处理内容的左/右边缘。
overflow-y	指定当溢出元素的内容区域时，如何处理内容的上/下边缘。