1 | # Autoprefixer [![Cult Of Martians][cult-img]][cult]
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2 |
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3 | <img align="right" width="94" height="71"
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4 | src="http://postcss.github.io/autoprefixer/logo.svg"
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5 | title="Autoprefixer logo by Anton Lovchikov">
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6 |
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7 | [PostCSS] plugin to parse CSS and add vendor prefixes to CSS rules using values
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8 | from [Can I Use]. It is [recommended] by Google and used in Twitter and Alibaba.
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9 |
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10 | Write your CSS rules without vendor prefixes (in fact, forget about them
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11 | entirely):
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12 |
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13 | ```css
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14 | ::placeholder {
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15 | color: gray;
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16 | }
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17 |
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18 | .image {
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19 | background-image: url(image@1x.png);
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20 | }
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21 | @media (min-resolution: 2dppx) {
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22 | .image {
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23 | background-image: url(image@2x.png);
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24 | }
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25 | }
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26 | ```
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27 |
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28 | Autoprefixer will use the data based on current browser popularity and property
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29 | support to apply prefixes for you. You can try the [interactive demo]
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30 | of Autoprefixer.
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31 |
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32 | ```css
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33 | ::-moz-placeholder {
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34 | color: gray;
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35 | }
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36 | :-ms-input-placeholder {
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37 | color: gray;
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38 | }
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39 | ::-ms-input-placeholder {
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40 | color: gray;
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41 | }
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42 | ::placeholder {
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43 | color: gray;
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44 | }
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45 |
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46 | .image {
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47 | background-image: url(image@1x.png);
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48 | }
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49 | @media (-webkit-min-device-pixel-ratio: 2),
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50 | (min-resolution: 2dppx) {
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51 | .image {
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52 | background-image: url(image@2x.png);
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53 | }
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54 | }
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55 | ```
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56 |
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57 | Twitter account for news and releases: [@autoprefixer].
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58 |
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59 | <a href="https://evilmartians.com/?utm_source=autoprefixer">
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60 | <img src="https://evilmartians.com/badges/sponsored-by-evil-martians.svg" alt="Sponsored by Evil Martians" width="236" height="54">
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61 | </a>
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62 |
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63 | [interactive demo]: https://autoprefixer.github.io/
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64 | [@autoprefixer]: https://twitter.com/autoprefixer
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65 | [recommended]: https://developers.google.com/web/tools/setup/setup-buildtools#dont_trip_up_with_vendor_prefixes
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66 | [Can I Use]: https://caniuse.com/
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67 | [cult-img]: http://cultofmartians.com/assets/badges/badge.svg
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68 | [PostCSS]: https://github.com/postcss/postcss
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69 | [cult]: http://cultofmartians.com/tasks/autoprefixer-grid.html
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70 |
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71 |
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72 | ## Contents
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73 |
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74 | * [Contents](#contents)
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75 | * [Browsers](#browsers)
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76 | * [FAQ](#faq)
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77 | * [Does Autoprefixer polyfill Grid Layout for IE?](#does-autoprefixer-polyfill-grid-layout-for-ie)
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78 | * [Does it add polyfills?](#does-it-add-polyfills)
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79 | * [Why doesn’t Autoprefixer add prefixes to `border-radius`?](#why-doesnt-autoprefixer-add-prefixes-to-border-radius)
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80 | * [Why does Autoprefixer use unprefixed properties in `@-webkit-keyframes`?](#why-does-autoprefixer-use-unprefixed-properties-in--webkit-keyframes)
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81 | * [How to work with legacy `-webkit-` only code?](#how-to-work-with-legacy--webkit--only-code)
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82 | * [Does Autoprefixer add `-epub-` prefix?](#does-autoprefixer-add--epub--prefix)
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83 | * [Why doesn’t Autoprefixer transform generic font-family `system-ui`?](#why-doesnt-autoprefixer-transform-generic-font-family-system-ui)
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84 | * [Usage](#usage)
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85 | * [Gulp](#gulp)
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86 | * [Webpack](#webpack)
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87 | * [CSS-in-JS](#css-in-js)
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88 | * [CLI](#cli)
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89 | * [Other Build Tools](#other-build-tools)
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90 | * [Preprocessors](#preprocessors)
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91 | * [GUI Tools](#gui-tools)
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92 | * [JavaScript](#javascript)
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93 | * [Text Editors and IDE](#text-editors-and-ide)
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94 | * [Warnings](#warnings)
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95 | * [Disabling](#disabling)
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96 | * [Prefixes](#prefixes)
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97 | * [Features](#features)
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98 | * [Control Comments](#control-comments)
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99 | * [Options](#options)
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100 | * [Environment Variables](#environment-variables)
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101 | * [Using environment variables to support CSS Grid prefixes in Create React App](#using-environment-variables-to-support-css-grid-prefixes-in-create-react-app)
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102 | * [Grid Autoplacement support in IE](#grid-autoplacement-support-in-ie)
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103 | * [Beware of enabling autoplacement in old projects](#beware-of-enabling-autoplacement-in-old-projects)
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104 | * [Autoplacement limitations](#autoplacement-limitations)
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105 | * [Both columns and rows must be defined](#both-columns-and-rows-must-be-defined)
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106 | * [Repeat auto-fit and auto-fill are not supported](#repeat-auto-fit-and-auto-fill-are-not-supported)
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107 | * [No manual cell placement or column/row spans allowed inside an autoplacement grid](#no-manual-cell-placement-or-columnrow-spans-allowed-inside-an-autoplacement-grid)
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108 | * [Do not create `::before` and `::after` pseudo elements](#do-not-create-before-and-after-pseudo-elements)
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109 | * [When changing the `grid gap` value, columns and rows must be re-declared](#when-changing-the-grid-gap-value-columns-and-rows-must-be-re-declared)
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110 | * [Debug](#debug)
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111 | * [Security Contact](#security-contact)
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112 | * [For Enterprise](#for-enterprise)
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113 |
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114 | ## Browsers
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115 |
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116 | Autoprefixer uses [Browserslist], so you can specify the browsers
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117 | you want to target in your project with queries like `> 5%`
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118 | (see [Best Practices]).
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119 |
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120 | The best way to provide browsers is a `.browserslistrc` file in your project
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121 | root, or by adding a `browserslist` key to your `package.json`.
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122 |
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123 | We recommend the use of these options over passing options to Autoprefixer so
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124 | that the config can be shared with other tools such as [babel-preset-env] and
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125 | [Stylelint].
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126 |
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127 | See [Browserslist docs] for queries, browser names, config format, and defaults.
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128 |
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129 | [Browserslist docs]: https://github.com/browserslist/browserslist#queries
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130 | [babel-preset-env]: https://github.com/babel/babel/tree/master/packages/babel-preset-env
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131 | [Best Practices]: https://github.com/browserslist/browserslist#best-practices
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132 | [Browserslist]: https://github.com/browserslist/browserslist
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133 | [Stylelint]: https://stylelint.io/
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134 |
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135 |
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136 | ## FAQ
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137 |
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138 | ### Does Autoprefixer polyfill Grid Layout for IE?
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139 |
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140 | Autoprefixer can be used to translate modern CSS Grid syntax into IE 10
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141 | and IE 11 syntax, but this polyfill will not work in 100% of cases.
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142 | This is why it is disabled by default.
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143 |
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144 | First, you need to enable Grid prefixes by using either the `grid: "autoplace"`
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145 | option or the `/* autoprefixer grid: autoplace */` control comment.
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146 | Also you can use environment variable to enable Grid:
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147 | `AUTOPREFIXER_GRID=autoplace npm build`.
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148 |
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149 | Second, you need to test every fix with Grid in IE. It is not an enable and
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150 | forget feature, but it is still very useful.
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151 | Financial Times and Yandex use it in production.
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152 |
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153 | Third, there is only very limited auto placement support. Read the
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154 | [Grid Autoplacement support in IE](#grid-autoplacement-support-in-ie) section
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155 | for more details.
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156 |
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157 | Fourth, if you are not using the autoplacement feature, the best way
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158 | to use Autoprefixer is by using `grid-template` or `grid-template-areas`.
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159 |
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160 | ```css
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161 | .page {
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162 | display: grid;
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163 | grid-gap: 33px;
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164 | grid-template:
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165 | "head head head" 1fr
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166 | "nav main main" minmax(100px, 1fr)
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167 | "nav foot foot" 2fr /
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168 | 1fr 100px 1fr;
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169 | }
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170 | .page__head {
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171 | grid-area: head;
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172 | }
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173 | .page__nav {
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174 | grid-area: nav;
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175 | }
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176 | .page__main {
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177 | grid-area: main;
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178 | }
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179 | .page__footer {
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180 | grid-area: foot;
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181 | }
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182 | ```
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183 |
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184 | See also:
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185 |
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186 | * [The guide about Grids in IE and Autoprefixer].
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187 | * [`postcss-gap-properties`] to use new `gap` property
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188 | instead of old `grid-gap`.
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189 | * [`postcss-grid-kiss`] has alternate “everything in one property” syntax,
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190 | which makes using Autoprefixer’s Grid translations safer.
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191 |
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192 | [The guide about Grids in IE and Autoprefixer]: https://css-tricks.com/css-grid-in-ie-css-grid-and-the-new-autoprefixer/
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193 | [`postcss-gap-properties`]: https://github.com/jonathantneal/postcss-gap-properties
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194 | [`postcss-grid-kiss`]: https://github.com/sylvainpolletvillard/postcss-grid-kiss
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195 |
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196 |
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197 | ### Does it add polyfills?
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198 |
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199 | No. Autoprefixer only adds prefixes.
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200 |
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201 | Most new CSS features will require client side JavaScript to handle a new
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202 | behavior correctly.
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203 |
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204 | Depending on what you consider to be a “polyfill”, you can take a look at some
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205 | other tools and libraries. If you are just looking for syntax sugar,
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206 | you might take a look at:
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207 |
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208 | - [postcss-preset-env] is a plugins preset with polyfills and Autoprefixer
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209 | to write future CSS today.
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210 | - [Oldie], a PostCSS plugin that handles some IE hacks (opacity, rgba, etc).
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211 | - [postcss-flexbugs-fixes], a PostCSS plugin to fix flexbox issues.
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212 |
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213 | [postcss-flexbugs-fixes]: https://github.com/luisrudge/postcss-flexbugs-fixes
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214 | [postcss-preset-env]: https://github.com/jonathantneal/postcss-preset-env
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215 | [Oldie]: https://github.com/jonathantneal/oldie
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216 |
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217 |
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218 | ### Why doesn’t Autoprefixer add prefixes to `border-radius`?
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219 |
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220 | Developers are often surprised by how few prefixes are required today.
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221 | If Autoprefixer doesn’t add prefixes to your CSS, check if they’re still
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222 | required on [Can I Use].
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223 |
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224 | [Can I Use]: https://caniuse.com/
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225 |
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226 |
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227 | ### Why does Autoprefixer use unprefixed properties in `@-webkit-keyframes`?
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228 |
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229 | Browser teams can remove some prefixes before others, so we try to use all
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230 | combinations of prefixed/unprefixed values.
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231 |
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232 |
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233 | ### How to work with legacy `-webkit-` only code?
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234 |
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235 | Autoprefixer needs unprefixed property to add prefixes. So if you only
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236 | wrote `-webkit-gradient` without W3C’s `gradient`,
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237 | Autoprefixer will not add other prefixes.
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238 |
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239 | But [PostCSS] has plugins to convert CSS to unprefixed state.
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240 | Use [postcss-unprefix] before Autoprefixer.
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241 |
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242 | [postcss-unprefix]: https://github.com/gucong3000/postcss-unprefix
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243 |
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244 |
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245 | ### Does Autoprefixer add `-epub-` prefix?
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246 |
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247 | No, Autoprefixer works only with browsers prefixes from Can I Use.
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248 | But you can use [postcss-epub] for prefixing ePub3 properties.
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249 |
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250 | [postcss-epub]: https://github.com/Rycochet/postcss-epub
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251 |
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252 |
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253 | ### Why doesn’t Autoprefixer transform generic font-family `system-ui`?
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254 |
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255 | `system-ui` is technically not a prefix and the transformation is not
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256 | future-proof. You can use [postcss-font-family-system-ui] to transform
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257 | `system-ui` to a practical font-family list.
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258 |
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259 | [postcss-font-family-system-ui]: https://github.com/JLHwung/postcss-font-family-system-ui
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260 |
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261 |
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262 | ## Usage
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263 |
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264 | ### Gulp
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265 |
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266 | In Gulp you can use [gulp-postcss] with `autoprefixer` npm package.
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267 |
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268 | ```js
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269 | gulp.task('autoprefixer', () => {
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270 | const autoprefixer = require('autoprefixer')
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271 | const sourcemaps = require('gulp-sourcemaps')
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272 | const postcss = require('gulp-postcss')
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273 |
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274 | return gulp.src('./src/*.css')
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275 | .pipe(sourcemaps.init())
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276 | .pipe(postcss([ autoprefixer() ]))
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277 | .pipe(sourcemaps.write('.'))
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278 | .pipe(gulp.dest('./dest'))
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279 | })
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280 | ```
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281 |
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282 | With `gulp-postcss` you also can combine Autoprefixer
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283 | with [other PostCSS plugins].
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284 |
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285 | [gulp-postcss]: https://github.com/postcss/gulp-postcss
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286 | [other PostCSS plugins]: https://github.com/postcss/postcss#plugins
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287 |
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288 |
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289 | ### Webpack
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290 |
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291 | In [webpack] you can use [postcss-loader] with `autoprefixer`
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292 | and [other PostCSS plugins].
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293 |
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294 | ```js
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295 | module.exports = {
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296 | module: {
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297 | rules: [
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298 | {
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299 | test: /\.css$/,
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300 | use: ["style-loader", "css-loader", "postcss-loader"]
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301 | }
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302 | ]
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303 | }
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304 | }
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305 | ```
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306 |
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307 | And create a `postcss.config.js` with:
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308 |
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309 | ```js
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310 | module.exports = {
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311 | plugins: [
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312 | require('autoprefixer')
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313 | ]
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314 | }
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315 | ```
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316 |
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317 | [other PostCSS plugins]: https://github.com/postcss/postcss#plugins
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318 | [postcss-loader]: https://github.com/postcss/postcss-loader
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319 | [webpack]: https://webpack.js.org/
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320 |
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321 |
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322 | ### CSS-in-JS
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323 |
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324 | The best way to use PostCSS with CSS-in-JS is [`astroturf`].
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325 | Add its loader to your `webpack.config.js`:
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326 |
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327 | ```js
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328 | module.exports = {
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329 | module: {
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330 | rules: [
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331 | {
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332 | test: /\.css$/,
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333 | use: ['style-loader', 'postcss-loader'],
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334 | },
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335 | {
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336 | test: /\.jsx?$/,
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337 | use: ['babel-loader', 'astroturf/loader'],
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338 | }
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339 | ]
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340 | }
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341 | }
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342 | ```
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343 |
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344 | Then create `postcss.config.js`:
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345 |
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346 | ```js
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347 | module.exports = {
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348 | plugins: [
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349 | require('autoprefixer')
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350 | ]
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351 | }
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352 | ```
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353 |
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354 | [`astroturf`]: https://github.com/4Catalyzer/astroturf
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355 |
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356 |
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357 | ### CLI
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358 |
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359 | You can use the [postcss-cli] to run Autoprefixer from CLI:
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360 |
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361 | ```sh
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362 | npm install postcss-cli autoprefixer
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363 | npx postcss *.css --use autoprefixer -d build/
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364 | ```
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365 |
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366 | See `postcss -h` for help.
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367 |
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368 | [postcss-cli]: https://github.com/postcss/postcss-cli
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369 |
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370 |
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371 | ### Other Build Tools
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372 |
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373 | * **Grunt:** [grunt-postcss]
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374 | * **Ruby on Rails**: [autoprefixer-rails]
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375 | * **Neutrino**: [neutrino-middleware-postcss]
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376 | * **Jekyll**: add `autoprefixer-rails` and `jekyll-assets` to `Gemfile`
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377 | * **Brunch**: [postcss-brunch]
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378 | * **Broccoli**: [broccoli-postcss]
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379 | * **Middleman**: [middleman-autoprefixer]
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380 | * **Mincer**: add `autoprefixer` npm package and enable it:
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381 | `environment.enable('autoprefixer')`
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382 |
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383 | [neutrino-middleware-postcss]: https://www.npmjs.com/package/neutrino-middleware-postcss
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384 | [middleman-autoprefixer]: https://github.com/middleman/middleman-autoprefixer
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385 | [autoprefixer-rails]: https://github.com/ai/autoprefixer-rails
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386 | [broccoli-postcss]: https://github.com/jeffjewiss/broccoli-postcss
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387 | [postcss-brunch]: https://github.com/iamvdo/postcss-brunch
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388 | [grunt-postcss]: https://github.com/C-Lodder/grunt-postcss
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389 |
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390 |
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391 | #### Preprocessors
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392 |
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393 | * **Less**: [less-plugin-autoprefix]
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394 | * **Stylus**: [autoprefixer-stylus]
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395 | * **Compass**: [autoprefixer-rails#compass]
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396 |
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397 | [less-plugin-autoprefix]: https://github.com/less/less-plugin-autoprefix
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398 | [autoprefixer-stylus]: https://github.com/jenius/autoprefixer-stylus
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399 | [autoprefixer-rails#compass]: https://github.com/ai/autoprefixer-rails#compass
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400 |
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401 |
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402 | #### GUI Tools
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403 |
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404 | * [CodeKit](https://codekitapp.com/help/autoprefixer/)
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405 | * [Prepros](https://prepros.io)
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406 |
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407 |
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408 | ### JavaScript
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409 |
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410 | You can use Autoprefixer with [PostCSS] in your Node.js application
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411 | or if you want to develop an Autoprefixer plugin for a new environment.
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412 |
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413 | ```js
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414 | const autoprefixer = require('autoprefixer')
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415 | const postcss = require('postcss')
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416 |
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417 | postcss([ autoprefixer ]).process(css).then(result => {
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418 | result.warnings().forEach(warn => {
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419 | console.warn(warn.toString())
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420 | })
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421 | console.log(result.css)
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422 | })
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423 | ```
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424 |
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425 | There is also a [standalone build] for the browser or for a non-Node.js runtime.
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426 |
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427 | You can use [html-autoprefixer] to process HTML with inlined CSS.
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428 |
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429 | [html-autoprefixer]: https://github.com/RebelMail/html-autoprefixer
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430 | [standalone build]: https://raw.github.com/ai/autoprefixer-rails/master/vendor/autoprefixer.js
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431 | [PostCSS]: https://github.com/postcss/postcss
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432 |
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433 |
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434 | ### Text Editors and IDE
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435 |
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436 | Autoprefixer should be used in assets build tools. Text editor plugins are not
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437 | a good solution, because prefixes decrease code readability and you will need
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438 | to change values in all prefixed properties.
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439 |
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440 | I recommend you to learn how to use build tools like [Parcel].
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441 | They work much better and will open you a whole new world of useful plugins
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442 | and automation.
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443 |
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444 | If you can’t move to a build tool, you can use text editor plugins:
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445 |
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446 | * [Visual Studio Code](https://github.com/mrmlnc/vscode-autoprefixer)
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447 | * [Atom Editor](https://github.com/sindresorhus/atom-autoprefixer)
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448 | * [Sublime Text](https://github.com/sindresorhus/sublime-autoprefixer)
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449 | * [Brackets](https://github.com/mikaeljorhult/brackets-autoprefixer)
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450 |
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451 | [Parcel]: https://parceljs.org/
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452 |
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453 |
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454 | ## Warnings
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455 |
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456 | Autoprefixer uses the [PostCSS warning API] to warn about really important
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457 | problems in your CSS:
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458 |
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459 | * Old direction syntax in gradients.
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460 | * Old unprefixed `display: box` instead of `display: flex`
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461 | by latest specification version.
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462 |
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463 | You can get warnings from `result.warnings()`:
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464 |
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465 | ```js
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466 | result.warnings().forEach(warn => {
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467 | console.warn(warn.toString())
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468 | })
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469 | ```
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470 |
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471 | Every Autoprefixer runner should display these warnings.
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472 |
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473 | [PostCSS warning API]: http://api.postcss.org/Warning.html
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474 |
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475 |
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476 | ## Disabling
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477 |
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478 | ### Prefixes
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479 |
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480 | Autoprefixer was designed to have no interface – it just works.
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481 | If you need some browser specific hack just write a prefixed property
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482 | after the unprefixed one.
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483 |
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484 | ```css
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485 | a {
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486 | transform: scale(0.5);
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487 | -moz-transform: scale(0.6);
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488 | }
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489 | ```
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490 |
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491 | If some prefixes were generated incorrectly, please create an [issue on GitHub].
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492 |
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493 | [issue on GitHub]: https://github.com/postcss/autoprefixer/issues
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494 |
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495 |
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496 | ### Features
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497 |
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498 | You can use these plugin options to control some of Autoprefixer’s features.
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499 |
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500 | * `grid: "autoplace"` will enable `-ms-` prefixes for Grid Layout including some
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501 | [limited autoplacement support](#grid-autoplacement-support-in-ie).
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502 | * `supports: false` will disable `@supports` parameters prefixing.
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503 | * `flexbox: false` will disable flexbox properties prefixing.
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504 | Or `flexbox: "no-2009"` will add prefixes only for final and IE
|
505 | versions of specification.
|
506 | * `remove: false` will disable cleaning outdated prefixes.
|
507 |
|
508 | You should set them inside the plugin like so:
|
509 |
|
510 | ```js
|
511 | autoprefixer({ grid: 'autoplace' })
|
512 | ```
|
513 |
|
514 |
|
515 | ### Control Comments
|
516 |
|
517 | If you do not need Autoprefixer in some part of your CSS,
|
518 | you can use control comments to disable Autoprefixer.
|
519 |
|
520 | ```css
|
521 | .a {
|
522 | transition: 1s; /* will be prefixed */
|
523 | }
|
524 |
|
525 | .b {
|
526 | /* autoprefixer: off */
|
527 | transition: 1s; /* will not be prefixed */
|
528 | }
|
529 |
|
530 | .c {
|
531 | /* autoprefixer: ignore next */
|
532 | transition: 1s; /* will not be prefixed */
|
533 | mask: url(image.png); /* will be prefixed */
|
534 | }
|
535 | ```
|
536 |
|
537 | There are three types of control comments:
|
538 |
|
539 | * `/* autoprefixer: (on|off) */`: enable/disable all Autoprefixer translations for the
|
540 | whole block both *before* and *after* the comment.
|
541 | * `/* autoprefixer: ignore next */`: disable Autoprefixer only for the next property
|
542 | or next rule selector or at-rule parameters (but not rule/at‑rule body).
|
543 | * `/* autoprefixer grid: (autoplace|no-autoplace|off) */`: control how Autoprefixer handles
|
544 | grid translations for the whole block:
|
545 | * `autoplace`: enable grid translations with autoplacement support.
|
546 | * `no-autoplace`: enable grid translations with autoplacement
|
547 | support *disabled* (alias for deprecated value `on`).
|
548 | * `off`: disable all grid translations.
|
549 |
|
550 | You can also use comments recursively:
|
551 |
|
552 | ```css
|
553 | /* autoprefixer: off */
|
554 | @supports (transition: all) {
|
555 | /* autoprefixer: on */
|
556 | a {
|
557 | /* autoprefixer: off */
|
558 | }
|
559 | }
|
560 | ```
|
561 |
|
562 | Note that comments that disable the whole block should not be featured in the same
|
563 | block twice:
|
564 |
|
565 | ```css
|
566 | /* How not to use block level control comments */
|
567 |
|
568 | .do-not-do-this {
|
569 | /* autoprefixer: off */
|
570 | transition: 1s;
|
571 | /* autoprefixer: on */
|
572 | transform: rotate(20deg);
|
573 | }
|
574 | ```
|
575 |
|
576 |
|
577 | ## Options
|
578 |
|
579 | Function `autoprefixer(options)` returns a new PostCSS plugin.
|
580 | See [PostCSS API] for plugin usage documentation.
|
581 |
|
582 | ```js
|
583 | autoprefixer({ cascade: false })
|
584 | ```
|
585 |
|
586 | Available options are:
|
587 |
|
588 | * `env` (string): environment for Browserslist.
|
589 | * `cascade` (boolean): should Autoprefixer use Visual Cascade,
|
590 | if CSS is uncompressed. Default: `true`
|
591 | * `add` (boolean): should Autoprefixer add prefixes. Default is `true`.
|
592 | * `remove` (boolean): should Autoprefixer [remove outdated] prefixes.
|
593 | Default is `true`.
|
594 | * `supports` (boolean): should Autoprefixer add prefixes for `@supports`
|
595 | parameters. Default is `true`.
|
596 | * `flexbox` (boolean|string): should Autoprefixer add prefixes for flexbox
|
597 | properties. With `"no-2009"` value Autoprefixer will add prefixes only
|
598 | for final and IE 10 versions of specification. Default is `true`.
|
599 | * `grid` (false|`"autoplace"`|`"no-autoplace"`): should Autoprefixer
|
600 | add IE 10-11 prefixes for Grid Layout properties?
|
601 | * `false` (default): prevent Autoprefixer from outputting
|
602 | CSS Grid translations.
|
603 | * `"autoplace"`: enable Autoprefixer grid translations
|
604 | and *include* autoplacement support. You can also use
|
605 | `/* autoprefixer grid: autoplace */` in your CSS.
|
606 | * `"no-autoplace"`: enable Autoprefixer grid translations
|
607 | but *exclude* autoplacement support. You can also use
|
608 | `/* autoprefixer grid: no-autoplace */` in your CSS.
|
609 | (alias for the deprecated `true` value)
|
610 | * `stats` (object): custom [usage statistics] for `> 10% in my stats`
|
611 | browsers query.
|
612 | * `overrideBrowserslist` (array): list of queries for target browsers.
|
613 | Try to not use it. The best practice is to use `.browserslistrc` config
|
614 | or `browserslist` key in `package.json` to share target browsers
|
615 | with Babel, ESLint and Stylelint. See [Browserslist docs]
|
616 | for available queries and default value.
|
617 | * `ignoreUnknownVersions` (boolean): do not raise error on unknown browser
|
618 | version in Browserslist config. Default is `false`.
|
619 |
|
620 | Plugin object has `info()` method for debugging purpose.
|
621 |
|
622 | You can use PostCSS processor to process several CSS files
|
623 | to increase performance.
|
624 |
|
625 | [usage statistics]: https://github.com/browserslist/browserslist#custom-usage-data
|
626 | [PostCSS API]: http://api.postcss.org
|
627 |
|
628 | ## Environment Variables
|
629 |
|
630 | * `AUTOPREFIXER_GRID`: (`autoplace`|`no-autoplace`) should Autoprefixer
|
631 | add IE 10-11 prefixes for Grid Layout properties?
|
632 | * `autoplace`: enable Autoprefixer grid translations
|
633 | and *include* autoplacement support.
|
634 | * `no-autoplace`: enable Autoprefixer grid translations
|
635 | but *exclude* autoplacement support.
|
636 |
|
637 | Environment variables are useful, when you want to change Autoprefixer options but don't have access to config files.
|
638 | [Create React App] is a good example of this.
|
639 |
|
640 | [Create React App]: (https://reactjs.org/docs/create-a-new-react-app.html#create-react-app)
|
641 |
|
642 | ### Using environment variables to support CSS Grid prefixes in Create React App
|
643 |
|
644 | 1. Install the latest version of Autoprefixer and [cross-env](https://www.npmjs.com/package/cross-env):
|
645 |
|
646 | ```
|
647 | npm install autoprefixer@latest cross-env --save-dev
|
648 | ```
|
649 |
|
650 | 2. Under `"browserslist"` > `"development"` in the package.json file, add `"last 1 ie version"`
|
651 |
|
652 | ```
|
653 | "browserslist": {
|
654 | "production": [
|
655 | ">0.2%",
|
656 | "not dead",
|
657 | "not op_mini all"
|
658 | ],
|
659 | "development": [
|
660 | "last 1 chrome version",
|
661 | "last 1 firefox version",
|
662 | "last 1 safari version",
|
663 | "last 1 ie version"
|
664 | ]
|
665 | }
|
666 | ```
|
667 |
|
668 | 3. Update `"scripts"` in the package.json file to the following:
|
669 |
|
670 | ```
|
671 | "scripts": {
|
672 | "start": "cross-env AUTOPREFIXER_GRID=autoplace react-scripts start",
|
673 | "build": "cross-env AUTOPREFIXER_GRID=autoplace react-scripts build",
|
674 | "test": "cross-env AUTOPREFIXER_GRID=autoplace react-scripts test",
|
675 | "eject": "react-scripts eject"
|
676 | },
|
677 | ```
|
678 |
|
679 | Replace `autoplace` with `no-autoplace` in the above example if you prefer to disable Autoprefixer Grid autoplacement support.
|
680 |
|
681 | Now when you run `npm start` you will see CSS Grid prefixes automatically being applied to your output CSS.
|
682 |
|
683 | See also [Browserslist environment variables] for more examples on how to use environment variables in your project.
|
684 |
|
685 | [Browserslist environment variables]: https://github.com/browserslist/browserslist#environment-variables
|
686 |
|
687 | ## Grid Autoplacement support in IE
|
688 |
|
689 | If the `grid` option is set to `"autoplace"`, limited autoplacement support is added to Autoprefixers grid translations. You can also use
|
690 | the `/* autoprefixer grid: autoplace */` control comment or
|
691 | `AUTOPREFIXER_GRID=autoplace npm build` environment variable.
|
692 |
|
693 | Autoprefixer will only autoplace grid cells if both `grid-template-rows`
|
694 | and `grid-template-columns` has been set. If `grid-template`
|
695 | or `grid-template-areas` has been set, Autoprefixer will use area based
|
696 | cell placement instead.
|
697 |
|
698 | Autoprefixer supports autoplacement by using `nth-child` CSS selectors.
|
699 | It creates [number of columns] x [number of rows] `nth-child` selectors.
|
700 | For this reason Autoplacement is only supported within the explicit grid.
|
701 |
|
702 | ```css
|
703 | /* Input CSS */
|
704 |
|
705 | /* autoprefixer grid: autoplace */
|
706 |
|
707 | .autoplacement-example {
|
708 | display: grid;
|
709 | grid-template-columns: 1fr 1fr;
|
710 | grid-template-rows: auto auto;
|
711 | grid-gap: 20px;
|
712 | }
|
713 | ```
|
714 |
|
715 | ```css
|
716 | /* Output CSS */
|
717 |
|
718 | /* autoprefixer grid: autoplace */
|
719 |
|
720 | .autoplacement-example {
|
721 | display: -ms-grid;
|
722 | display: grid;
|
723 | -ms-grid-columns: 1fr 20px 1fr;
|
724 | grid-template-columns: 1fr 1fr;
|
725 | -ms-grid-rows: auto 20px auto;
|
726 | grid-template-rows: auto auto;
|
727 | grid-gap: 20px;
|
728 | }
|
729 |
|
730 | .autoplacement-example > *:nth-child(1) {
|
731 | -ms-grid-row: 1;
|
732 | -ms-grid-column: 1;
|
733 | }
|
734 |
|
735 | .autoplacement-example > *:nth-child(2) {
|
736 | -ms-grid-row: 1;
|
737 | -ms-grid-column: 3;
|
738 | }
|
739 |
|
740 | .autoplacement-example > *:nth-child(3) {
|
741 | -ms-grid-row: 3;
|
742 | -ms-grid-column: 1;
|
743 | }
|
744 |
|
745 | .autoplacement-example > *:nth-child(4) {
|
746 | -ms-grid-row: 3;
|
747 | -ms-grid-column: 3;
|
748 | }
|
749 | ```
|
750 |
|
751 | ### Beware of enabling autoplacement in old projects
|
752 |
|
753 | Be careful about enabling autoplacement in any already established projects that have
|
754 | previously not used Autoprefixer's grid autoplacement feature before.
|
755 |
|
756 | If this was your html:
|
757 |
|
758 | ```html
|
759 | <div class="grid">
|
760 | <div class="grid-cell"></div>
|
761 | </div>
|
762 | ```
|
763 |
|
764 | The following CSS will not work as expected with the autoplacement feature enabled:
|
765 |
|
766 | ```css
|
767 | /* Unsafe CSS when Autoplacement is enabled */
|
768 |
|
769 | .grid-cell {
|
770 | grid-column: 2;
|
771 | grid-row: 2;
|
772 | }
|
773 |
|
774 | .grid {
|
775 | display: grid;
|
776 | grid-template-columns: repeat(3, 1fr);
|
777 | grid-template-rows: repeat(3, 1fr);
|
778 | }
|
779 | ```
|
780 |
|
781 | Swapping the rules around will not fix the issue either:
|
782 |
|
783 | ```css
|
784 | /* Also unsafe to use this CSS */
|
785 |
|
786 | .grid {
|
787 | display: grid;
|
788 | grid-template-columns: repeat(3, 1fr);
|
789 | grid-template-rows: repeat(3, 1fr);
|
790 | }
|
791 |
|
792 | .grid-cell {
|
793 | grid-column: 2;
|
794 | grid-row: 2;
|
795 | }
|
796 | ```
|
797 |
|
798 | One way to deal with this issue is to disable autoplacement in the
|
799 | grid-declaration rule:
|
800 |
|
801 | ```css
|
802 | /* Disable autoplacement to fix the issue */
|
803 |
|
804 | .grid {
|
805 | /* autoprefixer grid: no-autoplace */
|
806 | display: grid;
|
807 | grid-template-columns: repeat(3, 1fr);
|
808 | grid-template-rows: repeat(3, 1fr);
|
809 | }
|
810 |
|
811 | .grid-cell {
|
812 | grid-column: 2;
|
813 | grid-row: 2;
|
814 | }
|
815 | ```
|
816 |
|
817 | The absolute best way to integrate autoplacement into already existing projects
|
818 | though is to leave autoplacement turned off by default and then use a control
|
819 | comment to enable it when needed. This method is far less likely to cause
|
820 | something on the site to break.
|
821 |
|
822 | ```css
|
823 | /* Disable autoplacement by default in old projects */
|
824 | /* autoprefixer grid: no-autoplace */
|
825 |
|
826 | /* Old code will function the same way it always has */
|
827 | .old-grid {
|
828 | display: grid;
|
829 | grid-template-columns: repeat(3, 1fr);
|
830 | grid-template-rows: repeat(3, 1fr);
|
831 | }
|
832 | .old-grid-cell {
|
833 | grid-column: 2;
|
834 | grid-row: 2;
|
835 | }
|
836 |
|
837 | /* Enable autoplacement when you want to use it in new code */
|
838 | .new-autoplace-friendly-grid {
|
839 | /* autoprefixer grid: autoplace */
|
840 | display: grid;
|
841 | grid-template-columns: repeat(3, 1fr);
|
842 | grid-template-rows: repeat(3, auto);
|
843 | }
|
844 | ```
|
845 |
|
846 | Note that the `grid: "no-autoplace"` setting and the
|
847 | `/* autoprefixer grid: no-autoplace */` control comment share identical
|
848 | functionality to the `grid: true` setting and the `/* autoprefixer grid: on */`
|
849 | control comment. There is no need to refactor old code to use `no-autoplace`
|
850 | in place of the old `true` and `on` statements.
|
851 |
|
852 | ### Autoplacement limitations
|
853 |
|
854 | #### Both columns and rows must be defined
|
855 |
|
856 | Autoplacement only works inside the explicit grid. The columns and rows need to be defined
|
857 | so that Autoprefixer knows how many `nth-child` selectors to generate.
|
858 |
|
859 | ```css
|
860 | .not-allowed {
|
861 | display: grid;
|
862 | grid-template-columns: repeat(3, 1fr);
|
863 | }
|
864 |
|
865 | .is-allowed {
|
866 | display: grid;
|
867 | grid-template-columns: repeat(3, 1fr);
|
868 | grid-template-rows: repeat(10, auto);
|
869 | }
|
870 | ```
|
871 |
|
872 | #### Repeat auto-fit and auto-fill are not supported
|
873 |
|
874 | The `repeat(auto-fit, ...)` and `repeat(auto-fill, ...)` grid functionality relies on
|
875 | knowledge from the browser about screen dimensions and the number of available grid
|
876 | items for it to work properly. Autoprefixer does not have access to this information
|
877 | so unfortunately this little snippet will _never_ be IE friendly.
|
878 |
|
879 | ```css
|
880 | .grid {
|
881 | /* This will never be IE friendly */
|
882 | grid-template-columns: repeat(auto-fit, min-max(200px, 1fr))
|
883 | }
|
884 | ```
|
885 |
|
886 | #### No manual cell placement or column/row spans allowed inside an autoplacement grid
|
887 |
|
888 | Elements must not be manually placed or given column/row spans inside
|
889 | an autoplacement grid. Only the most basic of autoplacement grids are supported.
|
890 | Grid cells can still be placed manually outside the the explicit grid though.
|
891 | Support for manually placing individual grid cells inside an explicit
|
892 | autoplacement grid is planned for a future release.
|
893 |
|
894 | ```css
|
895 | .autoplacement-grid {
|
896 | display: grid;
|
897 | grid-template-columns: repeat(3, 1fr);
|
898 | grid-template-rows: repeat(3, auto);
|
899 | }
|
900 |
|
901 | /* Grid cells placed inside the explicit grid
|
902 | will break the layout in IE */
|
903 | .not-permitted-grid-cell {
|
904 | grid-column: 1;
|
905 | grid-row: 1;
|
906 | }
|
907 |
|
908 | /* Grid cells placed outside the
|
909 | explicit grid will work in IE */
|
910 | .permitted-grid-cell {
|
911 | grid-column: 1 / span 2;
|
912 | grid-row: 4;
|
913 | }
|
914 | ```
|
915 |
|
916 | If manual cell placement is required, we recommend using `grid-template` or
|
917 | `grid-template-areas` instead:
|
918 |
|
919 | ```css
|
920 | .page {
|
921 | display: grid;
|
922 | grid-gap: 30px;
|
923 | grid-template:
|
924 | "head head"
|
925 | "nav main" minmax(100px, 1fr)
|
926 | "foot foot" /
|
927 | 200px 1fr;
|
928 | }
|
929 | .page__head {
|
930 | grid-area: head;
|
931 | }
|
932 | .page__nav {
|
933 | grid-area: nav;
|
934 | }
|
935 | .page__main {
|
936 | grid-area: main;
|
937 | }
|
938 | .page__footer {
|
939 | grid-area: foot;
|
940 | }
|
941 | ```
|
942 |
|
943 | #### Do not create `::before` and `::after` pseudo elements
|
944 |
|
945 | Let's say you have this HTML:
|
946 |
|
947 | ```html
|
948 | <div class="grid">
|
949 | <div class="grid-cell"></div>
|
950 | </div>
|
951 | ```
|
952 |
|
953 | And you write this CSS:
|
954 |
|
955 | ```css
|
956 | .grid {
|
957 | display: grid;
|
958 | grid-template-columns: 1fr 1fr;
|
959 | grid-template-rows: auto;
|
960 | }
|
961 |
|
962 | .grid::before {
|
963 | content: 'before';
|
964 | }
|
965 |
|
966 | .grid::after {
|
967 | content: 'after';
|
968 | }
|
969 | ```
|
970 |
|
971 | This will be the output:
|
972 |
|
973 | ```css
|
974 | .grid {
|
975 | display: -ms-grid;
|
976 | display: grid;
|
977 | -ms-grid-columns: 1fr 1fr;
|
978 | grid-template-columns: 1fr 1fr;
|
979 | -ms-grid-rows: auto;
|
980 | grid-template-rows: auto;
|
981 | }
|
982 |
|
983 | .grid > *:nth-child(1) {
|
984 | -ms-grid-row: 1;
|
985 | -ms-grid-column: 1;
|
986 | }
|
987 |
|
988 |
|
989 | .grid > *:nth-child(2) {
|
990 | -ms-grid-row: 1;
|
991 | -ms-grid-column: 2;
|
992 | }
|
993 |
|
994 | .grid::before {
|
995 | content: 'before';
|
996 | }
|
997 |
|
998 | .grid::after {
|
999 | content: 'after';
|
1000 | }
|
1001 | ```
|
1002 |
|
1003 | IE will place `.grid-cell`, `::before` and `::after` in row 1 column 1.
|
1004 | Modern browsers on the other hand will place `::before` in row 1 column 1,
|
1005 | `.grid-cell` in row 1 column 2, and `::after` in row 2 column 1.
|
1006 |
|
1007 | See this [Code Pen](https://codepen.io/daniel-tonon/pen/gBymVw) to see a visualization
|
1008 | of the issue. View the Code Pen in both a modern browser and IE to see the difference.
|
1009 |
|
1010 | Note that you can still create `::before` and `::after` elements as long as you manually
|
1011 | place them outside the explicit grid.
|
1012 |
|
1013 | #### When changing the `grid gap` value, columns and rows must be re-declared
|
1014 |
|
1015 | If you wish to change the size of a `grid-gap`, you will need to redeclare the grid columns and rows.
|
1016 |
|
1017 | ```css
|
1018 | .grid {
|
1019 | display: grid;
|
1020 | grid-template-columns: 1fr 1fr;
|
1021 | grid-template-rows: auto;
|
1022 | grid-gap: 50px;
|
1023 | }
|
1024 |
|
1025 | /* This will *NOT* work in IE */
|
1026 | @media (max-width: 600px) {
|
1027 | .grid {
|
1028 | grid-gap: 20px;
|
1029 | }
|
1030 | }
|
1031 |
|
1032 | /* This will *NOT* work in IE */
|
1033 | .grid.small-gap {
|
1034 | grid-gap: 20px;
|
1035 | }
|
1036 | ```
|
1037 |
|
1038 | ```css
|
1039 | .grid {
|
1040 | display: grid;
|
1041 | grid-template-columns: 1fr 1fr;
|
1042 | grid-template-rows: auto;
|
1043 | grid-gap: 50px;
|
1044 | }
|
1045 |
|
1046 | /* This *WILL* work in IE */
|
1047 | @media (max-width: 600px) {
|
1048 | .grid {
|
1049 | grid-template-columns: 1fr 1fr;
|
1050 | grid-template-rows: auto;
|
1051 | grid-gap: 20px;
|
1052 | }
|
1053 | }
|
1054 |
|
1055 | /* This *WILL* work in IE */
|
1056 | .grid.small-gap {
|
1057 | grid-template-columns: 1fr 1fr;
|
1058 | grid-template-rows: auto;
|
1059 | grid-gap: 20px;
|
1060 | }
|
1061 | ```
|
1062 |
|
1063 | ## Debug
|
1064 |
|
1065 | Run `npx autoprefixer --info` in your project directory to check
|
1066 | which browsers are selected and which properties will be prefixed:
|
1067 |
|
1068 | ```
|
1069 | $ npx autoprefixer --info
|
1070 | Browsers:
|
1071 | Edge: 16
|
1072 |
|
1073 | These browsers account for 0.26% of all users globally
|
1074 |
|
1075 | At-Rules:
|
1076 | @viewport: ms
|
1077 |
|
1078 | Selectors:
|
1079 | ::placeholder: ms
|
1080 |
|
1081 | Properties:
|
1082 | appearance: webkit
|
1083 | flow-from: ms
|
1084 | flow-into: ms
|
1085 | hyphens: ms
|
1086 | overscroll-behavior: ms
|
1087 | region-fragment: ms
|
1088 | scroll-snap-coordinate: ms
|
1089 | scroll-snap-destination: ms
|
1090 | scroll-snap-points-x: ms
|
1091 | scroll-snap-points-y: ms
|
1092 | scroll-snap-type: ms
|
1093 | text-size-adjust: ms
|
1094 | text-spacing: ms
|
1095 | user-select: ms
|
1096 | ```
|
1097 |
|
1098 | JS API is also available:
|
1099 |
|
1100 | ```js
|
1101 | console.log(autoprefixer().info())
|
1102 | ```
|
1103 |
|
1104 | ## Security Contact
|
1105 |
|
1106 | To report a security vulnerability, please use the [Tidelift security contact].
|
1107 | Tidelift will coordinate the fix and disclosure.
|
1108 |
|
1109 | [Tidelift security contact]: https://tidelift.com/security
|
1110 |
|
1111 | ## For Enterprise
|
1112 |
|
1113 | Available as part of the Tidelift Subscription.
|
1114 |
|
1115 | The maintainers of `autoprefixer` and thousands of other packages are working
|
1116 | with Tidelift to deliver commercial support and maintenance for the open source
|
1117 | dependencies you use to build your applications. Save time, reduce risk,
|
1118 | and improve code health, while paying the maintainers of the exact dependencies
|
1119 | you use. [Learn more.](https://tidelift.com/subscription/pkg/npm-autoprefixer?utm_source=npm-autoprefixer&utm_medium=referral&utm_campaign=enterprise&utm_term=repo)
|