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Post-Processing CSS

Vender prefixes are automatically add during build through Autoprefixer.

For example, this:

.App {
  display: flex;
  flex-direction: row;
  align-items: center;
}

becomes this after build:

.App {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: horizontal;
  -webkit-box-direction: normal;
  -ms-flex-direction: row;
  flex-direction: row;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
}

To configure the target browser list, you can adjust the browserslist field in package.json.

Check here for a list of all supported query syntax.