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About CSS Preprocessors
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It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.
About Vendor Prefixing
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We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).
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<p>Notice how the flex items shrink and expand to fill up the entire container on the horizontal row, no matter how the browser is resized.</p>