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HTML

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About the <head>

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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HTML 

              
                <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="index.css">
    <title>Media Queries</title>
</head>
<body>
     <h1>Making Responsive Websites</h1>
     <p><em>Media queries</em> are a great way to ensure that all users of a website have a 
    good experience. The media queries - literally '@media' as if it's asking the 
    media a question - will ask the browser of a user about it's current dimensions. 
    The browser will tell our CSS what size it is, and the CSS will rearrange and
    re-display based on those parameters. My goal here is to show how to use the 
    queries, but all we want from you right this instant is awareness that the 
    concept of media queries exists. This stuff is going on in the background of
    things like Bootstrap.</p>
</body>
</html>
!

CSS 

              
                @media only screen and (min-width: 600px) {
    body {
        background-color: aquamarine;
        display: flex;
        flex-direction: row;
    }
}

@media only screen and (min-width: 800px) {
    body {
        background-color: red;
        font-family: Arial, Helvetica, sans-serif;
    }
}

@media only screen and (min-width: 1000px) {
    body {
        background-color: coral;
        font-family: Impact, Haettenschweiler, 'Arial Narrow Bold', sans-serif;
        display: flex;
        flex-direction: column;
    }
}

@media only screen and (min-width: 1200px) {
    body {
        background-color: salmon;
        font-family: Georgia, 'Times New Roman', Times, serif;
    }
}
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JS
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999px

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