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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

The resource you are linking to is using the 'http' protocol, which may not work when the browser is using https.

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

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.

Vendor Prefixing

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To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="grid">
    <p>Compressed Size: <i class="size">Waiting</i></p>
    <p>Build Time: <i class="time">Waiting</i></p>
    <button class="btn">Compress (Ctrl+Enter)</button>
</div>
<div class="lorem" contenteditable>
    Lorem ipsum dolor sit amet, consectetur adipiscing elit. Praesent sed tristique lacus. Duis leo arcu, auctor in mattis et, accumsan eget nisl. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Morbi venenatis euismod quam, eu rutrum eros pellentesque quis. Integer imperdiet semper dignissim. Integer efficitur nisi at augue tempus porta. In in gravida dui. Sed ac diam erat. Quisque varius mauris vel ipsum blandit, vel congue lectus elementum. Etiam consectetur mi purus, ut semper magna aliquet quis. Nunc congue dignissim est, non malesuada felis aliquet id. Donec at neque ac enim imperdiet convallis. Curabitur tincidunt dapibus metus non tempor. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Phasellus vitae gravida enim. Sed lacinia lacus massa, ac mattis felis accumsan et.

    Integer lobortis sapien quis mi cursus ornare. Mauris lacinia justo eu eleifend ornare. Vivamus efficitur augue vitae nunc euismod, sed feugiat nunc pharetra. Praesent non sem tellus. Donec id felis non purus vulputate feugiat at nec ante. Suspendisse condimentum justo sem, vel vehicula mauris pulvinar id. Phasellus risus ex, venenatis sed bibendum eu, faucibus quis ipsum. Curabitur suscipit quis massa et dignissim. Nunc ac odio mauris. Duis turpis lectus, tempus dapibus ante vel, pharetra malesuada turpis. Aenean feugiat tellus eu mi fringilla, in pulvinar diam vulputate. Mauris lobortis neque eu nibh tempor, eget pharetra massa consectetur. Etiam luctus mauris a ligula convallis tincidunt. Praesent fringilla cursus est, sit amet vehicula dui facilisis et. Mauris a metus elit.

    Vestibulum pellentesque, enim ac vulputate commodo, risus urna ultrices mauris, eget euismod odio libero et eros. Integer faucibus orci sed imperdiet rhoncus. Proin eros eros, ornare ut gravida et, ultrices sed elit. Vestibulum magna neque, lobortis id auctor eu, malesuada non est. Aliquam faucibus a dolor sit amet placerat. Morbi malesuada leo elit. Maecenas tempor dapibus dapibus. Sed ultricies dapibus nisi et rutrum. Vivamus ipsum eros, tincidunt ut enim at, finibus condimentum neque. Nullam sit amet diam eu ipsum tristique sollicitudin. Sed facilisis lectus est, eget mattis erat aliquet et. Cras sed urna volutpat, consequat velit sed, elementum eros. In vel nibh quis sapien mollis fermentum.

    Vestibulum non iaculis velit. Vestibulum fermentum eros non massa dignissim, fermentum feugiat nunc congue. Vestibulum pulvinar augue eget tempus congue. Aliquam maximus elementum diam. Ut sit amet porttitor risus. In hac habitasse platea dictumst. Suspendisse a viverra odio, et hendrerit dolor. Suspendisse nec suscipit nibh.

    Phasellus quis odio ex. Ut pharetra dapibus nisi, et dapibus orci eleifend sed. Aliquam sit amet commodo orci. Duis faucibus, risus quis sagittis finibus, magna nunc accumsan sapien, ac tincidunt mauris odio fermentum ex. Nunc sed justo ipsum. Nullam viverra ante ac lorem facilisis, ac sodales velit iaculis. Donec nec urna ipsum. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Quisque lacinia molestie aliquet. Donec eget felis in leo auctor tincidunt.

    Generated 5 paragraphs, 473 words, 3187 bytes of Lorem Ipsum.</div>
!

CSS 

              
                @media (prefers-color-scheme: dark) {
    :root {
        color-scheme: dark;
    }
}

.grid,
.lorem {
    padding: 10px;
}

.grid {
    display: grid;
    gap: 10px;
    font-variant-numeric: tabular-nums;
    grid-auto-flow: column;
    justify-content: space-around;
}

.lorem {
    border: 1px solid;
    background-color: rgba(255, 255, 255, 0.15);
    padding: 8px 12px;
    margin: 10px;
    resize: both;
    height: 500px;
    overflow: auto;
    scrollbar-gutter: stable;
}
!

JS 

              
                import prettyBytes from "https://cdn.skypack.dev/pretty-bytes?min";
import {
    gzipSync,
    strToU8,
    compress
} from "https://cdn.skypack.dev/fflate?min";

let timeFormatter = new Intl.RelativeTimeFormat("en", {
    style: "narrow",
    numeric: "auto"
});

let content = document.querySelector(".lorem");
let time = document.querySelector(".time");
let size = document.querySelector(".size");

let asyncCompress = (buf, opts = {}) => {
    return new Promise((resolve, reject) => {
        // The default compression method is gzip
        // Increasing mem may increase performance at the cost of memory
        // The mem ranges from 0 to 12, where 4 is the default
        compress(buf, opts, (err, data) => {
            if (err) reject(err);
            resolve(data);
        });
    });
};

let compressFn = () => {
    const startTime = Date.now();
    const buf = strToU8(content.textContent.trim());
    const timeout = setTimeout(() => {
        time.textContent = "Loading...";
        size.textContent = "Loading...";
    }, 100);

    (async () => {
        const data = await asyncCompress(buf, { level: 9 });
        const gzipSize = prettyBytes(data.length);
        clearTimeout(timeout);

        time.textContent = timeFormatter.format(
            (Date.now() - startTime) / 1000,
            "seconds"
        );
        size.textContent = gzipSize;
        console.log(gzipSize);
    })();
};

compressFn();

let button = document.querySelector(".btn");
button.addEventListener("click", compressFn);
document.addEventListener("keydown", (e) => {
    if (e.ctrlKey && e.keyCode === 13) {
        compressFn();
    }
});
!
999px

Console