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HTML

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About the <head>

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Insecure Resource

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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 

              
                <header class="site-header">
  <div class="site-title">
    A Serverless Blog
  </div>
  <div class="site-subtitle">
    All the code that powers this blog is right here. 
  </div>
</header>

<main class="site-wrap">

  <div id="articles-list">
    <div class="articles-container" />
  </div>

</main>
!

CSS 

              
                * {
  box-sizing: border-box;
}

.site-header {
  border-top: 1rem solid #556CF6;
  background: #26232d;
  padding: 2rem;
  position: relative;
}
.site-title {
  font-size: 2rem;
  letter-spacing: 3px;
}
.site-subtitle {
  font-style: italic;
  opacity: 0.5;
}
.sign-in-button {
  position: absolute;
  top: 1rem;
  right: 1rem;
}

.site-wrap {
  padding: 2rem;
}

.article-block {
  max-width: 650px;
  margin: 0 auto 2rem;
  background: #403E4F;
  padding: 2rem;
  box-shadow: 0.25rem 0.25rem 1.3rem rgba(0, 0, 0, 0.33);
}
time {
  display: block;
  padding: 0.25rem 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.25rem;
  background: linear-gradient(
    to right,
    #4a4c5a,
    #403E4D
  );
  font-size: 0.75rem;
}
.article-body {
  color: #9e9fa8;
}

.article-whole {
  max-width: 850px;
  margin: 0 auto;
}


body {
  margin: 0;
  background: #323041;
  color: white;
  font-family: 'PT Serif', serif;
  line-height: 1.4;
}
h1, h2, h3, h4, h5, h6,
.site-title {
  font-family: 'Barlow Semi Condensed', sans-serif;
  text-transform: uppercase;
}
h1, h2, h3, h4, h5, h6 {
  margin: 0 0 1rem 0;
  letter-spacing: 0.1rem;
  line-height: 1;
}
h1 {
  font-size: 3.0rem;
  letter-spacing: 0.1rem;
}
a {
  color: #8b9bff;
  font-weight: bold;
  border-bottom: 1px solid;
  text-decoration: none;
  padding: 0.25rem 0.5rem;  
}
a svg {
  fill: currentcolor;
  vertical-align: bottom;
}
a:hover,
a:focus {
  background: rgba(0, 0, 0, 0.33);
}
!

JS 

              
                var blog_api_url = 'https://us-central1-duncan-131.cloudfunctions.net/posts';
var posts_list = document.getElementById('articles-list');
var posts_container = posts_list.querySelector('.articles-container');

var loadJsonFromFirebase = function(url, callback) {
    var xhr = new XMLHttpRequest();
    xhr.addEventListener("load", function () {
        callback(JSON.parse(this.response));
    });
    xhr.open("GET", url);
    xhr.send();
};

loadJsonFromFirebase(blog_api_url, function(data) {
  let list = document.createElement('div');
  Object.keys(data).forEach(function(key) {
    let ts = new Date(data[key].created);
    list.innerHTML += `<article class="article-block">
      <h2>${data[key].title}</h2>
      <time>${ts.toDateString()}</time>
      <div class="excerpt">
        <p>${data[key].content.substr(0, 150)}...</p>
      </div>
      <a href="#${key}" data-post="${key}">Read Post</a>
    </article>`;
  });
  posts_container.insertBefore(list, posts_container.firstChild);
});
!
999px

Console