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HTML

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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

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

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Babel includes JSX processing.

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HTML 

              
                <script src="https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js"></script>

<body>
  <div class="container">
    <nav id="navbar">
      <header><h1 id="header">JS Documentation</h1></header>
      <ul id="nav-list">
        <a class="nav-link" href="#introduction"><li>Introduction</li></a>
        <a class="nav-link" href="#what_you_should_already_know"><li>What you should already know</li></a>
        <a class="nav-link" href="#javascript_and_java"><li>JavaScript and Java</li></a>
        <a class="nav-link" href="#hello_world"><li>Hello World</li></a>
        <a class="nav-link" href="#variables"><li>Variables</li></a>
        <a class="nav-link" href="#declaring_variables"><li>Declaring variables</li></a>
        <a class="nav-link" href="#variable_scope"><li>Variable scope</li></a>
      </ul>
    </nav>
    <main id="main-doc">
      <section class="main-section" id="introduction">
        <header><h2>Introduction</h1></header>
        <div class="section-details">
          <p>JavaScript is a cross-platform, object-oriented scripting language. It is a small and lightweight language. Inside a host environment (for example, a web browser), JavaScript can be connected to the objects of its environment to provide programmatic control over them.</p>
          <p>JavaScript contains a standard library of objects, such as Array, Date, and Math, and a core set of language elements such as operators, control structures, and statements. Core JavaScript can be extended for a variety of purposes by supplementing it with additional objects; for example:</p>
          <ul class="section-list">
            <li>Client-side JavaScript extends the core language by supplying objects to control a browser and its Document Object Model (DOM). For example, client-side extensions allow an application to place elements on an HTML form and respond to user events such as mouse clicks, form input, and page navigation.</li>
            <li>Server-side JavaScript extends the core language by supplying objects relevant to running JavaScript on a server. For example, server-side extensions allow an application to communicate with a database, provide continuity of information from one invocation to another of the application, or perform file manipulations on a server.</li>
          </ul>
        </div>
      </section>
      <section id="what_you_should_already_know" class="main-section">
        <header><h2>What you should already know</h2></header>
        <div class="section-details">
          <p>This guide assumes you have the following basic background:</p>
          <ul class="section-list">
            <li>A general understanding of the Internet and World Wide Web (WWW).</li>
            <li>Good working knowledge on HyperText Markup Language (HTML).</li>
            <li>Some programming experience. If you are new to programming, try one of the tutorials linked on the main page about JavaScript.</li>
          </ul>
        </div>
      </section>
      <section id="javascript_and_java" class="main-section">
        <header><h2>JavaScript and Java</h2></header>
        <div class="section-details">
          <p>JavaScript and Java are similar in some ways but fundamentally different in some others. The JavaScript language resembles Java but does not have Java's static typing and strong type checking. JavaScript follows most Java expression syntax, naming conventions and basic control-flow constructs which was the reason why it was renamed from LiveScript to JavaScript.</p>
          <p>In contrast to Java's compile-time system of classes built by declarations, JavaScript supports a runtime system based on a small number of data types representing numeric, Boolean, and string values. JavaScript has a prototype-based object model instead of the more common class-based object model. The prototype-based model provides dynamic inheritance; that is, what is inherited can vary for individual objects. JavaScript also supports functions without any special declarative requirements. Functions can be properties of objects, executing as loosely typed methods.</p>
          <p>JavaScript is a very free-form language compared to Java. You do not have to declare all variables, classes, and methods. You do not have to be concerned with whether methods are public, private, or protected, and you do not have to implement interfaces. Variables, parameters, and function return types are not explicitly typed.</p>
        </div>
      </section>
      <section class="main-section" id="hello_world">
        <header><h2>Hello World</h2></header>
        <div class="section-details">
          <p>To get started with writing JavaScript, open the Scratchpad and write your first "Hello world" JavaScript code:</p>
          <code>function greetMe(yourName) { alert("Hello " + yourName); }<br>
            greetMe("World");</code>
          <p>Select the code and hit Ctrl+R to watch it unfold in your browser.</p>
        </div>
      </section>
      <section class="main-section" id="variables">  
        <header><h2>Variables</h2></header>
        <div class="section-details">
          <p>You use variables as symbolic names for values in your application. The names of variables, called identifiers, conform to certain rules.</p>
          <p>A JavaScript identifier must start with a letter, underscore (_), or dollar sign ($); subsequent characters can also be digits (0-9). Because JavaScript is case sensitive, letters include the characters "A" through "Z" (uppercase) and the characters "a" through "z" (lowercase).</p>
          <p>You can use ISO 8859-1 or Unicode letters such as å and ü in identifiers. You can also use the Unicode escape sequences as characters in identifiers. Some examples of legal names are Number_hits, temp99, and _name.</p>
        </div>
      </section>
      <section class="main-section" id="declaring_variables">
        <header><h2>Declaring variables</h2></header>
        <div class="section-details">
          <p>You can declare variables in three ways:</p>
          <p>With the keyword var, for example,</p>
          <code>var x = 42;</code>
          <p>This syntax can be used to declare both local and global varibales.</p>
          <p>By simply assigning it a value, for example,</p>
          <code>x = 2;</code>
          <p>This always declares a global variable. It generates a strict javascript warning. Youo should'nt use this variant.</p>
          <p>With the let keyword, for example,</p>
          <code>let y = 13;</code>
          <p>This syntax can be used to declare a block scope variable.</p>
        </div>
      </section>
      <section class="main-section" id="variable_scope">
        <header><h2>Variable scope</h2></header> 
        <div class="section-details">
          <p>When you declare a variable outside of any function, it is called a global variable, because it is available to any other code in the current document. When you declare a variable within a function, it is called a local variable, because it is available only within that function.</p>
          <p>JavaScript before ECMAScript 2015 does not have block statement scope; rather, a variable declared within a block is local to the function (or global scope) that the block resides within. For example the following code will log 5, because the scope of x is the function (or global context) within which x is declared, not the block, which in this case is an if statement.</p>
          <code>if (true) { var x = 5; } console.log(x); // 5</code>
          <p>This behavior changes, when using the let declaration introduced in ECMAScript 2015.</p>
          <code>if (true) { let y = 5; } console.log(y); // ReferenceError: y is not
            defined</code>
        </div>
      </section>
    </main>
  </div>
</body>
!

CSS 

              
                .container{
  margin:0;
  width:100%;
  font-family:sans-serif;
  display:grid;
  grid-template-columns:25% 75%;
  grid-column-gap:4px;
  background:#bbb;
}

#navbar{
  background:white;
}

#main-doc{
  background:white;
}

#doc-heading{
  font-weight:normal;
  font-size:35px;
  margin-left:6%;
}

#navbar ul{
  list-style-type:none;
  padding:0;
}

.nav-link{
  text-decoration:none;
  color:#444;
}

#navbar li{
  padding-left:6%;
  padding-top:12px;
  padding-bottom:12px;
  margin-top:2px;
  margin-bottom:2px;
  font-size:20px;
  border-top:1px solid #aaa;
}

.main-section{
  margin:30px;
}

.main-section h2{
  font-weight:lighter;
  font-size:30px;
}

.section-details{
  padding-left:20px;
  color:#444;
  font-size:15px;
}

.section-details p{
  padding-bottom:8px;
}

.section-details li{
  padding-bottom:14px;
}

code{
  display:block;
  background:#ddd;
  width:90%;
  border-radius:6px;
  padding:20px;
  margin-bottom:6px;
  margin-top:6px;
}

@media only screen and (max-width: 800px){
  .container{
    background:white;
    display:block;
  }
}
!

JS 

              
                // !! IMPORTANT README:

// You may add additional external JS and CSS as needed to complete the project, however the current external resource MUST remain in place for the tests to work. BABEL must also be left in place. 

/***********
INSTRUCTIONS:
  - Select the project you would 
    like to complete from the dropdown 
    menu.
  - Click the "RUN TESTS" button to
    run the tests against the blank 
    pen.
  - Click the "TESTS" button to see 
    the individual test cases. 
    (should all be failing at first)
  - Start coding! As you fulfill each
    test case, you will see them go   
    from red to green.
  - As you start to build out your 
    project, when tests are failing, 
    you should get helpful errors 
    along the way!
    ************/

// PLEASE NOTE: Adding global style rules using the * selector, or by adding rules to body {..} or html {..}, or to all elements within body or html, i.e. h1 {..}, has the potential to pollute the test suite's CSS. Try adding: * { color: red }, for a quick example!

// Once you have read the above messages, you can delete all comments.
!
999px

Console