Technical Document Error

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When I run the test on codepen, it passes 15/16. I can’t seem to find where I went wrong. This is the part that is not passing.

10. Additionally, the navbar should contain link (<a>) elements with the class of “nav-link”. There should be one for every element with the class “main-section”.

Your code so far

HTML Guide
<a class="nav-link" href="#Creating_Your_First_Webpage" rel="internal">
  <li>Creating Your First Webpage</li>
<a class="nav-link" href="#How_To_Add_Headings" rel="internal">
  <li>How To Add Headings</li>
<a class="nav-link" href="#How_To_Add_Text" rel="internal">
  <li>How To Add Text</li>
<a class="nav-link" href="#How_To_Add_Images" rel="internal">
  <li>How To Add Images</li>
<a class="nav-link" href="#How_To_Close_a_Document" rel="internal">
  <li>How To Close a Document</li>
<a class="nav-link" href="#Reference" rel="internal">
<article id="intro">
  <p>HTML stands for Hyper Text Markup Language. HTML is the language that is used to build most websites. To make the websites more visually pleasing, CSS would be used.</p>
  <p> In this guide you will learn a few basics to get started with the HTML code language. The sections include:
      <li>Tags and Attributes</li>
      <li>Creating your first webpage</li>
      <li>How to add headings</li>
      <li>How to add text</li>
      <li>How to add images</li>
      <li>How to close a document</li>
    <p><strong>Note:</strong> This is only a basic reference guide. It is best to take courses from a reputable program such as <a class="hyperlink" href="">freecodecamp</a> to become more comfortable with the language.</p>
<header>Tags and Attributes</header>
<article id="tags">
  <p>Tags are used in HTML to mark the start of an element. Tags are usually enclosed in angle brackets like this
  <p>When additional information needs to be added to a tag this is called the attribute. If you look below, you will find an example where the (src) and (alt) are the attributes of the img tag.</p>
  <p> <code>< img src="cat.jpg" alt="Cat Picture" ></code></p>
<header>Creating Your First Webpage</header>
<article id="firstpage">
  <p>Before getting started, find a reliable HTML editor and open to a blank page. The first bit of code that needs to be entered is <strong>< !DOCTYPE html ></strong>and underneath you would add <strong>< HTML ></strong>. This tells the program that
    you will be writing in HTML language.</p>
  <p>The following example shows the basic layout to begin creating a webpage.</p>
  <p><code> < !DOCTYPE html ><br><br>< HTML ><br><br>< head >Information in this tag is mainly for search engines. It is not meant to be for visitors to see.< /head ><br><br>< title >This is where to title of the webpage goes.< /title ><br><br>< body >This is where the information meant for visitors to see is placed.< /body ></code></p>
<header>How To Add Headings</header>
<article id="headings">
  <p>Heading tags, in HTML, are how you add headlines to your webpage. There are six different heading tags.</p>
      < h1>
      < h2>
      < h3>
      < h4>
      < h5>
      < h6>
  <p>These tags are in order of importance and will be read that way in search engines.</p>
<header>How To Add Text</header>
<article id="texts">
  <p>When creating a new paragraph of text in HTML, you would use the <strong>< p ></strong> tag. The appearance of the text can be changed by using the following tags.</p>
    <li><b>< b ></b>- Bold text</li>
    <li><b>< strong ></b>- Important text</li>
    <li><b>< i ></b>- Italic text</li>
    <li><b>< em ></b>- Emphasized text</li>
    <li><b>< mark ></b>- Marked text</li>
    <li><b>< small ></b>- Small text</li>
    <li><b>< del ></b>- Deleted text</li>
    <li><b>< ins ></b>- Inserted text</li>
    <li><b>< sub ></b>- Subscript text</li>
    <li><b>< sup ></b>- Superscript text</li>
  <p>Make sure to have an open and close tag for each of these.</p>
<header>How To Add Images</header>
<article id="images">
  <p>To make a webpage visually pleasing, you may consider adding images. This can be accomplished by using the <strong>< img ></strong> tag. The attributes added in this tag are <strong>(src) , (alt) , (height) , (width)</strong>. The <strong>(alt)</strong>        attribute describes the image for search engines and the visually impaired.</p>
  <p>Here is an example of the <strong>< img ></strong> tag in use.</p>
  <code>< img src="cat.jpg" alt="Cat Picture" height="50" width="50" ></code>
  <p>In this example, the image would use it's original size.</p>
  <code>< img src="cat.jpg" alt="Cat Picture" ></code>
<header>How To Close a Document</header>
<article id="closing">
  <p>When you are done with creating your HTML web document, you need to make sure to add the correct closing tags. The closing tags for the document should look like this:</p>
  <code>< /body ><br>< /html ></code>
  <p>Remember that these are just the basics to building a webpage using HTML language. It takes a lot of practice and time to become comfortable with coding of any type.</p>
<article id="refer">
  <p>The information in this guide was collected through <a class="hyperlink" href=""> </a>and <a class="hyperlink" href="">Freecodecamp</a>.</p>

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Nevermind I figured it out