Problem with the technical documentation page: please help!

I have virtually done everything right, and have sought help many times, but number 10 userstory keeps failing. What am I doing wrong?

Challenge: Build a Technical Documentation Page

Link to my pen:

Welcom, Theracon.

The answer is given in the error message from the test:

<section id="Reference">
      <header class="heading2">Reference</header>
      <p>
...

That is where your issue is. Take some time reading the requirements and error message. Then, if all else fails, click here:

<section id="Reference" class="main-section">
      <header class="heading2">Reference</header>
      <p>

Hope this helps

It worked! thanks a lot.