Some things to note when using CodePen:
- CodePen does not expect any content outside the
script information must be put in the settings section of the HTML editor.
- You do not need to/cannot link the CSS in your HTML, if you place the CSS in the appropriate section.
- If your project uses React, use the Babel preprocessor, and link the CDN in the appropriate section.
- The editors offer the ability to format and analyze your code, providing useful information about forgotten closing tags etc.
In your specific case, you have a few syntax errors, which are indicated in the syntax highlighting:
It appears you might be using the incorrect quotes
" as well.
If you are still confused with how to use CodePen, please read the official documentation.
Hope this helps