To add custom CSS to a specific post in WordPress post follow the steps below:
- Open the post
- Then open the browser inspection tool
- Go to the top of the HTML section and look for body tag <body...
- check for the postid-11111 (11111 represent your post id number)
For example: <body class="post-template-default single single-post postid-11111 ingle-format-standard wp-custom-logo ....
- Make sure your custom CSS begins with postid-11111
For example, the custom CSS below will change the background color of paragraphs of only postid-11111 to red.
.postid-11111 p {background-color: red;}