Thanks for reaching out. I’ve replied to your email. Everything looks good in your style.css file. Did you include a functions.php file in your child theme? The parent style.css file is enqueued from the child functions.php file, perhaps that was the problem.
I’ve follow your guide from email. I’ve install your attached ultra-child.zip from Appearance > Themes > Add New > Upload Theme, and success activated.
The result is my home page still not fixed. Look at this screenshot. What should I do now?