Alpha-store-child does not save changes

Did you enable the child-theme? When using child-themes you should enable the child instead of its parent.

However when I make changes in browser, they disappear when the website reloads.

Are you using the inspector of your browser? When making changes in there, you should also apply these in your css file via FTP ( which is located at get_template_directory_uri() . '/style.css').

The inspector can only change things locally!

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)