What's wrong with my templating?

I’m having a little trouble understanding why my template is not working. I’m trying to create a jumbotron element specific to each page.

I’ve got base-template-test.php which is a copy of base.php. Then I’ve got in the root folder of my theme base-page-about.php and page-about.php. I’ve also got a templates/page-about.php.

If I select Default template in wordpress dashboard when creating a page, I get a page with the contents from page-about.php. But If I select custom template, I only get the base page.

The template hierarchy will automatically load page-about.php for a page named about. The wrapper will automatically load base-page-about.php when page-about.php is being used.

Because you are manually selecting a custom template (template-custom.php perhaps?) the template hierarchy ignores page-about.php and the wrapper will not know to load base-page-about.php.

Instead the wrapper will try to load base-template-custom.php.

In short, the wrapper takes the file loaded by WordPress and looks for a template with base- prepended.

I was in a bit of a rush when I wrote the above post. I’m used to templating languages from python (like jinja2) and wordpress is pretty much new territory for me. I’m not entirely sure what sort of content I should have in base-page-about.php. There’s only the html for a jumbotron in that file.

Right now, by selecting the default template from dashboard, my about page is an unstyled page with only the raw html. There’s nothing from base-template-custom-php.

Have you read about the template hierarchy and my introduction to the wrapper?
It may help you better understand what and why things go where.