Tabs page - add scss page

The sample tabs app has a tabs page - but it does not include a scss page.

I have tried adding a scss page with the following:

 page-tabs {
           background: rgba(243,226,199,1);

but it does not apply the css in the tabs page - if I remove the page-tabs { section then the css is applied as a global item.

Any pointers where I am going wrong?