How to use Lightening scss on page

Hi Hive,

I am trying to replicate the Tree Grid view in my app:
https://www.lightningdesignsystem.com/components/trees/#flavor-grid-deep-nesting

I can see that index.scss is loaded on this page:

User-added image

I cannot add scss file in the component directly like this :
<ltng:require styles="/resource/accHierarchy__SLDS100/scss/components/trees/flavors/base/index.scss" />

I know that this is not the process to add scss.

The output of the component comes without the tree structure as the scss file is not loaded on page:

User-added image