At full width both rows fit and nothing is faded. Make the frame narrower until they overflow. The first row fades at both edges. The second fades only the side that still has content: sharp at the start, then fading there too once you scroll.
.scroller
Overview
Payments
Balances
Customers
Products
Reports
Billing
Developers
Settings
.scroller-edges
Overview
Payments
Balances
Customers
Products
Reports
Billing
Developers
Settings