Coinbase set out in 2012 to make buying bitcoin feel as ordinary as checking a bank balance. The interface that followed is deliberately unexciting: a white canvas, near-black numbers set in tabular figures, a thin portfolio line, and green or red for every price move.

One colour does the persuading. Coinbase Blue, brightened by Moniker's 2021 identity and codified in the open-source Coinbase Design System, marks every Buy, Sell and primary action. Everything else stays quiet, hairline-ruled and regulated-looking.