Neptune

I keep circling back to Neptune when the UI needs that clean, saturated blue without tipping into the teal lean of Jacuzzi. It reads a touch more assertive and steadier than Bleu Ciel, but it doesn't feel as bright or "sky-open" as Mediterranean Blue. The undertone stays cool, with a firmer middle depth that holds its shape on real screens.

For actual work, I use it for primary CTAs and selected states in productivity SaaS, logistics portals, and customer support consoles where the emphasis needs to be obvious in a busy layout. It's also a solid choice for data-heavy fintech pages and internal admin apps, especially when you want dashboards and finance apps energy without the warmer friendliness that Jacuzzi can bring. I reach for Neptune as the one I reach for when hierarchy must land fast and stay consistent.

Pair it with neutral grays or crisp whites. Side-by-side with very teal-adjacent blues, Neptune stays cleaner and more "blue-first," so the distinction doesn't blur.