Bat-Signal
#feff00
High-contrast lightning yellow, warmer than Canary gray
About Bat-Signal
Bat-Signal sits at that sweet spot where yellow stops trying to prove itself. It's got the lift of Bee Yellow's glow but trades the soft landing for actual edge, there's a sharpness here that the others avoid, a color that lands and stays put. Not warm, not cool, just committed.
This is the yellow for dark interfaces, alerts that need to cut through, and product highlights where gentleness would feel like indecision. Notification badges. Focus states on dark backgrounds. Marketing layouts that need punch without the neon shriek of Canary. It's lighter than Big Yellow Taxi but less forgiving, pair it with anything and it doesn't settle, it announces. Dashboards where the aesthetic can handle a little tension. Design tools where you're building for contrast first.
The thing: use it sparingly. This one doesn't disappear into the background like Bee Yellow or soften into a system player like Big Yellow Taxi. It's the color you reach for when you need yellow to actually work, not just exist. Against cool grays it sharpens further, which is usually the point.
Code snippets
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Contrast checker
WCAG 2.1 contrast ratios. AA requires 4.5:1 for normal text, 3:1 for large. AAA requires 7:1 / 4.5:1.
On White #ffffff
On Gray 100 #f5f5f5
On Gray 900 #18181b
On Black #000000
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