Neon pairs saturation (S) at 90–100% and lightness (L) around 50–65% with a very dark background (roughly 5–12% lightness). The exact same hue on a light background just reads as vivid — it only reads as glowing once it sits against near-black.
The glow itself comes from stacking several blurred box-shadows (or filter: drop-shadow) of the same color at different radii — two or three layers, tight and dense near the shape, spreading and fading outward, is what actually sells a neon-sign look.
It is a staple of cyberpunk, gaming, and nightlife branding, but painting large blocks of body text in neon tires the eye fast. Reserve it for small accents — a button, a badge, a single line of logo — and keep everything else a dark neutral.
When to use
Reserve it for small accents like buttons, badges, or a logo line. Without a dark background, the neon effect simply does not register.