Source: haloed favicon for https://30aguest.com
Primary detected: #0078a8
Key finding
Every scannable candidate at scale ≥ 0.80 sets halo density = 1.0 (full QR pattern through the halo). That single knob makes more difference than anything else once the logo is large — without it, the blanked halo eats too many cells. Interior color density is much more flexible: 0.4–1.0 all scan. Nothing past scale 0.80 verified.