kleen-sign-bg.png in this folder (/Users/brismiles/Downloads/wifisponsor/) at the original 1122 × 1402 px so the QR lands perfectly inside the blank box. After saving, deploy with bash deploy.sh "add kleen sign bg" and reload this page. Open this page from the Kleen Admin → 📋 Bathrooms tab and tap "Print Signs" for the bathrooms you want.
Or pass ?ids=1,2,3 in the URL to print specific ones, or ?all=1 for all registered bathrooms.