Wow! You really should enter this in the street art challenge! It really is different! I haven't seen one above the head. And your composition with the welcome sign is so clever!
I guess it makes you feel like you're under the sea. Great artwork. We did see something like this in an underpass in Italy last year. It went from the railway station to the town
https://365project.org/discuss/themes-competitions/47608/street-art-2-keep-your-eyes-open-for-murals-and-graffiti!