Harmony and relaxation with Coloring-for-Adults.com: Coloring page Serious panda – modern online coloring by numbers and book for download and print for adults. Paint the picture in accordance with your spiritual aspiration, forget about the rules for combining colors. Save present and future results as a keepsake. come back get inspired! Permission: Creative Commons Attribution-NonCommercial 4.0 License. Artist: Persimmons Studio.