Right now the bestselling title on Amazon US and UK is a colouring book for adults, Secret Garden, created by the illustrator Johanna Basford.
It is called Art Therapy and it seems to give you piece and calm. It is the nostalgia factor, it is the de-stress aspect, it is because the designs of flora and fauna help your creativity without the scary feeling of being in front of a blank sheet.
It is a combination of things that make hordes of adults want something to colour in. Why not try?
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