堆肥白板动画

Hand-drawn cut-away side view of one wooden compost bin made of horizontal planks, with the front cut open to show three clear layers inside: the top layer is fresh green and colourful kitchen scraps (lettuce leaves, a banana peel, apple cores, carrot tops); the middle layer is brown, half-rotted leaves and scraps breaking down; the bottom layer is dark, crumbly black soil. Exactly two pink earthworms wriggle inside the layers. Only the bin, the three layers and the two worms. Nothing else in the picture, plenty of empty space around the bin. Coloured pencil and watercolour marker, clean black ink outlines, warm off-white paper, no text.