Design high-resolution train illustrations suitable for a children's coloring book to be published on Amazon KDP. The guidelines are:Ensure optimal resolution for clear and sharp printing.Illustrate various types of trains: steam trains, electric trains, cargo trains, high-speed trains, trams, etc.Scenes should be simple yet engaging, such as a train passing through the countryside, one at a station with children watching, or a train winding through mountains.While we want details, ensure they are spaced out enough for children to color with ease and without frustration.Incorporate additional elements to make coloring more enjoyable: animals peeking out from windows, birds flying nearby, or quaint little stations.Adhere to the printing dimensions and guidelines set by Amazon KDP.The goal is to captivate children's imaginations while providing them with a delightful, varied train-centric coloring experience."