Coloring book page, line work, coloring book design, colouring book style, colouring book for adults, a forest scene, mandala, black and white, thick lines, vector file, high detail adult coloring book page thin black lines white background, 1 bit line art coloring book, only draw outlines, crisp, thick outlines, 2D, flat design, white background –no noise, book, logo, page, letters, words, markers, grayscale, –no black background –ar 4:3 –v 4