Vintage travel poster illustration of Khao Yai National Park, Thailand, retro WPA flat color block style, 5-color limited palette using deep forest green, burnt sienna, cream white, dark navy blue, and warm ochre, bold graphic silhouettes of jungle-covered mountains, cascading waterfall, and tropical forest silhouettes, dramatic layered landscape with foreground, midground, and background planes, art deco geometric sensibility, hard crisp edges with absolutely no gradients or blending, screen-print texture, aged matte paper finish, 1930s–1950s American national park poster aesthetic, vertical portrait orientation, reserved blank banner areas at top and bottom for title text, high contrast composition, timeless iconic graphic style