nature line art, simple line drawing of a flying swallow against a blue background, depicting minimalist nature theme

art line nature simple drawing flying swallow blue background minimalist theme beautiful sketch illustration peaceful serene calm doodle contour design ethereal graceful airy delicate tranquil gentle elegant lustrous organic subtle uncomplicated stylish aesthetic pure harmonious soft wholesome soothing calming tender lovely picturesque easy breezy effortless quiet mild light ai generated