generative ai ethereal autumn silhouette of tree branches set against a colorful pastel sky business concept.

abstract artistic autumn background blurred branches calm composition countryside creative decor decorative design dreamy dusk elegant ethereal foliage gradient harmonious harmony hues idyllic illustrative inspirational landscape mellow misty nature pastel peaceful relaxing scenic seasonal serene silhouette simplicity sky soft soothing subtle sunset tranquil tree vibrant wallpaper