Create a breathtaking double exposure portrait featuring a close-up, serene image of a beautiful woman with her hair styled in a loose, messy bun, looking downward with a soft and contemplative expression. Seamlessly blend this portrait with a stunning, vibrant sunset beach scene that appears within the silhouette of her body. The internal scene should depict a woman walking gracefully along the shoreline at sunset, with the warm, glowing colors of the sun reflecting beautifully on the wet sand and the gentle ocean waves. The overall atmosphere should be ethereal, artistic, and tranquil, capturing a perfect harmony between the subject and the vast, colorful horizon.