Sky Fantasy Book Cover Design (Evoking wonder, mysterious, and magical)

Visuals: Silhouetted figures of four kids stand on a grassy hill in the foreground. They gaze upon a magnificent medieval town bathed in twilight, with a towering, enchanted castle at the center, glowing softly under the moonlight. Wisps of fog lap at the edges of the town, and stars scattered throughout the deep, rich blue sky add a sense of wonder and mystery.

Typography: The book title, "once upon a time," is in an elegant serif font, with subtle ornate detailing that echoes the fantasy genre. The author's name, "Keren Zetino Monteros," is in a complementary sans-serif font to provide a modern touch.

Layout: The book title arches across the top portion of the cover, with the children's silhouettes just beneath it, directing attention toward the scene. The author's name is positioned at the bottom in a balanced, centered format. Delicate flourishes of light weave through and around the title and author name.

Explanation: The visual composition sets the tone for a fantasy journey by placing readers in the shoes of the young characters, staring into a world filled with magical elements. The use of silhouettes for the kids keeps their identities ambiguous, enhancing the viewer's curiosity and wonder about their adventure. The castle, gleaming under moonlight, stands as a beacon of mystery and magic, which is central to the genre. The typography choice of an elegant serif font with ornate touches aligns with traditional fairy tales, while the sans-serif author's name adds readability and balance. The premium matte finish enhances the mysterious allure of the design, while the spot gloss highlights key features, making them pop against the softer background, thereby immersing potential readers in a world of magic and mystery.