Create a complete portrait front cover for this fictional cozy mystery. Book title: THE LAST LANTERN. Author: MARA VALE. Subtitle: A COASTAL MYSTERY. Small tagline: A MYSTERY AT THE WATER’S EDGE. Story: A retired mapmaker returns to a quiet harbor town after its old lantern keeper disappears. Each evening, one warm light reveals a clue along the waterfront. Use a midnight-blue and muted-teal harbor with an amber lantern, a quiet lighthouse and restrained illustrated details. Set the exact title and author clearly, with a strong reading order at thumbnail size. Keep the cover focused on this one story; include no other book or author names. Produce the complete front-cover design with artwork and typography.