"Design an adult coloring book page with a focus on thick, bold lines. The image should be in black and white, resembling a traditional coloring page. Employ a realistic art style to depict a serene scene of three Viking men gathered around a crackling campfire. The men are seated on logs, forming a semi-circle. Their intricate Viking attire is adorned with detailed patterns that are characteristic of Norse culture. The fire's warm glow illuminates their rugged features, casting captivating shadows in the process. Each man holds a horn-shaped cup, from which they drink as they exchange animated stories. In the background, towering trees and distant hills help create a sense of depth and isolation. Remember, this is an outline-only image, so focus on delineating the forms of the Vikings, the fire, and the natural elements clearly and boldly. This coloring page should provide a soothing yet engaging experience for adults as they add their personal touch to the scene."