Create a single-color decorative ornamental design in the shape of two symmetrical halves of an arch. The ornament should follow the curved silhouette of an open arch, with the left and right sides mirroring each other and leaving the central area completely empty. Fill both halves with an intricate geometric pattern inspired by mountains and traditional ornamental motifs: stylized mountain peaks, angular lines, triangles, diamonds, zigzags, stepped geometric shapes, and repeating decorative elements. The pattern should gradually follow the curvature of the arch and create a harmonious, sophisticated composition. The ornament must be monochrome, with clean, crisp graphic lines and a refined vector-style appearance. Maintain balanced visual density and clear symmetry between both sides. White background, one solid color for the ornament only. No gradients, no shadows, no realistic landscape, no text, no objects, no frame, no additional decorations. Clean contours, precise geometry, elegant ornamental design, high-resolution vector-like graphic.
