Design a pixel art t-shirt featuring a stylized gemstone at the center, rendered in a vibrant electric blue color with a strong, bold outline (2-3 pixels) for clarity. Surround the gemstone with 8-bit-inspired terrain elements such as pixelated rocks, stylized trees, and vines, arranged in a balanced manner to create a cohesive composition. Use earthy tones (greens, browns, grays) for the terrain elements to complement the gemstone. Incorporate a few scattered pixels around the design to enhance the retro gaming feel, using a mix of colors that harmonize with the main elements. The final design should be saved in a high-resolution PNG format with a transparent background, allowing the wearer's clothing to shine through. Consider adding a slight glow effect around the gemstone to enhance its vibrancy and draw attention.