Design a motivational fitness-themed T-shirt featuring the phrase "NO PAIN NO GAIN" in bold, stylized text at the top and bottom. At the center, illustrate a strong, muscular arm gripping a large dumbbell to emphasize strength and determination. Surround the arm and dumbbell with radiating lines to create a sense of energy and intensity. Use a monochromatic color scheme with shades of black and beige for a bold and striking appearance. This design should evoke a sense of perseverance and hard work, perfect for fitness enthusiasts and bodybuilders.