为了让图像更加生动，你可以添加一些钢铁色的齿轮。 你首先需要定义渐变色（多层渐变色，灰色和绿色阴影）。 使用渐变色填充齿轮。 将钢铁色齿轮放置在设备中（注意不要让钢铁齿轮与黄金齿轮咬合，因为只有相同颜色齿轮才能咬合）。 将转轴放置在齿轮中心。 绘制一些固定设备用的螺丝。 将螺丝均匀放置（如果你喜欢，也可以随机放置），作品就完成了！

Given the above summary, write a detailed text in English for it.
Here is one trick to get some of the wheels richer, not that plain and boring: add a groove - two smaller circles, aligned to the center of the gear, filled with the same grey gradient, the larger in an opposite direction, the smaller in the same direction as the rest of the wheel. steel with steel and gold with gold). Now for some axles: small circles, made from gold, steel, ruby or sapphire. Do not forget the drop shadow and consider a white highlight.  They are easy to do: create a steel circle, subtract a rectangle to create the groove, add a darker steel rectangle, the bottom of the groove, rotate the screw to a random angle (we don't want all the screws to have parallel grooves, that would be repeating and boring), fix the gradient and add a drop shadow. Maybe a hole: a larger circle colored with the same gradient as the background but with an opposed orientation. (I increased the zoom level in this step for a clearer illustration)