简约风黑白配色盾牌图案圆形方形十字剑条纹插画

minimalist icon design, monochrome black and white color scheme, 16 unique shield icons arranged in 4x4 grid, clean line design, decorative elements of shield outlines and internal lines, no text, pure white background, clear and organized visual effect, conveys simplicity and professionalism, suitable for identification or classification systems