Bob a bobek omalovanky – geometrická mandala pro dospělé

Black-and-white coloring page illustration of: mandala geometric adult. Audience: adults (relaxation), very simple (toddler) detail, art nouveau drawing style. Pure black outlines on white background, no shading, no fill, no grayscale, no gradient. Closed shapes ready for crayon / marker. Clean printable line-art at high contrast, no watermarks. Wholesome family-friendly imagery only. No graphic content, no scary or violent themes for kids audiences. Specifically: mandala geometric adult. Target search intent (rendered visually, no on-image text): "bob a bobek omalovanky" (cs).