In most cases, it's the color you say. That's caused by people's fat. But urine is yellow and is caused by urea.
This problem is easy to understand when you know that stool (feces) is unabsorbed food residue.
Generally, normal feces are brown, because feces contain fecal bile pigment and urobilin. Due to different foods, feces have also changed. For example, the feces rich in food in protein are smelly, slightly hard, lumpy, slightly yellowish brown or yellowish in color, and most of them contain Gram-positive bacteria; Feces that eat carbohydrate-rich foods are brown-green, smelly, soft or semi-liquid, acidic, and most bacteria are gram-negative. Some drugs can also change the color of feces.
In addition, the stool is alkaline, and its alkalinity is related to the length of stay in the colon. The longer the residence time, the higher the alkalinity. On the contrary, thin feces have a short retention time and are often acidic, which can stimulate the skin around the anus. This is why we are in a hurry to leave the hospital with a stomachache, and the "molding rate" is very low.
I hope it helps you.