The showcase images demonstrate the three different styles this can produce.
'Tis wonky. At a weight of 1.0 style2 has a tendency to overpower and replace style1, and sometimes style3. Style3 also has a tendency to overpower style1. I guess that's what can happen when you try to train 3 styles at once! Negative prompting and higher weights can help, as can prompts that indicate a dark background.