Where I work you can wear any hijab colour but the uniform is an abaya or jilbab. I already had a jilbab from Saudi.
The head is an Arabic speaker so I suppose she prefers that dress. I Iove wearing it so I don't mind.
In my last secular workplace, they were all bullies and made me wear a labeled bright red t-shirt or bright blue. It was so horrendous. I used to change into it when I got there, but the hours were too much. Later on, I started wearing a full sleeved black top under it.
I prefer Islamic dress above all, it looks good and it feels good.