The artist posted a close-up photo of herself wearing oversized sunglasses, with her black and green hair styled in a sleek do.
"Your skin looks soo good," one follower commented, while another wrote: "Your hair colour is amazing." A third added: "A stunning image, you look amazing."
VIDEO: Fans go wild for Nicole Kidman's hair transformation
People were just as complimentary about Bella's style too, with many commenting on her leopard print shirt, which she teamed with a leather jacket.
Nicole and Tom adopted Bella and her brother Connor, 25, during their marriage.
Tom Cruise and Nicole Kidman's daughter Bella Cruise shared a cool selfie on social media
Bella and Connor have followed in their dad's footsteps and are both Scientologists, and while they tend to keep out of the spotlight, Nicole previously opened up about her children's beliefs during an interview with Vanity Fair.
She said: "They are adults. They are able to make their own decisions. They have made choices to be Scientologists and as a mother, it’s my job to love them."
The Undoing star continued: "I am an example of that tolerance and that’s what I believe – that no matter what your child does, the child has love and the child has to know there is available love and I’m open here.
Bella lives in London with her husband Max Parker
"I think that’s so important because if that is taken away from a child, to sever that in any child, in any relationship, in any family – I believe it’s wrong. So that’s our job as a parent, to always offer unconditional love."
The doting mum also spoke about Bella living in London, where she resides with her husband Max Parker. "Bella lives just outside London. You know, she really feels more English.
"We lived there for Eyes Wide Shut, Mission Impossible and The Portrait of a Lady. They both had English accents when they were little."
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