What is license of a combined/derived image from CC0 sources?

I have a couple of images which are CC0 licensed. But I want to combine these images and create a new image and use it in a commercial project. Are CC0 licensed images allowed to modified and used in a commercial project?

Image 1 is this.
Image 2 is this.

After I combine both images in Photoshop it becomes this.

Images are taken from Pixabay. You can look at Pixabay terms of use here.