Insure landing page challenge hub

Hello , this is my first time using calc(), i found it in a video on youtube and i was trying to use on my project, it's useful, but i'll try to do my best in the future using it. *Second, I don't know why my boton view plans doesn't work when i'm try using css, i think i've done something wrong. *Third, The upper right spirals do not overlap in the image, i try to add the z-index, but it did not work

Any feedback is welcome!