Why circular part is coming up.

Question

Why h1 and background of nav are showing behind circular part. How can I send it behind h1 and nav
https://code.sololearn.com/WqBlAcZcCrom/?ref=app

Answer 1

.main::before{
/* Use z-index */
z-index:-1;
}
It will solve Your Problem

Answer 2

When I use
.main::before{
z-index:-1;
}
Circular part becomes invisible.