Okay kiddo, so you know there are some girls and women who face challenges in life just because of their gender, right? Well, a long time ago some people realized that this wasn't fair and decided to work towards making things better for girls and women.
State feminism is when the government (that's the people who make the rules and laws for the country) decides to take on this role of making things better for girls and women. The government might create policies or laws that aim to reduce the gender gap or promote equality.
For example, the government might create a law that says girls and boys should have equal access to education. Or they might create policies that make it easier for women to work and have families at the same time.
So basically, state feminism is when the government tries to help girls and women have better opportunities and a more equal life compared to boys and men. It's all about making things fair for everyone!