You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Marvel_Comics

Context:
Lee and freelance artist and eventual co-plotter Jack Kirby's Fantastic Four originated in a Cold War culture that led their creators to revise the superhero conventions of previous eras to better reflect the psychological spirit of their age. Eschewing such comic-book tropes as secret identities and even costumes at first, having a monster as one of the heroes, and having its characters bicker and complain in what was later called a "superheroes in the real world" approach, the series represented a change that proved to be a great success.

Question:
The emphasis on relatable settings and character motivations in Marvel's 1960s comics is called what?

"superheroes in the real world"