Media Query Documentation Project

Hello I am having trouble getting my media query to work. Could someone tell me where I’m running into issues?

nav #navbar {
    position: fixed;
    top: 50px;
    left: 50px;
  }

main {
  height: 100vh;
}

.main-section {
  height: 50vh;
}

@media screen and(min-width: 400px) {
  .main-section {
    background-color: blue;
  }
}

Thanks!

Hi.
For question like this sometimes more context needed.
There may be issue in Your HTML file, not only in CSS, for example.
And also consider to provide link to the task.