CSS Grid: media quaries

@media (min-width: 400px){
    .container{
      /* change the code below this line */
    
      grid-template-areas:
        "advert header"
        "advert content"
        "advert footer";

When the viewport width is 400px or more, make the header area occupy the top row completely and the footer area occupy the bottom row completely.

How do you do this, please help

Here, I already explained this:

I’ve edited your post for readability. When you enter a code block into the forum, precede it with a line of three backticks and follow it with a line of three backticks to make easier to read. See this post to find the backtick on your keyboard. The “preformatted text” tool in the editor (</>) will also add backticks around text.

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