CSS 背景颜色和颜色标签不起作用

Question

I am working on some homework for my HTML class and I believe I am doing what the directions ask but it keeps marking it as wrong. I tried reaching out to the professor and she told me to go read the book but I am doing it exactly as the book says and its wrong. Maybe someone here can spot the issue.

questions: 1: Add a blank line after the CSS reset style rule, add a comment with the text, Style rule for body and image, and then create new style rules for the body and img selectors.

Create a style rule for the body selector that sets a background color value of #e3eaf8. Create a style rule for an img selector that sets a max-width to 100% and displays the images as a block.

2: Add a blank line after the img style rule, add a comment with the text Style rule for header content, and then create a new style rule for the header h1 descendant selector that aligns text center; sets a font size value of 3em; sets a font family value of Georgia, Times, serif; sets a padding value of 3%; and sets a color value of #101a2d.

3: Add a blank line after the header h1 style rule, add a comment with the text Style rules for navigation area, and then create the following style rules for the nav, nav ul, nav li, and nav li a selectors.

Create a style rule for the nav selector that sets the background color to #1d396d. Create a style rule for nav ul that sets the list style type to none, sets the margin to 0, and aligns text center. Create a style rule for nav li that sets the display to an inline-block, sets a font size of 1.5em, sets a font family value of Verdana, Arial, sans-serif, and a font weight value of bold. Create a style rule for nav li a that sets the display to a block, sets a font color value of #e3eaf8, sets top and bottom padding values of 0.5em and left and right padding values of 2em, and removes the text decoration.

Those are the questions and I have tried to change my code a bunch of different ways and I can not seem to get it right

Code:

<DOCTYPE html>
<!--    
    Student Name: Nicholas Prawl
    File Name: styles.css
    Date: 02/13/2021
-->

<!-- 
    CSS Reset
    margin: 0;
    padding: 0;
    border: 0;
-->

<!--
    Style rule for body and image

    body {
      background-color: #e3eaf8;
    }
    img {
      max-width: 100%;
      display: block;
    }
-->

<!--

    Style rule for header content
     header h1 {
      text-align: center;
      font-size: 3em; 
      font-family: Georgia, Times, serif; 
      padding: 3%;
     color: #101a2d;
    }

-->

<!--
    Style rules for navigation area
    nav{
      background-color: #1d396d;
    }
    nav ul{
      list-style-type: none;
      margin: 0;
      text-align: center;
    }
    nav li{
      display: inline-block;
      font-size: 1.5em;
      font-family: Verdana, Arial, sans-serif;
      font-weight: bold;
    }
    nav li a{
      display: block;
      color: #e3eaf8;
      padding-top: 0.5em;
      padding-bottom: 0.5em;
      padding-left: 2em;
      padding-right: 2em;
      text-decoration: none;
  
    }
-->

Answer 1

Many things are wrong with your code.

First, you're adding CSS code inside what I presume to be HTML without using the style tags. Please refer to this article to learn how to properly embed CSS code in HTML:

https://www.w3schools.com/css/css_howto.asp

Also, you're not adding the comments correctly. See how to add comments in CSS code here: https://developer.mozilla.org/en-US/docs/Web/CSS/Comments