Background-color property doesn't work -- need a smarter pair of eyes

I’m starting all over again on the Secret Agent Supply project, and having a nervous breakdown. For some reason I can’t get the background-color property to work anymore. It’s just black text on a white background. To figure out what’s going on, I went back to the beginning with a test HTML:

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Secret Agent Supply Inc.</title>
<!--    <link href="./resources/css/reset.css" type="text/css" rel="stylesheet">-->
    <link href="./resources/css/style.css" type="text/css" rel="stylesheet">
  </head>
  <body>
    <header>
      SECRET AGENT SUPPLY INC.
    </header>
  </body>
</html>



/* STYLESHEET FOR SecretAgentSupply/index */

html {
  font-size: 18px;
}

body {
  color: black;
  font-family: Helvetica, sans-serif;
}

<!-- ------------- -->

header {
  background-color: green;
  height: 60px;
}

I know that I’m doing something stupid, but I just can’t see it. Can someone please help?

<!-- ------------- --> is a html comment, don’t put it in css, use /* comment */ for css

I tried the code myself, it works fine for me following what @stetim94 just said.

Given the html comment is invalid css syntax, the code after the comment has trouble rendering.

So removing the faulty comment will fix the code, which is what i suggested. What value does your reply add to the topic?

I’m just saying that I tried it with what you said, since I wasn’t sure if the comment bit was addedafter (as in, to show that section, etc.)

I knew it was something stupid. Thank you very much.