I have this code:

```
<html>
    <head>
      <title>Document Title</title>
    </head>
    <body>
      <div style="border:1px solid black;"
           style="background-color: green !important;">
        Test Text
      </div>
    </body>
</html>

```

The border exists as specified. However, the background of the div is not green. Why is the background of the div not green?

I know this is basic, but I've been reading for hours and I can't find an answer anywhere.