Learn the CSS Box Model by Building a Rothko Painting - Step 13

Tell us what’s happening:
Describe your issue in detail here.

I don’t understand the description for the step 13.
In the pervious step, it asked us to set the “border: 50px solid black” but the border is too big and can’t wrap around the “canvas”.
Therefore, on step 13, it asks us to change the width= 500px.
Isn’t it widen the border even further away from canvas? << this is what I want to ask.
Thank you for the help.

Your code so far

/* file: styles.css */
.canvas {
  width: 500px;
  height: 600px;
  background-color: #4d0f00;
}

.frame {
  border: 50px solid black;

}
<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Rothko Painting</title>
    <link href="./styles.css" rel="stylesheet">
  </head>
  <body>
    <div class="frame">
      <div class="canvas">
      </div>
    </div>
  </body>
</html>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Challenge: Learn the CSS Box Model by Building a Rothko Painting - Step 13

Link to the challenge:

I just come up some idea:
“border: 50px solid black;” is indicated:
border-width: 50px;
border-style: solid;
border-color: black;

Therefore, “width: 500px;” is talking about the space inside the border, like the space from border-left to border-right.
Am I on the right track?

Thank you.