## Styles

The markup page references an external stylesheet document.

    <!DOCTYPE html>
    <html>
      <head>
        <title>Our Solar System</title>
        <!-- the link element is used to reference a stylesheet -->
        <link rel="stylesheet" href="styles/solarsystem.css" />

The CSS file contains style rules for the document (solarsystem.css)

Contents of the CSS file:

    body {
      margin-left: 5%;
      margin-top: 2rem;
      margin-right: 5%;
      background-image: linear-gradient(#ffffff, #ffffef);
      background-color: #ffffdd;
      font-family: Calibri, Arial, sans-serif;
      min-height: 100vh;
    }

    h1 {
      font-family: Calibri, Arial, sans-serif;
      color: #333333;
      border-bottom: 3px solid #333333;
    }

    ul.gallery {
      list-style: none;
      padding: 0;
      margin: 0;
      display: flex;
      flex-wrap: wrap;
      justify-content: flex-start;
    }

    ul.gallery li {
      font-size: 1.25rem;
      flex-basis: 1 0 auto;
      text-align: center;
      border: thin dotted #333333;
      margin: 0.8rem;
      padding: 0.8rem;
    }

    ul.gallery li img {
      border: none;
    }

    footer {
      margin-top: 2rem;
      padding: 1rem;
      font-size: smaller;
    }

    a:link, a:visited {
      text-decoration: none;
      color: blue;
    }

    a:hover {
      text-decoration: underline;
    }

    a:active {
      border: none;
      text-decoration: none;
    }