<!DOCTYPE html>
<html>
  <head>
    <style>
      p {
        padding: 10px;
        border-style: solid
      }
      p.one {
        border-width: thin; /* 1px */
      }
      p.two {
        border-width: medium; /* 3px */
      }
      p.three {
        border-width: thick; /* 5px */
      }
      p.four {
        border-width: 15px;
      }
    </style>
  </head>
  <body>
    <h2>border-width Property</h2>

    <p>initial: 3px</p>
    <p class="one">thin: 1px</p>
    <p class="two">medium: 3px</p>
    <p class="three">thick: 5px</p>
    <p class="four">15px</p>
  </body>
</html>

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