border box space

when you use border box
example ,
button or div tag and style border

maybe you will write down text

if you want text Paragraph indentation

1. use p tag

          <K-Test>
            <th>
              <p>2K</p>
              <p>Subset</p>
            </th>
          </K-Test>

style

  th {
    border: 1px solid black;
    float: left;
    width: 20rem;
    font-size: 2.5rem;
    background: coral;
    font-weight: bold;

    p {
      justify-content: center;
      text-align: center;
    }
  }

2. div tag

it is simpler than p tag

          <Index>
            K
            <div></div>
            Index
          </Index>