<fieldset>
  <legend>Choose your monster's features:</legend>

  <div>
    <input type="checkbox" id="scales" name="scales" checked />
    <label for="scales">Scales</label>
  </div>

  <div>
    <input type="checkbox" id="horns" name="horns" />
    <label for="horns">Horns</label>
  </div>
</fieldset>

p,
label {
  font:
    1rem 'Fira Sans',
    sans-serif;
}

input {
  margin: 0.4rem;
}