Phoenix Reisen Styleguide
Example

Markup
<form>
  <label class="textfield">
    <input type="text" />
    <span class="textfield__label">Name</span>
  </label>
  <label class="radio">
    <input type="radio" name="example" />
    <span class="radio__label">Desktop</span>
  </label>
  <label class="radio">
    <input type="radio" name="example" />
    <span class="radio__label">Mobile</span>
  </label>
  <label class="select">
    <select name="select">
      <option disabled="disabled" selected="selected">Bitte wählen</option>
      <option>MS Amadea</option>
      <option>MS Amera</option>
      <option>MS Artania</option>
      <option>MS Albatros</option>
      <option>MS Deutschland</option>
    </select>
    <span class="select__label" for="select">Lieblingsschiff</span>
  </label>
  <label class="textfield">
    <textarea></textarea>
    <span class="textfield__label">Comments</span>
  </label>
  <label class="checkbox">
    <input type="checkbox" />
    <span class="checkbox__label">Check mich!</span>
  </label>
  <br/>
  <div class="mt3">
    <button type="button" class="btn btn--primary">
      Abschicken
    </button>
    <button type="button" class="btn btn--primary" disabled="disabled">
      <i class="fas fa-spinner fa-spin mr1"></i> Abschicken
    </button>
    <button type="button" class="btn btn--success" disabled="disabled">
      <i class="fas fa-check mr1"></i> Gekauft
    </button>
    <button type="button" class="btn btn--secondary">
      Abbrechen
    </button>
  </div>
  <div class="mt3">
    <button class="btn btn--warning">Löschen</button>
    <button class="btn btn--danger">Alles löschen</button>
    <button class="btn btn--link"><i class="fas fa-home mr1"></i> Home</button>
  </div>
</form>
Source: src/components/_forms.scss, line 1