Style a Bootstrap 4 Checkbox without label

I'm trying to style a Bootstrap 4 checkbox without a label:

<div class="form-check">
    <input class="form-check-input position-static" type="checkbox" id="blankCheckbox" value="option1">
</div>

My trial and error styles:

  .form-check {
      .form-check-input {
        color: #2c2b2c;
        font-size: 12px;
        line-height: 2.7;
        padding-left:15px;
        text-transform: uppercase;
        background-color: red;
      }
      .form-check-input::after,
      .form-check-input::before {
        height: 25px;
        width: 25px;
      }
      .form-check-input::before {
        background-color: #fff;
        border: 1px solid #2c2b2c;
      }
    }
  }

I'm able to style the label version, but unsuccessful with this version.