drupalcampbristol/web/modules/contrib/webform/css/webform.element.file.button.css

/**
 * @file
 * File upload button styles.
 *
 * @see https://stackoverflow.com/questions/21842274/cross-browser-custom-styling-for-file-upload-button
 */
.webform-file-button-input {
  position: fixed;
  top: -1000px;
}