@vaadin/vaadin-lumo-styles/src/mixins/field-required.css

Lumo is a design system foundation for modern web applications, used by Vaadin components

/**
 * @license
 * Copyright (c) 2017 - 2026 Vaadin Ltd.
 * This program is available under Apache License Version 2.0, available at https://vaadin.com/license/
 */
@media lumo_mixins_field-required {
  :host([required]) [part='required-indicator']::after {
    content: var(--vaadin-input-field-required-indicator, var(--lumo-required-field-indicator, '\2022'));
    color: var(
      --vaadin-input-field-required-indicator-color,
      var(--lumo-required-field-indicator-color, var(--lumo-primary-text-color))
    );
    position: absolute;
    right: 0;
    width: 1em;
    text-align: center;
  }

  :host([invalid]) [part='required-indicator']::after {
    color: var(
      --vaadin-input-field-required-indicator-color,
      var(--lumo-required-field-indicator-color, var(--lumo-error-text-color))
    );
  }

  /* RTL specific styles */

  :host([dir='rtl']) [part='required-indicator']::after {
    right: auto;
    left: 0;
  }
}