@vaadin/vaadin-lumo-styles/mixins/required-field.js

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/
 */
import { issueWarning } from '@vaadin/component-base/src/warnings.js';
import { css, registerStyles } from '@vaadin/vaadin-themable-mixin/vaadin-themable-mixin.js';

issueWarning('Lumo .js mixins are deprecated and will be removed in V26');

const requiredField = css`
  [part='label'] {
    align-self: flex-start;
    color: var(--vaadin-input-field-label-color, var(--lumo-secondary-text-color));
    font-weight: var(--vaadin-input-field-label-font-weight, 500);
    font-size: var(--vaadin-input-field-label-font-size, var(--lumo-font-size-s));
    transition: color 0.2s;
    line-height: 1;
    padding-inline: calc(var(--lumo-border-radius-m) / 4) 1em;
    padding-bottom: 0.5em;
    /* As a workaround for diacritics being cut off, add a top padding and a
    negative margin to compensate */
    padding-top: 0.25em;
    margin-top: -0.25em;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    position: relative;
    max-width: 100%;
    box-sizing: border-box;
  }

  :host([focused]:not([readonly])) [part='label'] {
    color: var(--vaadin-input-field-focused-label-color, var(--lumo-primary-text-color));
  }

  :host(:hover:not([readonly]):not([focused])) [part='label'] {
    color: var(--vaadin-input-field-hovered-label-color, var(--lumo-body-text-color));
  }

  /* Touch device adjustment */
  @media (pointer: coarse) {
    :host(:hover:not([readonly]):not([focused])) [part='label'] {
      color: var(--vaadin-input-field-label-color, var(--lumo-secondary-text-color));
    }
  }

  :host([has-label])::before {
    margin-top: calc(var(--lumo-font-size-s) * 1.5);
  }

  :host([has-label][theme~='small'])::before {
    margin-top: calc(var(--lumo-font-size-xs) * 1.5);
  }

  :host([has-label]) {
    padding-top: var(--lumo-space-m);
  }

  :host([has-label]) ::slotted([slot='tooltip']) {
    --vaadin-tooltip-offset-bottom: calc((var(--lumo-space-m) - var(--lumo-space-xs)) * -1);
  }

  :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))
    );
  }

  [part='error-message'] {
    margin-left: calc(var(--lumo-border-radius-m) / 4);
    font-size: var(--vaadin-input-field-error-font-size, var(--lumo-font-size-xs));
    line-height: var(--lumo-line-height-xs);
    font-weight: var(--vaadin-input-field-error-font-weight, 400);
    color: var(--vaadin-input-field-error-color, var(--lumo-error-text-color));
    will-change: max-height;
    transition: 0.4s max-height;
    max-height: 5em;
  }

  :host([has-error-message]) [part='error-message']::before,
  :host([has-error-message]) [part='error-message']::after {
    content: '';
    display: block;
    height: 0.4em;
  }

  :host(:not([invalid])) [part='error-message'] {
    max-height: 0;
    overflow: hidden;
  }

  /* RTL specific styles */

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

  :host([dir='rtl']) [part='error-message'] {
    margin-left: 0;
    margin-right: calc(var(--lumo-border-radius-m) / 4);
  }
`;

registerStyles('', requiredField, { moduleId: 'lumo-required-field' });

export { requiredField };