material-web/tabs/lib/_tab.scss

//
// Copyright 2023 Google LLC
// SPDX-License-Identifier: Apache-2.0
//

// go/keep-sorted start
@use 'sass:map';
// go/keep-sorted end
// go/keep-sorted start
@use '../../elevation/elevation';
@use '../../focus/focus-ring';
@use '../../ripple/ripple';
@use '../../sass/string-ext';
@use '../../sass/theme';
@use '../../tokens';
// go/keep-sorted end

@mixin theme($tokens) {
  $reference: tokens.md-comp-tab-values();
  $tokens: theme.validate-theme($reference, $tokens);
  $tokens: theme.create-theme-vars($tokens, '');
  @include theme.emit-theme-vars($tokens);
}

@mixin styles() {
  // contains tokens for all variants and applied where needed
  $tokens: theme.create-theme-vars(tokens.md-comp-tab-values(), '');

  :host {
    // apply primary-tokens by default
    $primary-prefix: 'primary-tab-';
    @each $token, $value in $tokens {
      @if string-ext.has-prefix($token, $primary-prefix) {
        $token: string-ext.trim-prefix(#{$token}, $primary-prefix);
        --_#{$token}: #{$value};
      }
    }

    display: inline-flex;
    outline: none;
    -webkit-tap-highlight-color: transparent;
    vertical-align: middle;

    @include ripple.theme(
      (
        focus-color: var(--_focus-state-layer-color),
        focus-opacity: var(--_focus-state-layer-opacity),
        hover-color: var(--_hover-state-layer-color),
        hover-opacity: var(--_hover-state-layer-opacity),
        pressed-color: var(--_pressed-state-layer-color),
        pressed-opacity: var(--_pressed-state-layer-opacity),
      )
    );

    @include focus-ring.theme(
      (
        shape: 8px,
        offset: -7px,
      )
    );
  }

  .button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    box-sizing: border-box;
    border: none;
    outline: none;
    user-select: none;
    -webkit-appearance: none;
    vertical-align: middle;
    background: transparent;
    text-decoration: none;
    width: 100%;
    position: relative;
    padding: 0;
    margin: 0;
    z-index: 0; // Ensure this is a stacking context so the indicator displays
    font: var(--_label-text-type);
    background-color: var(--_container-color);
    border-bottom: var(--_divider-thickness) solid var(--_divider-color);
    color: var(--_label-text-color);

    &::-moz-focus-inner {
      padding: 0;
      border: 0;
    }
  }

  .button,
  md-ripple {
    border-radius: var(--_container-shape);
  }

  .touch {
    position: absolute;
    top: 50%;
    height: 48px;
    left: 0;
    right: 0;
    transform: translateY(-50%);
  }

  .content {
    position: relative;
    box-sizing: border-box;
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;

    // TODO (b/261201556) replace with spacing token
    $_content-padding: 8px;
    // tabs are naturally sized up to their max height.
    max-height: calc(var(--_container-height) + 2 * $_content-padding);
    padding: $_content-padding;
    gap: 4px;
  }

  .content.inline-icon {
    flex-direction: row;
  }

  .indicator {
    position: absolute;
    box-sizing: border-box;
    z-index: -1;
    transform-origin: bottom left;
    background: var(--_active-indicator-color);
    border-radius: var(--_active-indicator-shape);
    height: var(--_active-indicator-height);
    inset: auto 0 0 0;
    // hidden unless the tab is selected
    opacity: 0;
  }

  // unselected states
  .button ::slotted([slot='icon']) {
    display: inline-flex;
    position: relative;
    writing-mode: horizontal-tb;
    fill: currentColor;
    color: var(--_icon-color);
    font-size: var(--_icon-size);
    width: var(--_icon-size);
    height: var(--_icon-size);
  }

  .button:hover {
    color: var(--_hover-label-text-color);
    cursor: pointer;
  }

  .button:hover ::slotted([slot='icon']) {
    color: var(--_hover-icon-color);
  }

  .button:focus {
    color: var(--_focus-label-text-color);
  }

  .button:focus ::slotted([slot='icon']) {
    color: var(--_focus-icon-color);
  }

  .button:active {
    color: var(--_pressed-label-text-color);
    outline: none;
  }

  .button:active ::slotted([slot='icon']) {
    color: var(--_pressed-icon-color);
  }

  // selected styling
  :host([selected]) .indicator {
    opacity: 1;
  }
  :host([selected]) .button {
    color: var(--_active-label-text-color);
    @include elevation.theme(
      (
        level: var(--_container-elevation),
      )
    );

    @include ripple.theme(
      (
        focus-color: var(--_active-focus-state-layer-color),
        focus-opacity: var(--_active-focus-state-layer-opacity),
        hover-color: var(--_active-hover-state-layer-color),
        hover-opacity: var(--_active-hover-state-layer-opacity),
        pressed-color: var(--_active-pressed-state-layer-color),
        pressed-opacity: var(--_active-pressed-state-layer-opacity),
      )
    );
  }

  :host([selected]) .button ::slotted([slot='icon']) {
    color: var(--_active-icon-color);
  }

  // selected states
  :host([selected]) .button:hover {
    color: var(--_active-hover-label-text-color);
  }

  :host([selected]) .button:hover ::slotted([slot='icon']) {
    color: var(--_active-hover-icon-color);
  }

  :host([selected]) .button:focus {
    color: var(--_active-focus-label-text-color);
  }

  :host([selected]) .button:focus ::slotted([slot='icon']) {
    color: var(--_active-focus-icon-color);
  }

  :host([selected]) .button:active {
    color: var(--_active-pressed-label-text-color);
  }

  :host([selected]) .button:active ::slotted([slot='icon']) {
    color: var(--_active-pressed-icon-color);
  }

  // TODO (b/261201556) implement disabled and high contrast mode
  // styling in beta version.
  // disabled state
  :host([disabled]) {
    cursor: default;
    pointer-events: none;
    // TODO (b/261201556) implement disabled styling in beta version.
    opacity: 0.38;
  }

  // secondary
  :host([variant~='secondary']) {
    // apply secondary-tab tokens
    $secondary-prefix: 'secondary-tab-';
    @each $token, $value in $tokens {
      @if string-ext.has-prefix($token, $secondary-prefix) {
        $token: string-ext.trim-prefix(#{$token}, $secondary-prefix);
        --_#{$token}: #{$value};
      }
    }
  }

  :host([variant~='secondary']) .content {
    width: 100%;
  }

  :host([variant~='secondary']) .indicator {
    min-width: 100%;
  }

  // vertical (no tokens for vertical as yet)
  :host([variant~='vertical']) {
    flex: 0;
  }

  :host([variant~='vertical']) .button {
    width: 100%;
    flex-direction: row;
    border-bottom: none;
    border-right: var(--_divider-thickness) solid var(--_divider-color);
  }

  :host([variant~='vertical']) .content {
    width: 100%;
  }

  :host([variant~='vertical']) .indicator {
    height: 100%;
    min-width: var(--_active-indicator-height);
    inset: 0 0 0 auto;
  }

  :host([variant~='vertical'][variant~='primary']) {
    --_active-indicator-shape: 9999px 0 0 9999px;
  }

  :host,
  ::slotted(*) {
    white-space: nowrap;
  }
}