material-components_material-web/button/internal/_icon.scss

//
// Copyright 2021 Google LLC
// SPDX-License-Identifier: Apache-2.0
//

@mixin styles() {
  // The icon CSS class overrides styles defined in the .material-icons CSS
  // class, which is loaded separately so the order of CSS definitions is not
  // guaranteed. Therefore, increase specifity to ensure overrides apply.
  ::slotted([slot='icon']) {
    .button & {
      display: inline-flex;
      position: relative;
      writing-mode: horizontal-tb;
      fill: currentColor;
      color: var(--_icon-color);
      font-size: var(--_icon-size);
      inline-size: var(--_icon-size);
      block-size: var(--_icon-size);
    }

    .button:hover & {
      color: var(--_hover-icon-color);
    }

    .button:focus & {
      color: var(--_focus-icon-color);
    }

    .button:active & {
      color: var(--_pressed-icon-color);
    }

    .button:disabled & {
      color: var(--_disabled-icon-color);
      opacity: var(--_disabled-icon-opacity);
    }
  }
}