New source found from dndbeyond.com

ddb_main/tools/js/CharacterSheet/components/SpeedBox/SpeedBox.tsx

@@ -1,4 +1,3 @@
-import { visuallyHidden } from "@mui/utils";
 import React from "react";
 
 import {
@@ -14,6 +13,7 @@ import {
 } from "@dndbeyond/character-rules-engine/es";
 
 import { NumberDisplay } from "~/components/NumberDisplay";
+import a11yStyles from "~/styles/accessibility.module.css";
 
 interface Props {
   speeds: SpeedInfo;
@@ -47,7 +47,7 @@ export default class SpeedBox extends React.PureComponent<Props> {
 
     return (
       <section className="ct-speed-box" onClick={this.handleSpeedsClick}>
-        <h2 style={visuallyHidden}>Speed</h2>
+        <h2 className={a11yStyles.screenreaderOnly}>Speed</h2>
         <BoxBackground StyleComponent={BeveledBoxSvg94x89} theme={theme} />
         <div
           className={`ct-speed-box__heading ${