анимация расширения блока на React

import React from "react";
import ReactDOM from "react-dom";
import "./styles.css";

class App extends React.Component {
  constructor() {
    super();
    this.state = {
      value: "",
      text: "",
      isVisible: false
    };
    this.handleChange = this.handleChange.bind(this);
    this.toggleVisibility = this.toggleVisibility.bind(this);
  }

  toggleVisibility() {
    this.setState(prevState => {
      return {
        isVisible: !prevState.isVisible
      };
    });
  }
  handleChange(e) {
    const { value } = e.target;
    this.setState(() => {
      return {
        value
      };
    });
  }

  render() {
    const { isVisible } = this.state;
    const text = isVisible ? "Hide text" : "Show text";
    const btnText = isVisible ? "Hide" : "