<head>
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
  
</head>
<body>
  <button>toggleClass</button>
  <p class="red">
  テックアカデミーでtoggleClassを学習してみよう。
  </p>
</body>
.red {color : red}
$("button").click(function(){
  $("p").toggleClass("red");
});

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External JavaScript

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