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<!DOCTYPE html> <html> <body> <h1>The HTMLCollection Object</h1> <h2>The length Property</h2> <p>Click "Change" to change all elements with class="myclass":</p> <button onclick="myFunction()">Change</button> <p>I am a paragraph.</p> <p class="myclass">I am a paragraph.</p> <p class="myclass">I am a paragraph.</p> <script> function myFunction() { const collection = document.getElementsByClassName("myclass"); for (let i = 0; i < collection.length; i++) { collection[i].style.fontSize = "24px"; } } </script> </body> </html>
