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<!DOCTYPE html> <html> <head> <style> .example { border: 1px solid black; padding 8px; } </style> </head> <body> <h1>The Document Object</h1> <h2>The getElementsByClassName() Method</h2> <p>Change the background color of all elements with class="example":</p> <div class="example"> A div with class="example" </div> <br> <div class="example"> A div with class="example" </div> <p class="example"> A p element with class="example". </p> <p>A <span class="example">span</span> element with class="example".</p> <script> const collection = document.getElementsByClassName("example"); for (let i = 0; i < collection.length; i++) { collection[i].style.backgroundColor = "red"; } </script> </body> </html>
