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<!DOCTYPE html> <html> <head> <style> .mystyle { width: 300px; height: 50px; text-align: center; background-color: coral; color: white; margin-bottom: 10px; } </style> </head> <body> <p>In this example, we first search for the element in the document with id="myDIV". Then, if this element has a class of "mystyle" - change its font size.</p> <div id="myDIV" class="mystyle"> I am a DIV element </div> <button onclick="myFunction()">Try it</button> <script> function myFunction() { var x = document.getElementById("myDIV"); if (x.className === "mystyle") { x.style.fontSize = "30px"; } } </script> </body> <!-- Mirrored from www.w3schools.com/jsref/tryit.asp?filename=tryjsref_element_classname6 by HTTrack Website Copier/3.x [XR&CO'2014], Fri, 23 Jan 2015 08:28:29 GMT --> </html>
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