Is class attribute work with span tag
https://code.sololearn.com/W9lmu0hxi1gs/?ref=app HTML file: <!DOCTYPE html> <html> <head> <title>Registration form</title> </head> <body bgcolor="burlywood"> <h1 align="center">Registration form</h1> <form action="https:// www.facebook.com" target="_blank"> first name: <br /> <input type="name" placeholder="enter your name" /> <br /> last name: <br /> <input type="name" placeholder="enter your last name"/> <br /> <br /> gender selection: <br /> <input type="radio" name="gender" />Male <br /> <input type="radio" name="gender" />Female <br /> <br /> email: <br /> <input type="email" placeholder="enter your email address"/> <br /> password: <br /> <input type="password" placeholder="enter your password" /> <br /> <br /> you favourite animals:<br /> dog<input type="checkbox" value="dog" /> <br /> cow<input type="checkbox" value="cow" /> <br /> cat<input type="checkbox" value="cat" /> <br /> <br />message: <br /> <textarea placeholder="enter your message" text></textarea> <br /> <br /> <span class="center"><input type="submit" value="SUBMIT" align="center"/></span> </form> </body> </html> CSS file: .center{ text-align:center; } But submit button didn't show in the center. Please answer me.