HTML: <div class="wrapper"> <h1>All Unique Characters</h1><br> <p>A prompt from <a href="https://buttondown.email/cassidoo/archive/keep-your-face-always-toward-the-sunshine-and/">Cassidy Williams' newsletter</a>: <br>Write a function that determines if all <br>the characters in a given string are unique.</p><br> <form class="form-start"> <input type="text" class="text" id="unique-text" placeholder="Insert your..