body{font-family:Arial,sans-serif;background-color:#f9f9f9;color:#333;margin:0;padding:0;display:flex;justify-content:center;align-items:center;min-height:100vh}.container{max-width:600px;width:100%;padding:20px;background-color:#fff;box-shadow:0 4px 8px rgba(0,0,0,.1);border-radius:8px;text-align:center}h1,h2,h3{color:#333}.message,h1,h2,h3{margin-bottom:20px}.message{color:#d9534f}.registration-form{display:flex;flex-direction:column;gap:10px}.input{border:1px solid #ccc;border-radius:4px}.button,.input{padding:10px;font-size:16px}.button{border:none;border-radius:4px;background-color:#5bc0de;color:#fff;cursor:pointer;transition:background-color .3s}.button:hover{background-color:#31b0d5}.attendees-list{list-style-type:none;padding:0;margin:0}.attendee-item{padding:10px;border-bottom:1px solid #ccc}.event-details{margin-top:20px;padding:10px;background-color:#f1f1f1;border-radius:4px;text-align:left}