The Code

                    
                        // App Controller / Entry Point
                        function getValues() {
                            // get the users input
                            // decide what to do with it
                            let userInput = document.getElementById('message').value;
                            
                            let reversedInput = reverseString(userInput)
                        
                            displayString(reversedInput);
                        }
                        
                        // Business Logic
                        function reverseString(message) {
                            // take a string, return it in reverse
                            let reversedMessage = ''
                        
                            //  reverse the string
                            for (let index = message.length - 1; index >= 0; index = index - 1){
                                reversedMessage += message[index];
                            }
                        
                            return reversedMessage;
                        }
                        // View Function
                        function displayString(reversedMessage) {
                            // show the string on the page / assign text input to reversedMessage
                            document.getElementById('msg').textContent = reversedMessage;
                            // you want to remove the class d-none to get the alert to show / display
                            document.getElementById('alert').classList.remove('d-none')
                        }