main.js

const search = document.querySelector('#search');
const todos = document.querySelectorAll('ul li');
const notFound = document.querySelector('#notFound');

search.addEventListener('keyup', filterFunctionality);

function filterFunctionality(e) {
  let searching = e.target.value.toLowerCase();

  // Filters the todo
  [...todos].forEach(todo => {
    let todoContent = todo.textContent;
    if (todoContent.toLowerCase().includes(searching)) {
      todo.style.display = 'block';
    } else {
      todo.style.display = 'none';
    }
  });

  // Displays No Todo Found
  let result = [...todos].every(todo => {
    return todo.style.display === 'none';
  });

  result === true
    ? (notFound.style.display = 'block')
    : (notFound.style.display = 'none');
}