var input = document.querySelector('input[nome="nome_mysql"]');

console.log(div, input)

​

function toggleElements(show, hide) {

    show.style.display = 'block';

    hide.style.display = 'none';

    show.focus();

}

​

div.addEventListener('click', function() {

    input.value = this.innerText;

    toggleElements(input, this);

});

input.addEventListener('blur', function() {

    div.innerText = this.value;

    toggleElements(div, this);

});

​