mostra e esconde

Copie e cole o código abaixo.

<div class="pre-spoiler"><br /> <input id="xs" value="Mostrar" style="margin-left: 50px; padding: 0px; width: 80px; " onclick="if (this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display != '') { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = '';this.innerText = ''; this.value = 'Ocultar'; } else { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = 'none'; this.value = 'mostrar';}" type="button"> </div><br /> <div><br /> <div class="spoiler" style="display: none;"><br /> Copie e cole o código abaixo.<br /> <br /> </div><br /> </div>