.tarefa {
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #000000;
}

.tarefa:last-child {
    margin-bottom: 0;
}

.tarefa:nth-child(1) { background-color: #ffcccc; }
.tarefa:nth-child(2) { background-color: #ccffcc; }
.tarefa:nth-child(3) { background-color: #ccccff; }
.tarefa:nth-child(4) { background-color: #ffffcc; }
.tarefa:nth-child(5) { background-color: #ffccff; }