A1x1On2015,
<!DOCTYPE HTML>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<style type="text/css">
.container {
background-color: #FF0000;
padding: 20px;
}
.btnInsert {
background: #FFCC00;
cursor: pointer;
}
.blockInsertTask{
display: none;
background-color: #00FF00;
height: 200px;
}
</style>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script>
$(function() {
$(".container").click(function(event) {
if (!$(event.target).is(".blockInsertTask")) $(".blockInsertTask")[$(event.target).is(".btnInsert") ? "fadeIn" : "fadeOut"]()
})
});
</script>
</head>
<body>
<div class="container">
<button class="btnInsert">Добавить задачу</button>
<div class="blockInsertTask"> блок </div>
</div>
</body>
</html>