body,html{
	padding: 0;
	margin: 0;
}
#tree-module{
	max-width: 500px;
	width: 100%;
	margin: 30px auto;
}
.visible {
    margin: 5px 18px;
    background-color: #ffffff;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
}
.hidden {
    display: none;
}
.title{
    font-family: "Microsoft YaHei UI";
    font-size: 14px;
    color: #6898c2;
    line-height: 1.5em;
}
.title:hover{
    color: blue;
    cursor: pointer;
}
.red{
    color: red;
}
.add,.del{
    margin-left: 20px;
    cursor: pointer;
    font-size: 30px;
}