.book .book-summary .chapter>.articles {
	overflow: hidden;
	max-height: 0px;
}

.book .book-summary .chapter.expanded>.articles {
	max-height: 9999px;
}

.book .book-summary .exc-trigger {
	position: absolute;
	left: 12px;
	top: 12px;
}

.book .book-summary ul.summary li a,
.book .book-summary ul.summary li span {
	padding-left: 30px;
}

.book .book-summary .exc-trigger:before {
	content: "\f105";
}

.book .book-summary .expanded>a .exc-trigger:before,
.book .book-summary .expanded>span .exc-trigger:before {
	content: "\f107";
}

.chapter a:hover,
.chapter span:hover {
	cursor: pointer;
	/* 可以添加其他悬停样式 */
}