/* 侧边栏：区分不可点击的章节标题与可点击的页面链接 */
.md-nav__item--nested > .md-nav__link {
  opacity: 0.7;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 700;
}

.md-nav__item--nested > .md-nav__link:hover {
  opacity: 0.7;
  cursor: default;
}