fix indexing causing main thread freeze, various polish

Jacky Zhao

2023-07-04 ab9da02c60c962128820e6874e6f07c98bc3dda7

 quartz/components/styles/toc.scss

@@ -38,7 +38,7 @@
    & > li > a {
      color: var(--dark);
      opacity: 0.35;
      transition: 0.5s ease opacity;
      transition: 0.5s ease opacity, 0.3s ease color;
      &.in-view {
        opacity: 0.75;
      }