a11y(darkmode): use a button for the theme toggle (#1335)

Andrew

2024-08-24 4c9e8601504f76dcc3c273ea8ad1862df432b7b4

 quartz/styles/callouts.scss

@@ -10,7 +10,7 @@
  transition: max-height 0.3s ease;
  box-sizing: border-box;

  & > *:nth-child(2) {
  & > .callout-content > :first-child {
    margin-top: 0;
  }