@mdit/plugin-spoiler/spoiler.css

spoiler plugin for MarkdownIt

.spoiler {
  background-color: currentColor;
  border-radius: 0.2em;
  transition: background ease 0.5s;
  cursor: help;
}

.spoiler:not(:hover) * {
  background-color: inherit;
  color: inherit;
}

.spoiler:hover,
.spoiler:focus {
  background-color: transparent;
}