:root {
  color-scheme: light;
  font-family: "Noto Serif CJK TC", "Noto Serif TC", "Source Han Serif TC",
    "Microsoft JhengHei", serif;
  line-height: 1.9;
  color: #292524;
  background: #f8f7f4;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
}

a {
  color: #1d4ed8;
}

.skip-link {
  position: absolute;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 100;
  padding: 0.35rem 0.7rem;
  color: #fff;
  background: #1e3a8a;
  border-radius: 0.35rem;
  transform: translateY(-150%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-shell {
  display: grid;
  grid-template-columns:
    minmax(12rem, 16rem)
    minmax(0, 44rem)
    minmax(13rem, 17rem);
  justify-content: center;
  gap: 1.5rem;
  max-width: 96rem;
  min-height: 100vh;
  margin: 0 auto;
  padding: 1rem 1.5rem 4rem;
}

.article {
  min-width: 0;
  width: 100%;
  padding: 0 0.5rem;
}

.article:focus {
  outline: 2px solid #93c5fd;
  outline-offset: 0.5rem;
}

.article h1,
.article h2,
.article h3,
.article h4 {
  line-height: 1.35;
  scroll-margin-top: 1rem;
}

.article h1 {
  margin-top: 0;
  font-size: clamp(1.9rem, 4vw, 2.7rem);
}

.article h2 {
  margin-top: 3rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid #d6d3d1;
}

.article h3 {
  margin-top: 2rem;
}

.article blockquote {
  margin-left: 0;
  padding-left: 1rem;
  border-left: 0.25rem solid #a8a29e;
  color: #57534e;
}

.article pre {
  overflow-x: auto;
  padding: 1rem;
  background: #e7e5e4;
  border-radius: 0.4rem;
}

.article code {
  font-family: "Cascadia Code", Consolas, monospace;
}

.ruby-container {
  display: inline-flex;
  flex-direction: column;
  text-align: center;
  vertical-align: bottom;
}

.anno-c {
  margin-right: -2em;
  font-size: 0.7em;
  line-height: 1;
  letter-spacing: 2em;
  opacity: 0.8;
}

.anno-w {
  font-size: 0.7em;
  line-height: 1;
  opacity: 0.8;
}

.emphasis-dot {
  padding-bottom: 0.25em;
  background-image: radial-gradient(
    circle at center,
    currentColor 1.5px,
    transparent 1.5px
  );
  background-position: 0 bottom;
  background-repeat: repeat-x;
  background-size: 1em 0.3em;
}

.spoiler {
  padding: 0 0.15em;
  color: transparent;
  background: #292524;
  border-radius: 0.2em;
  cursor: pointer;
}

.spoiler:hover,
.spoiler:focus,
.spoiler:focus-visible {
  color: inherit;
  background: transparent;
  outline: none;
}

.abbr-term {
  cursor: help;
  text-decoration: underline dotted;
  text-underline-offset: 0.2em;
}

.reading-sidebar {
  position: sticky;
  top: 1rem;
  align-self: start;
  max-height: calc(100vh - 2rem);
  overflow: auto;
  padding: 0.8rem 1rem 1rem;
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid #d6d3d1;
  border-radius: 0.65rem;
  box-shadow: 0 0.5rem 1.5rem rgba(28, 25, 23, 0.08);
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.sidebar-toggle {
  flex: none;
  padding: 0.4rem 0.7rem;
  color: #292524;
  background: #fff;
  border: 1px solid #a8a29e;
  border-radius: 0.35rem;
  cursor: pointer;
}

.sidebar-toggle:hover,
.sidebar-toggle:focus-visible {
  background: #f5f5f4;
}

.sidebar-content {
  margin-top: 0.75rem;
}

.toc-list {
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.92rem;
}

.toc-list li {
  margin: 0.35rem 0;
}

.toc-list li[data-level="3"] {
  margin-left: 0.8rem;
}

.toc-list li[data-level="4"] {
  margin-left: 1.6rem;
}

.toc-list a {
  text-decoration: none;
}

.toc-list a:hover,
.toc-list a:focus-visible {
  text-decoration: underline;
}

.glossary-list {
  margin: 0;
  font-size: 0.92rem;
}

.glossary-list dt {
  margin-top: 0.7rem;
  font-weight: 700;
}

.glossary-list dd {
  margin: 0;
  color: #57534e;
}

.sidebar-empty {
  margin: 0;
  color: #78716c;
  font-size: 0.9rem;
}

.reading-sidebar.is-collapsed .sidebar-header {
  justify-content: flex-end;
}

.reading-sidebar.is-collapsed .sidebar-header > strong {
  display: none;
}

@media (max-width: 800px) {
  .site-shell {
    display: block;
    padding: 1rem 1rem 3rem;
  }

  .article {
    padding: 0;
  }

  .reading-sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    z-index: 20;
    width: min(88vw, 22rem);
    height: 100vh;
    max-height: none;
    border-radius: 0;
    transition: transform 180ms ease;
  }

  .reading-sidebar--left {
    left: 0;
  }

  .reading-sidebar--right {
    right: 0;
  }

  .reading-sidebar.is-collapsed {
    width: auto;
    height: auto;
    min-width: 0;
    padding: 0.5rem;
    border-radius: 0 0 0.65rem 0;
    overflow: visible;
  }

  .reading-sidebar--left.is-collapsed {
    border-radius: 0 0 0.65rem 0;
  }

  .reading-sidebar--right.is-collapsed {
    border-radius: 0 0 0 0.65rem;
  }

  .reading-sidebar.is-collapsed .sidebar-toggle {
    padding: 0.35rem 0.55rem;
  }
}