/* Base */
:root {
  color-scheme: light dark;
  --background: #f4f2ea;
  --text: #20211f;
  --muted: #686a64;
  --link: #0047a5;
  --visited: #6b356f;
  --border: #8a8c84;
  --heading-rule: #b1b2aa;
  --code-background: #e8e6dd;
  --pre-background: #eceae2;
  --focus: #b23a24;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--background);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  font-size: 100%;
  letter-spacing: 0;
}

body {
  margin: 0;
  min-width: 0;
  line-height: 1.65;
  overflow-wrap: break-word;
}

.site-header,
main,
.site-footer {
  width: min(100% - 2rem, 760px);
  margin-inline: auto;
}

main {
  min-height: 55vh;
  padding-block: 2.5rem 4rem;
}

article {
  max-width: 68ch;
  line-height: 1.8;
}

/* Typography */
h1,
h2,
h3 {
  line-height: 1.3;
  letter-spacing: 0;
  overflow-wrap: anywhere;
}

h1 {
  margin: 0 0 1.5rem;
  font-size: 1.75rem;
}

h2 {
  margin: 2.75rem 0 1rem;
  padding-bottom: 0.3rem;
  border-bottom: 1px solid var(--heading-rule);
  font-size: 1.075rem;
  font-weight: 600;
}

h3 {
  margin: 2rem 0 0.75rem;
  font-size: 1rem;
}

p,
ul,
ol,
dl {
  margin-block: 0 1.25rem;
}

hr {
  margin-block: 2.5rem;
  border: 0;
  border-top: 1px solid var(--border);
}

/* Links */
a {
  color: var(--link);
  text-decoration: underline;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.16em;
}

a:visited {
  color: var(--visited);
}

a:hover {
  text-decoration-thickness: 0.14em;
}

a:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

/* Navigation */
.site-header {
  position: relative;
  padding-block: 1.5rem 1rem;
  border-bottom: 2px solid var(--border);
}

.site-identity,
.site-nav,
.site-footer,
.document-meta,
.document-view,
.document-list time,
.document-kind,
.series-position,
.navigation-label,
.chapter-number,
.list-updated {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

.site-identity {
  display: inline-block;
  margin-bottom: 1rem;
  color: var(--text);
  font-weight: 400;
}

.site-identity .site-root,
.site-identity .site-root:visited {
  color: var(--text);
  font-weight: 700;
  text-decoration: none;
}

.site-identity .site-root:hover,
.site-identity .site-root:focus-visible {
  text-decoration: underline;
}

.site-identity .site-crumb,
.site-identity .site-crumb:visited,
.site-identity .site-current,
.site-identity .site-current:visited {
  color: var(--text);
  text-decoration: none;
}

.site-identity .site-crumb:hover,
.site-identity .site-crumb:focus-visible,
.site-identity .site-current:hover,
.site-identity .site-current:focus-visible {
  color: var(--text);
  text-decoration: underline;
}

.site-identity .site-separator {
  color: var(--text);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.15rem;
  line-height: 1.5;
}

.site-nav a[aria-current="page"] {
  color: var(--text);
  font-weight: 700;
}

.skip-link {
  position: absolute;
  top: -6rem;
  left: 0;
  z-index: 1;
  padding: 0.5rem;
  background: var(--background);
}

.skip-link:focus {
  top: 0.25rem;
}

/* Documents */
.home-page {
  width: 100%;
  max-width: 760px;
  margin-inline: auto;
}

.home-page h1 {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  font-size: 1.625rem;
}

.home-intro {
  max-width: 68ch;
  font-size: 1rem;
  line-height: 1.7;
}

.home-page .site-nav {
  margin-top: 0;
  font-size: 1rem;
}

.home-pgp {
  font-size: 0.875rem;
}

.home-page .recent,
.home-page .announcements {
  margin-top: 2.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
}

.home-page .recent h2,
.home-page .announcements h2 {
  margin-top: 0;
  font-size: 1.125rem;
}

.document-header {
  margin-bottom: 2rem;
}

.document-meta {
  margin-bottom: 1.25rem;
  color: var(--muted);
  font-size: 0.875rem;
}

.document-meta div {
  display: grid;
  grid-template-columns: 9ch minmax(0, 1fr);
  gap: 1ch;
}

.document-meta dt,
.document-meta dd {
  margin: 0;
}

.document-view {
  margin-block: 1rem;
  color: var(--muted);
  font-size: 0.875rem;
}

.document-list {
  padding: 0;
  list-style: none;
}

.document-list li {
  min-width: 0;
  margin-bottom: 0.7rem;
}

.recent .document-list li,
.updates-list .document-list li {
  display: grid;
  grid-template-columns: max-content max-content minmax(0, 1fr);
  gap: 0.25rem 0.8rem;
  align-items: baseline;
}

.journal-list li,
.announcement-list li {
  display: grid;
  grid-template-columns: max-content minmax(0, 1fr);
  gap: 0.25rem 1rem;
  align-items: baseline;
}

.document-list time,
.document-kind,
.chapter-number,
.list-updated {
  color: var(--muted);
  font-size: 0.875rem;
}

.series-chapter-list .chapter-number {
  display: inline-block;
  width: 3ch;
}

.list-updated {
  margin-left: 0.6rem;
  white-space: nowrap;
}

.series-position {
  margin-top: -0.75rem;
  color: var(--muted);
  font-size: 0.875rem;
}

.document-navigation {
  margin-top: 3rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
}

.document-navigation ul {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0;
  list-style: none;
}

.document-navigation li {
  display: flex;
  max-width: 46%;
  flex-direction: column;
}

.journal-navigation ul {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
}

.journal-navigation li {
  max-width: none;
  line-height: 1.35;
}

.journal-navigation .previous-link {
  grid-column: 1;
  align-items: flex-start;
}

.journal-navigation .next-link {
  grid-column: 2;
  align-items: flex-end;
  text-align: right;
}

.series-navigation ul {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: start;
  gap: 1rem;
}

.series-navigation li {
  min-width: 0;
  max-width: none;
  line-height: 1.35;
}

.series-navigation .series-previous {
  grid-column: 1;
  align-items: flex-start;
}

.series-navigation .series-index-link {
  grid-column: 2;
  align-items: center;
  text-align: center;
}

.series-navigation .series-next {
  grid-column: 3;
  align-items: flex-end;
  text-align: right;
}

.navigation-label {
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.2;
}

.table-of-contents {
  margin-block: 2.5rem;
  padding-left: 1rem;
  border-left: 3px solid var(--border);
}

.table-of-contents h2 {
  margin-top: 0;
}

.table-of-contents nav > ul {
  padding-left: 1.2rem;
}

.table-of-contents ul {
  margin-bottom: 0;
}

/* Code */
code,
kbd,
samp,
pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

:not(pre) > code {
  padding-inline: 0.18em;
  background: var(--code-background);
}

pre {
  max-width: 100%;
  margin-block: 1.5rem;
  padding: 0.75rem 1rem;
  overflow-x: auto;
  background: var(--pre-background);
  font-size: 0.9rem;
  line-height: 1.55;
  overflow-wrap: normal;
  white-space: pre;
}

pre code {
  padding: 0;
  background: transparent;
}

/* Tables and quotations */
table {
  display: block;
  max-width: 100%;
  margin-block: 1.5rem;
  overflow-x: auto;
  border-collapse: collapse;
}

th,
td {
  padding: 0.45rem 0.75rem;
  border: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

blockquote {
  margin: 1.5rem 0;
  padding-left: 1rem;
  border-left: 3px solid var(--border);
  color: var(--muted);
}

blockquote > :last-child {
  margin-bottom: 0;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
  margin-block: 1.5rem 0.5rem;
}

/* Footer */
.site-footer {
  padding-block: 1.5rem 2.5rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.65;
}

.site-footer nav,
.site-footer p {
  margin-bottom: 0.8rem;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
  :root {
    --background: #181916;
    --text: #e6e7e2;
    --muted: #a8aaa3;
    --link: #7eb4ef;
    --visited: #c5a0cb;
    --border: #777a72;
    --heading-rule: #555850;
    --code-background: #292a26;
    --pre-background: #23241f;
    --focus: #ff9b76;
  }
}

/* Mobile */
@media (max-width: 520px) {
  .site-header,
  main,
  .site-footer {
    width: min(100% - 1.25rem, 760px);
  }

  main {
    padding-block: 2rem 3rem;
  }

  h1 {
    font-size: 1.5rem;
  }

  .recent .document-list li,
  .updates-list .document-list li,
  .journal-list li,
  .announcement-list li {
    display: block;
  }

  .document-kind,
  .document-list time {
    margin-right: 0.45rem;
  }

  .document-navigation li {
    width: 100%;
    max-width: none;
  }

  .list-updated {
    display: block;
    margin-left: 3ch;
    white-space: normal;
  }
}