:root {
  --paper: #f4f2ec;
  --page: #fffefa;
  --ink: #29342f;
  --muted: #6c756f;
  --line: #d9d3c8;
  --green: #3f7654;
  --green-soft: #e7efe8;
  --blue: #477b9d;
  --blue-soft: #e8f0f5;
  --gold: #ad772d;
  --gold-soft: #f6ecd9;
  --wine: #925463;
  --shadow: 0 12px 34px rgba(49, 43, 32, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a {
  color: var(--blue);
  text-decoration: none;
}

a:focus-visible {
  outline: 3px solid rgba(71, 123, 157, 0.35);
  outline-offset: 2px;
}

.reader-topbar {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  padding: 10px max(20px, calc((100vw - 1440px) / 2));
  border-bottom: 1px solid var(--line);
  background: rgba(255, 254, 250, 0.96);
  backdrop-filter: blur(12px);
}

.reader-brand {
  display: grid;
  color: var(--ink);
}

.reader-brand strong {
  font-size: 0.95rem;
}

.reader-brand span {
  color: var(--muted);
  font-size: 0.68rem;
}

.reader-actions {
  display: flex;
  gap: 7px;
}

.reader-actions a {
  display: grid;
  min-height: 38px;
  padding: 7px 11px;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 7px;
  font-size: 0.72rem;
  font-weight: 800;
}

.reader-actions .primary {
  border-color: var(--green);
  background: var(--green);
  color: white;
}

.reader-layout {
  display: grid;
  grid-template-columns: 190px minmax(0, 820px) 190px;
  justify-content: center;
  gap: 22px;
  width: min(1440px, calc(100% - 28px));
  margin: 22px auto 60px;
  align-items: start;
}

.document-shelf,
.page-toc {
  position: sticky;
  top: 86px;
}

.document-shelf {
  display: grid;
  gap: 16px;
  padding: 13px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--page);
  box-shadow: var(--shadow);
}

.document-shelf section {
  display: grid;
  gap: 3px;
}

.document-shelf h2 {
  margin: 0 0 4px;
  color: var(--muted);
  font-size: 0.66rem;
  text-transform: uppercase;
}

.document-shelf a {
  min-height: 31px;
  padding: 7px 8px;
  border-radius: 5px;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
}

.document-shelf a.active {
  background: var(--green-soft);
  color: var(--green);
}

.document-main {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--page);
  box-shadow: var(--shadow);
}

.document-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 26px;
  border-bottom: 1px solid var(--line);
  background: #faf8f2;
  color: var(--muted);
  font-size: 0.68rem;
}

.document-meta span {
  color: var(--green);
  font-weight: 900;
  text-transform: uppercase;
}

.document-meta code {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.markdown-body {
  padding: 30px clamp(22px, 5vw, 58px) 54px;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3 {
  scroll-margin-top: 86px;
  letter-spacing: 0;
}

.markdown-body h1 {
  margin: 0 0 26px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
  font-size: clamp(1.75rem, 4vw, 2.45rem);
  line-height: 1.12;
}

.markdown-body h2 {
  margin: 38px 0 13px;
  padding-left: 11px;
  border-left: 4px solid var(--green);
  font-size: 1.25rem;
}

.markdown-body h3 {
  margin: 25px 0 9px;
  color: #385d48;
  font-size: 0.98rem;
}

.markdown-body p,
.markdown-body li {
  font-size: 0.88rem;
  line-height: 1.75;
}

.markdown-body p {
  margin: 0 0 14px;
}

.markdown-body ul,
.markdown-body ol {
  display: grid;
  gap: 5px;
  margin: 8px 0 18px;
  padding-left: 24px;
}

.markdown-body li::marker {
  color: var(--green);
  font-weight: 900;
}

.markdown-body strong {
  color: #1f442e;
}

.markdown-body code {
  padding: 2px 5px;
  border-radius: 4px;
  background: #efede7;
  color: var(--wine);
  font-size: 0.82em;
}

.markdown-body blockquote {
  margin: 20px 0;
  padding: 16px 18px;
  border-left: 5px solid var(--gold);
  background: var(--gold-soft);
  color: #5d4c35;
}

.markdown-body blockquote p {
  margin: 0;
  font-size: 0.94rem;
}

.code-block {
  margin: 16px 0 22px;
  padding: 17px;
  overflow: auto;
  border: 1px solid #31423a;
  border-radius: 8px;
  background: #202b26;
  color: #e9efe9;
  font-size: 0.78rem;
  line-height: 1.65;
}

.code-block code {
  padding: 0;
  background: transparent;
  color: inherit;
}

.table-scroll {
  margin: 16px 0 24px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.78rem;
}

th,
td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
  line-height: 1.5;
}

th {
  background: var(--blue-soft);
  color: #355f79;
  font-size: 0.7rem;
  text-transform: uppercase;
}

tr:last-child td {
  border-bottom: 0;
}

.flow-diagram {
  margin: 18px 0 24px;
  padding: 14px;
  border: 1px solid rgba(71, 123, 157, 0.32);
  border-radius: 8px;
  background: var(--blue-soft);
}

.flow-diagram figcaption {
  margin-bottom: 9px;
  color: var(--blue);
  font-size: 0.66rem;
  font-weight: 900;
  text-transform: uppercase;
}

.flow-edges {
  display: grid;
  gap: 6px;
}

.flow-edge {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr);
  align-items: stretch;
  gap: 6px;
}

.flow-node {
  display: grid;
  min-height: 46px;
  padding: 8px 10px;
  place-items: center;
  border: 1px solid rgba(71, 123, 157, 0.28);
  border-radius: 6px;
  background: white;
  color: #304a3d;
  text-align: center;
  font-size: 0.73rem;
  font-weight: 800;
}

.flow-node small {
  display: block;
  color: var(--muted);
  font-size: 0.66rem;
  font-weight: 600;
}

.flow-arrow {
  display: grid;
  place-items: center;
  color: var(--blue);
  font-weight: 900;
}

.task-item {
  display: grid;
  grid-template-columns: 18px minmax(0, 1fr);
  gap: 8px;
  align-items: start;
  list-style: none;
}

.doc-checkbox {
  width: 16px;
  height: 16px;
  margin-top: 5px;
  border: 1px solid #9ca69f;
  border-radius: 4px;
  background: white;
}

.doc-checkbox.checked {
  border-color: var(--green);
  background: var(--green);
  box-shadow: inset 0 0 0 3px white;
}

.page-toc {
  display: grid;
  gap: 3px;
  max-height: calc(100vh - 108px);
  overflow: auto;
  padding: 3px 0;
}

.page-toc strong {
  margin-bottom: 6px;
  color: var(--muted);
  font-size: 0.68rem;
  text-transform: uppercase;
}

.page-toc a,
.page-toc span {
  padding: 5px 7px;
  border-left: 2px solid var(--line);
  color: var(--muted);
  font-size: 0.7rem;
  line-height: 1.35;
}

.page-toc a:hover {
  border-left-color: var(--green);
  color: var(--green);
}

.page-toc .level-3 {
  padding-left: 16px;
  font-size: 0.66rem;
}

@media (max-width: 1080px) {
  .reader-layout {
    grid-template-columns: 180px minmax(0, 820px);
  }

  .page-toc {
    display: none;
  }
}

@media (max-width: 760px) {
  .reader-topbar {
    position: static;
  }

  .reader-layout {
    grid-template-columns: 1fr;
    margin-top: 10px;
  }

  .document-shelf {
    position: static;
    display: flex;
    gap: 12px;
    overflow-x: auto;
  }

  .document-shelf section {
    flex: 0 0 150px;
  }

  .document-meta {
    padding: 11px 16px;
  }
}

@media (max-width: 520px) {
  .reader-topbar {
    align-items: stretch;
    flex-direction: column;
  }

  .reader-actions {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .markdown-body {
    padding: 23px 17px 40px;
  }

  .document-meta code {
    display: none;
  }

  .flow-edge {
    grid-template-columns: 1fr;
  }

  .flow-arrow {
    min-height: 20px;
    transform: rotate(90deg);
  }
}