.guide-page {
  background:
    linear-gradient(var(--border-subtle) 1px, transparent 1px) 0 0 / 100% 80px,
    var(--bg-base);
}

.guide-header .site-nav .is-current {
  color: var(--fg-primary);
  background: var(--bg-raised);
  box-shadow: inset 0 -2px 0 var(--brand);
}

.guide-shell {
  width: 100%;
  min-height: calc(100dvh - 80px);
  display: block;
  border-bottom: 1px solid var(--border-default);
}

.guide-rail {
  min-width: 0;
  padding: clamp(2.8rem, 4vw, 4.5rem) var(--page-pad);
  border-bottom: 1px solid var(--border-default);
  background: color-mix(in srgb, var(--bg-base) 92%, var(--bg-raised));
}

.guide-rail-inner {
  display: grid;
  grid-template-columns: minmax(280px, 0.62fr) minmax(620px, 1.38fr);
  gap: clamp(3rem, 7vw, 8rem);
  align-items: end;
}

.guide-intro {
  max-width: 560px;
}

.guide-page-title {
  max-width: 520px;
  margin: 1.7rem 0 1.2rem;
  font-size: clamp(2.65rem, 3.2vw, 3.85rem);
  font-weight: 600;
  letter-spacing: -0.058em;
  line-height: 0.98;
}

.guide-page-lead {
  max-width: 470px;
  margin: 0;
  color: var(--fg-secondary);
  font-family: var(--font-copy);
  font-size: 1.08rem;
  line-height: 1.65;
}

.guide-doc-nav {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid var(--border-emphasis);
}

.doc-tab {
  position: relative;
  width: 100%;
  min-height: 132px;
  padding: 1.15rem 2.6rem 1.15rem 1rem;
  display: grid;
  justify-items: start;
  border: 0;
  border-right: 1px solid var(--border-default);
  border-bottom: 1px solid var(--border-default);
  color: var(--fg-secondary);
  background: transparent;
  text-align: left;
  cursor: pointer;
  transition: color 180ms var(--ease-out), background 180ms var(--ease-out);
}

.doc-tab:last-child {
  border-right: 0;
}

.doc-tab::after {
  position: absolute;
  top: 50%;
  right: 1rem;
  color: var(--fg-muted);
  content: "→";
  font-family: var(--font-data);
  transform: translateY(-50%);
  transition: color 180ms ease-out, transform 220ms var(--ease-out);
}

.doc-tab:hover {
  color: var(--fg-primary);
  background: var(--bg-raised);
}

.doc-tab:hover::after,
.doc-tab.is-active::after {
  color: var(--brand-strong);
  transform: translate(3px, -50%);
}

.doc-tab.is-active {
  color: var(--fg-primary);
  background: var(--bg-overlay);
  box-shadow: inset 3px 0 0 var(--brand);
}

.doc-tab-index {
  margin-bottom: 0.42rem;
  color: var(--brand);
  font-family: var(--font-data);
  font-size: 0.62rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.doc-tab strong {
  font-size: 1rem;
  font-weight: 600;
}

.doc-tab small {
  margin-top: 0.2rem;
  color: var(--fg-muted);
  font-size: 0.74rem;
  line-height: 1.35;
}

.guide-reader {
  min-width: 0;
  background: color-mix(in srgb, var(--bg-base) 97%, var(--bg-raised));
}

.reader-toolbar {
  position: sticky;
  top: 0;
  z-index: 4;
  min-height: 70px;
  padding: 0 var(--page-pad);
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(260px, 380px) auto;
  align-items: center;
  gap: 1.5rem;
  border-bottom: 1px solid var(--border-default);
  background: color-mix(in srgb, var(--bg-base) 94%, transparent);
  backdrop-filter: blur(14px);
}

.reader-path {
  min-width: 0;
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
}

.reader-path span {
  color: var(--brand);
  font-family: var(--font-data);
  font-size: 0.64rem;
}

.reader-path strong {
  overflow: hidden;
  font-size: 0.82rem;
  font-weight: 500;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.reader-filter {
  min-height: 44px;
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  align-items: center;
  border: 1px solid var(--border-default);
  background: var(--bg-raised);
}

.reader-filter > svg {
  justify-self: center;
  fill: none;
  stroke: var(--fg-muted);
  stroke-width: 1.4;
}

.reader-filter:focus-within > svg {
  stroke: var(--brand-strong);
}

.reader-filter input {
  width: 100%;
  min-width: 0;
  height: 44px;
  padding: 0 0.85rem 0 0;
  border: 0;
  outline: 0;
  color: var(--fg-primary);
  background: var(--bg-raised);
  font-family: var(--font-sans);
  font-size: 0.76rem;
}

.reader-filter:focus-within {
  border-color: var(--brand);
  box-shadow: 0 1px 0 var(--brand);
}

.reader-filter input::placeholder {
  color: var(--fg-muted);
}

.reader-source {
  min-width: 44px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  color: var(--fg-secondary);
  font-size: 0.72rem;
  font-weight: 500;
  text-decoration: none;
}

.reader-source:hover {
  color: var(--brand-strong);
}

.reader-source svg {
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
}

.reader-body {
  display: grid;
  grid-template-columns: minmax(230px, 280px) minmax(0, 1fr);
  align-items: start;
}

.chapter-rail {
  position: sticky;
  top: 70px;
  max-height: calc(100dvh - 70px);
  padding: 2rem 1.35rem 3rem var(--page-pad);
  overflow-y: auto;
  border-right: 1px solid var(--border-default);
  scrollbar-width: thin;
  scrollbar-color: var(--border-emphasis) transparent;
}

.chapter-rail > p:first-child {
  margin: 0 0 1rem;
  color: var(--fg-muted);
  font-family: var(--font-data);
  font-size: 0.62rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.chapter-rail > p:first-child span {
  color: var(--brand);
}

.chapter-list {
  display: grid;
}

.chapter-list a {
  position: relative;
  min-height: 44px;
  padding: 0.68rem 0 0.68rem 1rem;
  display: block;
  border-left: 1px solid var(--border-subtle);
  color: var(--fg-muted);
  font-size: 0.72rem;
  line-height: 1.35;
  text-decoration: none;
  transition: color 150ms ease-out, border-color 150ms ease-out, background 150ms ease-out;
}

.chapter-list a::before {
  position: absolute;
  top: 50%;
  left: -2px;
  width: 3px;
  height: 0;
  content: "";
  background: var(--brand);
  transform: translateY(-50%);
  transition: height 180ms var(--ease-out);
}

.chapter-list a:hover,
.chapter-list a.is-current {
  color: var(--fg-primary);
  border-color: var(--border-emphasis);
  background: color-mix(in srgb, var(--bg-raised) 72%, transparent);
}

.chapter-list a:hover::before,
.chapter-list a.is-current::before {
  height: 16px;
}

.chapter-list a[data-depth="3"] {
  padding-left: 1.8rem;
  font-size: 0.67rem;
}

.chapter-list a[hidden] {
  display: none;
}

.chapter-empty {
  color: var(--fg-muted);
  font-family: var(--font-data);
  font-size: 0.65rem;
}

.markdown-body {
  width: min(100%, 1120px);
  min-width: 0;
  margin-inline: auto;
  padding: clamp(3.5rem, 6vw, 7rem) clamp(1.4rem, 5vw, 5.5rem) 8rem;
  color: var(--fg-secondary);
  transition: opacity 180ms ease-out;
}

.markdown-body[aria-busy="true"] {
  min-height: 70dvh;
}

.guide-loading {
  min-height: 52dvh;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 1rem;
  color: var(--fg-muted);
  font-family: var(--font-data);
  font-size: 0.68rem;
}

.guide-loading span {
  width: 34px;
  height: 2px;
  overflow: hidden;
  background: var(--border-default);
}

.guide-loading span::after {
  width: 50%;
  height: 100%;
  display: block;
  content: "";
  background: var(--brand);
  animation: guide-load 900ms var(--ease-out) infinite alternate;
}

@keyframes guide-load {
  from { transform: translateX(-100%); }
  to { transform: translateX(200%); }
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4 {
  color: var(--fg-primary);
  font-family: var(--font-sans);
  scroll-margin-top: 90px;
  text-wrap: balance;
}

.markdown-body h1 {
  max-width: 1000px;
  margin: 0 0 2rem;
  font-size: clamp(2.75rem, 4.3vw, 4.7rem);
  font-weight: 600;
  letter-spacing: -0.06em;
  line-height: 0.98;
}

.markdown-body h2 {
  margin: 5.5rem 0 1.4rem;
  padding-top: 1.2rem;
  border-top: 1px solid var(--border-emphasis);
  font-size: clamp(2rem, 3.2vw, 3.35rem);
  font-weight: 600;
  letter-spacing: -0.05em;
  line-height: 1.05;
}

.markdown-body h3 {
  margin: 3.3rem 0 1rem;
  color: var(--brand-strong);
  font-size: clamp(1.3rem, 2vw, 1.85rem);
  font-weight: 500;
  letter-spacing: -0.025em;
  line-height: 1.15;
}

.markdown-body h4 {
  margin: 2.5rem 0 0.85rem;
  font-size: 1.05rem;
  font-weight: 600;
}

.markdown-body p,
.markdown-body li {
  font-family: var(--font-copy);
  font-size: clamp(1rem, 1.25vw, 1.1rem);
  line-height: 1.78;
}

.markdown-body p {
  margin: 0 0 1.35rem;
}

.markdown-body ul,
.markdown-body ol {
  margin: 1.2rem 0 1.8rem;
  padding-left: 1.45rem;
}

.markdown-body li {
  margin: 0.45rem 0;
  padding-left: 0.25rem;
}

.markdown-body li::marker {
  color: var(--brand);
  font-family: var(--font-data);
}

.markdown-body a {
  color: var(--brand-strong);
  text-decoration-color: color-mix(in srgb, var(--brand) 45%, transparent);
  text-underline-offset: 0.18em;
}

.markdown-body a:hover {
  text-decoration-color: var(--brand-strong);
}

.markdown-body strong {
  color: var(--fg-primary);
  font-weight: 600;
}

.markdown-body blockquote {
  margin: 2rem 0;
  padding: 1rem 1.25rem;
  border-left: 3px solid var(--brand);
  color: var(--fg-secondary);
  background: var(--bg-raised);
}

.markdown-body blockquote p:last-child {
  margin-bottom: 0;
}

.markdown-body hr {
  height: 1px;
  margin: 4.5rem 0;
  border: 0;
  background: var(--border-default);
}

.markdown-body code {
  padding: 0.12em 0.32em;
  color: #c6e8e7;
  border: 1px solid var(--border-subtle);
  background: var(--bg-raised);
  font-family: var(--font-data);
  font-size: 0.82em;
  overflow-wrap: anywhere;
}

.markdown-body pre {
  position: relative;
  margin: 1.8rem 0 2.2rem;
  padding: 1.3rem 1.2rem;
  overflow: auto;
  border: 1px solid var(--border-default);
  background: #070b0e;
  scrollbar-width: thin;
  scrollbar-color: var(--border-emphasis) var(--bg-base);
}

.markdown-body pre code {
  padding: 0;
  border: 0;
  background: transparent;
  font-size: 0.78rem;
  line-height: 1.65;
  overflow-wrap: normal;
}

.markdown-body pre.formula-block {
  padding: 1.65rem;
  color: var(--fg-primary);
  border-left: 3px solid var(--brand);
  background: color-mix(in srgb, var(--bg-raised) 72%, var(--bg-base));
  white-space: normal;
}

.markdown-body pre.formula-block code {
  color: var(--fg-primary);
  font-size: 0.9rem;
  white-space: pre-wrap;
}

.formula-block .katex-display {
  margin: 0;
  padding: 0.35rem 0;
  overflow-x: auto;
  overflow-y: hidden;
  color: var(--fg-primary);
}

.inline-formula {
  color: var(--fg-primary);
  white-space: nowrap;
}

.copy-code {
  position: absolute;
  top: 0.55rem;
  right: 0.55rem;
  min-height: 44px;
  padding: 0.4rem 0.65rem;
  border: 1px solid var(--border-default);
  color: var(--fg-muted);
  background: var(--bg-raised);
  font-family: var(--font-data);
  font-size: 0.58rem;
  cursor: pointer;
}

.markdown-body pre:has(.copy-code) {
  padding-top: 3.55rem;
}

.copy-code:hover {
  color: var(--fg-primary);
  border-color: var(--brand);
}

.table-scroll {
  width: 100%;
  margin: 2rem 0 2.5rem;
  overflow-x: auto;
  border: 1px solid var(--border-default);
  scrollbar-width: thin;
  scrollbar-color: var(--border-emphasis) var(--bg-base);
}

.markdown-body table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  line-height: 1.5;
}

.markdown-body th,
.markdown-body td {
  padding: 0.75rem 0.85rem;
  border-right: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  text-align: left;
  vertical-align: top;
}

.markdown-body th:first-child,
.markdown-body td:first-child {
  width: 78px;
  min-width: 78px;
  white-space: nowrap;
}

.markdown-body table code {
  white-space: nowrap;
  overflow-wrap: normal;
  word-break: normal;
}

.markdown-body th {
  color: var(--fg-primary);
  background: var(--bg-overlay);
  font-family: var(--font-data);
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.markdown-body tr:nth-child(even) td {
  background: color-mix(in srgb, var(--bg-raised) 44%, transparent);
}

.doc-image {
  margin: 2.5rem 0 3.5rem;
}

.doc-image img {
  width: 100%;
  height: auto;
  border: 1px solid var(--border-default);
  background: var(--bg-raised);
}

.doc-image figcaption {
  padding-top: 0.65rem;
  color: var(--fg-muted);
  font-family: var(--font-data);
  font-size: 0.62rem;
}

.guide-error {
  padding: 2rem;
  border-left: 3px solid var(--data-temp);
  background: var(--bg-raised);
}

@media (max-width: 1180px) {
  .guide-rail-inner {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .guide-intro,
  .guide-page-title,
  .guide-page-lead {
    max-width: 760px;
  }

  .doc-tab {
    min-height: 124px;
  }
}

@media (max-width: 820px) {
  .reader-toolbar {
    grid-template-columns: minmax(0, 1fr) auto;
  }

  .reader-filter {
    grid-column: 1 / -1;
    grid-row: 2;
    margin-bottom: 0.8rem;
  }

  .reader-source {
    justify-self: end;
  }

  .reader-body {
    grid-template-columns: 1fr;
  }

  .chapter-rail {
    position: static;
    max-height: none;
    padding: 1rem var(--page-pad);
    border-right: 0;
    border-bottom: 1px solid var(--border-default);
  }

  .chapter-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    max-height: 230px;
    overflow-y: auto;
  }

  .markdown-body {
    width: 100%;
  }

  .markdown-body h1,
  .markdown-body h2,
  .markdown-body h3,
  .markdown-body h4 {
    scroll-margin-top: 145px;
  }
}

@media (max-width: 620px) {
  .guide-rail {
    padding-block: 3.5rem;
  }

  .guide-page-title {
    font-size: clamp(2.65rem, 13vw, 3.7rem);
  }

  .guide-doc-nav {
    grid-template-columns: 1fr;
  }

  .doc-tab {
    min-height: 94px;
    border-right: 0;
  }

  .reader-toolbar {
    min-height: 116px;
    padding-top: 0.55rem;
  }

  .reader-source {
    font-size: 0;
  }

  .reader-source svg {
    width: 18px;
    height: 18px;
  }

  .reader-filter {
    grid-template-columns: 44px minmax(0, 1fr);
    height: 44px;
  }

  .chapter-list {
    grid-template-columns: 1fr;
    max-height: 190px;
  }

  .chapter-list a[data-depth="3"] {
    padding-left: 1.4rem;
  }

  .markdown-body {
    padding: 3.5rem var(--page-pad) 6rem;
  }

  .markdown-body h1 {
    font-size: clamp(2.55rem, 12vw, 3.5rem);
  }

  .markdown-body h2 {
    margin-top: 4rem;
    font-size: clamp(1.9rem, 9vw, 2.7rem);
  }

  .markdown-body h1,
  .markdown-body h2,
  .markdown-body h3,
  .markdown-body h4 {
    scroll-margin-top: 170px;
  }

  .markdown-body pre {
    margin-inline: calc(var(--page-pad) * -1);
    border-right: 0;
    border-left-width: 0;
  }

  .markdown-body pre.formula-block {
    border-left-width: 3px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .guide-loading span::after {
    animation: none;
    transform: none;
  }
}