.docs-layout {
  width: min(1240px, calc(100% - 32px));
  display: grid;
  grid-template-columns: minmax(220px, 280px) minmax(0, 820px);
  gap: 2rem;
  align-items: start;
  justify-content: start;
}

.docs-sidebar {
  position: sticky;
  top: 5rem;
  max-height: calc(100vh - 6rem);
  overflow: auto;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow);
}

.docs-sidebar-toggle {
  display: none;
}

.docs-sidebar-backdrop {
  display: none;
}

.docs-sidebar-mobile-only {
  display: none;
}

.docs-sidebar-header {
  display: none;
}

.docs-nav-list {
  display: grid;
  gap: 0.35rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.docs-nav-list a {
  display: block;
  padding: 0.65rem 0.75rem;
  border-radius: 0.6rem;
  color: inherit;
  text-decoration: none;
}

.docs-nav-list a:hover {
  background: var(--accent);
}

.docs-nav-list a[aria-current="page"] {
  font-weight: 700;
  background: var(--accent);
  color: var(--primary);
}

.docs-content {
  width: 100%;
  max-width: none;
  min-height: calc(100vh - 1rem);
  min-width: 0;
  margin: 0;
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1rem;
}

.course-card {
  display: block;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  color: inherit;
  text-decoration: none;
  background: var(--surface);
}

.course-card:hover {
  transform: translateY(-2px);
}

.course-number {
  display: inline-block;
  margin-bottom: 0.5rem;
  font-size: 0.85rem;
  font-weight: 700;
  opacity: 0.7;
}

.lesson-list {
  display: grid;
  gap: 0.75rem;
}

.lesson-list-item {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
}

.lesson-list-item h3 {
  margin-top: 0;
}

.lesson-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.lesson-nav-link {
  display: grid;
  gap: 0.25rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  color: inherit;
  text-decoration: none;
  background: var(--surface);
}

.lesson-nav-link:hover {
  background: var(--accent);
}

.lesson-nav-next {
  text-align: right;
}

.lesson-nav-link span {
  font-size: 0.85rem;
  opacity: 0.7;
}

@media (max-width: 880px) {
  .docs-layout {
    display: block;
    /* padding-top: 3.75rem; */
  }

  .docs-sidebar {
    position: fixed;
    top: auto;
    right: 0.85rem;
    bottom: 0;
    left: 0.85rem;
    z-index: 60;
    width: auto;
    min-height: 0;
    max-height: min(72vh, 620px);
    margin: 0;
    padding: 0 1.1rem 1.25rem;
    overflow: auto;
    border-width: 1px 1px 0;
    border-radius: 1.1rem 1.1rem 0 0;
    box-shadow: 0 -18px 40px rgba(0, 0, 0, 0.24);
    transform: translateY(110%);
    transition: transform 180ms ease;
  }

  .docs-sidebar-mobile-only {
    display: block;
  }

  .docs-sidebar.is-open {
    transform: translateY(0);
  }

  .docs-sidebar-toggle {
    position: fixed;
    right: 1rem;
    bottom: 1.15rem;
    z-index: 70;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.75rem;
    min-height: 2.75rem;
    padding: 0;
    border: 1px solid var(--border);
    border-radius: 0.85rem;
    background: var(--surface);
    color: var(--text);
    box-shadow: var(--shadow);
    cursor: pointer;
    font-size: 0;
  }

  .docs-sidebar-toggle::before {
    content: "";
    width: 1.15rem;
    height: 2px;
    border-radius: 999px;
    background: currentColor;
    box-shadow:
      0 -0.38rem 0 currentColor,
      0 0.38rem 0 currentColor;
  }

  .docs-sidebar nav {
    display: block;
  }

  .docs-sidebar-header {
    position: sticky;
    top: 0;
    z-index: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    min-height: 4rem;
    margin: 0 -1.1rem 1rem;
    padding: 0 1.1rem;
    border-bottom: 1px solid var(--border);
    background: var(--surface);
    font-weight: 800;
  }

  .docs-sidebar-close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    min-height: 2.25rem;
    padding: 0;
    border: 0;
    border-radius: 0.65rem;
    background: transparent;
    color: var(--text);
    cursor: pointer;
    font-size: 1.8rem;
    line-height: 1;
  }

  .docs-sidebar-backdrop {
    position: fixed;
    inset: 0;
    z-index: 50;
    display: none;
    background: rgba(0, 0, 0, 0.48);
  }

  .docs-sidebar-backdrop.is-visible {
    display: block;
  }

  body.docs-sidebar-open {
    overflow: hidden;
  }
}

@media (max-width: 560px) {
  .lesson-nav {
    grid-template-columns: 1fr;
  }

  .lesson-nav-next {
    text-align: left;
  }
}

.docs-nav-sublist {
  display: grid;
  gap: 0.2rem;
  margin: 0.25rem 0 0.5rem;
  padding: 0 0 0 0.85rem;
  border-left: 2px solid var(--border);
  list-style: none;
}

.docs-nav-sublist a {
  padding: 0.48rem 0.65rem;
  font-size: 0.92rem;
}

.docs-nav-group:not(.is-current-group):not(.is-expanded) .docs-nav-sublist {
  display: none;
}

.figure-pair,
.step-image-grid {
  display: grid;
  gap: 1rem;
}

.figure-pair {
  grid-template-columns: 1fr;
}

.step-image-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 1rem;
}

.figure-pair figure,
.figure-single,
.step-image-grid .lesson-figure {
  margin: 0;
}

.lesson-figure {
  display: grid;
  gap: 0.5rem;
  margin: 1rem 0 0;
}

.lesson-figure img {
  display: block;
  width: 100%;
  max-width: 500px;
  height: auto;
  margin-inline: auto;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.lesson-figure.is-framed img {
  padding: 0.4rem;
  background: color-mix(in srgb, var(--surface) 88%, var(--accent) 12%);
}

.lesson-figure.is-compact img {
  width: auto;
  max-width: 100%;
  max-height: 450px;
}

.lesson-figure figcaption {
  max-width: 500px;
  margin: 0 auto;
  font-size: 0.9rem;
  line-height: 1.6;
  opacity: 0.8;
}

.figure-pair .lesson-figure img,
.figure-pair .lesson-figure figcaption,
.step-image-grid .lesson-figure img,
.step-image-grid .lesson-figure figcaption {
  max-width: 100%;
}

.step-media {
  margin: 1rem 0 1.35rem;
}

.step-media:first-of-type {
  margin-top: 0.75rem;
}

@media (max-width: 720px) {
  .step-image-grid {
    grid-template-columns: 1fr;
  }

  .lesson-figure img,
  .lesson-figure figcaption {
    max-width: 100%;
  }
}

/* I/O course cards */
.io-lesson-grid,
.concept-grid,
.wiring-compare,
.fault-grid,
.terminal-grid {
  display: grid;
  gap: 1rem;
}

.io-lesson-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.io-lesson-card,
.concept-card,
.wiring-card,
.fault-grid article,
.terminal-card,
.equation-card,
.circuit-demo,
.sensor-demo {
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: var(--surface);
}

.io-lesson-card {
  display: block;
  padding: 1.2rem;
  color: inherit;
  text-decoration: none;
}

.io-lesson-card:hover {
  transform: translateY(-2px);
}

.io-lesson-card h3,
.concept-card h3,
.wiring-card h3,
.fault-grid h3,
.terminal-card h3 {
  margin-top: 0;
}

.io-lesson-number,
.concept-label {
  display: inline-block;
  margin-bottom: 0.55rem;
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  opacity: 0.7;
}

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

.concept-grid-three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.concept-card {
  padding: 1.15rem;
}

.concept-example {
  margin-bottom: 0;
  font-size: 0.92rem;
}

.table-scroll {
  overflow-x: auto;
  border-radius: 0.75rem;
}

.equation-card {
  display: grid;
  gap: 0.35rem;
  padding: 1rem 1.1rem;
}

.equation-card strong {
  font-size: 0.88rem;
  opacity: 0.72;
}

.mode-switch {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-bottom: 1rem;
  padding: 0.3rem;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  background: var(--surface);
}

.mode-switch button {
  padding: 0.6rem 0.85rem;
  border: 0;
  border-radius: 0.55rem;
  background: transparent;
  color: inherit;
  cursor: pointer;
}

.mode-switch button.is-active {
  background: var(--accent);
  font-weight: 800;
}

.circuit-demo,
.sensor-demo {
  padding: 1.2rem;
}

.circuit-summary {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.circuit-tag {
  font-size: 0.9rem;
  opacity: 0.75;
}

.circuit-flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  margin: 1rem 0;
}

.circuit-node {
  padding: 0.55rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: 0.55rem;
  background: var(--surface-soft);
  font-size: 0.92rem;
}

.circuit-node.power {
  font-weight: 800;
}

.circuit-node.signal {
  border-width: 2px;
  font-weight: 800;
}

.circuit-node.common {
  font-weight: 700;
}

.circuit-arrow {
  font-weight: 800;
  opacity: 0.55;
}

.wiring-compare {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.wiring-card {
  padding: 1.1rem;
}

.wiring-card.single {
  max-width: 700px;
}

.wiring-code {
  overflow-x: auto;
  margin: 0 0 0.9rem;
  padding: 0.9rem;
  border-radius: 0.65rem;
  background: color-mix(in srgb, var(--surface) 86%, var(--primary) 14%);
  color: var(--text);
  white-space: pre;
}

.notice.warning {
  border-left: 4px solid currentColor;
}

.sensor-wire-list {
  display: grid;
  gap: 0.6rem;
}

.sensor-wire-list>div {
  display: grid;
  grid-template-columns: auto minmax(110px, auto) 1fr;
  align-items: center;
  gap: 0.55rem;
}

.wire-dot {
  width: 0.8rem;
  height: 0.8rem;
  border: 1px solid color-mix(in srgb, var(--text) 42%, transparent);
  border-radius: 999px;
}

.wire-dot.brown {
  background: #795548;
}

.wire-dot.blue {
  background: #1976d2;
}

.wire-dot.black {
  background: #222;
}

.wire-dot.purple {
  background: #7e57c2;
}

.fault-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.fault-grid article {
  padding: 1rem;
}

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

.terminal-card {
  padding: 1.1rem;
}

.terminal-list {
  display: grid;
  gap: 0.35rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.terminal-list li {
  display: grid;
  grid-template-columns: 4rem 1fr;
  align-items: center;
  gap: 0.7rem;
  padding: 0.42rem 0;
  border-bottom: 1px solid var(--border);
}

.terminal-list li:last-child {
  border-bottom: 0;
}

.terminal-list span {
  font-variant-numeric: tabular-nums;
  opacity: 0.68;
}

@media (max-width: 760px) {

  .io-lesson-grid,
  .concept-grid,
  .concept-grid-three,
  .wiring-compare,
  .fault-grid,
  .terminal-grid {
    grid-template-columns: 1fr;
  }

  .circuit-flow {
    align-items: stretch;
    flex-direction: column;
  }

  .circuit-arrow {
    transform: rotate(90deg);
    align-self: center;
  }
}

.manual-list {
  display: grid;
  gap: 1rem;
}

.manual-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1.2rem;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: var(--surface);
}

.manual-info {
  min-width: 0;
}

.manual-info h3 {
  margin: 0 0 0.45rem;
}

.manual-info p {
  margin: 0 0 0.65rem;
}

.manual-meta {
  font-size: 0.85rem;
  opacity: 0.65;
}

.manual-actions {
  display: flex;
  flex-shrink: 0;
  gap: 0.6rem;
}

@media (max-width: 650px) {
  .manual-card {
    align-items: stretch;
    flex-direction: column;
  }

  .manual-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .manual-actions .button {
    text-align: center;
  }
}
.fanuc-keyword {
  font-weight: 700;
}