:root {
  color-scheme: light;
  --bg: #f4efe4;
  --bg-strong: #e7ddca;
  --paper: rgba(255, 251, 245, 0.84);
  --paper-strong: rgba(255, 248, 239, 0.95);
  --ink: #172126;
  --muted: #52606a;
  --line: rgba(23, 33, 38, 0.14);
  --line-strong: rgba(23, 33, 38, 0.24);
  --accent: #0c6b63;
  --accent-strong: #094f49;
  --accent-soft: rgba(12, 107, 99, 0.12);
  --highlight: #bc5d1f;
  --shadow: 0 18px 60px rgba(23, 33, 38, 0.12);
  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 14px;
  --page-width: 1180px;
  --body-font: "Avenir Next", "Segoe UI", "Helvetica Neue", sans-serif;
  --display-font: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, serif;
  --mono-font: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--body-font);
  background:
    radial-gradient(circle at top left, rgba(12, 107, 99, 0.18), transparent 28%),
    radial-gradient(circle at bottom right, rgba(188, 93, 31, 0.14), transparent 24%),
    linear-gradient(180deg, #f7f1e7 0%, #efe7d8 100%);
  background-attachment: fixed;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(23, 33, 38, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 33, 38, 0.05) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.45), transparent 85%);
}

a {
  color: inherit;
}

img {
  max-width: 100%;
}

code,
pre {
  font-family: var(--mono-font);
}

.site-shell {
  width: min(var(--page-width), calc(100% - 32px));
  margin: 0 auto;
  padding: 28px 0 56px;
  position: relative;
}

.site-header,
.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.site-header {
  margin-bottom: 32px;
  padding: 18px 20px;
  border: 1px solid var(--line);
  background: rgba(255, 250, 243, 0.62);
  backdrop-filter: blur(12px);
  border-radius: 999px;
  box-shadow: var(--shadow);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background:
    linear-gradient(135deg, rgba(12, 107, 99, 0.9), rgba(188, 93, 31, 0.85));
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.brand-copy strong,
.brand-copy span {
  display: block;
}

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

.brand-copy span {
  font-size: 0.78rem;
  color: var(--muted);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.site-nav a {
  text-decoration: none;
  font-size: 0.94rem;
  color: var(--muted);
  padding: 10px 14px;
  border-radius: 999px;
  transition: background-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  background: var(--accent-soft);
  color: var(--accent-strong);
  transform: translateY(-1px);
}

.hero,
.page-hero,
.status-panel,
.section-card,
.topic-card,
.path-card,
.entry-card,
.status-card,
.resource-card,
.term-card,
.formula-card,
.timeline-card,
.trap-card,
.metric-card,
.chapter-nav,
.spotlight-card {
  border: 1px solid var(--line);
  background: var(--paper);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
}

.hero,
.page-hero {
  border-radius: var(--radius-lg);
  padding: 34px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.74rem;
  font-weight: 700;
}

.hero-grid,
.page-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(300px, 0.9fr);
  gap: 26px;
  align-items: start;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: var(--display-font);
  line-height: 0.98;
  font-weight: 700;
}

h1 {
  font-size: clamp(3rem, 7vw, 5.8rem);
  letter-spacing: -0.04em;
}

h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: -0.03em;
}

h3 {
  font-size: 1.28rem;
  line-height: 1.15;
}

.lede,
.section-intro,
.page-hero-copy p,
.hero-copy p,
.section-card p,
.topic-card p,
.entry-card p,
.status-card p,
.resource-card p,
.trap-card p,
.spotlight-card p {
  color: var(--muted);
  line-height: 1.75;
}

.hero-actions,
.section-actions,
.page-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 24px;
}

.button,
.ghost-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 18px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  border: 1px solid transparent;
}

.button {
  background: var(--accent);
  color: #fff;
}

.button:hover {
  background: var(--accent-strong);
}

.ghost-button {
  background: rgba(255, 255, 255, 0.55);
  border-color: var(--line);
  color: var(--ink);
}

button.button,
button.ghost-button {
  cursor: pointer;
  font: inherit;
}

button.button:disabled,
button.ghost-button:disabled {
  cursor: not-allowed;
  opacity: 0.65;
}

.hero-rail,
.chapter-nav,
.status-panel,
.formula-card,
.timeline-card {
  border-radius: var(--radius-md);
  padding: 24px;
}

.hero-rail ol,
.chapter-nav ol,
.checklist,
.mini-list,
.topic-points,
.resource-list,
.link-list {
  margin: 0;
  padding-left: 18px;
}

.hero-rail li,
.chapter-nav li,
.checklist li,
.mini-list li,
.topic-points li,
.resource-list li,
.link-list li {
  color: var(--muted);
  line-height: 1.7;
  margin-top: 8px;
}

.hero-rail li:first-child,
.chapter-nav li:first-child,
.checklist li:first-child,
.mini-list li:first-child,
.topic-points li:first-child,
.resource-list li:first-child,
.link-list li:first-child {
  margin-top: 0;
}

.strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 24px;
}

.entry-card,
.topic-card,
.path-card,
.status-card,
.resource-card,
.term-card,
.spotlight-card,
.trap-card,
.metric-card,
.section-card {
  border-radius: var(--radius-md);
  padding: 22px;
}

.entry-card strong,
.metric-card strong {
  display: block;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--highlight);
  margin-bottom: 10px;
}

.section {
  margin-top: 28px;
}

.section-header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 18px;
}

.section-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.topic-card {
  position: relative;
  overflow: hidden;
}

.topic-card::after {
  content: "";
  position: absolute;
  inset: auto -30px -30px auto;
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(12, 107, 99, 0.16), transparent 70%);
}

.topic-topline,
.meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.module-id,
.badge,
.difficulty {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.module-id,
.badge {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.difficulty {
  background: rgba(188, 93, 31, 0.12);
  color: #964815;
}

.chip-row,
.term-grid,
.metric-grid,
.resource-grid {
  display: grid;
  gap: 14px;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
}

.chip {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  font-size: 0.9rem;
}

.term-grid {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.term-card h3,
.metric-card h3,
.resource-card h3,
.trap-card h3,
.spotlight-card h3 {
  margin-bottom: 10px;
}

.term-card p,
.metric-card p {
  margin: 0;
}

.page-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 24px;
  margin-top: 24px;
}

.chapter-nav {
  position: sticky;
  top: 24px;
  align-self: start;
}

.chapter-nav p {
  margin: 0 0 14px;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.content-stack {
  display: grid;
  gap: 18px;
}

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

.formula-card pre,
.section-card pre {
  margin: 16px 0 0;
  padding: 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(20, 31, 36, 0.94);
  color: #f2efe8;
  overflow: auto;
  line-height: 1.6;
}

.math-inline,
.formula-inline {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border: 1px solid rgba(12, 107, 99, 0.14);
  border-radius: 999px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.92), rgba(248, 241, 230, 0.9));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.72);
  color: var(--ink);
  font-family: var(--mono-font);
  font-size: 0.92rem;
  max-width: 100%;
  vertical-align: middle;
}

.math-display {
  margin-top: 12px;
  padding: 16px 18px;
  border: 1px solid rgba(12, 107, 99, 0.16);
  border-radius: 18px;
  background:
    radial-gradient(circle at top right, rgba(12, 107, 99, 0.1), transparent 44%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(249, 243, 234, 0.94));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.72);
  color: var(--ink);
  overflow-x: auto;
}

.math-inline.math-ready,
.math-display.math-ready {
  font-family: var(--body-font);
}

.math-inline .katex {
  font-size: 1.02em;
}

.math-display .katex-display {
  margin: 0;
}

.math-display .katex {
  font-size: 1.08em;
}

.timeline {
  display: grid;
  gap: 14px;
}

.timeline-card {
  position: relative;
  padding-left: 56px;
}

.timeline-card::before {
  content: attr(data-step);
  position: absolute;
  left: 20px;
  top: 22px;
  width: 24px;
  height: 24px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 700;
}

.status-panel {
  margin-top: 28px;
}

.status-summary {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.status-card dt {
  margin: 0 0 8px;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.status-card dd {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 700;
}

.status-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--muted);
  flex-wrap: wrap;
}

.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 6px rgba(12, 107, 99, 0.14);
}

.status-error {
  color: #8e3d1c;
}

.site-footer {
  margin-top: 34px;
  padding: 18px 0 0;
  color: var(--muted);
}

.site-footer p {
  margin: 0;
}

.footer-links {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.footer-links a {
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--accent-strong);
}

.flow-diagram,
.sequence-diagram {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

.flow-row,
.sequence-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.flow-step,
.sequence-step,
.equation-card,
.table-card {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.72), rgba(250, 245, 237, 0.82));
  border-radius: var(--radius-sm);
  padding: 14px 16px;
}

.equation-card {
  position: relative;
  overflow: hidden;
}

.equation-card::after {
  content: "";
  position: absolute;
  inset: auto -36px -42px auto;
  width: 116px;
  height: 116px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(12, 107, 99, 0.14), transparent 70%);
  pointer-events: none;
}

.flow-step,
.sequence-step {
  min-width: 160px;
  flex: 1 1 160px;
}

.flow-step strong,
.sequence-step strong,
.equation-card strong {
  display: block;
  margin-bottom: 6px;
  font-size: 0.84rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent-strong);
}

.flow-arrow {
  color: var(--highlight);
  font-weight: 700;
  font-size: 1.1rem;
}

.equation-grid,
.compare-grid,
.concept-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.equation-card p,
.table-card p,
.flow-step p,
.sequence-step p {
  margin: 0;
  color: var(--muted);
  line-height: 1.65;
}

.equation-card .formula-inline,
.equation-card .math-inline,
.equation-card .math-display {
  margin-top: 10px;
}

.table-card table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 12px;
  font-size: 0.95rem;
}

.table-card th,
.table-card td {
  border-top: 1px solid var(--line);
  padding: 10px 8px;
  text-align: left;
  vertical-align: top;
  color: var(--muted);
}

.table-card th {
  color: var(--ink);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.summary-card {
  border-radius: var(--radius-md);
  padding: 20px;
  border: 1px solid var(--line);
  background: var(--paper);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
}

.summary-card h3,
.summary-card p {
  margin: 0;
}

.summary-card p {
  margin-top: 10px;
  color: var(--muted);
  line-height: 1.7;
}

.summary-card .badge {
  margin-bottom: 12px;
}

.chapter-index {
  display: grid;
  gap: 18px;
}

.chapter-index-card {
  display: grid;
  grid-template-columns: 140px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  border-radius: var(--radius-md);
  padding: 22px;
  border: 1px solid var(--line);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.chapter-index-card .module-id {
  justify-content: center;
  min-height: 42px;
  font-size: 0.9rem;
}

.chapter-index-card p {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.75;
}

.visual-grid {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

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

.visual-card {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.72), rgba(250, 245, 237, 0.82));
  box-shadow: var(--shadow);
}

.visual-card img {
  display: block;
  width: 100%;
  height: auto;
}

.visual-card figcaption {
  padding: 14px 16px 16px;
  color: var(--muted);
  line-height: 1.65;
}

.chapter-index-card .link-list {
  margin-top: 12px;
}

.diagram-caption {
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.95rem;
}

.auth-shell {
  max-width: 760px;
  margin: 0 auto;
}

.auth-card {
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: rgba(255, 250, 243, 0.7);
  padding: 24px;
}

.auth-form {
  margin-top: 18px;
  display: grid;
  gap: 10px;
}

.auth-actions {
  margin-top: 18px;
  display: grid;
  gap: 10px;
}

.auth-google-button {
  display: inline-flex;
  justify-content: center;
  text-decoration: none;
}

.auth-note {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.admin-shell {
  display: grid;
  gap: 18px;
}

.admin-hero {
  display: grid;
  gap: 18px;
}

.admin-summary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.admin-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  color: var(--muted);
}

.admin-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.admin-grid-wide {
  grid-template-columns: 1fr;
}

.admin-card {
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: rgba(255, 250, 243, 0.72);
  padding: 22px;
  display: grid;
  gap: 14px;
}

.admin-card-header {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 12px;
}

.admin-summary-grid .admin-card {
  align-content: start;
}

.admin-summary-grid .admin-card-header {
  min-height: 128px;
}

.admin-summary-grid .admin-card-header > div {
  min-width: 0;
}

.admin-summary-grid .admin-stat-grid,
.admin-summary-grid .admin-link-grid {
  align-self: start;
}

.admin-card p {
  margin: 0;
}

.admin-card-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.admin-note {
  margin: 0;
  color: var(--muted);
}

.admin-note-good {
  color: var(--accent-strong);
}

.admin-note-warn {
  color: #8e6a1c;
}

.admin-note-bad {
  color: #8e3d1c;
}

.admin-stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.admin-stat {
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.58);
  padding: 14px;
}

.admin-stat dt {
  margin: 0 0 8px;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.admin-stat dd {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 700;
}

.admin-kv-list {
  display: grid;
  gap: 12px;
  margin: 0;
}

.admin-kv-row {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.admin-kv-row:first-child {
  padding-top: 0;
  border-top: 0;
}

.admin-kv-row dt {
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 700;
}

.admin-kv-row dd {
  margin: 0;
}

.admin-table-wrap {
  overflow: auto;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.admin-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 640px;
}

.admin-table-docker {
  min-width: 1240px;
}

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

.admin-table th {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.admin-cell-meta {
  display: block;
  margin-top: 6px;
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.35;
}

.admin-cell-metric {
  font-family: var(--mono-font);
  font-size: 0.84rem;
  color: var(--ink);
}

.admin-pill {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.62);
  font-size: 0.82rem;
  font-weight: 700;
}

.admin-pill-good {
  background: rgba(12, 107, 99, 0.12);
  border-color: rgba(12, 107, 99, 0.24);
  color: var(--accent-strong);
}

.admin-pill-warn {
  background: rgba(188, 93, 31, 0.12);
  border-color: rgba(188, 93, 31, 0.24);
  color: #964815;
}

.admin-pill-bad {
  background: rgba(142, 61, 28, 0.12);
  border-color: rgba(142, 61, 28, 0.24);
  color: #8e3d1c;
}

.admin-pill-neutral {
  color: var(--ink);
}

.admin-link-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.admin-link-card {
  display: grid;
  gap: 6px;
  padding: 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.58);
  text-decoration: none;
}

.admin-link-card strong {
  font-size: 0.96rem;
}

.admin-link-card span {
  color: var(--muted);
  font-size: 0.86rem;
}

.admin-link-card:hover {
  border-color: rgba(12, 107, 99, 0.28);
  transform: translateY(-1px);
}

.admin-action-section {
  display: grid;
  gap: 10px;
}

.admin-action-section h4 {
  margin: 0;
  font-size: 0.92rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.admin-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.admin-log {
  margin: 0;
  min-height: 380px;
  max-height: 620px;
  overflow: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(20, 31, 36, 0.94);
  color: #f2efe8;
  padding: 16px;
  line-height: 1.55;
}

.form-label {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--muted);
}

.text-input,
.playground-code {
  width: 100%;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, 0.8);
  color: var(--ink);
  font: inherit;
}

.text-input {
  min-height: 44px;
  padding: 10px 12px;
}

.form-error {
  margin: 2px 0 0;
  color: #8e3d1c;
  min-height: 20px;
  font-size: 0.9rem;
}

.assessment-shell {
  border-radius: 22px;
  border: 1px solid rgba(16, 22, 31, 0.35);
  background: linear-gradient(180deg, #202632 0%, #171c26 100%);
  box-shadow: 0 28px 70px rgba(16, 22, 31, 0.35);
  padding: 18px;
  color: #d8e0ea;
}

.assessment-shell h2,
.assessment-shell h3,
.assessment-shell p {
  color: inherit;
}

.assessment-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.assessment-topbar .eyebrow {
  color: #83b7f8;
  margin-bottom: 8px;
}

.assessment-runtime-note {
  margin: 10px 0 0;
  color: #98abc3;
  font-family: var(--mono-font);
  font-size: 0.85rem;
}

.assessment-badges {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.assessment-badge {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  border: 1px solid rgba(138, 155, 178, 0.28);
  background: rgba(31, 42, 56, 0.75);
  color: #a8bbd1;
  font-family: var(--mono-font);
  font-size: 0.77rem;
}

.playground-grid {
  margin-top: 14px;
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(340px, 1fr);
  gap: 12px;
  align-items: stretch;
}

.playground-panel {
  min-width: 0;
  border: 1px solid rgba(138, 155, 178, 0.24);
  border-radius: 14px;
  background: #121822;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.playground-panel-editor {
  grid-column: 1;
  order: 1;
}

.playground-panel-output {
  grid-column: 2;
  order: 2;
}

.playground-note {
  margin: 0;
  padding: 10px 12px 0;
  color: #98abc3;
  font-family: var(--mono-font);
  font-size: 0.9rem;
}

.ide-shell {
  margin-top: 10px;
  border-radius: 22px;
  border: 1px solid rgba(16, 22, 31, 0.35);
  background: linear-gradient(180deg, #202632 0%, #171c26 100%);
  box-shadow: 0 28px 70px rgba(16, 22, 31, 0.35);
  padding: 18px;
  color: #d8e0ea;
}

.ide-shell h2,
.ide-shell h3,
.ide-shell p {
  color: inherit;
}

.ide-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.ide-branding .eyebrow {
  color: #83b7f8;
  margin-bottom: 8px;
}

.ide-branding h2 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  letter-spacing: -0.03em;
}

.ide-runbar {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.ide-shell .button,
.assessment-shell .button {
  background: #7bcd7a;
  color: #0f1a11;
}

.ide-shell .button:hover,
.assessment-shell .button:hover {
  background: #69bd68;
}

.ide-shell .ghost-button,
.assessment-shell .ghost-button {
  border-color: rgba(216, 224, 234, 0.2);
  color: #d8e0ea;
  background: rgba(37, 46, 60, 0.65);
}

.ide-status {
  margin: 14px 0 0;
  font-size: 0.95rem;
  color: #9db0c7;
}

.ide-status::before {
  content: "";
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-right: 10px;
  background: #5ed39b;
  box-shadow: 0 0 0 5px rgba(94, 211, 155, 0.18);
}

.ide-status.status-error {
  color: #e7a28e;
}

.ide-status.status-error::before {
  background: #d07053;
  box-shadow: 0 0 0 5px rgba(208, 112, 83, 0.2);
}

.ide-workspace {
  margin-top: 14px;
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: 0;
  border: 1px solid rgba(138, 155, 178, 0.24);
  border-radius: 14px;
  overflow: hidden;
}

.ide-sidebar {
  background: linear-gradient(180deg, #2a3040 0%, #222838 100%);
  border-right: 1px solid rgba(138, 155, 178, 0.22);
  padding: 14px 12px;
  display: grid;
  gap: 16px;
  align-content: start;
}

.ide-sidebar-title {
  margin: 0 0 8px;
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: #9cb0c9;
}

.ide-badge-list,
.ide-files {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.ide-badge-list li {
  font-size: 0.85rem;
  color: #d8e0ea;
  border: 1px solid rgba(138, 155, 178, 0.26);
  border-radius: 999px;
  padding: 6px 10px;
  background: rgba(58, 74, 96, 0.45);
}

.ide-files li {
  font-size: 0.9rem;
  color: #c6d2e1;
  border-radius: 8px;
  padding: 6px 8px;
}

.ide-files li:first-child {
  background: rgba(123, 205, 122, 0.14);
  color: #d7f2d6;
}

.ide-editor-pane {
  background: #131a24;
  padding: 0;
}

.ide-editor-head,
.editor-head,
.playground-output-head {
  min-height: 52px;
  padding: 10px 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  border-bottom: 1px solid rgba(138, 155, 178, 0.2);
}

.editor-head h3,
.playground-output-head h3 {
  color: #d8e0ea;
}

.ide-editor-head p {
  margin: 0;
  color: #98abc3;
  font-family: var(--mono-font);
  font-size: 0.9rem;
}

.playground-output-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.playground-output-actions .button,
.playground-output-actions .ghost-button {
  min-height: 36px;
  padding: 0 12px;
}

.editor-frame {
  background: linear-gradient(180deg, #111823 0%, #0d141e 100%);
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  min-height: 430px;
}

.editor-gutter {
  border-right: 1px solid rgba(138, 155, 178, 0.2);
  color: #7e92ae;
  font-family: var(--mono-font);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding-top: 14px;
  text-align: center;
  background: rgba(255, 255, 255, 0.02);
}

.playground-code {
  margin: 0;
  min-height: 430px;
  resize: vertical;
  border: 0;
  border-radius: 0;
  background: transparent;
  color: #dbe3ee;
  padding: 14px;
  font-family: var(--mono-font);
  line-height: 1.6;
  font-size: 0.95rem;
}

.playground-code:focus {
  outline: none;
}

.ide-output-pane {
  margin-top: 12px;
  border: 1px solid rgba(138, 155, 178, 0.22);
  border-radius: 14px;
  background: #121822;
  overflow: hidden;
}

.run-summary {
  padding: 10px 12px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.playground-meta {
  margin: 10px 0 0;
  padding: 0 12px;
  color: #9db0c7;
}

.playground-meta .status-dot {
  background: #5ed39b;
  box-shadow: 0 0 0 5px rgba(94, 211, 155, 0.18);
}

.playground-meta .status-error {
  color: #efb8a8;
}

.run-chip {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  border: 1px solid rgba(138, 155, 178, 0.28);
  background: rgba(31, 42, 56, 0.75);
  color: #a8bbd1;
  font-family: var(--mono-font);
  font-size: 0.77rem;
}

.run-chip-alert {
  background: rgba(208, 112, 83, 0.2);
  border-color: rgba(208, 112, 83, 0.48);
  color: #efb8a8;
}

.playground-output {
  margin: 10px 12px 12px;
  min-height: 240px;
  max-height: 420px;
  overflow: auto;
  border-radius: 10px;
  border: 1px solid rgba(138, 155, 178, 0.26);
  background: #0b1119;
  color: #d0d9e4;
  padding: 12px;
  line-height: 1.6;
}

@media (max-width: 980px) {
  .hero-grid,
  .page-hero-grid,
  .page-layout,
  .admin-summary-grid,
  .topic-grid,
  .section-grid,
  .term-grid,
  .note-grid,
  .metric-grid,
  .resource-grid,
  .status-summary,
  .strip,
  .summary-grid,
  .equation-grid,
  .compare-grid,
  .concept-grid {
    grid-template-columns: 1fr;
  }

  .chapter-nav {
    position: static;
  }

  .chapter-index-card {
    grid-template-columns: 1fr;
  }

  .visual-grid-double {
    grid-template-columns: 1fr;
  }

  .ide-topbar {
    flex-direction: column;
    align-items: flex-start;
  }

  .assessment-topbar {
    flex-direction: column;
    align-items: flex-start;
  }

  .ide-workspace {
    grid-template-columns: 1fr;
  }

  .ide-sidebar {
    border-right: 0;
    border-bottom: 1px solid rgba(138, 155, 178, 0.22);
  }
}

@media (max-width: 720px) {
  .site-shell {
    width: min(100% - 20px, var(--page-width));
    padding-top: 18px;
  }

  .site-header,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-header {
    border-radius: 28px;
  }

  .hero,
  .page-hero {
    padding: 26px 22px;
  }

  .section-card,
  .topic-card,
  .entry-card,
  .status-card,
  .resource-card,
  .term-card,
  .spotlight-card,
  .trap-card,
  .metric-card,
  .summary-card {
    padding: 18px;
  }

  .ide-shell {
    padding: 14px;
  }

  .flow-row,
  .sequence-row {
    align-items: stretch;
  }

  .flow-arrow {
    display: none;
  }

  .assessment-shell {
    padding: 14px;
  }

  .playground-grid {
    grid-template-columns: 1fr;
  }

  .admin-grid {
    grid-template-columns: 1fr;
  }

  .admin-kv-row {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .admin-stat-grid,
  .admin-link-grid {
    grid-template-columns: 1fr;
  }

  .playground-panel-editor,
  .playground-panel-output {
    grid-column: auto;
  }

  .editor-frame,
  .playground-code,
  .playground-output {
    min-height: 300px;
  }

  .ide-runbar {
    width: 100%;
  }

  .ide-runbar .button,
  .ide-runbar .ghost-button {
    flex: 1;
  }

  .playground-output-head {
    flex-direction: column;
    align-items: flex-start;
  }

  .playground-output-actions {
    width: 100%;
  }

  .playground-output-actions .button,
  .playground-output-actions .ghost-button {
    flex: 1;
  }
}