:root {
  color-scheme: dark;
  --bg: #05070b;
  --bg-elev: #090d13;
  --surface: rgba(13, 18, 27, 0.78);
  --surface-solid: #0d121b;
  --surface-2: #111824;
  --surface-3: #172130;
  --text: #f5f7fb;
  --muted: #9aa8bc;
  --muted-2: #6f7d91;
  --line: rgba(164, 187, 220, 0.15);
  --line-strong: rgba(164, 187, 220, 0.28);
  --accent: #5eead4;
  --accent-2: #38bdf8;
  --accent-3: #a78bfa;
  --accent-soft: rgba(94, 234, 212, 0.12);
  --danger: #fb7185;
  --warning: #fbbf24;
  --success: #4ade80;
  --shadow: 0 28px 90px rgba(0, 0, 0, 0.42);
  --radius: 22px;
  --radius-sm: 13px;
  --header-h: 72px;
  --content: 1220px;
  --font-sans:
    Inter, "Segoe UI Variable", "Segoe UI", system-ui, -apple-system,
    BlinkMacSystemFont, sans-serif;
  --font-mono:
    "Cascadia Code", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --syntax-keyword: #c084fc;
  --syntax-function: #67e8f9;
  --syntax-string: #86efac;
  --syntax-number: #fbbf24;
  --syntax-comment: #718096;
  --syntax-name: #93c5fd;
  --syntax-operator: #fda4af;
  --code-bg: #080b11;
  --code-head-start: #151b26;
  --code-head-end: #10151e;
  --code-head-text: #94a3b8;
  --code-border: rgba(255, 255, 255, 0.09);
  --code-text: #d8e3ef;
  --code-line-number: #46556a;
  --code-copy-bg: #171e2a;
  --code-copy-border: rgba(255, 255, 255, 0.1);
  --code-copy-hover: #ffffff;
  --code-shadow: 0 18px 50px rgba(0, 0, 0, 0.22);
}
html[data-theme="light"] {
  color-scheme: light;
  --bg: #f4f7fb;
  --bg-elev: #ffffff;
  --surface: rgba(255, 255, 255, 0.82);
  --surface-solid: #ffffff;
  --surface-2: #f7f9fc;
  --surface-3: #eef3f9;
  --text: #101722;
  --muted: #536176;
  --muted-2: #778398;
  --line: rgba(27, 48, 75, 0.13);
  --line-strong: rgba(27, 48, 75, 0.24);
  --accent: #0f9f8b;
  --accent-2: #0284c7;
  --accent-3: #7c3aed;
  --accent-soft: rgba(15, 159, 139, 0.1);
  --shadow: 0 28px 80px rgba(44, 62, 90, 0.14);
  --syntax-keyword: #7c3aed;
  --syntax-function: #0369a1;
  --syntax-string: #15803d;
  --syntax-number: #b45309;
  --syntax-comment: #64748b;
  --syntax-name: #1d4ed8;
  --syntax-operator: #be123c;
  --code-bg: #f8fafc;
  --code-head-start: #ffffff;
  --code-head-end: #f1f5f9;
  --code-head-text: #526176;
  --code-border: rgba(15, 23, 42, 0.13);
  --code-text: #1e293b;
  --code-line-number: #94a3b8;
  --code-copy-bg: #ffffff;
  --code-copy-border: rgba(15, 23, 42, 0.13);
  --code-copy-hover: #0f172a;
  --code-shadow: 0 18px 44px rgba(51, 65, 85, 0.12);
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 28px);
}
body {
  margin: 0;
  min-width: 320px;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -3;
  background:
    radial-gradient(circle at 18% 8%, rgba(56, 189, 248, 0.1), transparent 28%),
    radial-gradient(
      circle at 86% 18%,
      rgba(167, 139, 250, 0.08),
      transparent 30%
    ),
    radial-gradient(
      circle at 52% 92%,
      rgba(94, 234, 212, 0.07),
      transparent 34%
    );
}
a {
  color: inherit;
  text-decoration: none;
}
button,
input,
select {
  font: inherit;
}
button {
  color: inherit;
}
svg {
  width: 1.1em;
  height: 1.1em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}
img {
  max-width: 100%;
}
::selection {
  background: rgba(94, 234, 212, 0.28);
  color: var(--text);
}
.site-grid {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -2;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.55), transparent 72%);
  opacity: 0.35;
}
.skip-link {
  position: fixed;
  left: 16px;
  top: -60px;
  z-index: 1000;
  padding: 10px 14px;
  background: var(--text);
  color: var(--bg);
  border-radius: 10px;
  transition: 0.2s;
}
.skip-link:focus {
  top: 12px;
}
.section-shell {
  width: min(calc(100% - 40px), var(--content));
  margin-inline: auto;
}
.section-block {
  padding-block: 96px;
}
.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.kicker {
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.84rem;
}
.sr-only {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(20px) saturate(1.4);
  transition: 0.25s;
}
.site-header.is-scrolled {
  border-color: var(--line);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.12);
}
.header-inner {
  width: min(calc(100% - 32px), 1320px);
  height: 100%;
  margin: auto;
  display: flex;
  align-items: center;
  gap: 28px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: max-content;
}
.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  color: #05100d;
  background: linear-gradient(145deg, var(--accent), var(--accent-2));
  border-radius: 11px;
  box-shadow: 0 0 30px rgba(94, 234, 212, 0.16);
}
.brand-mark svg {
  width: 23px;
  height: 23px;
  stroke-width: 1.7;
}
.brand-copy {
  display: grid;
  line-height: 1.15;
}
.brand-copy strong {
  font-size: 0.95rem;
  letter-spacing: -0.02em;
}
.brand-copy small {
  margin-top: 4px;
  color: var(--muted);
  font-size: 0.66rem;
  font-family: var(--font-mono);
}
.desktop-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}
.desktop-nav a {
  padding: 9px 12px;
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 650;
  border-radius: 9px;
  transition: 0.2s;
}
.desktop-nav a:hover,
.desktop-nav a.is-active {
  color: var(--text);
  background: var(--surface-2);
}
.header-actions {
  display: flex;
  gap: 8px;
}
.icon-button {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 11px;
  cursor: pointer;
  transition: 0.2s;
}
.icon-button:hover {
  border-color: var(--line-strong);
  transform: translateY(-1px);
}
.mobile-menu-button {
  display: none;
}
.mobile-nav {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  left: 16px;
  right: 16px;
  padding: 10px;
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: var(--shadow);
}
.mobile-nav.is-open {
  display: grid;
}
.mobile-nav a {
  padding: 12px;
  border-radius: 10px;
  color: var(--muted);
}
.mobile-nav a:hover {
  background: var(--surface-2);
  color: var(--text);
}
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 46px;
  padding: 0 18px;
  border: 1px solid transparent;
  border-radius: 12px;
  font-weight: 750;
  font-size: 0.9rem;
  cursor: pointer;
  transition: 0.22s ease;
}
.button:hover {
  transform: translateY(-2px);
}
.button.primary {
  color: #04110e;
  background: linear-gradient(135deg, var(--accent), #8af7dd);
  box-shadow: 0 14px 34px rgba(94, 234, 212, 0.12);
}
.button.secondary {
  color: var(--text);
  border-color: var(--line-strong);
  background: var(--surface);
}
.button.compact {
  min-height: 38px;
  padding: 0 13px;
  font-size: 0.8rem;
}
.hero {
  min-height: calc(100svh - var(--header-h));
  display: grid;
  align-items: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}
.hero-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(380px, 0.92fr);
  align-items: center;
  gap: 44px;
  padding-block: 72px 88px;
}
.hero-copy {
  position: relative;
  z-index: 3;
}
.hero-copy h1 {
  margin: 0;
  max-width: 820px;
  font-size: clamp(3.2rem, 7.2vw, 7.3rem);
  line-height: 0.92;
  letter-spacing: -0.075em;
  font-weight: 720;
}
.hero-copy h1 span {
  display: block;
  color: transparent;
  background: linear-gradient(
    90deg,
    var(--accent),
    var(--accent-2) 46%,
    var(--accent-3)
  );
  -webkit-background-clip: text;
  background-clip: text;
}
.hero-lead {
  max-width: 720px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 1.8vw, 1.25rem);
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 30px;
  margin-top: 36px;
  color: var(--muted);
  font-size: 0.82rem;
}
.hero-meta span {
  display: flex;
  align-items: center;
  gap: 8px;
}
.hero-meta i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 14px var(--accent);
}
.hero-visual {
  position: relative;
  min-height: 570px;
  border: 1px solid var(--line);
  border-radius: 30px;
  overflow: hidden;
  background: linear-gradient(
    160deg,
    rgba(16, 23, 34, 0.82),
    rgba(5, 8, 13, 0.58)
  );
  box-shadow: var(--shadow);
}
html[data-theme="light"] .hero-visual {
  background: linear-gradient(
    160deg,
    rgba(255, 255, 255, 0.94),
    rgba(235, 242, 250, 0.72)
  );
}
.hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}
.hero-visual::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 55%, rgba(5, 7, 11, 0.72));
}
html[data-theme="light"] .hero-visual::before {
  background: linear-gradient(
    180deg,
    transparent 55%,
    rgba(244, 247, 251, 0.84)
  );
}
.hero-query-card {
  position: absolute;
  z-index: 3;
  left: 24px;
  right: 24px;
  bottom: 24px;
  padding: 18px;
  border: 1px solid var(--line-strong);
  border-radius: 17px;
  background: color-mix(in srgb, var(--surface-solid) 84%, transparent);
  backdrop-filter: blur(16px);
}
.query-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
}
.query-dots {
  display: flex;
  gap: 6px;
}
.query-dots i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--muted-2);
}
.query-dots i:first-child {
  background: #fb7185;
}
.query-dots i:nth-child(2) {
  background: #fbbf24;
}
.query-dots i:nth-child(3) {
  background: #4ade80;
}
.hero-query-card pre {
  margin: 14px 0 0;
  white-space: pre-wrap;
  color: #dce8f6;
  font: 500 0.79rem/1.7 var(--font-mono);
}
html[data-theme="light"] .hero-query-card pre {
  color: #1f334a;
}
.token-keyword {
  color: var(--syntax-keyword);
}
.token-function {
  color: var(--syntax-function);
}
.token-string {
  color: var(--syntax-string);
}
.token-number {
  color: var(--syntax-number);
}
.token-comment {
  color: var(--syntax-comment);
  font-style: italic;
}
.token-name {
  color: var(--syntax-name);
}
.token-operator {
  color: var(--syntax-operator);
}
.stats-strip {
  position: relative;
  z-index: 3;
  margin-top: -34px;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow);
}
.stat {
  padding: 24px 28px;
  border-right: 1px solid var(--line);
}
.stat:last-child {
  border-right: 0;
}
.stat strong {
  display: block;
  font-size: 1.55rem;
  letter-spacing: -0.04em;
}
.stat span {
  color: var(--muted);
  font-size: 0.78rem;
}
.intro-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 34px;
  align-items: start;
}
.section-heading h2 {
  margin: 0;
  max-width: 850px;
  font-size: clamp(2.2rem, 5vw, 4.5rem);
  line-height: 1.02;
  letter-spacing: -0.055em;
}
.section-heading p:not(.eyebrow) {
  max-width: 680px;
  color: var(--muted);
  font-size: 1.04rem;
}
.prereq-card {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(145deg, var(--surface), var(--surface-2));
}
.prereq-card h3 {
  margin: 0 0 12px;
  font-size: 1.25rem;
}
.prereq-card ul {
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
  list-style: none;
}
.prereq-card li {
  display: flex;
  gap: 10px;
  color: var(--muted);
}
.prereq-card li::before {
  content: "";
  width: 7px;
  height: 7px;
  margin-top: 0.55em;
  border-radius: 50%;
  background: var(--accent);
  flex: none;
}
.roadmap-shell {
  padding-block: 96px;
  border-block: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg-elev) 65%, transparent);
}
.roadmap-head {
  display: flex;
  justify-content: space-between;
  gap: 28px;
  align-items: end;
  margin-bottom: 38px;
}
.roadmap-head > p {
  max-width: 560px;
  margin: 0;
  color: var(--muted);
}
.roadmap {
  display: grid;
  gap: 12px;
  counter-reset: stage;
}
.stage-row {
  position: relative;
  display: grid;
  grid-template-columns: 88px 260px 1fr 48px;
  gap: 18px;
  align-items: center;
  min-height: 104px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  transition: 0.25s;
}
.stage-row:hover {
  border-color: var(--line-strong);
  transform: translateX(4px);
}
.stage-number {
  width: 56px;
  height: 56px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 16px;
  font: 700 0.88rem var(--font-mono);
  color: var(--accent);
  background: var(--surface-2);
}
.stage-title small {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}
.stage-title h3 {
  margin: 4px 0 0;
  font-size: 1.08rem;
}
.stage-courses {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}
.stage-courses span,
.stage-courses a {
  padding: 6px 9px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.72rem;
  background: var(--surface-2);
}
.stage-courses a {
  transition: 0.2s;
}
.stage-courses a.is-available {
  border-color: color-mix(in srgb, var(--accent) 42%, var(--line));
  color: var(--text);
  background: var(--accent-soft);
}
.stage-courses a:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}
.stage-arrow {
  color: var(--muted);
}
.catalogue-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 28px;
}
.catalogue-head > p {
  max-width: 570px;
  color: var(--muted);
}
.course-toolbar {
  position: sticky;
  top: calc(var(--header-h) + 12px);
  z-index: 20;
  display: grid;
  grid-template-columns: minmax(260px, 1fr) auto auto;
  gap: 10px;
  padding: 12px;
  margin-bottom: 32px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: blur(20px);
}
.search-box {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--surface-solid);
  color: var(--muted);
}
.search-box input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--text);
}
.search-box input::placeholder {
  color: var(--muted-2);
}
.filter-select {
  min-height: 44px;
  padding: 0 36px 0 13px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--surface-solid);
  color: var(--text);
  cursor: pointer;
}
.course-stage {
  margin-top: 60px;
}
.course-stage:first-of-type {
  margin-top: 0;
}
.stage-heading {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}
.stage-heading span {
  font: 700 0.78rem var(--font-mono);
  color: var(--accent);
  border: 1px solid var(--line);
  padding: 7px 9px;
  border-radius: 9px;
}
.stage-heading h3 {
  margin: 0;
  font-size: 1.3rem;
}
.stage-heading p {
  margin: 0 0 0 auto;
  color: var(--muted);
  font-size: 0.8rem;
}
.course-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}
.course-card {
  position: relative;
  min-height: 280px;
  display: flex;
  flex-direction: column;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 19px;
  background: linear-gradient(
    155deg,
    var(--surface),
    color-mix(in srgb, var(--surface-2) 68%, transparent)
  );
  overflow: hidden;
  transition: 0.25s;
}
.course-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  pointer-events: none;
  background: radial-gradient(
    circle at 90% 0,
    rgba(94, 234, 212, 0.09),
    transparent 32%
  );
  opacity: 0.7;
}
.course-card:hover {
  transform: translateY(-5px);
  border-color: var(--line-strong);
  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.14);
}
.course-top {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 12px;
  position: relative;
}
.course-number {
  font: 650 0.7rem var(--font-mono);
  color: var(--muted);
}
.course-glyph {
  display: inline-grid;
  place-items: center;
  min-width: 48px;
  height: 34px;
  padding: 0 10px;
  border: 1px solid var(--line-strong);
  border-radius: 9px;
  background: var(--surface-2);
  font: 750 0.66rem var(--font-mono);
  letter-spacing: 0.04em;
  color: var(--accent);
}
.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin-top: 20px;
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 750;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.status-pill i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--muted-2);
}
.status-pill.available {
  color: var(--success);
}
.status-pill.available i {
  background: var(--success);
  box-shadow: 0 0 10px rgba(74, 222, 128, 0.55);
}
.status-pill.legacy {
  color: var(--warning);
}
.course-card h4 {
  position: relative;
  margin: 11px 0 9px;
  font-size: 1.26rem;
  line-height: 1.18;
  letter-spacing: -0.025em;
}
.course-card p {
  position: relative;
  margin: 0;
  color: var(--muted);
  font-size: 0.86rem;
}
.card-meta {
  position: relative;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: auto;
  padding-top: 22px;
}
.card-meta span {
  padding: 5px 8px;
  border-radius: 7px;
  background: var(--surface-2);
  color: var(--muted);
  font-size: 0.67rem;
}
.card-action {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 17px;
  padding-top: 15px;
  border-top: 1px solid var(--line);
  font-size: 0.78rem;
  font-weight: 750;
  color: var(--muted);
}
.course-card.available .card-action {
  color: var(--accent);
}
.course-card[hidden],
.course-stage[hidden] {
  display: none !important;
}
.empty-state {
  display: none;
  padding: 40px;
  text-align: center;
  border: 1px dashed var(--line-strong);
  border-radius: 18px;
  color: var(--muted);
}
.empty-state.is-visible {
  display: block;
}
.method-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 34px;
}
.method-card {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}
.method-card span {
  font: 700 0.72rem var(--font-mono);
  color: var(--accent);
}
.method-card h3 {
  margin: 15px 0 8px;
}
.method-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}
.support-section {
  padding-block: 96px;
}
.support-grid {
  display: grid;
  grid-template-columns: 1fr 0.82fr;
  gap: 30px;
  align-items: center;
  padding: 38px;
  border: 1px solid var(--line);
  border-radius: 26px;
  background: linear-gradient(145deg, var(--surface), var(--surface-2));
  box-shadow: var(--shadow);
}
.support-grid h2 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.5rem);
  line-height: 1.02;
  letter-spacing: -0.05em;
}
.support-grid > div > p:not(.eyebrow) {
  color: var(--muted);
  max-width: 650px;
}
.social-row {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-top: 23px;
}
.social-row a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 9px;
  color: var(--muted);
  font-size: 0.76rem;
}
.social-row a:hover {
  color: var(--text);
  border-color: var(--line-strong);
}
.donation-card {
  padding: 24px;
  border: 1px solid var(--line-strong);
  border-radius: 18px;
  background: var(--surface-solid);
}
.donation-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
}
.donation-head span {
  font: 800 1rem var(--font-mono);
  color: var(--accent);
}
.donation-head small {
  color: var(--muted);
}
.donation-card > code {
  display: block;
  padding: 14px;
  margin-bottom: 12px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--bg);
  overflow-wrap: anywhere;
  color: var(--text);
  font: 600 0.78rem/1.6 var(--font-mono);
}
.donation-card p {
  margin: 13px 0 0;
  color: var(--muted-2);
  font-size: 0.72rem;
}
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--bg-elev);
}
.footer-inner {
  min-height: 180px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
}
.footer-inner strong {
  font-size: 1.05rem;
}
.footer-inner p {
  max-width: 520px;
  color: var(--muted);
  font-size: 0.8rem;
}
.footer-inner > div:nth-child(2) {
  display: flex;
  gap: 16px;
  color: var(--muted);
  font-size: 0.78rem;
}
.footer-inner small {
  grid-column: 1/-1;
  padding: 18px 0;
  border-top: 1px solid var(--line);
  color: var(--muted-2);
}
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition:
    opacity 0.65s ease,
    transform 0.65s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
}
/* Course page */
.course-hero {
  padding-block: 78px 64px;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}
.course-hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 34px;
  align-items: center;
}
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  color: var(--muted);
  font-size: 0.76rem;
  margin-bottom: 34px;
}
.breadcrumbs span:last-child {
  color: var(--text);
}
.availability-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 10px;
  border: 1px solid rgba(74, 222, 128, 0.25);
  border-radius: 999px;
  background: rgba(74, 222, 128, 0.07);
  color: var(--success);
  font-size: 0.72rem;
  font-weight: 750;
}
.availability-pill span {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 10px rgba(74, 222, 128, 0.6);
}
.course-hero h1 {
  margin: 14px 0 18px;
  font-size: clamp(3rem, 7vw, 6.8rem);
  line-height: 0.9;
  letter-spacing: -0.075em;
}
.course-hero-copy > p:not(.eyebrow) {
  max-width: 720px;
  color: var(--muted);
  font-size: 1.08rem;
}
.course-spec-card {
  position: relative;
  min-height: 470px;
  display: flex;
  flex-direction: column;
  justify-content: end;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 25px;
  overflow: hidden;
  background: linear-gradient(145deg, var(--surface), var(--surface-2));
  box-shadow: var(--shadow);
}
.course-scene {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.course-spec-card::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    transparent 38%,
    var(--surface-solid) 92%
  );
  pointer-events: none;
}
.spec-content {
  position: relative;
  z-index: 2;
}
.spec-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}
.spec-grid div {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: color-mix(in srgb, var(--surface-solid) 82%, transparent);
}
.spec-grid strong,
.spec-grid span {
  display: block;
}
.spec-grid strong {
  font-size: 1.05rem;
}
.spec-grid span {
  color: var(--muted);
  font-size: 0.7rem;
}
.spec-line {
  display: flex;
  justify-content: space-between;
  margin-top: 12px;
  padding: 13px 2px 0;
  color: var(--muted);
  font-size: 0.75rem;
}
.spec-line b {
  color: var(--success);
}
.course-overview-grid {
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  gap: 24px;
}
.overview-copy h2 {
  margin: 0;
  font-size: clamp(2rem, 4.2vw, 3.8rem);
  line-height: 1.05;
  letter-spacing: -0.05em;
}
.overview-copy > p:not(.eyebrow) {
  color: var(--muted);
  max-width: 700px;
}
.outcome-card {
  padding: 27px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
}
.outcome-card h3 {
  margin: 0 0 15px;
}
.outcome-card ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}
.outcome-card li {
  display: flex;
  gap: 9px;
  color: var(--muted);
  font-size: 0.88rem;
}
.outcome-card li::before {
  content: "✓";
  color: var(--accent);
  font-weight: 800;
}
.section-heading.split {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 28px;
}
.section-heading.split > p {
  max-width: 560px;
  margin: 0;
}
.chapter-list {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}
.chapter-card {
  border: 1px solid var(--line);
  border-radius: 17px;
  background: var(--surface);
  overflow: hidden;
}
.chapter-card summary {
  display: grid;
  grid-template-columns: 52px 1fr auto 28px;
  gap: 14px;
  align-items: center;
  padding: 18px;
  cursor: pointer;
  list-style: none;
}
.chapter-card summary::-webkit-details-marker {
  display: none;
}
.chapter-number {
  width: 43px;
  height: 43px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 11px;
  color: var(--accent);
  font: 700 0.76rem var(--font-mono);
  background: var(--surface-2);
}
.chapter-card summary p {
  margin: 0;
  color: var(--muted);
  font-size: 0.67rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
}
.chapter-card summary h3 {
  margin: 2px 0 0;
  font-size: 1rem;
}
.lesson-count {
  color: var(--muted);
  font-size: 0.72rem;
}
.summary-chevron {
  transition: 0.2s;
}
.chapter-card[open] .summary-chevron {
  transform: rotate(90deg);
}
.lesson-list {
  border-top: 1px solid var(--line);
}
.lesson-row {
  min-height: 58px;
  display: grid;
  grid-template-columns: 40px 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 10px 18px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
}
.lesson-row:last-child {
  border-bottom: 0;
}
.lesson-row > span {
  font: 650 0.68rem var(--font-mono);
}
.lesson-row strong,
.lesson-row small {
  display: block;
}
.lesson-row strong {
  color: var(--text);
  font-size: 0.82rem;
  font-weight: 620;
}
.lesson-row small {
  margin-top: 2px;
  color: var(--muted-2);
  font-size: 0.66rem;
}
.lesson-row > b {
  font-size: 0.7rem;
}
.lesson-row.live {
  background: rgba(74, 222, 128, 0.035);
}
.lesson-row.live > b {
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--accent);
}
.lesson-row.live:hover {
  background: var(--accent-soft);
}
/* Lesson */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1000;
  height: 2px;
  width: 0;
  background: linear-gradient(
    90deg,
    var(--accent),
    var(--accent-2),
    var(--accent-3)
  );
  box-shadow: 0 0 10px var(--accent);
}
.lesson-shell {
  display: grid;
  grid-template-columns: 290px minmax(0, 1fr);
  min-height: calc(100vh - var(--header-h));
}
.course-sidebar {
  position: sticky;
  top: var(--header-h);
  height: calc(100vh - var(--header-h));
  border-right: 1px solid var(--line);
  background: var(--bg-elev);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
.sidebar-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px;
  border-bottom: 1px solid var(--line);
}
.sidebar-head > a {
  display: flex;
  gap: 10px;
  align-items: center;
}
.sidebar-head small,
.sidebar-head strong {
  display: block;
}
.sidebar-head small {
  color: var(--muted);
  font-size: 0.62rem;
}
.sidebar-head strong {
  font-size: 0.78rem;
}
.sidebar-head button {
  display: none;
  border: 0;
  background: transparent;
  font-size: 1.5rem;
  cursor: pointer;
}
.sidebar-search {
  display: flex;
  gap: 8px;
  align-items: center;
  margin: 12px;
  padding: 9px 11px;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--muted);
}
.sidebar-search input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--text);
  font-size: 0.75rem;
}
.sidebar-curriculum {
  flex: 1;
  overflow: auto;
  padding: 0 9px 16px;
}
.sidebar-chapter {
  border-bottom: 1px solid var(--line);
}
.sidebar-chapter summary {
  display: grid;
  grid-template-columns: 27px 1fr;
  gap: 7px;
  padding: 11px 5px;
  cursor: pointer;
  list-style: none;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
}
.sidebar-chapter summary::-webkit-details-marker {
  display: none;
}
.sidebar-chapter summary > span {
  font: 700 0.64rem var(--font-mono);
  color: var(--accent);
}
.sidebar-chapter > div {
  padding: 0 0 9px;
}
.sidebar-lesson {
  display: grid;
  grid-template-columns: 25px 1fr auto;
  gap: 6px;
  align-items: start;
  padding: 7px 6px;
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.68rem;
  line-height: 1.4;
}
.sidebar-lesson > span {
  font: 600 0.6rem var(--font-mono);
}
.sidebar-lesson i {
  font-style: normal;
  color: var(--muted-2);
  font-size: 0.55rem;
}
.sidebar-lesson.is-current {
  background: var(--accent-soft);
  color: var(--text);
}
.sidebar-lesson.is-planned {
  opacity: 0.72;
}
.sidebar-lesson[data-hidden="true"],
.sidebar-lesson[hidden],
.sidebar-chapter[hidden] {
  display: none;
}
.sidebar-empty {
  margin: 10px 5px 14px;
  padding: 13px;
  border: 1px dashed var(--line-strong);
  border-radius: 10px;
  color: var(--muted);
  background: var(--surface-2);
  font-size: 0.7rem;
  text-align: center;
}
.lesson-main {
  min-width: 0;
}
.lesson-mobile-bar {
  display: none;
  position: sticky;
  top: var(--header-h);
  z-index: 40;
  padding: 10px 16px;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(18px);
}
.lesson-mobile-bar button {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  cursor: pointer;
}
.lesson-container {
  width: min(calc(100% - 48px), 860px);
  margin: auto;
  padding: 64px 0 110px;
}
.lesson-breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--muted);
  font-size: 0.72rem;
}
.lesson-header {
  padding: 32px 0 38px;
  border-bottom: 1px solid var(--line);
}
.lesson-header h1 {
  margin: 14px 0 18px;
  font-size: clamp(2.6rem, 6vw, 5.4rem);
  line-height: 0.95;
  letter-spacing: -0.065em;
}
.lesson-header > p {
  max-width: 760px;
  color: var(--muted);
  font-size: 1.05rem;
}
.lesson-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-top: 22px;
}
.lesson-meta span {
  padding: 6px 9px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.68rem;
}
.lesson-toc {
  margin: 30px 0;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface);
}
.lesson-toc strong {
  display: block;
  margin-bottom: 11px;
}
.lesson-toc ol {
  margin: 0;
  padding-left: 20px;
  columns: 2;
  column-gap: 30px;
}
.lesson-toc li {
  margin: 6px 0;
  color: var(--muted);
  font-size: 0.78rem;
}
.lesson-toc a:hover {
  color: var(--accent);
}
.lesson-content {
  font-size: 1rem;
}
.lesson-content section {
  padding-top: 52px;
}
.lesson-content h2 {
  margin: 0 0 18px;
  font-size: clamp(1.8rem, 3.5vw, 2.7rem);
  line-height: 1.08;
  letter-spacing: -0.045em;
}
.lesson-content h3 {
  margin: 31px 0 11px;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
}
.lesson-content p {
  color: color-mix(in srgb, var(--text) 83%, var(--muted));
}
.lesson-content ul,
.lesson-content ol {
  color: color-mix(in srgb, var(--text) 83%, var(--muted));
  padding-left: 23px;
}
.lesson-content li {
  margin: 7px 0;
}
.lesson-content strong {
  color: var(--text);
}
.lesson-content a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 35%, transparent);
  text-underline-offset: 3px;
}
.lesson-content code:not(pre code) {
  padding: 0.14em 0.4em;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface-2);
  color: var(--accent);
  font: 600 0.86em var(--font-mono);
}
.objectives {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 9px;
  margin: 26px 0;
}
.objective {
  padding: 15px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}
.objective span {
  display: block;
  color: var(--accent);
  font: 700 0.66rem var(--font-mono);
}
.objective p {
  margin: 6px 0 0;
  font-size: 0.82rem;
}
.callout {
  margin: 24px 0;
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 12px;
  background: var(--surface);
}
.callout strong {
  display: block;
  margin-bottom: 5px;
}
.callout p {
  margin: 0;
  color: var(--muted);
}
.callout.warning {
  border-left-color: var(--warning);
}
.concept-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin: 24px 0;
}
.concept-card {
  padding: 19px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
}
.concept-card .concept-icon {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: var(--accent-soft);
  color: var(--accent);
}
.concept-card h3 {
  margin: 15px 0 7px;
  font-size: 1.04rem;
}
.concept-card p {
  margin: 0;
  font-size: 0.84rem;
  color: var(--muted);
}
.architecture-diagram {
  margin: 28px 0;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  overflow: auto;
}
.diagram-flow {
  min-width: 650px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
  gap: 30px;
}
.diagram-node {
  position: relative;
  padding: 17px;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  background: var(--surface-solid);
  text-align: center;
}
.diagram-node:not(:last-child)::after {
  content: "→";
  position: absolute;
  right: -23px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--accent);
  font: 700 1.1rem var(--font-mono);
}
.diagram-node strong,
.diagram-node small {
  display: block;
}
.diagram-node small {
  margin-top: 4px;
  color: var(--muted);
  font-size: 0.66rem;
}
.diagram-caption {
  margin: 14px 0 0;
  color: var(--muted-2);
  font-size: 0.7rem;
  text-align: center;
}
.code-window {
  margin: 24px 0;
  border: 1px solid var(--code-border);
  border-radius: 16px;
  background: var(--code-bg);
  overflow: hidden;
  box-shadow: var(--code-shadow);
  transition:
    background-color 0.25s,
    border-color 0.25s,
    box-shadow 0.25s;
}
.code-head {
  min-height: 47px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px 0 15px;
  border-bottom: 1px solid var(--code-border);
  background: linear-gradient(
    180deg,
    var(--code-head-start),
    var(--code-head-end)
  );
  color: var(--code-head-text);
  transition:
    background 0.25s,
    color 0.25s,
    border-color 0.25s;
}
.code-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font: 650 0.7rem var(--font-mono);
}
.code-dots {
  display: flex;
  gap: 6px;
}
.code-dots i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #64748b;
}
.code-dots i:first-child {
  background: #fb7185;
}
.code-dots i:nth-child(2) {
  background: #fbbf24;
}
.code-dots i:nth-child(3) {
  background: #4ade80;
}
.copy-code {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px;
  border: 1px solid var(--code-copy-border);
  border-radius: 7px;
  background: var(--code-copy-bg);
  color: var(--code-head-text);
  cursor: pointer;
  font-size: 0.65rem;
  transition: 0.2s;
}
.copy-code:hover {
  color: var(--code-copy-hover);
  border-color: var(--line-strong);
}
.code-window pre {
  margin: 0;
  padding: 20px;
  overflow: auto;
  background: var(--code-bg);
  transition: background-color 0.25s;
}
.code-window code {
  display: block;
  min-width: max-content;
  color: var(--code-text);
  font: 500 0.82rem/1.75 var(--font-mono);
  counter-reset: line;
}
.code-line {
  display: block;
  position: relative;
  padding-left: 42px;
}
.code-line::before {
  counter-increment: line;
  content: counter(line);
  position: absolute;
  left: 0;
  width: 25px;
  text-align: right;
  color: var(--code-line-number);
  user-select: none;
}
.data-table {
  width: 100%;
  margin: 24px 0;
  border-collapse: separate;
  border-spacing: 0;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  font-size: 0.82rem;
}
.data-table th,
.data-table td {
  padding: 12px 14px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  text-align: left;
}
.data-table th:last-child,
.data-table td:last-child {
  border-right: 0;
}
.data-table tr:last-child td {
  border-bottom: 0;
}
.data-table th {
  background: var(--surface-2);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
}
.data-table td {
  color: var(--muted);
}
.checkpoint {
  margin: 34px 0;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 17px;
  background: linear-gradient(145deg, var(--surface), var(--surface-2));
}
.checkpoint h3 {
  margin: 0 0 13px;
}
.checkpoint ol {
  margin-bottom: 0;
}
.answer-toggle {
  margin-top: 13px;
}
.answer-toggle summary {
  cursor: pointer;
  color: var(--accent);
  font-weight: 700;
}
.answer-toggle p {
  padding: 12px;
  margin: 9px 0 0;
  border-left: 2px solid var(--accent);
  background: var(--surface-solid);
}
.lesson-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 58px;
  padding-top: 25px;
  border-top: 1px solid var(--line);
}
.lesson-nav a,
.lesson-nav span {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 13px;
  background: var(--surface);
}
.lesson-nav small,
.lesson-nav strong {
  display: block;
}
.lesson-nav small {
  color: var(--muted);
  font-size: 0.65rem;
}
.lesson-nav strong {
  margin-top: 3px;
  font-size: 0.8rem;
}
.lesson-nav .next {
  text-align: right;
}
.lesson-nav .disabled {
  opacity: 0.45;
}
.lesson-support {
  width: min(calc(100% - 48px), 860px);
  margin: 0 auto 90px;
}
.lesson-support .support-grid {
  grid-template-columns: 1fr;
}
.lesson-support .donation-card {
  margin-top: 6px;
}
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 130;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(3px);
}
/* 404 */
.error-page {
  min-height: calc(100vh - var(--header-h));
  display: grid;
  place-items: center;
  text-align: center;
}
.error-card {
  max-width: 700px;
  padding: 46px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--surface);
  box-shadow: var(--shadow);
}
.error-code {
  font: 800 clamp(4rem, 14vw, 9rem)/1 var(--font-mono);
  color: transparent;
  background: linear-gradient(
    90deg,
    var(--accent),
    var(--accent-2),
    var(--accent-3)
  );
  -webkit-background-clip: text;
  background-clip: text;
}
.error-card h1 {
  margin: 12px 0;
}
.error-card p {
  color: var(--muted);
}
@media (max-width: 1050px) {
  .hero-layout,
  .course-hero-grid {
    grid-template-columns: 1fr;
  }
  .hero-visual {
    min-height: 500px;
  }
  .course-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .method-grid {
    grid-template-columns: 1fr 1fr;
  }
  .stage-row {
    grid-template-columns: 70px 230px 1fr 32px;
  }
  .lesson-shell {
    grid-template-columns: 1fr;
  }
  .course-sidebar {
    position: fixed;
    z-index: 140;
    top: 0;
    left: 0;
    height: 100vh;
    width: min(90vw, 330px);
    transform: translateX(-102%);
    transition: 0.25s;
    box-shadow: var(--shadow);
  }
  .course-sidebar.is-open {
    transform: none;
  }
  .sidebar-head button {
    display: block;
  }
  .sidebar-overlay.is-open {
    display: block;
  }
  .lesson-mobile-bar {
    display: block;
  }
  .course-overview-grid {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 780px) {
  :root {
    --header-h: 64px;
  }
  .section-shell {
    width: min(calc(100% - 28px), var(--content));
  }
  .desktop-nav,
  .desktop-only {
    display: none;
  }
  .mobile-menu-button {
    display: grid;
  }
  .brand-copy small {
    display: none;
  }
  .hero-layout {
    padding-block: 54px 68px;
  }
  .hero-copy h1 {
    font-size: clamp(3.2rem, 16vw, 5.2rem);
  }
  .hero-visual {
    min-height: 430px;
  }
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }
  .stat:nth-child(2) {
    border-right: 0;
  }
  .stat:nth-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }
  .intro-grid,
  .support-grid {
    grid-template-columns: 1fr;
  }
  .roadmap-head,
  .catalogue-head,
  .section-heading.split {
    display: block;
  }
  .roadmap-head > p,
  .catalogue-head > p,
  .section-heading.split > p {
    margin-top: 15px;
  }
  .stage-row {
    grid-template-columns: 56px 1fr 28px;
  }
  .stage-courses {
    grid-column: 2/-1;
  }
  .stage-title {
    grid-column: 2;
  }
  .stage-arrow {
    grid-column: 3;
    grid-row: 1;
  }
  .course-toolbar {
    grid-template-columns: 1fr 1fr;
    position: relative;
    top: auto;
  }
  .course-toolbar .search-box {
    grid-column: 1/-1;
  }
  .course-grid {
    grid-template-columns: 1fr;
  }
  .stage-heading p {
    display: none;
  }
  .method-grid {
    grid-template-columns: 1fr;
  }
  .footer-inner {
    grid-template-columns: 1fr;
    padding-top: 45px;
  }
  .footer-inner > div:nth-child(2) {
    flex-wrap: wrap;
  }
  .lesson-container {
    width: min(calc(100% - 30px), 860px);
    padding-top: 40px;
  }
  .lesson-toc ol {
    columns: 1;
  }
  .objectives,
  .concept-grid {
    grid-template-columns: 1fr;
  }
  .lesson-support {
    width: min(calc(100% - 30px), 860px);
  }
  .course-spec-card {
    min-height: 390px;
  }
  .course-hero {
    padding-top: 48px;
  }
}
@media (max-width: 500px) {
  .hero-visual {
    min-height: 390px;
  }
  .hero-query-card {
    left: 14px;
    right: 14px;
    bottom: 14px;
  }
  .hero-query-card pre {
    font-size: 0.67rem;
  }
  .course-toolbar {
    grid-template-columns: 1fr;
  }
  .course-toolbar .search-box {
    grid-column: auto;
  }
  .stats-grid {
    grid-template-columns: 1fr;
  }
  .stat {
    border-right: 0;
    border-bottom: 1px solid var(--line) !important;
  }
  .stat:last-child {
    border-bottom: 0 !important;
  }
  .support-grid {
    padding: 24px;
  }
  .lesson-nav {
    grid-template-columns: 1fr;
  }
  .lesson-nav .next {
    text-align: left;
  }
  .chapter-card summary {
    grid-template-columns: 45px 1fr 24px;
  }
  .lesson-count {
    display: none;
  }
  .lesson-row {
    grid-template-columns: 30px 1fr;
  }
  .lesson-row > b {
    grid-column: 2;
  }
  .course-hero h1 {
    font-size: 3.35rem;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Dedicated MathJax display blocks */
.math-display {
  margin: 1.45rem 0;
  padding: 0.35rem 0;
  overflow-x: auto;
  overflow-y: hidden;
  color: var(--text);
  text-align: center;
}
.math-display mjx-container {
  display: block !important;
  width: 100%;
  margin: 0.65rem 0 !important;
  color: var(--text) !important;
  font-size: 1.08rem !important;
  line-height: 1.4;
  text-align: center;
  overflow: visible;
}
.math-display mjx-container[jax="CHTML"] {
  min-width: max-content;
}
/* MathJax SVG output must never inherit the generic icon SVG rule above. */
mjx-container[jax="SVG"] > svg {
  width: auto !important;
  height: auto !important;
  min-width: 0 !important;
  max-width: none !important;
  display: inline-block !important;
  overflow: visible !important;
  fill: currentColor !important;
  stroke: none !important;
  stroke-width: 0 !important;
  stroke-linecap: initial !important;
  stroke-linejoin: initial !important;
  vertical-align: middle;
}
mjx-container[jax="SVG"] > svg path,
mjx-container[jax="SVG"] > svg use,
mjx-container[jax="SVG"] > svg g {
  fill: currentColor !important;
  stroke: none !important;
  stroke-width: 0 !important;
}

/* =========================================================
   Lesson global refinements
   ========================================================= */

/* Justify normal prose paragraphs inside lesson content */
.lesson-content > p,
.lesson-content section > p {
  text-align: justify;
  text-justify: inter-word;
}

/* Reduce lesson donation/support vertical spacing by ~50% */
.lesson-support {
  margin-bottom: 45px;
}

.lesson-support .support-section {
  padding-block: 48px;
}

/* Donation/support section must appear immediately.
   Disable the global scroll-reveal animation only here. */
.lesson-support .support-grid.reveal {
  opacity: 1;
  transform: none;
  transition: none;
}
/* Move only the lesson support card closer to Previous / Next buttons */
.lesson-page .lesson-support .support-grid {
  margin-top: -60px;
}