/* Learn / courses · elevated dark paper, calm hierarchy */
.learn-page {
  padding-bottom: 80px;
}

.learn-hero {
  padding: calc(var(--nav-h) + 56px) 0 40px;
}

.learn-hero .section-label {
  margin-bottom: 12px;
}

.learn-hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 300;
  text-transform: lowercase;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 16px;
}

.learn-hero .section-lede {
  max-width: 52ch;
  margin-bottom: 0;
}

.learn-ladder {
  display: grid;
  gap: 20px;
  margin-top: 8px;
}

@media (min-width: 720px) {
  .learn-ladder {
    grid-template-columns: 1fr 1fr;
  }
}

.course-card {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: clamp(28px, 4vw, 36px);
  background:
    radial-gradient(ellipse 70% 60% at 0% 0%, rgba(168, 85, 247, 0.1), transparent 55%),
    var(--bg-card);
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: border-color 0.25s, box-shadow 0.25s;
}

.course-card:hover {
  border-color: rgba(168, 85, 247, 0.4);
  box-shadow: 0 0 36px rgba(168, 85, 247, 0.1);
}

.course-card-coming {
  opacity: 0.78;
  background:
    radial-gradient(ellipse 50% 40% at 100% 100%, rgba(168, 85, 247, 0.05), transparent 50%),
    var(--bg-elevated);
}

.course-card-coming:hover {
  border-color: var(--line);
  box-shadow: none;
}

.course-level {
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--purple-bright);
  font-weight: 500;
}

.course-card h2,
.course-card h3 {
  font-size: 1.35rem;
  font-weight: 400;
  text-transform: lowercase;
  letter-spacing: -0.01em;
}

.course-card p {
  color: var(--text-muted);
  font-weight: 300;
  font-size: 0.95rem;
  flex: 1;
}

.course-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

.course-badge {
  display: inline-block;
  font-size: 0.65rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 4px 10px;
  width: fit-content;
}

.course-badge-live {
  color: var(--purple-bright);
  border-color: rgba(168, 85, 247, 0.4);
}

.learn-coming-row {
  margin-top: 36px;
  display: grid;
  gap: 16px;
}

@media (min-width: 720px) {
  .learn-coming-row {
    grid-template-columns: 1fr 1fr;
  }
}

.coming-card {
  border: 1px dashed rgba(255, 255, 255, 0.12);
  border-radius: 14px;
  padding: 24px 28px;
  background: rgba(255, 255, 255, 0.02);
}

.coming-card h3 {
  font-size: 1.05rem;
  font-weight: 400;
  text-transform: lowercase;
  margin-bottom: 8px;
}

.coming-card p {
  color: var(--text-muted);
  font-weight: 300;
  font-size: 0.9rem;
  margin: 0;
}

.learn-note {
  margin-top: 40px;
  padding: 20px 24px;
  border-left: 2px solid var(--purple);
  background: rgba(168, 85, 247, 0.05);
  color: var(--text-muted);
  font-weight: 300;
  font-size: 0.9rem;
  max-width: 60ch;
}

/* Lesson pages */
.lesson {
  padding: calc(var(--nav-h) + 48px) 0 96px;
}

.lesson-layout {
  display: grid;
  gap: 40px;
}

@media (min-width: 960px) {
  .lesson-layout {
    grid-template-columns: 200px 1fr;
    gap: 56px;
    align-items: start;
  }
}

.lesson-toc {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
}

.lesson-toc nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.lesson-toc p {
  font-size: 0.65rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--purple-bright);
  margin-bottom: 12px;
  font-weight: 500;
}

.lesson-toc a {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 300;
  transition: color 0.2s;
  line-height: 1.35;
}

.lesson-toc a:hover {
  color: var(--purple-bright);
}

.lesson-crumb {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 300;
  margin-bottom: 20px;
}

.lesson-crumb a {
  color: var(--purple-bright);
}

.lesson-crumb a:hover {
  color: #fff;
}

.lesson-header h1 {
  font-size: clamp(1.85rem, 4.5vw, 2.6rem);
  font-weight: 300;
  text-transform: lowercase;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 14px;
}

.lesson-header .lede {
  color: var(--text-muted);
  font-weight: 300;
  font-size: 1.05rem;
  max-width: 54ch;
  margin-bottom: 8px;
}

.lesson-body {
  max-width: 68ch;
}

.lesson-body section {
  padding: 36px 0 8px;
  border-top: 1px solid var(--line);
  margin-top: 8px;
}

.lesson-body section:first-of-type {
  border-top: none;
  padding-top: 24px;
}

.lesson-body h2 {
  font-size: 1.25rem;
  font-weight: 400;
  text-transform: lowercase;
  letter-spacing: -0.01em;
  margin-bottom: 14px;
  color: var(--text);
}

.lesson-body p {
  color: var(--text-muted);
  font-weight: 300;
  margin-bottom: 14px;
  font-size: 1rem;
  line-height: 1.7;
}

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

.lesson-body ul {
  list-style: disc;
  padding-left: 1.25rem;
  margin: 0 0 16px;
  color: var(--text-muted);
  font-weight: 300;
}

.lesson-body li {
  margin-bottom: 8px;
  line-height: 1.6;
}

.rule-of-thumb {
  margin: 22px 0;
  padding: 18px 20px 18px 22px;
  border-radius: 12px;
  border: 1px solid rgba(168, 85, 247, 0.28);
  background:
    linear-gradient(90deg, rgba(168, 85, 247, 0.12), transparent 40%),
    var(--bg-elevated);
}

.rule-of-thumb .rot-label {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--purple-bright);
  font-weight: 500;
  margin-bottom: 8px;
}

.rule-of-thumb p {
  margin: 0 !important;
  color: var(--text) !important;
  font-weight: 300;
  font-size: 0.95rem;
  line-height: 1.55;
}

.lesson-footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 48px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

@media (max-width: 959px) {
  .lesson-toc {
    position: static;
  }
  .lesson-toc nav {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 10px 18px;
  }
}

/* ── Diagrams & mood visuals (Drive-deck clarity) ── */
.lesson-mood {
  margin: 20px 0 28px;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: #050508;
  aspect-ratio: 21 / 9;
  max-height: 280px;
}

.lesson-mood img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  opacity: 0.92;
}

.lesson-mood-caption {
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: lowercase;
  color: var(--text-muted);
  margin: -20px 0 24px;
  padding: 0 4px;
  font-weight: 300;
}

.diagram {
  margin: 24px 0 28px;
  padding: 20px 18px 18px;
  border-radius: 14px;
  border: 1px solid rgba(168, 85, 247, 0.28);
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(168, 85, 247, 0.08), transparent 60%),
    #050508;
  overflow: hidden;
}

.diagram-title {
  font-size: 0.65rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--purple-bright);
  font-weight: 500;
  margin: 0 0 14px;
}

.diagram-note {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 300;
  margin: 12px 0 0;
  line-height: 1.45;
}

.diagram svg {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

/* Flow blocks (satellite value chain / stages style) */
.flow-row {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 8px;
  justify-content: flex-start;
}

.flow-box {
  flex: 1 1 100px;
  min-width: 88px;
  border: 1px solid rgba(168, 85, 247, 0.4);
  border-radius: 10px;
  padding: 12px 10px;
  background: rgba(168, 85, 247, 0.08);
  text-align: center;
}

.flow-box strong {
  display: block;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text);
  text-transform: lowercase;
  margin-bottom: 4px;
}

.flow-box span {
  display: block;
  font-size: 0.7rem;
  color: var(--text-muted);
  font-weight: 300;
  line-height: 1.35;
}

.flow-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--purple-bright);
  font-size: 1.1rem;
  flex: 0 0 auto;
  padding: 0 2px;
  align-self: center;
}

@media (max-width: 640px) {
  .flow-arrow {
    width: 100%;
    transform: rotate(90deg);
    padding: 2px 0;
  }
  .flow-box {
    flex: 1 1 100%;
  }
}

/* Compare cards LEO / GEO */
.compare-grid {
  display: grid;
  gap: 12px;
  margin: 18px 0 8px;
}

@media (min-width: 560px) {
  .compare-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.compare-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  background: var(--bg-elevated);
}

.compare-card h3 {
  font-size: 0.95rem;
  font-weight: 500;
  text-transform: lowercase;
  color: var(--purple-bright);
  margin: 0 0 10px;
}

.compare-card dl {
  margin: 0;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 6px 12px;
  font-size: 0.85rem;
}

.compare-card dt {
  color: var(--text-muted);
  font-weight: 300;
}

.compare-card dd {
  margin: 0;
  color: var(--text);
  font-weight: 400;
}

/* Orbit altitude bands */
.orbit-bands {
  margin: 18px 0;
  padding: 16px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #050508;
}

.orbit-band {
  display: grid;
  grid-template-columns: 72px 1fr auto;
  gap: 10px;
  align-items: center;
  margin-bottom: 10px;
}

.orbit-band:last-child {
  margin-bottom: 0;
}

.orbit-band .ob-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--purple-bright);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.orbit-band .ob-bar {
  height: 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  overflow: hidden;
  position: relative;
}

.orbit-band .ob-fill {
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--purple-dim), var(--purple-bright));
}

.orbit-band .ob-meta {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 300;
  white-space: nowrap;
}

@media (max-width: 480px) {
  .orbit-band {
    grid-template-columns: 56px 1fr;
  }
  .orbit-band .ob-meta {
    grid-column: 1 / -1;
    padding-left: 66px;
  }
}

/* SVG path pulse animation */
.pulse-dot {
  fill: #e9d5ff;
  filter: drop-shadow(0 0 4px #a855f7);
}

.path-line {
  fill: none;
  stroke: rgba(168, 85, 247, 0.45);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-dasharray: 4 6;
}

.path-line-solid {
  fill: none;
  stroke: rgba(168, 85, 247, 0.55);
  stroke-width: 2.5;
  stroke-linecap: round;
}

.node-box {
  fill: rgba(168, 85, 247, 0.12);
  stroke: rgba(168, 85, 247, 0.55);
  stroke-width: 1.25;
}

.node-label {
  fill: #f2f2f5;
  font-family: Roboto, system-ui, sans-serif;
  font-size: 11px;
  font-weight: 500;
  text-anchor: middle;
}

.node-sub {
  fill: #9a9aad;
  font-family: Roboto, system-ui, sans-serif;
  font-size: 9px;
  font-weight: 300;
  text-anchor: middle;
}

@keyframes pulse-travel {
  0% { offset-distance: 0%; opacity: 0.3; }
  8% { opacity: 1; }
  92% { opacity: 1; }
  100% { offset-distance: 100%; opacity: 0.3; }
}

.anim-pulse {
  offset-rotate: 0deg;
  animation: pulse-travel 4.5s linear infinite;
}

.anim-pulse-slow {
  offset-rotate: 0deg;
  animation: pulse-travel 6.5s linear infinite;
}

@keyframes dash-flow {
  to { stroke-dashoffset: -40; }
}

.path-flowing {
  animation: dash-flow 1.2s linear infinite;
}

@media (prefers-reduced-motion: reduce) {
  .anim-pulse,
  .anim-pulse-slow,
  .path-flowing {
    animation: none !important;
  }
  .anim-pulse,
  .anim-pulse-slow {
    opacity: 1;
  }
}

/* Widen lesson body slightly when diagrams present */
.lesson-body {
  max-width: min(68ch, 100%);
}

.lesson-body .diagram,
.lesson-body .compare-grid,
.lesson-body .orbit-bands,
.lesson-body .flow-row,
.lesson-body .lesson-mood {
  max-width: 100%;
}

@media (min-width: 960px) {
  .lesson-body:has(.diagram) {
    max-width: 720px;
  }
}


/* Deeper tier teasers per course track */
.tier-intro {
  font-size: 0.9rem;
  font-weight: 300;
  color: var(--text-muted);
  max-width: 42rem;
  margin: 0 0 20px;
  line-height: 1.55;
}
.learn-tracks {
  display: grid;
  gap: 20px;
}
@media (min-width: 800px) {
  .learn-tracks { grid-template-columns: 1fr 1fr; gap: 24px; }
}
.track-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.track-title {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: lowercase;
  color: var(--purple-bright);
  margin: 0 0 4px;
}
.track-col .coming-card h4 {
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--text);
  margin-bottom: 8px;
}
.track-col .coming-card p {
  font-size: 0.88rem;
  font-weight: 300;
  color: var(--text-muted);
  line-height: 1.55;
}

.course-tiers {
  list-style: none;
  margin: 8px 0 0;
  padding: 14px 0 0;
  border-top: 1px dashed rgba(255, 255, 255, 0.1);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.course-tiers li {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 300;
  line-height: 1.4;
}

.course-tiers li span {
  display: inline-block;
  min-width: 2.2em;
  margin-right: 8px;
  color: var(--purple-bright);
  font-weight: 500;
  letter-spacing: 0.04em;
  font-size: 0.72rem;
  text-transform: uppercase;
}


.notice-grid {
  display: grid;
  gap: 12px;
  margin: 18px 0 16px;
}
@media (min-width: 560px) {
  .notice-grid { grid-template-columns: 1fr 1fr; }
}
.notice-card {
  border: 1px solid rgba(168, 85, 247, 0.28);
  border-radius: 12px;
  padding: 14px 16px;
  background: rgba(168, 85, 247, 0.06);
}
.notice-card h3 {
  font-size: 0.85rem;
  font-weight: 500;
  text-transform: lowercase;
  color: var(--purple-bright);
  margin: 0 0 6px;
  letter-spacing: 0.04em;
}
.notice-card p {
  margin: 0 !important;
  font-size: 0.88rem !important;
  line-height: 1.45;
}


.measure-grid {
  display: grid;
  gap: 14px;
  margin: 22px 0 8px;
}
@media (min-width: 720px) {
  .measure-grid { grid-template-columns: 1fr 1fr; }
}
.measure-card {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px 20px;
  background: rgba(255,255,255,0.02);
}
.measure-card h3 {
  font-size: 0.95rem;
  font-weight: 500;
  text-transform: lowercase;
  color: var(--purple-bright);
  margin-bottom: 6px;
}
.measure-feel {
  font-size: 0.85rem;
  color: var(--text);
  font-weight: 400;
  margin-bottom: 8px !important;
}
.measure-card p {
  font-size: 0.86rem;
  font-weight: 300;
  color: var(--text-muted);
  line-height: 1.5;
  margin: 0;
}
.measure-card strong { color: var(--text); font-weight: 500; }
.data-table-wrap { overflow-x: auto; margin-top: 4px; }
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8rem;
  font-weight: 300;
}
.data-table th, .data-table td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.data-table th {
  color: var(--purple-bright);
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: lowercase;
  font-size: 0.72rem;
}
.data-table td { color: var(--text-muted); }
.data-table td:first-child { color: var(--text); font-weight: 400; }


.subhead {
  font-size: 1.05rem;
  font-weight: 400;
  text-transform: lowercase;
  letter-spacing: -0.01em;
  margin: 28px 0 12px;
  color: var(--text);
}
.sine-path {
  stroke: #c084fc;
  stroke-width: 2.25;
  stroke-linecap: round;
  fill: none;
}
.sine-lo {
  stroke-dasharray: 8 6;
  animation: sine-flow 3.5s linear infinite;
}
.sine-hi {
  stroke: #e9d5ff;
  stroke-dasharray: 4 4;
  animation: sine-flow 1.6s linear infinite;
}
@keyframes sine-flow {
  to { stroke-dashoffset: -48; }
}
@media (prefers-reduced-motion: reduce) {
  .sine-lo, .sine-hi { animation: none; }
  .wave-bead { display: none; }
}
.wave-panel { margin-top: 4px; }


.metric-block {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px 24px;
  margin: 18px 0;
  background: rgba(255,255,255,0.02);
}
.metric-block h3 {
  font-size: 1.05rem;
  font-weight: 500;
  text-transform: lowercase;
  color: var(--purple-bright);
  margin-bottom: 10px;
}
.metric-block > p { margin-bottom: 10px; }
.metric-block .eq {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9rem;
  color: var(--text);
  background: rgba(168,85,247,0.08);
  border-left: 2px solid var(--purple);
  padding: 10px 14px;
  margin: 12px 0;
}
.metric-ranges {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.metric-ranges li {
  font-size: 0.9rem;
  font-weight: 300;
  color: var(--text-muted);
  line-height: 1.45;
  padding-left: 0;
}
.metric-ranges strong {
  color: var(--text);
  font-weight: 500;
}


.metric-ask {
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--text);
  margin: 0 0 10px;
}
.diagram-tall svg { min-height: 280px; }
.isl-label {
  fill: #e9d5ff;
  font-size: 11px;
  font-family: Roboto, system-ui, sans-serif;
  text-anchor: middle;
  letter-spacing: 0.04em;
}
.path-line-dashed { fill: none; }
.photo-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin: 20px 0 24px;
}
.photo-card {
  margin: 0;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: rgba(0,0,0,0.35);
}
.photo-card img {
  display: block;
  width: 100%;
  height: 180px;
  object-fit: cover;
}
.photo-card figcaption {
  font-size: 0.72rem;
  font-weight: 300;
  color: var(--text-muted);
  padding: 8px 12px 10px;
  letter-spacing: 0.01em;
}
@media (max-width: 640px) {
  .photo-row { grid-template-columns: 1fr; }
  .photo-card img { height: 200px; }
}


.wave-svg { overflow: visible; }
.bit-marks circle { opacity: 0.85; }


.eq-mini {
  fill: rgba(242,242,245,0.45);
  font-size: 10px;
  font-family: Roboto, system-ui, sans-serif;
  font-weight: 300;
  letter-spacing: 0.02em;
}
.sine-path {
  stroke: #a855f7;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: 0.9;
}
.sine-path.sine-hi {
  stroke: #c084fc;
  stroke-width: 1.5;
}


.peer-box {
  fill: rgba(168,85,247,0.06) !important;
  stroke: rgba(192,132,252,0.45) !important;
}
.diagram-tall svg text.node-label {
  text-anchor: inherit;
}


.sat-3d {
  background:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(168,85,247,0.12), transparent 55%),
    rgba(255,255,255,0.02);
}
.sat-3d svg {
  min-height: 300px;
}


.link-label {
  fill: #e9d5ff;
  font-size: 10px;
  font-family: Roboto, system-ui, sans-serif;
  font-weight: 400;
  letter-spacing: 0.03em;
  opacity: 0.9;
}