:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --surface-soft: #eef3f7;
  --line: #d8e0e7;
  --line-strong: #a9b7c3;
  --text: #17202a;
  --muted: #617080;
  --known: #15815b;
  --known-soft: #e1f4ec;
  --learning: #b26a16;
  --learning-soft: #fff0d8;
  --unknown: #7d8792;
  --unknown-soft: #edf0f2;
  --goal: #265db7;
  --goal-soft: #e4edff;
  --proposal: #7b3fb2;
  --proposal-soft: #f0e8f8;
  --danger: #b33a3a;
  --shadow: 0 16px 50px rgba(26, 38, 52, 0.11);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    linear-gradient(180deg, rgba(247, 248, 251, 0.96), rgba(247, 248, 251, 0.96)),
    repeating-linear-gradient(90deg, rgba(38, 93, 183, 0.06) 0 1px, transparent 1px 120px),
    repeating-linear-gradient(0deg, rgba(21, 129, 91, 0.05) 0 1px, transparent 1px 120px);
}

html[data-page="app"] #homeView,
html[data-page="course"] #homeView,
html[data-page="home"] #appShell {
  display: none !important;
}

html[data-route="course-detail"] .app-shell {
  grid-template-columns: minmax(0, 1fr);
}

html[data-route="course-detail"] .sidebar {
  display: none;
}

button,
input,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

.home-view {
  position: relative;
  min-height: 100vh;
  overflow: hidden;
  background: #f8faf8;
}

.home-graph-scene {
  position: absolute;
  inset: 0 0 auto 0;
  height: min(920px, 92vh);
  overflow: hidden;
  background: #f5faf8;
}

.home-graph-scene::before {
  position: absolute;
  inset: 0 auto 0 0;
  z-index: 1;
  width: min(900px, 54vw);
  content: "";
  background: rgba(248, 250, 248, 0.98);
  box-shadow: 104px 0 96px rgba(248, 250, 248, 0.82);
  pointer-events: none;
}

.home-graph-scene::after {
  position: absolute;
  inset: 0;
  z-index: 2;
  content: "";
  background:
    repeating-linear-gradient(90deg, rgba(23, 32, 42, 0.05) 0 1px, transparent 1px 88px),
    repeating-linear-gradient(0deg, rgba(23, 32, 42, 0.04) 0 1px, transparent 1px 88px);
  pointer-events: none;
}

.home-graph-edges,
.home-graph-nodes {
  position: absolute;
  z-index: 0;
  top: 0;
  left: 50%;
  width: 1720px;
  height: 920px;
  transform: translateX(-12%) scale(var(--home-graph-scale, 1));
  transform-origin: 0 0;
}

.home-graph-edges {
  opacity: 0.58;
}

.home-graph-edges path {
  fill: none;
  stroke: rgba(65, 81, 98, 0.46);
  stroke-width: 1.25;
}

.home-graph-edges path.cross {
  opacity: 0.34;
  stroke-width: 0.95;
}

.home-graph-edges path.foundations {
  stroke: rgba(0, 128, 148, 0.8);
}

.home-graph-edges path.algebra {
  stroke: rgba(38, 93, 183, 0.82);
}

.home-graph-edges path.analysis {
  stroke: rgba(21, 129, 91, 0.78);
}

.home-graph-edges path.geometry {
  stroke: rgba(214, 84, 47, 0.82);
}

.home-graph-edges path.topology {
  stroke: rgba(219, 91, 131, 0.82);
}

.home-graph-edges path.number {
  stroke: rgba(146, 95, 22, 0.84);
}

.home-graph-edges path.discrete {
  stroke: rgba(123, 63, 178, 0.8);
}

.home-graph-lane {
  position: absolute;
  padding: 4px 8px;
  border: 1px solid rgba(23, 32, 42, 0.08);
  border-radius: 999px;
  color: #17202a;
  background: rgba(255, 255, 255, 0.76);
  font-size: 0.66rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  transform: translate(-50%, -50%);
  box-shadow: 0 7px 18px rgba(26, 38, 52, 0.06);
}

.home-graph-lane.algebra {
  color: #214f9a;
}

.home-graph-lane.number {
  color: #8a5c16;
}

.home-graph-lane.foundations {
  color: #087081;
}

.home-graph-lane.topology {
  color: #b2456a;
}

.home-graph-lane.geometry {
  color: #b74d2c;
}

.home-graph-lane.analysis {
  color: #12704f;
}

.home-graph-lane.discrete {
  color: #6d3ca1;
}

.home-graph-node {
  position: absolute;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
  max-width: none;
  padding: 6px 9px;
  border: 1px solid rgba(23, 32, 42, 0.16);
  border-radius: 8px;
  color: #17202a;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 10px 30px rgba(26, 38, 52, 0.08);
  font-size: 0.68rem;
  font-weight: 820;
  line-height: 1.15;
  overflow: hidden;
  white-space: normal;
  transform: translate(-50%, -50%);
}

.home-graph-node small {
  display: block;
  margin-top: 2px;
  color: #617080;
  font-size: 0.58rem;
  font-weight: 760;
}

.home-graph-node.algebra {
  border-color: rgba(38, 93, 183, 0.36);
  background: rgba(220, 232, 255, 0.92);
}

.home-graph-node.analysis {
  border-color: rgba(21, 129, 91, 0.38);
  background: rgba(213, 243, 230, 0.92);
}

.home-graph-node.geometry {
  border-color: rgba(214, 84, 47, 0.42);
  background: rgba(255, 224, 211, 0.93);
}

.home-graph-node.topology {
  border-color: rgba(219, 91, 131, 0.42);
  background: rgba(255, 223, 235, 0.93);
}

.home-graph-node.number {
  border-color: rgba(146, 95, 22, 0.42);
  background: rgba(255, 238, 204, 0.94);
}

.home-graph-node.discrete {
  border-color: rgba(123, 63, 178, 0.36);
  background: rgba(234, 221, 247, 0.93);
}

.home-graph-node.foundations {
  border-color: rgba(0, 128, 148, 0.38);
  background: rgba(215, 243, 247, 0.92);
}

.home-nav {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 22px clamp(18px, 4vw, 54px);
}

.home-brand {
  margin: 0;
}

.site-nav,
.app-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.site-nav-link,
.app-nav-link {
  min-height: 38px;
  padding: 9px 12px;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--text);
  font-size: 0.86rem;
  font-weight: 820;
  text-decoration: none;
}

.site-nav-link:hover,
.app-nav-link:hover {
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.78);
}

.home-site-nav {
  position: relative;
  z-index: 3;
  justify-content: flex-end;
}

.home-enter-small {
  background: rgba(255, 255, 255, 0.72);
}

.home-hero {
  position: relative;
  z-index: 2;
  display: grid;
  align-items: center;
  min-height: min(680px, calc(100vh - 190px));
  padding: 40px clamp(18px, 6vw, 84px) 74px;
}

.home-copy {
  max-width: 760px;
}

.home-copy h2,
.home-copy > p,
.home-goal-form label {
  text-shadow:
    0 1px 0 rgba(248, 250, 248, 0.96),
    0 0 22px rgba(248, 250, 248, 0.96);
}

.home-copy h2 {
  max-width: 720px;
  margin: 0;
  font-size: clamp(2.4rem, 6.2vw, 5.8rem);
  line-height: 0.98;
  letter-spacing: 0;
}

.home-copy > p:not(.eyebrow) {
  max-width: 640px;
  margin: 22px 0 0;
  color: #334456;
  font-size: clamp(1rem, 1.4vw, 1.22rem);
  line-height: 1.6;
}

.home-goal-form {
  display: grid;
  gap: 9px;
  max-width: 660px;
  margin-top: 30px;
}

.home-goal-form label,
.home-course-preview label {
  color: #263340;
  font-size: 0.74rem;
  font-weight: 840;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.home-goal-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
  padding: 8px;
  border: 1px solid rgba(23, 32, 42, 0.15);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.78);
  box-shadow: var(--shadow);
}

.home-goal-row input {
  min-width: 0;
  min-height: 44px;
  padding: 0 12px;
  border: 0;
  border-radius: 6px;
  color: var(--text);
  background: transparent;
  font-weight: 760;
}

.home-goal-row input:focus {
  outline: 2px solid rgba(38, 93, 183, 0.25);
}

.home-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}

.home-actions .secondary-button {
  background: rgba(255, 255, 255, 0.7);
}

.home-lower {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 460px);
  gap: clamp(18px, 4vw, 44px);
  align-items: start;
  padding: 0 clamp(18px, 6vw, 84px) 54px;
}

.home-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.home-principles article,
.home-course-preview {
  padding: 16px;
  border: 1px solid rgba(23, 32, 42, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.86);
}

.home-principles span {
  color: var(--goal);
  font-size: 0.72rem;
  font-weight: 860;
}

.home-principles h3,
.home-course-preview h3 {
  margin: 7px 0 8px;
  font-size: 1rem;
}

.home-principles p,
.home-course-preview p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.52;
}

.home-course-preview {
  display: grid;
  gap: 10px;
}

.home-course-preview .eyebrow {
  margin: 0;
}

.home-formula {
  overflow-x: auto;
  padding: 10px;
  border: 1px solid rgba(38, 93, 183, 0.14);
  border-radius: 8px;
  background: #ffffff;
}

.home-course-preview textarea {
  min-height: 94px;
  resize: none;
}

.app-shell {
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  min-height: 100vh;
}

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 22px;
  border-right: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(18px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 4px;
}

.brand-mark {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid #143d5f;
  border-radius: 8px;
  color: #ffffff;
  background: #143d5f;
  font-weight: 800;
  letter-spacing: 0;
}

.brand h1,
.brand p,
.topbar h2,
.topbar p,
.panel h2,
.graph-head p {
  margin: 0;
}

.brand h1 {
  font-size: 1.05rem;
  line-height: 1.1;
}

.brand p,
.eyebrow,
.graph-head p {
  color: var(--muted);
  font-size: 0.78rem;
}

.app-nav {
  align-items: stretch;
  flex-direction: column;
  gap: 6px;
}

.app-nav-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  min-height: 40px;
  border-color: var(--line);
  color: var(--muted);
  background: rgba(255, 255, 255, 0.56);
}

.app-nav-link b {
  color: var(--text);
  font-size: 0.8rem;
}

body[data-page="app"] .app-nav-link[data-nav-page="app"],
body[data-page="course"] .app-nav-link[data-nav-page="course"] {
  border-color: rgba(38, 93, 183, 0.32);
  color: var(--goal);
  background: var(--goal-soft);
}

.workspace {
  min-width: 0;
  padding: 22px;
}

.topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 16px;
}

.eyebrow {
  margin-bottom: 4px;
  text-transform: uppercase;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.topbar h2 {
  font-size: 1.55rem;
  line-height: 1.15;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
  color: var(--muted);
  font-size: 0.78rem;
}

.legend span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 28px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.76);
}

.legend-dot {
  width: 9px;
  height: 9px;
  border-radius: 99px;
}

.legend-dot.known {
  background: var(--known);
}

.legend-dot.learning {
  background: var(--learning);
}

.legend-dot.unknown {
  background: var(--unknown);
}

.legend-dot.goal {
  background: var(--goal);
}

.main-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 16px;
  align-items: start;
}

.right-rail {
  position: sticky;
  top: 18px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-height: calc(100vh - 44px);
  overflow: auto;
}

.is-hidden {
  display: none !important;
}

.panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: var(--shadow);
}

.profile-panel,
.goal-panel,
.proposal-panel,
.study-panel,
.node-panel {
  padding: 16px;
}

.graph-panel {
  min-width: 0;
  overflow: hidden;
}

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.section-head h2 {
  font-size: 0.92rem;
}

.graph-head {
  padding: 16px 16px 0;
}

.icon-button,
.secondary-button,
.primary-button,
.quick-goals button,
.status-choice {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 36px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #ffffff;
  color: var(--text);
  font-weight: 750;
}

.icon-button {
  width: 34px;
  min-height: 34px;
  padding: 0;
}

.primary-button {
  border-color: #194d78;
  background: #194d78;
  color: #ffffff;
  padding: 0 14px;
}

.primary-button:disabled,
.secondary-button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

.secondary-button {
  padding: 0 13px;
}

.primary-button:hover:not(:disabled),
.secondary-button:hover:not(:disabled),
.icon-button:hover,
.quick-goals button:hover,
.status-choice:hover {
  transform: translateY(-1px);
}

.profile-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin: 0 0 16px;
}

.profile-stats div {
  min-width: 0;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.profile-stats dt {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.profile-stats dd {
  margin: 2px 0 0;
  font-size: 1.25rem;
  font-weight: 850;
}

.status-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.mini-pill,
.status-pill,
.proposal-badge {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  border-radius: 999px;
  border: 1px solid var(--line);
  padding: 0 9px;
  font-size: 0.72rem;
  font-weight: 780;
  color: var(--muted);
  background: #ffffff;
}

.status-pill.known,
.mini-pill.known {
  border-color: rgba(21, 129, 91, 0.25);
  color: var(--known);
  background: var(--known-soft);
}

.status-pill.learning,
.mini-pill.learning {
  border-color: rgba(178, 106, 22, 0.25);
  color: var(--learning);
  background: var(--learning-soft);
}

.status-pill.unknown,
.mini-pill.unknown {
  color: var(--unknown);
  background: var(--unknown-soft);
}

.status-pill.goal,
.mini-pill.goal {
  border-color: rgba(38, 93, 183, 0.25);
  color: var(--goal);
  background: var(--goal-soft);
}

.proposal-badge {
  color: var(--proposal);
  background: var(--proposal-soft);
}

.goal-form {
  display: grid;
  gap: 8px;
}

.input-label {
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 780;
}

.input-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px;
}

input {
  width: 100%;
  min-height: 40px;
  padding: 0 12px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: var(--text);
  background: #ffffff;
  outline: none;
}

input:focus {
  border-color: #194d78;
  box-shadow: 0 0 0 3px rgba(25, 77, 120, 0.12);
}

textarea {
  width: 100%;
  min-height: 96px;
  resize: vertical;
  padding: 10px 12px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: var(--text);
  background: #ffffff;
  line-height: 1.45;
  outline: none;
}

textarea:focus {
  border-color: #194d78;
  box-shadow: 0 0 0 3px rgba(25, 77, 120, 0.12);
}

.quick-goals {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.quick-goals button {
  min-height: 30px;
  padding: 0 10px;
  color: var(--muted);
  font-size: 0.75rem;
}

.graph-scroll {
  width: 100%;
  overflow: auto;
}

.graph-canvas {
  position: relative;
  width: 1160px;
  height: 640px;
  background:
    linear-gradient(90deg, rgba(216, 224, 231, 0.36) 1px, transparent 1px),
    linear-gradient(rgba(216, 224, 231, 0.36) 1px, transparent 1px);
  background-size: 80px 80px;
}

.edge-layer {
  position: absolute;
  inset: 0;
  width: 1160px;
  height: 640px;
  overflow: visible;
}

.edge-layer path {
  fill: none;
  stroke: #9eb0be;
  stroke-width: 2;
  marker-end: url("#arrow");
}

.edge-layer path.preview {
  stroke: rgba(123, 63, 178, 0.55);
  stroke-dasharray: 8 8;
}

.edge-layer path.active {
  stroke: #265db7;
  stroke-width: 3;
}

.edge-layer marker path {
  fill: #9eb0be;
}

.node-layer {
  position: absolute;
  inset: 0;
}

.graph-node {
  position: absolute;
  display: grid;
  align-content: center;
  width: 150px;
  min-height: 58px;
  padding: 9px 10px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: var(--text);
  background: #ffffff;
  box-shadow: 0 10px 24px rgba(26, 38, 52, 0.1);
  text-align: left;
  transition:
    transform 120ms ease,
    border-color 120ms ease,
    box-shadow 120ms ease;
}

.graph-node:hover,
.graph-node.selected {
  transform: translateY(-2px);
  box-shadow: 0 16px 34px rgba(26, 38, 52, 0.16);
}

.graph-node.selected {
  border-color: #17202a;
  outline: 3px solid rgba(23, 32, 42, 0.12);
}

.graph-node strong {
  display: block;
  overflow-wrap: anywhere;
  font-size: 0.82rem;
  line-height: 1.14;
}

.graph-node small {
  margin-top: 4px;
  overflow-wrap: anywhere;
  color: var(--muted);
  font-size: 0.68rem;
  line-height: 1.15;
}

.graph-node.known {
  border-color: rgba(21, 129, 91, 0.35);
  background: var(--known-soft);
}

.graph-node.learning {
  border-color: rgba(178, 106, 22, 0.35);
  background: var(--learning-soft);
}

.graph-node.unknown {
  opacity: 0.72;
  color: #49515a;
  background: var(--unknown-soft);
}

.graph-node.goal {
  border-color: rgba(38, 93, 183, 0.55);
  background: var(--goal-soft);
  box-shadow: 0 14px 32px rgba(38, 93, 183, 0.16);
}

.graph-node.proposed {
  border-color: rgba(123, 63, 178, 0.36);
  background: var(--proposal-soft);
}

.proposal-content {
  display: grid;
  gap: 14px;
}

.study-content {
  display: grid;
  gap: 12px;
}

.proposal-empty {
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.5;
}

.metric-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.metric {
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.metric b {
  display: block;
  font-size: 1.15rem;
}

.metric span {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.proposal-list,
.route-list,
.subtopic-list,
.evidence-list,
.study-list,
.review-list,
.assumption-list {
  display: grid;
  gap: 7px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.proposal-list li,
.route-list li,
.subtopic-list li,
.evidence-list li,
.study-list li,
.review-list li,
.assumption-list li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  color: var(--text);
  font-size: 0.84rem;
  line-height: 1.35;
}

.proposal-list li::before,
.route-list li::before,
.subtopic-list li::before,
.evidence-list li::before,
.study-list li::before,
.review-list li::before,
.assumption-list li::before {
  content: "";
  flex: 0 0 auto;
  width: 7px;
  height: 7px;
  margin-top: 6px;
  border-radius: 50%;
  background: var(--proposal);
}

.route-list li::before {
  background: var(--goal);
}

.subtopic-list li::before {
  background: var(--known);
}

.evidence-list li::before {
  background: var(--learning);
}

.study-list li::before {
  background: #194d78;
}

.review-list li::before {
  background: #263340;
}

.assumption-list li::before {
  background: var(--unknown);
}

.confidence-card,
.rationale-box {
  display: grid;
  gap: 8px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.confidence-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.confidence-head span,
.confidence-card p {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 760;
}

.confidence-head b {
  font-size: 0.9rem;
}

.confidence-card p,
.rationale-box p {
  margin: 0;
  line-height: 1.45;
}

.confidence-bar {
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: #dce3ea;
}

.confidence-bar span {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: #194d78;
}

.rationale-box {
  background: #f6f8fb;
}

.rationale-box p {
  color: var(--muted);
  font-size: 0.84rem;
}

.answer-pill {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 0 8px;
  border-radius: 999px;
  color: var(--goal);
  background: var(--goal-soft);
  font-size: 0.68rem;
  font-weight: 800;
}

.answer-pill.muted {
  color: var(--unknown);
  background: var(--unknown-soft);
}

.diagnostic-summary {
  display: grid;
  gap: 4px;
  padding: 10px;
  border: 1px solid rgba(21, 129, 91, 0.22);
  border-radius: 8px;
  background: var(--known-soft);
}

.diagnostic-summary b {
  color: var(--known);
  font-size: 0.84rem;
}

.diagnostic-summary p {
  margin: 0;
  color: #315f4d;
  font-size: 0.8rem;
  line-height: 1.4;
}

.study-section {
  display: grid;
  gap: 8px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.study-section h4 {
  margin: 0;
  color: #263340;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.study-section p {
  margin: 0;
  color: var(--text);
  font-size: 0.84rem;
  line-height: 1.48;
}

.proof-task {
  border-color: rgba(178, 106, 22, 0.24);
  background: var(--learning-soft);
}

.study-workbench {
  display: grid;
  gap: 10px;
  padding: 10px;
  border: 1px solid rgba(38, 93, 183, 0.22);
  border-radius: 8px;
  background: var(--goal-soft);
}

.study-field {
  display: grid;
  gap: 6px;
}

.study-field label {
  color: #263340;
  font-size: 0.76rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.study-saved {
  padding: 9px 10px;
  border: 1px solid rgba(38, 93, 183, 0.2);
  border-radius: 8px;
  color: var(--goal);
  background: var(--goal-soft);
  font-size: 0.82rem;
  font-weight: 760;
  line-height: 1.4;
}

.study-field textarea {
  min-height: 108px;
}

.latex-workbench {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(240px, 0.95fr);
  gap: 12px;
  align-items: stretch;
}

.latex-editor {
  display: grid;
  gap: 6px;
}

.latex-preview {
  display: grid;
  grid-template-rows: auto 1fr;
  min-height: 100%;
  border: 1px solid rgba(21, 129, 91, 0.18);
  border-radius: 8px;
  background: #fbfffd;
  overflow: hidden;
}

.latex-preview-head {
  padding: 8px 10px;
  border-bottom: 1px solid rgba(21, 129, 91, 0.14);
  color: #12704f;
  font-size: 0.68rem;
  font-weight: 860;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.latex-preview-body {
  min-height: 96px;
  padding: 10px 12px;
  color: var(--text);
  font-size: 0.92rem;
  line-height: 1.58;
  overflow: auto;
}

.latex-preview-body p {
  margin: 0 0 10px;
}

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

.latex-preview-empty {
  color: var(--muted);
  font-style: italic;
}

.study-field:nth-child(2) textarea {
  min-height: 138px;
}

.study-field:nth-child(3) textarea {
  min-height: 72px;
}

.study-note {
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.4;
}

.proposal-actions {
  display: flex;
  gap: 8px;
  margin-top: 14px;
}

.node-detail {
  display: grid;
  gap: 14px;
}

.node-title {
  display: grid;
  gap: 4px;
}

.node-title h3 {
  margin: 0;
  font-size: 1.1rem;
}

.node-title p,
.detail-copy {
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.5;
}

.detail-group {
  display: grid;
  gap: 8px;
}

.detail-group h4 {
  margin: 0;
  color: #263340;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.status-controls {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.status-choice {
  min-width: 0;
  min-height: 34px;
  padding: 0 8px;
  font-size: 0.76rem;
}

.status-choice.active {
  border-color: #17202a;
  box-shadow: inset 0 0 0 1px #17202a;
}

.full-width-action {
  width: 100%;
}

.course-view {
  min-width: 0;
}

.course-shell {
  display: grid;
  gap: 16px;
}

.course-library {
  display: grid;
  gap: 16px;
}

.course-library-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.course-card {
  display: grid;
  gap: 14px;
  padding: 18px;
}

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

.course-card h3 {
  margin-top: 10px;
  font-size: 1.12rem;
}

.course-card p {
  color: var(--muted);
  line-height: 1.5;
}

.course-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.course-card-meta span {
  padding: 5px 8px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  background: var(--surface-soft);
  font-size: 0.72rem;
  font-weight: 780;
}

.course-card-link {
  width: fit-content;
  text-decoration: none;
}

.secondary-link {
  display: inline-flex;
  width: fit-content;
  margin-bottom: 10px;
  color: var(--goal);
  font-size: 0.82rem;
  font-weight: 820;
  text-decoration: none;
}

.course-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding: 18px;
}

.course-header h2,
.course-header p,
.course-syllabus h3,
.course-syllabus p,
.course-module h3,
.course-module p {
  margin: 0;
}

.course-header h2 {
  margin-top: 8px;
  font-size: 1.55rem;
}

.course-header p:not(.eyebrow),
.course-syllabus p {
  color: var(--muted);
  line-height: 1.5;
}

.course-progress {
  display: grid;
  gap: 6px;
  width: 180px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.course-progress b {
  font-size: 1.45rem;
}

.course-progress span {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 760;
}

.course-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}

.course-syllabus {
  position: sticky;
  top: 18px;
  display: grid;
  gap: 12px;
  padding: 16px;
}

.course-syllabus h3 {
  font-size: 0.95rem;
}

.course-syllabus ol {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 18px;
}

.course-syllabus li {
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.35;
}

.module-nav {
  display: block;
  width: 100%;
  min-height: 0;
  padding: 0;
  border: 0;
  color: var(--text);
  background: transparent;
  font-weight: 760;
  text-align: left;
  line-height: 1.35;
}

.module-nav.active {
  color: var(--goal);
}

.course-syllabus a {
  color: var(--text);
  font-weight: 760;
  text-decoration: none;
}

.course-syllabus span {
  display: block;
  margin-top: 2px;
  color: var(--unknown);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.course-modules {
  display: grid;
  gap: 16px;
}

.course-module {
  display: grid;
  gap: 14px;
  padding: 20px;
  scroll-margin-top: 16px;
}

.course-module h3 {
  font-size: 1.45rem;
  line-height: 1.15;
}

.course-module .section-head p {
  color: var(--muted);
  font-size: 0.78rem;
}

.course-block,
.course-workbench {
  display: grid;
  gap: 12px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.course-reader {
  border-color: rgba(25, 77, 120, 0.2);
  background: #f8fbff;
}

.course-notes {
  border-color: rgba(89, 70, 42, 0.18);
  background: #fffdf8;
}

.theorem-section {
  border-color: rgba(38, 93, 183, 0.18);
  background: #fbfdff;
}

.course-block h4,
.course-workbench h4 {
  margin: 0;
  color: #263340;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.course-block p {
  color: var(--text);
  font-size: 0.98rem;
  line-height: 1.72;
}

.lesson-document {
  display: grid;
  gap: 14px;
}

.lesson-section {
  display: grid;
  gap: 11px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.lesson-section-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: start;
  gap: 12px;
}

.lesson-section-head span {
  color: var(--goal);
  font-size: 0.72rem;
  font-weight: 840;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.lesson-section-head h4 {
  margin: 0;
  color: var(--text);
  font-size: 1.05rem;
  line-height: 1.25;
  text-transform: none;
  letter-spacing: 0;
}

.section-ask-button {
  min-height: 32px;
  padding: 0 10px;
  white-space: nowrap;
}

.lesson-section p,
.math-statement,
.lesson-problems {
  margin: 0;
  color: var(--text);
  font-size: 1rem;
  line-height: 1.72;
}

.definition-section {
  border-color: rgba(38, 93, 183, 0.2);
  background: #fbfdff;
}

.proposition-section {
  border-color: rgba(21, 129, 91, 0.2);
  background: #fbfffd;
}

.example-section {
  border-color: rgba(89, 70, 42, 0.16);
  background: #fffdf8;
}

.exercises-section,
.assignment-section {
  border-color: rgba(178, 106, 22, 0.24);
  background: var(--learning-soft);
}

.math-statement {
  padding: 11px;
  border: 1px solid rgba(21, 129, 91, 0.18);
  border-radius: 8px;
  background: #ffffff;
}

.lesson-problems {
  display: grid;
  gap: 10px;
  padding-left: 22px;
}

.lesson-problems li {
  display: grid;
  gap: 10px;
  padding-left: 4px;
}

.problem-prompt {
  line-height: 1.65;
}

.problem-prompt p {
  margin: 0;
}

.problem-guidance {
  display: grid;
  gap: 5px;
  margin-top: 8px;
  padding: 10px;
  border: 1px solid rgba(178, 106, 22, 0.18);
  border-radius: 8px;
  background: #fffaf1;
}

.problem-guidance p {
  color: #59462a;
  font-size: 0.88rem;
  line-height: 1.5;
}

.exercise-response,
.section-question,
.module-completion-panel {
  display: grid;
  gap: 10px;
  padding: 12px;
  border: 1px solid rgba(38, 93, 183, 0.16);
  border-radius: 8px;
  background: #ffffff;
}

.exercise-response label,
.section-question label {
  color: #263340;
  font-size: 0.72rem;
  font-weight: 840;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.exercise-response textarea {
  min-height: 156px;
}

.section-question {
  display: none;
  background: var(--goal-soft);
}

.section-question.open {
  display: grid;
}

.section-question textarea {
  min-height: 96px;
}

.module-completion-panel {
  border-color: rgba(21, 129, 91, 0.18);
  background: #fbfffd;
}

.module-completion-panel p {
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.45;
}

.reading-route {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.reading-route span {
  padding: 5px 8px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: #415162;
  background: var(--surface-soft);
  font-size: 0.74rem;
  font-weight: 760;
  line-height: 1.1;
}

.module-study-guide {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 0.72fr);
  gap: 16px;
  padding: 16px;
  border: 1px solid rgba(38, 93, 183, 0.18);
  border-radius: 8px;
  background: #f7fbff;
}

.module-study-guide span {
  color: var(--goal);
  font-size: 0.72rem;
  font-weight: 860;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.module-study-guide h4 {
  margin: 6px 0 8px;
  color: var(--text);
  font-size: 1rem;
  line-height: 1.35;
  text-transform: none;
  letter-spacing: 0;
}

.module-study-guide p,
.module-study-guide li {
  margin: 0;
  color: #415162;
  font-size: 0.9rem;
  line-height: 1.55;
}

.module-study-guide ol {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 20px;
}

.course-workbench {
  border-color: rgba(38, 93, 183, 0.18);
  background: var(--goal-soft);
}

.definition-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.course-module .definition-grid {
  grid-template-columns: 1fr;
}

.definition-card {
  display: grid;
  gap: 5px;
  padding: 11px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.definition-card b {
  color: var(--text);
  font-size: 0.86rem;
}

.definition-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.45;
}

.definition-formula {
  overflow-x: auto;
  padding: 8px;
  border: 1px solid rgba(38, 93, 183, 0.14);
  border-radius: 8px;
  background: #ffffff;
  color: var(--text);
  font-size: 0.92rem;
}

.exercise-stack {
  display: grid;
  gap: 10px;
}

.exercise-card {
  display: grid;
  gap: 5px;
  padding: 11px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.exercise-card span {
  color: var(--goal);
  font-size: 0.72rem;
  font-weight: 820;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.exercise-card p {
  margin: 0;
}

.theorem-stack {
  display: grid;
  gap: 12px;
}

.theorem-card {
  display: grid;
  gap: 10px;
  padding: 13px;
  border: 1px solid rgba(38, 93, 183, 0.18);
  border-radius: 8px;
  background: #ffffff;
}

.theorem-card > div:first-child,
.proof-sketch {
  display: grid;
  gap: 5px;
}

.theorem-card span,
.proof-sketch span {
  color: var(--goal);
  font-size: 0.7rem;
  font-weight: 840;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.theorem-card b {
  color: var(--text);
  font-size: 0.95rem;
}

.theorem-card p {
  margin: 0;
}

.proof-sketch {
  padding: 10px;
  border-left: 3px solid rgba(178, 106, 22, 0.46);
  background: var(--learning-soft);
}

.course-workbench-intro {
  display: grid;
  gap: 4px;
}

.course-workbench-intro h4 {
  margin: 0;
  color: #263340;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.course-workbench-intro p {
  margin: 0;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.45;
}

.course-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.lesson-nav {
  display: flex;
  justify-content: space-between;
  gap: 10px;
}

.feedback-box {
  display: grid;
  gap: 10px;
  padding: 10px;
  border: 1px solid rgba(21, 129, 91, 0.22);
  border-radius: 8px;
  background: var(--known-soft);
}

.feedback-box b,
.proof-review-section h5 {
  color: var(--known);
  font-size: 0.82rem;
}

.feedback-box p,
.feedback-box li {
  margin: 0;
  color: #315f4d;
  font-size: 0.84rem;
  line-height: 1.45;
}

.feedback-title-row {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
}

.feedback-title-row div {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 6px;
}

.feedback-title-row span {
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 760;
}

.readiness-badge {
  padding: 3px 6px;
  border-radius: 999px;
  background: #ffffff;
  border: 1px solid var(--line);
}

.readiness-badge.ready_to_continue {
  color: var(--known);
  border-color: rgba(21, 129, 91, 0.24);
  background: var(--known-soft);
}

.readiness-badge.needs_revision,
.readiness-badge.not_enough_work {
  color: #9a332d;
  border-color: rgba(190, 67, 67, 0.24);
  background: #fff7f6;
}

.proof-review-section {
  display: grid;
  gap: 4px;
}

.proof-review-section h5 {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.proof-review-section ul {
  display: grid;
  gap: 4px;
  margin: 0;
  padding-left: 18px;
}

.proof-review-hint {
  display: grid;
  gap: 4px;
  padding: 9px;
  border: 1px solid rgba(178, 106, 22, 0.22);
  border-radius: 8px;
  background: #fffaf1;
}

.proof-review-hint b {
  color: #8f5711;
}

.feedback-box-loading {
  border-color: rgba(38, 93, 183, 0.22);
  background: #f6f9ff;
}

.feedback-box-loading b,
.feedback-box-loading p {
  color: var(--learning);
}

.feedback-box-error {
  border-color: rgba(190, 67, 67, 0.24);
  background: #fff7f6;
}

.feedback-box-error b,
.feedback-box-error p {
  color: #9a332d;
}

.final-exam-panel {
  display: grid;
  gap: 14px;
  margin-top: 16px;
}

.final-exam-panel.locked {
  background: #f7f8fa;
}

.exam-prompts {
  display: grid;
  gap: 10px;
}

.exam-prompts article {
  display: grid;
  gap: 6px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.exam-prompts span {
  color: var(--learning);
  font-size: 0.72rem;
  font-weight: 860;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.exam-prompts p {
  margin: 0;
  color: var(--text);
  font-size: 0.92rem;
  line-height: 1.55;
}

.toast {
  position: fixed;
  right: 20px;
  bottom: 20px;
  max-width: 340px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #17202a;
  color: #ffffff;
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition:
    opacity 140ms ease,
    transform 140ms ease;
}

.toast.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1120px) {
  .latex-workbench {
    grid-template-columns: 1fr;
  }

  .home-graph-scene::before {
    width: 78vw;
    background: rgba(248, 250, 248, 0.985);
    box-shadow: 92px 0 88px rgba(248, 250, 248, 0.86);
  }

  .home-graph-edges,
  .home-graph-nodes {
    transform: translateX(2%) scale(var(--home-graph-scale, 1));
  }

  .home-graph-edges {
    opacity: 0.38;
  }

  .home-graph-node {
    opacity: 0.58;
  }

  .home-lower {
    grid-template-columns: 1fr;
  }

  .home-principles {
    grid-template-columns: 1fr;
  }

  .home-graph-node {
    min-width: 88px;
    font-size: 0.68rem;
  }

  .app-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: start;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .brand {
    grid-column: 1 / -1;
  }

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

  .right-rail {
    position: static;
    max-height: none;
    overflow: visible;
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .course-layout {
    grid-template-columns: 1fr;
  }

  .course-syllabus {
    position: static;
  }
}

@media (max-width: 760px) {
  .home-nav {
    align-items: flex-start;
    flex-direction: column;
  }

  .home-site-nav {
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .home-enter-small {
    min-height: 36px;
    padding: 0 12px;
  }

  .home-hero {
    min-height: auto;
    padding-top: 42px;
  }

  .home-copy h2 {
    font-size: clamp(2.2rem, 12vw, 3.8rem);
  }

  .home-goal-row {
    grid-template-columns: 1fr;
  }

  .home-actions {
    flex-direction: column;
  }

  .home-actions .secondary-button {
    width: 100%;
  }

  .home-graph-scene {
    height: 760px;
  }

  .home-graph-scene::before {
    width: 86vw;
    background: rgba(248, 250, 248, 0.985);
    box-shadow: 72px 0 68px rgba(248, 250, 248, 0.84);
  }

  .home-graph-edges,
  .home-graph-nodes {
    transform: translateX(8%) scale(var(--home-graph-scale, 1));
  }

  .home-graph-node {
    opacity: 0.5;
  }

  .workspace,
  .sidebar {
    padding: 14px;
  }

  .sidebar,
  .right-rail {
    grid-template-columns: 1fr;
  }

  .topbar {
    display: grid;
  }

  .legend {
    justify-content: flex-start;
  }

  .input-row,
  .metric-row,
  .status-controls,
  .answer-controls {
    grid-template-columns: 1fr;
  }

  .proposal-actions {
    flex-direction: column;
  }

  .course-header {
    display: grid;
  }

  .course-progress {
    width: 100%;
  }

  .course-actions {
    flex-direction: column;
  }

  .lesson-section-head {
    grid-template-columns: 1fr;
  }

  .section-ask-button {
    width: 100%;
  }

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

  .lesson-nav {
    flex-direction: column;
  }
}