:root {
  --ink: #182029;
  --muted: #5f6d78;
  --line: #d7dde2;
  --panel: #ffffff;
  --panel-strong: #f5f7f8;
  --field: #eef2f4;
  --accent: #007f8c;
  --accent-dark: #005e68;
  --accent-soft: #dff4f5;
  --signal: #d94d2b;
  --signal-soft: #fff0e9;
  --metal: #7a8792;
  --dark: #11171d;
  --shadow: 0 20px 60px rgba(17, 23, 29, 0.14);
  color-scheme: light;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: #f8fafb;
  letter-spacing: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select,
textarea {
  font: inherit;
}

.app-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 12px clamp(18px, 4vw, 56px);
  background: rgba(248, 250, 251, 0.9);
  border-bottom: 1px solid rgba(215, 221, 226, 0.9);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 220px;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  color: #fff;
  background: var(--dark);
  border-radius: 6px;
  font-weight: 800;
}

.brand strong,
.brand small {
  display: block;
}

.brand small {
  margin-top: 2px;
  color: var(--muted);
  font-size: 0.75rem;
}

.top-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 700;
}

.top-nav a {
  padding: 10px 13px;
  border-radius: 6px;
}

.top-nav a:hover {
  color: var(--ink);
  background: var(--field);
}

.icon-button {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
}

.menu-button span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: var(--ink);
}

.hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 360px);
  align-items: end;
  min-height: calc(100vh - 72px);
  padding: clamp(72px, 10vw, 140px) clamp(18px, 5vw, 72px) clamp(28px, 6vw, 72px);
  overflow: hidden;
  color: #fff;
  background: var(--dark);
}

.landing {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 520px);
  align-items: center;
  gap: clamp(28px, 5vw, 72px);
  min-height: calc(100vh - 72px);
  padding: clamp(80px, 10vw, 140px) clamp(18px, 5vw, 72px) clamp(58px, 7vw, 92px);
  color: #fff;
  background:
    linear-gradient(120deg, rgba(17, 23, 29, 0.96), rgba(38, 49, 59, 0.92)),
    url("dfam-machine-curriculum-preview.png");
  background-size: cover;
  background-position: center;
}

.landing-content {
  max-width: 820px;
}

.landing h1 {
  margin-bottom: 18px;
}

.landing-copy {
  max-width: 720px;
  color: rgba(255, 255, 255, 0.78);
  font-size: clamp(1rem, 1.8vw, 1.28rem);
  line-height: 1.65;
}

.landing-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  max-width: 620px;
  margin-top: 36px;
}

.landing-metrics div,
.landing-visual {
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(14px);
}

.landing-metrics div {
  padding: 18px;
}

.landing-metrics strong {
  display: block;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 2rem;
}

.landing-metrics span {
  color: rgba(255, 255, 255, 0.72);
}

.landing-visual {
  display: grid;
  gap: 14px;
  padding: 22px;
  box-shadow: 0 30px 90px rgba(0, 0, 0, 0.26);
}

.visual-bar {
  display: flex;
  gap: 8px;
  margin-bottom: 6px;
}

.visual-bar span {
  width: 11px;
  height: 11px;
  border-radius: 999px;
  background: #7de1e7;
}

.visual-row {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 16px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
  background: rgba(17, 23, 29, 0.42);
}

.visual-row span {
  color: rgba(255, 255, 255, 0.68);
}

.visual-row.strong {
  border-color: rgba(125, 225, 231, 0.46);
}

.visual-chart {
  display: flex;
  align-items: end;
  gap: 12px;
  height: 140px;
  padding: 18px;
  border-radius: 8px;
  background: rgba(17, 23, 29, 0.42);
}

.visual-chart span {
  flex: 1;
  min-width: 28px;
  border-radius: 4px 4px 0 0;
  background: linear-gradient(180deg, #7de1e7, #007f8c);
}

#latticeCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero::after {
  position: absolute;
  inset: 0;
  content: "";
  background:
    linear-gradient(90deg, rgba(17, 23, 29, 0.96) 0%, rgba(17, 23, 29, 0.78) 44%, rgba(17, 23, 29, 0.18) 100%),
    linear-gradient(0deg, rgba(17, 23, 29, 0.86) 0%, rgba(17, 23, 29, 0) 42%);
}

.hero-content,
.hero-panel {
  position: relative;
  z-index: 1;
}

.hero-content {
  max-width: 780px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #7de1e7;
}

h1,
h2,
h3,
h4,
p {
  margin-top: 0;
}

h1 {
  max-width: 860px;
  margin-bottom: 20px;
  font-size: clamp(3rem, 7vw, 6.8rem);
  line-height: 0.94;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 16px;
  font-size: clamp(2rem, 4vw, 4.1rem);
  line-height: 1;
  letter-spacing: 0;
}

h3 {
  font-size: clamp(1.35rem, 2vw, 2rem);
  line-height: 1.1;
}

.hero-copy {
  max-width: 680px;
  color: rgba(255, 255, 255, 0.78);
  font-size: clamp(1rem, 1.8vw, 1.28rem);
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 18px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-weight: 800;
  cursor: pointer;
}

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

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

.button.secondary {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.38);
  background: rgba(255, 255, 255, 0.08);
}

.button.ghost {
  color: var(--ink);
  border-color: var(--line);
  background: #fff;
}

.button.ghost:hover {
  background: var(--field);
}

.section .button.secondary,
.quiz .button.secondary {
  color: var(--ink);
  border-color: var(--line);
  background: #fff;
}

.button.full {
  width: 100%;
}

.hero-panel {
  display: grid;
  gap: 12px;
  align-self: end;
  padding-bottom: 12px;
}

.hero-panel div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.24);
  color: rgba(255, 255, 255, 0.68);
}

.hero-panel .metric {
  color: #fff;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 2.5rem;
  font-weight: 700;
}

.section {
  padding: clamp(72px, 10vw, 128px) clamp(18px, 5vw, 72px);
}

.platform-section,
.pricing-section {
  background: #fff;
}

.feature-grid,
.pricing-cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.pricing-cards {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.feature-card,
.pricing-cards article {
  min-height: 260px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.feature-card span,
.pricing-cards span {
  display: inline-block;
  margin-bottom: 18px;
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
}

.feature-card p,
.pricing-cards p {
  color: var(--muted);
  line-height: 1.6;
}

.login-section {
  background: #edf3f5;
}

.login-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 430px);
  gap: 28px;
  align-items: center;
}

.login-panel > div:first-child {
  max-width: 720px;
}

.login-panel p:not(.eyebrow) {
  color: var(--muted);
  line-height: 1.6;
}

.login-status {
  min-height: 20px;
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.5;
  margin: 0;
}

.login-status.success {
  color: var(--accent-dark);
}

.login-status.warning {
  color: #8a3b22;
}

.login-form {
  display: grid;
  gap: 14px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 12px 30px rgba(17, 23, 29, 0.06);
}

.login-feature-list {
  margin: 20px 0 0;
  padding-left: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.login-feature-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.4;
}

.login-feature-list li::before {
  content: "";
  flex-shrink: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
}

.social-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 100%;
  min-height: 46px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--ink);
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 120ms ease, border-color 120ms ease;
}

.social-button:hover {
  background: var(--field);
  border-color: #b0bcc4;
}

.login-divider {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 600;
}

.login-divider::before,
.login-divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

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

.login-field label {
  font-weight: 800;
  font-size: 0.92rem;
}

.login-field input {
  min-height: 46px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--field);
  transition: border-color 120ms ease, box-shadow 120ms ease;
}

.login-field input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 127, 140, 0.14);
}

.login-field-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}

.forgot-link {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
}

.forgot-link:hover {
  text-decoration: underline;
}

.password-wrap {
  position: relative;
}

.password-wrap input {
  width: 100%;
  padding-right: 44px;
}

.toggle-password {
  position: absolute;
  top: 50%;
  right: 12px;
  transform: translateY(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border: none;
  border-radius: 4px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  padding: 0;
}

.toggle-password:hover {
  color: var(--ink);
  background: var(--field);
}

.login-signup-prompt {
  text-align: center;
  font-size: 0.88rem;
  color: var(--muted);
  margin: 0;
}

.login-signup-prompt a {
  color: var(--accent);
  font-weight: 700;
}

.login-signup-prompt a:hover {
  text-decoration: underline;
}

.analytics-section {
  background: #fff;
}

.analytics-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.analytics-card {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.analytics-card span {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 800;
}

.analytics-card strong {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 1.5rem;
}

.analytics-log {
  margin-top: 14px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--field);
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.82rem;
  line-height: 1.6;
}

.analyzer-section {
  background: #f8fafb;
}

.analyzer-layout {
  display: grid;
  grid-template-columns: minmax(300px, 460px) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.analyzer-form,
.analyzer-output,
.model-viewer-card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 12px 30px rgba(17, 23, 29, 0.06);
}

.analyzer-form {
  display: grid;
  gap: 18px;
}

.analyzer-results {
  display: grid;
  gap: 18px;
}

.model-viewer-card {
  display: grid;
  gap: 14px;
}

.model-viewer-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}

.model-viewer-header div {
  display: grid;
  gap: 5px;
}

.model-viewer-header span,
.viewer-hint {
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.76rem;
  font-weight: 800;
  text-transform: uppercase;
}

.model-viewer-header strong {
  color: var(--ink);
}

.viewer-hint {
  color: var(--accent-dark);
}

#partModelCanvas {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  min-height: 260px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(125, 225, 231, 0.12), rgba(217, 77, 43, 0.08)),
    #11171d;
  cursor: grab;
}

#partModelCanvas:active {
  cursor: grabbing;
}

.file-drop {
  display: grid;
  gap: 8px;
  padding: 22px;
  border: 1px dashed var(--accent);
  border-radius: 8px;
  background: var(--accent-soft);
  cursor: pointer;
}

.file-drop span {
  color: var(--accent-dark);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.file-drop strong {
  color: var(--ink);
}

.file-drop input {
  width: 100%;
}

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

.analyzer-form label:not(.file-drop) {
  display: grid;
  gap: 8px;
  min-width: 0;
  font-weight: 800;
}

.analyzer-form input,
.analyzer-form select {
  width: 100%;
  min-width: 0;
  min-height: 46px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--field);
}

.analyzer-note {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.5;
}

.empty-analysis {
  display: grid;
  min-height: 420px;
  align-content: center;
  justify-items: center;
  text-align: center;
}

.empty-analysis span {
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
}

.empty-analysis p {
  max-width: 420px;
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.analysis-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 18px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.analysis-header span {
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.analysis-header h3 {
  margin: 6px 0 0;
}

.confidence-badge {
  min-width: 108px;
  padding: 10px;
  border-radius: 8px;
  color: var(--accent-dark);
  background: var(--accent-soft);
  text-align: center;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-weight: 800;
}

.geometry-grid,
.recommendation-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.geometry-card,
.recommendation-card {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.geometry-card span,
.recommendation-card span {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.geometry-card strong,
.recommendation-card strong {
  font-family: "JetBrains Mono", ui-monospace, monospace;
}

.analysis-block {
  margin-top: 16px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.analysis-block h4 {
  margin-bottom: 10px;
}

.analysis-block li,
.analysis-block p {
  color: var(--muted);
  line-height: 1.55;
}

.analysis-block ul,
.analysis-block ol {
  margin-bottom: 0;
  padding-left: 20px;
}

.section-heading {
  max-width: 920px;
  margin-bottom: 38px;
}

.section-heading p:not(.eyebrow) {
  max-width: 760px;
  color: var(--muted);
  font-size: 1.08rem;
  line-height: 1.65;
}

.section-heading.compact {
  max-width: 760px;
}

.course-shell {
  background: #fff;
}

.course-layout {
  display: grid;
  grid-template-columns: minmax(230px, 320px) minmax(0, 1fr);
  gap: 28px;
}

.module-list {
  display: grid;
  align-content: start;
  gap: 8px;
}

.module-tab {
  display: grid;
  grid-template-columns: 42px 1fr;
  align-items: center;
  gap: 12px;
  min-height: 54px;
  padding: 10px 12px;
  color: var(--muted);
  text-align: left;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  cursor: pointer;
}

.module-tab span {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  color: var(--metal);
}

.module-tab.active {
  color: var(--ink);
  border-color: var(--accent);
  background: var(--accent-soft);
}

.lesson-view {
  min-height: 560px;
  padding: clamp(24px, 4vw, 48px);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.lesson-kicker {
  margin-bottom: 12px;
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.84rem;
  font-weight: 700;
}

.lesson-view > p {
  color: var(--muted);
  font-size: 1.08rem;
  line-height: 1.65;
}

.lesson-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin: 28px 0;
}

.lesson-card {
  min-height: 180px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.lesson-card strong {
  display: block;
  margin-bottom: 10px;
  font-size: 1rem;
}

.lesson-card p {
  color: var(--muted);
  line-height: 1.55;
}

.checkpoint {
  padding: 22px;
  border-left: 4px solid var(--signal);
  border-radius: 8px;
  background: var(--signal-soft);
}

.checkpoint h4 {
  margin-bottom: 8px;
}

.checkpoint p {
  margin-bottom: 0;
  color: #75402f;
  line-height: 1.55;
}

.split-section {
  background: #f8fafb;
}

.lab-grid {
  display: grid;
  grid-template-columns: minmax(280px, 420px) minmax(0, 1fr);
  gap: 24px;
  align-items: stretch;
}

.calculator,
.admin-form,
.admin-output,
.results,
.tool-detail,
.quiz {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 12px 30px rgba(17, 23, 29, 0.06);
}

.calculator label,
.admin-form label {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 14px;
  margin-bottom: 14px;
  color: var(--ink);
  font-weight: 800;
}

.calculator label span,
.admin-form label span {
  color: var(--muted);
  font-weight: 600;
}

.calculator input,
.calculator select,
.admin-form input,
.admin-form select {
  grid-column: 1 / -1;
  width: 100%;
  min-height: 46px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--field);
}

.results {
  display: grid;
  align-content: start;
  gap: 18px;
}

.result-row {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.result-row strong,
.risk-meter strong {
  font-family: "JetBrains Mono", ui-monospace, monospace;
}

.risk-meter {
  display: grid;
  gap: 10px;
}

.meter-track {
  height: 14px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--field);
}

.meter-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #f1b849, var(--signal));
  transition: width 220ms ease;
}

#costAdvice {
  max-width: 720px;
  color: var(--muted);
  line-height: 1.65;
}

.process-section {
  background: var(--dark);
  color: #fff;
}

.process-section .section-heading p {
  color: #7de1e7;
}

.process-grid {
  display: grid;
  grid-template-columns: repeat(7, minmax(190px, 1fr));
  gap: 16px;
  overflow-x: auto;
  padding-bottom: 8px;
}

.process-card {
  min-height: 430px;
  padding: 24px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.06);
}

.process-icon {
  display: inline-grid;
  place-items: center;
  width: 54px;
  height: 54px;
  margin-bottom: 22px;
  color: #11171d;
  background: #7de1e7;
  border-radius: 6px;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-weight: 800;
}

.process-card p,
.process-card li {
  color: rgba(255, 255, 255, 0.75);
  line-height: 1.55;
}

.process-card ul {
  padding-left: 18px;
}

.tools-section {
  background: #fff;
}

.tool-board {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 20px;
}

.tool-chip {
  min-height: 42px;
  padding: 0 14px;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  cursor: pointer;
}

.tool-chip.active {
  color: #fff;
  border-color: var(--accent);
  background: var(--accent);
}

.tool-detail {
  min-height: 280px;
}

.tool-detail h3 {
  margin-bottom: 12px;
}

.tool-detail p {
  color: var(--muted);
  line-height: 1.65;
}

.template-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 18px;
}

.template-item {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.template-item span {
  display: block;
  margin-bottom: 8px;
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.8rem;
  font-weight: 700;
}

.quiz-section {
  background: #edf3f5;
}

.quiz {
  max-width: 860px;
}

.quiz-question {
  font-size: 1.25rem;
  font-weight: 800;
  line-height: 1.45;
}

.quiz-options {
  display: grid;
  gap: 10px;
  margin: 18px 0;
}

.quiz-option {
  min-height: 50px;
  padding: 12px 14px;
  text-align: left;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  cursor: pointer;
}

.quiz-option.correct {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.quiz-option.incorrect {
  border-color: var(--signal);
  background: var(--signal-soft);
}

.quiz-feedback {
  min-height: 48px;
  color: var(--muted);
  line-height: 1.55;
}

.admin-section {
  background: #f8fafb;
}

.admin-layout {
  display: grid;
  grid-template-columns: minmax(300px, 430px) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

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

.admin-group {
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.admin-group:last-of-type {
  border-bottom: 0;
}

.admin-group h3 {
  margin-bottom: 16px;
  font-size: 1.05rem;
}

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

.machine-grid {
  display: grid;
  gap: 10px;
}

.machine-grid label {
  display: grid;
  grid-template-columns: 18px 1fr;
  align-items: start;
  gap: 12px;
  min-height: 76px;
  margin: 0;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.machine-grid input {
  width: 16px;
  min-height: 16px;
  margin-top: 3px;
}

.machine-grid strong,
.machine-grid small {
  display: block;
}

.machine-grid small {
  margin-top: 4px;
  color: var(--muted);
  line-height: 1.35;
}

.pricing-grid {
  display: grid;
  gap: 12px;
}

.check-grid label {
  display: flex;
  align-items: center;
  min-height: 44px;
  margin: 0;
  padding: 10px 12px;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel-strong);
  font-weight: 700;
}

.check-grid input {
  width: 16px;
  min-height: 16px;
  margin: 0 8px 0 0;
}

.admin-output {
  min-height: 720px;
  background: #fff;
}

.admin-output-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.admin-output-header span {
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
}

.admin-output-header strong {
  font-size: 1.1rem;
}

.admin-status {
  margin: -6px 0 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.45;
}

.admin-status.warning {
  color: #8a3b22;
}

.admin-status.success {
  color: var(--accent-dark);
}

.plan-summary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-bottom: 18px;
}

.plan-stat {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.plan-stat span {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 800;
}

.plan-stat strong {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 1.35rem;
}

.pricing-breakdown {
  display: grid;
  gap: 10px;
}

.pricing-row {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.pricing-row:last-child {
  border-bottom: 0;
}

.pricing-row span {
  color: var(--muted);
}

.pricing-row strong {
  font-family: "JetBrains Mono", ui-monospace, monospace;
}

.plan-block {
  margin-top: 14px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.plan-block h4 {
  margin-bottom: 10px;
}

.plan-block p,
.plan-block li {
  color: var(--muted);
  line-height: 1.55;
}

.plan-block ul,
.plan-block ol {
  margin-bottom: 0;
  padding-left: 20px;
}

.process-pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}

.process-pill {
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--accent-dark);
  background: var(--accent-soft);
  font-weight: 800;
}

.phase-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.phase-card {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.phase-card span {
  display: block;
  margin-bottom: 8px;
  color: var(--accent);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 800;
}

.phase-card strong {
  display: block;
  margin-bottom: 8px;
}

.phase-card p {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.5;
}

.rubric-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.rubric-item {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.rubric-item strong {
  display: block;
  margin-bottom: 6px;
}

.rubric-item span {
  color: var(--muted);
  line-height: 1.45;
}

.machine-card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 12px;
}

.machine-card {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.machine-card h5 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.machine-card p,
.machine-card li {
  color: var(--muted);
  line-height: 1.48;
}

.machine-card ul {
  margin: 10px 0 0;
  padding-left: 18px;
}

.export-panel {
  margin-top: 18px;
}

.export-panel label {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.export-panel textarea {
  width: 100%;
  min-height: 220px;
  padding: 14px;
  resize: vertical;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--field);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.82rem;
  line-height: 1.55;
}

.course-builder-panel {
  margin-top: 18px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.course-builder-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.course-builder-actions span {
  display: block;
  margin-bottom: 5px;
  color: var(--muted);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.course-builder-actions strong {
  font-size: 1rem;
}

.tailored-course-grid {
  display: grid;
  gap: 12px;
}

.tailored-course-card {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-strong);
}

.tailored-course-card h5 {
  margin: 0 0 8px;
  font-size: 1rem;
}

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

.tailored-course-card ul {
  margin: 10px 0 0;
  padding-left: 18px;
}

.session-tag {
  display: inline-block;
  margin-bottom: 10px;
  padding: 6px 8px;
  border-radius: 999px;
  color: var(--accent-dark);
  background: var(--accent-soft);
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 0.76rem;
  font-weight: 800;
}

.capstone {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 430px);
  gap: 36px;
  align-items: center;
  color: #fff;
  background: #26313b;
}

.capstone p:not(.eyebrow) {
  max-width: 760px;
  color: rgba(255, 255, 255, 0.76);
  line-height: 1.65;
}

.capstone-steps {
  display: grid;
  gap: 10px;
}

.capstone-steps span {
  padding: 16px;
  border-left: 4px solid #7de1e7;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.08);
  font-weight: 800;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 26px clamp(18px, 5vw, 72px);
  color: var(--muted);
  border-top: 1px solid var(--line);
  background: #fff;
}

@media (max-width: 1080px) {
  .lesson-grid,
  .pricing-cards,
  .template-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .hero,
  .landing {
    grid-template-columns: 1fr;
  }

  .hero-panel {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    margin-top: 48px;
  }

  .hero-panel div {
    display: grid;
    justify-content: start;
  }
}

@media (max-width: 820px) {
  .top-nav {
    position: absolute;
    top: 72px;
    right: 18px;
    left: 18px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: var(--shadow);
  }

  .top-nav.open {
    display: flex;
  }

  .icon-button {
    display: block;
  }

  .course-layout,
  .lab-grid,
  .analyzer-layout,
  .admin-layout,
  .login-panel,
  .capstone {
    grid-template-columns: 1fr;
  }

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

  .module-tab {
    grid-template-columns: 32px 1fr;
    min-height: 64px;
  }

  .hero-panel,
  .feature-grid,
  .analytics-grid,
  .geometry-grid,
  .recommendation-grid,
  .lesson-grid,
  .template-grid,
  .phase-grid,
  .rubric-grid,
  .machine-card-grid,
  .plan-summary {
    grid-template-columns: 1fr;
  }

  .site-footer {
    display: grid;
  }

  .course-builder-actions {
    align-items: stretch;
    flex-direction: column;
  }
}

@media (max-width: 520px) {
  .app-header {
    min-height: 66px;
  }

  .brand {
    min-width: 0;
  }

  .brand small {
    display: none;
  }

  .top-nav {
    top: 66px;
  }

  .hero {
    min-height: calc(100vh - 66px);
    padding-top: 64px;
  }

  .landing {
    min-height: calc(100vh - 66px);
    padding-top: 64px;
  }

  .hero-actions {
    display: grid;
  }

  .landing-metrics,
  .pricing-cards {
    grid-template-columns: 1fr;
  }

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

  .lesson-view,
  .calculator,
  .analyzer-form,
  .analyzer-output,
  .model-viewer-card,
  .admin-form,
  .admin-output,
  .results,
  .tool-detail,
  .quiz {
    padding: 18px;
  }

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

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

  .analysis-header {
    display: grid;
  }
}