:root {
  color-scheme: light dark;
  --paper: #f5ecdf;
  --paper-deep: #ead8c3;
  --paper-bright: #fffaf2;
  --ink: #241816;
  --ink-soft: #63524c;
  --ink-faint: #756158;
  --copper: #a85f38;
  --copper-dark: #7d3f23;
  --ivory: #fff4dc;
  --line: rgba(52, 31, 25, 0.16);
  --line-strong: rgba(52, 31, 25, 0.3);
  --shadow: 0 24px 70px rgba(68, 37, 25, 0.16);
  --display: "Fraunces", Georgia, serif;
  --body: "Manrope", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --radius-sm: 0.75rem;
  --radius-md: 1.25rem;
  --radius-lg: 2rem;
  --max-width: 75rem;
  --section-space: clamp(5.25rem, 8vw, 8rem);
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #171411;
    --paper-deep: #241e1a;
    --paper-bright: #2b241f;
    --ink: #fff5e8;
    --ink-soft: #d2c2b7;
    --ink-faint: #a9968c;
    --copper: #df8d5d;
    --copper-dark: #f0a878;
    --ivory: #3a2e26;
    --line: rgba(255, 241, 224, 0.15);
    --line-strong: rgba(255, 241, 224, 0.28);
    --shadow: 0 28px 80px rgba(0, 0, 0, 0.42);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 6rem;
  scrollbar-gutter: stable;
}

body {
  margin: 0;
  overflow-x: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.2em;
  -webkit-tap-highlight-color: transparent;
}

button,
a,
summary {
  touch-action: manipulation;
}

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

h1,
h2,
h3 {
  font-family: var(--display);
  text-wrap: balance;
}

h1 {
  font-size: clamp(3rem, 6.5vw, 6.3rem);
  font-weight: 650;
  letter-spacing: -0.045em;
  line-height: 0.98;
}

h2 {
  font-size: clamp(2.35rem, 4.6vw, 4.8rem);
  font-weight: 650;
  letter-spacing: -0.035em;
  line-height: 1.02;
}

h3 {
  font-size: clamp(1.35rem, 2vw, 1.8rem);
  font-weight: 650;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

:focus-visible {
  outline: 3px solid var(--copper);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  inset-block-start: 0.5rem;
  inset-inline-start: 0.5rem;
  z-index: 100;
  min-height: 44px;
  padding: 0.65rem 1rem;
  border-radius: 0.5rem;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-150%);
  transition: transform 180ms ease-out;
}

.skip-link:focus {
  transform: translateY(0);
}

.section-shell,
.hero-shell,
.nav-shell,
.footer-shell,
.final-cta-shell {
  width: min(calc(100% - 2rem), var(--max-width));
  margin-inline: auto;
}

.section-shell {
  padding-block: var(--section-space);
}

.eyebrow {
  color: var(--copper-dark);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  line-height: 1.3;
  text-transform: uppercase;
}

.eyebrow span {
  display: inline-block;
  margin-inline-end: 0.35rem;
}

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 50;
  border-block-end: 1px solid transparent;
  background: color-mix(in srgb, var(--paper) 78%, transparent);
  backdrop-filter: blur(18px) saturate(1.25);
  -webkit-backdrop-filter: blur(18px) saturate(1.25);
  transition: border-color 180ms ease-out, box-shadow 180ms ease-out;
}

.site-header.is-scrolled {
  border-color: var(--line);
  box-shadow: 0 10px 30px color-mix(in srgb, var(--ink) 8%, transparent);
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-header {
    background: var(--paper);
  }
}

.nav-shell {
  min-height: 4.75rem;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: clamp(0.75rem, 3vw, 2.5rem);
}

.brand {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand img {
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 0.65rem;
  box-shadow: 0 5px 14px rgba(64, 34, 22, 0.18);
}

.nav-links {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: clamp(0.5rem, 2vw, 1.65rem);
}

.nav-links a {
  position: relative;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  color: var(--ink-soft);
  font-size: 0.86rem;
  font-weight: 600;
  text-decoration: none;
}

.nav-links a::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  inset-block-end: 0.35rem;
  height: 2px;
  border-radius: 99px;
  background: var(--copper);
  transform: scaleX(0);
  transition: transform 180ms ease-out;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--ink);
}

.nav-links a.is-active::after {
  transform: scaleX(1);
}

.nav-cta {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  padding-inline: 1rem;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.78rem;
  font-weight: 700;
  text-decoration: none;
  transition: transform 180ms ease-out, background-color 180ms ease-out;
}

.nav-cta svg {
  width: 0.9rem;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.5;
}

.nav-cta:hover,
.nav-cta:focus-visible {
  transform: translateY(-1px);
  background: var(--copper-dark);
}

.hero {
  position: relative;
  isolation: isolate;
  min-height: calc(100svh - 4.75rem);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
  background:
    radial-gradient(circle at 84% 28%, color-mix(in srgb, var(--copper) 18%, transparent) 0, transparent 29rem),
    var(--paper);
}

.hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  inset: 0;
  opacity: 0.32;
  background-image: url("data:image/svg+xml,%3Csvg width='160' height='160' viewBox='0 0 160 160' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.045'/%3E%3C/svg%3E");
  pointer-events: none;
}

.hero-shell {
  flex: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.07fr) minmax(23rem, 0.93fr);
  align-items: center;
  gap: clamp(3rem, 7vw, 7rem);
  padding-block: clamp(4rem, 8vw, 7.5rem);
}

.hero-copy {
  position: relative;
  z-index: 2;
}

.hero-copy .eyebrow {
  margin-block-end: 1.4rem;
}

.hero-copy h1 {
  max-width: 11.5ch;
}

.hero-deck {
  max-width: 41rem;
  margin-block-start: 1.75rem;
  color: var(--ink-soft);
  font-size: clamp(1.05rem, 1.5vw, 1.22rem);
  line-height: 1.65;
}

.hero-actions {
  margin-block-start: 2rem;
  display: flex;
  align-items: center;
  gap: 1rem 1.25rem;
  flex-wrap: wrap;
}

.store-badge {
  width: 11.25rem;
  min-height: 60px;
  display: inline-flex;
  border-radius: 0.7rem;
  text-decoration: none;
  transition: transform 180ms ease-out, filter 180ms ease-out;
}

.store-badge:hover,
.store-badge:focus-visible {
  transform: translateY(-2px);
  filter: drop-shadow(0 8px 10px rgba(22, 13, 10, 0.22));
}

.compatibility {
  color: var(--ink-faint);
  font-size: 0.78rem;
  font-weight: 600;
}

.engine-note {
  margin-block-start: 1rem;
  color: var(--ink-faint);
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.engine-note span {
  color: var(--ink);
  font-weight: 700;
}

.scholar-orbit {
  position: relative;
  isolation: isolate;
  width: min(100%, 31rem);
  aspect-ratio: 1;
  justify-self: center;
}

.scholar-orbit::before {
  content: "";
  position: absolute;
  z-index: -2;
  inset: 8%;
  border-radius: 50%;
  background: color-mix(in srgb, var(--paper-bright) 82%, transparent);
  box-shadow: inset 0 0 0 1px var(--line), var(--shadow);
}

.scholar-icon {
  position: absolute;
  z-index: 3;
  inset: 24%;
  border: 0.45rem solid color-mix(in srgb, var(--paper-bright) 92%, transparent);
  border-radius: 27%;
  overflow: hidden;
  box-shadow: 0 18px 45px rgba(55, 31, 23, 0.25);
}

.scholar-icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.orbit-ring {
  position: absolute;
  z-index: -1;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
}

.orbit-ring::before,
.orbit-ring::after {
  content: "";
  position: absolute;
  width: 0.42rem;
  height: 0.42rem;
  border-radius: 50%;
  background: var(--copper);
  box-shadow: 0 0 0 0.3rem color-mix(in srgb, var(--copper) 12%, transparent);
}

.orbit-ring-one {
  inset: 12%;
  transform: rotate(13deg);
}

.orbit-ring-one::before {
  inset-block-start: 12%;
  inset-inline-end: 12%;
}

.orbit-ring-one::after {
  inset-block-end: 4%;
  inset-inline-start: 29%;
}

.orbit-ring-two {
  inset: 2%;
  border-style: dashed;
  opacity: 0.64;
  transform: rotate(-16deg);
}

.orbit-ring-two::before {
  inset-block-start: 48%;
  inset-inline-start: -0.2rem;
}

.orbit-ring-two::after {
  inset-block-start: 5%;
  inset-inline-start: 38%;
}

.orbit-note {
  position: absolute;
  z-index: 5;
  min-width: 8.5rem;
  padding: 0.8rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--paper-bright) 92%, transparent);
  box-shadow: 0 10px 28px rgba(65, 36, 24, 0.13);
  transform: rotate(var(--tilt, 0deg));
}

.note-label {
  display: block;
  margin-block-end: 0.22rem;
  color: var(--copper-dark);
  font-size: 0.64rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  line-height: 1.2;
  text-transform: uppercase;
}

.orbit-note strong {
  display: block;
  font-family: var(--display);
  font-size: 0.98rem;
  line-height: 1.2;
}

.note-question {
  --tilt: -4deg;
  inset-block-start: 5%;
  inset-inline-start: -3%;
}

.note-method {
  --tilt: 3deg;
  inset-block-start: 40%;
  inset-inline-end: -9%;
}

.note-result {
  --tilt: -2deg;
  inset-block-end: 5%;
  inset-inline-start: 4%;
}

.orbit-pencil {
  position: absolute;
  z-index: 4;
  width: 3.7rem;
  inset-block-end: 12%;
  inset-inline-end: 11%;
  fill: var(--paper-deep);
  stroke: var(--ink);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
  transform: rotate(4deg);
}

.subject-ribbon {
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  border-block: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper-deep) 72%, var(--paper));
  scrollbar-width: none;
}

.subject-ribbon::-webkit-scrollbar {
  display: none;
}

.subject-ribbon > div {
  min-height: 3.7rem;
  width: max-content;
  min-width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(1.4rem, 4vw, 4.25rem);
  padding-inline: 1.5rem;
  color: var(--ink-soft);
  font-family: var(--display);
  font-size: 0.95rem;
  font-weight: 650;
}

.subject-ribbon span {
  display: inline-flex;
  align-items: center;
  white-space: nowrap;
}

.subject-ribbon span:not(:last-child)::after {
  content: "·";
  margin-inline-start: clamp(1.4rem, 4vw, 4.25rem);
  color: var(--copper);
}

.section-heading {
  max-width: 52rem;
  margin-block-end: clamp(2.8rem, 5vw, 4.5rem);
}

.section-heading .eyebrow,
.how-intro .eyebrow,
.faq-heading .eyebrow {
  margin-block-end: 1rem;
}

.section-heading > p:last-child,
.how-intro > p:last-child,
.faq-heading > p:last-child {
  max-width: 42rem;
  margin-block-start: 1.35rem;
  color: var(--ink-soft);
  font-size: 1.05rem;
}

.features {
  position: relative;
}

.feature-ledger {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 1rem;
}

.feature-dominant,
.feature-row,
.feature-wide {
  border: 1px solid var(--line);
  background: var(--paper-bright);
}

.feature-dominant {
  grid-column: span 8;
  grid-row: span 3;
  min-height: 34rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 2.5rem;
  padding: clamp(1.6rem, 4vw, 3rem);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--copper) 9%, var(--paper-bright)), var(--paper-bright) 55%);
  overflow: hidden;
}

.feature-copy {
  max-width: 39rem;
}

.feature-icon {
  flex: 0 0 auto;
  width: 2.8rem;
  height: 2.8rem;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--paper-deep);
  color: var(--copper-dark);
}

.feature-icon svg {
  width: 1.45rem;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.65;
}

.feature-kicker {
  margin-block-start: 1.4rem;
  color: var(--copper-dark);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.feature-copy h3 {
  max-width: 16ch;
  margin-block-start: 0.5rem;
  font-size: clamp(2rem, 3.7vw, 3.8rem);
}

.feature-copy > p:last-child {
  max-width: 39rem;
  margin-block-start: 1rem;
  color: var(--ink-soft);
}

.solve-sequence {
  display: grid;
  grid-template-columns: minmax(7rem, 1fr) 2.25rem minmax(9rem, 1.2fr) 2.25rem minmax(7rem, 1fr);
  align-items: center;
  gap: 0.55rem;
}

.solve-sequence > div {
  min-height: 6.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--paper) 78%, transparent);
}

.solve-sequence span {
  color: var(--ink-faint);
  font-size: 0.63rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.solve-sequence strong {
  margin-block-start: 0.35rem;
  font-family: var(--display);
  font-size: 1rem;
  line-height: 1.2;
}

.solve-sequence > svg {
  width: 100%;
  fill: none;
  stroke: var(--copper);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.3;
}

.solve-sequence .sequence-answer {
  border-color: color-mix(in srgb, var(--copper) 48%, var(--line));
  background: color-mix(in srgb, var(--copper) 13%, var(--paper-bright));
}

.sequence-answer strong {
  color: var(--copper-dark);
  font-size: 1.35rem;
}

.feature-list {
  grid-column: span 4;
  display: grid;
  gap: 1rem;
}

.feature-row {
  min-height: 10rem;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: start;
  gap: 1rem;
  padding: 1.4rem;
  border-radius: var(--radius-md);
}

.feature-row h3 {
  font-size: 1.3rem;
}

.feature-row p {
  margin-block-start: 0.5rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
  line-height: 1.55;
}

.feature-wide {
  grid-column: span 6;
  min-height: 11rem;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: start;
  gap: 1.25rem;
  padding: clamp(1.4rem, 3vw, 2rem);
  border-radius: var(--radius-md);
}

.feature-wide p {
  max-width: 31rem;
  margin-block-start: 0.55rem;
  color: var(--ink-soft);
}

.feature-subjects {
  background: var(--ink);
  color: var(--paper);
}

.feature-subjects .feature-icon {
  background: color-mix(in srgb, var(--paper) 14%, transparent);
  color: var(--paper-deep);
}

.feature-subjects p {
  color: color-mix(in srgb, var(--paper) 75%, transparent);
}

.how {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(3rem, 8vw, 8rem);
  align-items: start;
}

.how-intro {
  position: sticky;
  inset-block-start: 8rem;
}

.steps {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: study-step;
}

.steps li {
  min-height: 12.5rem;
  display: grid;
  grid-template-columns: 3.25rem 1fr;
  gap: 1.3rem;
  padding-block: 2.5rem;
  border-block-start: 1px solid var(--line-strong);
}

.steps li:last-child {
  border-block-end: 1px solid var(--line-strong);
}

.step-number {
  width: 3rem;
  height: 3rem;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--copper);
  color: #fffaf2;
  font-family: var(--display);
  font-size: 1.25rem;
  font-weight: 650;
}

.steps h3 {
  margin-block-start: 0.2rem;
  font-size: clamp(1.65rem, 2.5vw, 2.3rem);
}

.steps p {
  max-width: 37rem;
  margin-block-start: 0.75rem;
  color: var(--ink-soft);
}

.faq {
  display: grid;
  grid-template-columns: minmax(16rem, 0.7fr) minmax(0, 1.3fr);
  gap: clamp(3rem, 8vw, 8rem);
  align-items: start;
}

.faq-heading {
  position: sticky;
  inset-block-start: 8rem;
}

.faq-list {
  border-block-start: 1px solid var(--line-strong);
}

.faq-list details {
  border-block-end: 1px solid var(--line-strong);
}

.faq-list summary {
  min-height: 5.5rem;
  display: grid;
  grid-template-columns: 1fr 2rem;
  align-items: center;
  gap: 1rem;
  padding-block: 1.3rem;
  cursor: pointer;
  font-family: var(--display);
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  font-weight: 650;
  line-height: 1.25;
  list-style: none;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary span {
  position: relative;
  width: 2rem;
  height: 2rem;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
}

.faq-list summary span::before,
.faq-list summary span::after {
  content: "";
  position: absolute;
  inset-block-start: 50%;
  inset-inline-start: 50%;
  width: 0.7rem;
  height: 1px;
  background: currentColor;
  transform: translate(-50%, -50%);
  transition: transform 180ms ease-out;
}

.faq-list summary span::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.faq-list details[open] summary span::after {
  transform: translate(-50%, -50%) rotate(0);
}

.faq-list summary:hover {
  color: var(--copper-dark);
}

.faq-list details p {
  max-width: 45rem;
  padding-block: 0 1.65rem;
  padding-inline-end: 3rem;
  color: var(--ink-soft);
}

.final-cta {
  padding-block: 1rem;
}

.final-cta-shell {
  position: relative;
  overflow: hidden;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: clamp(1.5rem, 4vw, 3rem);
  padding: clamp(1.6rem, 4vw, 3.5rem);
  border-radius: var(--radius-lg);
  background: var(--ink);
  color: var(--paper);
}

.final-cta-shell::after {
  content: "∫";
  position: absolute;
  inset-block-start: -5rem;
  inset-inline-end: 14rem;
  color: color-mix(in srgb, var(--paper) 7%, transparent);
  font-family: var(--display);
  font-size: 20rem;
  line-height: 1;
  transform: rotate(13deg);
  pointer-events: none;
}

.final-cta-shell > * {
  position: relative;
  z-index: 1;
}

.final-cta-shell > img {
  width: 6rem;
  height: 6rem;
  border-radius: 1.4rem;
}

.final-cta-shell .eyebrow {
  margin-block-end: 0.7rem;
  color: var(--paper-deep);
}

.final-cta-shell h2 {
  max-width: 16ch;
  font-size: clamp(2rem, 4vw, 3.6rem);
}

.site-footer {
  padding-block: 3rem;
}

.footer-shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  color: var(--ink-soft);
  font-size: 0.8rem;
}

.footer-shell p {
  display: flex;
  align-items: center;
  gap: 0.85rem 1.5rem;
  flex-wrap: wrap;
}

.footer-shell strong {
  color: var(--ink);
}

.footer-shell nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.footer-shell a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  font-weight: 700;
}

.not-found {
  min-height: 100svh;
  width: min(calc(100% - 2rem), 58rem);
  margin-inline: auto;
  display: grid;
  place-items: center;
  text-align: center;
}

.not-found img {
  width: 7rem;
  height: 7rem;
  margin-inline: auto;
  border-radius: 1.75rem;
  object-fit: cover;
  box-shadow: var(--shadow);
}

.not-found .eyebrow {
  margin-block: 1.5rem 0.8rem;
}

.not-found h1 {
  font-size: clamp(3rem, 9vw, 6rem);
}

.not-found p:not(.eyebrow) {
  max-width: 34rem;
  margin: 1rem auto 1.8rem;
  color: var(--ink-soft);
}

.home-link {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding-inline: 1.3rem;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-weight: 700;
  text-decoration: none;
  transition: transform 180ms ease-out, background-color 180ms ease-out;
}

.home-link:hover,
.home-link:focus-visible {
  transform: translateY(-1px);
  background: var(--copper-dark);
}

.js.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(1rem);
}

.js.reveal-ready [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 360ms ease-out, transform 360ms ease-out;
}

@media (prefers-reduced-motion: no-preference) {
  .scholar-icon {
    animation: scholar-float 5.5s ease-in-out infinite;
  }

  .orbit-pencil {
    animation: pencil-float 4s ease-in-out infinite 0.7s;
  }

  @keyframes scholar-float {
    0%,
    100% {
      transform: translateY(0) rotate(-0.5deg);
    }
    50% {
      transform: translateY(-0.45rem) rotate(0.5deg);
    }
  }

  @keyframes pencil-float {
    0%,
    100% {
      transform: translateY(0) rotate(4deg);
    }
    50% {
      transform: translateY(-0.35rem) rotate(7deg);
    }
  }
}

@media (max-width: 64rem) {
  .hero {
    min-height: auto;
  }

  .hero-shell {
    grid-template-columns: minmax(0, 1fr) minmax(19rem, 0.85fr);
    gap: 2rem;
  }

  .hero-copy h1 {
    font-size: clamp(3rem, 6vw, 4.7rem);
  }

  .note-question {
    inset-inline-start: 0;
  }

  .note-method {
    inset-inline-end: -2%;
  }

  .feature-dominant {
    grid-column: 1 / -1;
    min-height: 30rem;
  }

  .feature-list {
    grid-column: 1 / -1;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (max-width: 48rem) {
  .nav-shell {
    grid-template-columns: 1fr auto;
  }

  .nav-links {
    display: none;
  }

  .hero-shell {
    grid-template-columns: 1fr;
    gap: 3.5rem;
    padding-block-start: 3.5rem;
  }

  .hero-copy {
    text-align: center;
  }

  .hero-copy h1,
  .hero-deck {
    margin-inline: auto;
  }

  .hero-actions {
    justify-content: center;
  }

  .scholar-orbit {
    width: min(92%, 30rem);
  }

  .subject-ribbon > div {
    justify-content: flex-start;
  }

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

  .feature-row {
    grid-template-columns: auto 1fr;
  }

  .feature-wide {
    grid-column: 1 / -1;
  }

  .how,
  .faq {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .how-intro,
  .faq-heading {
    position: static;
  }

  .final-cta-shell {
    grid-template-columns: auto 1fr;
  }

  .final-cta-shell .store-badge {
    grid-column: 1 / -1;
  }
}

@media (max-width: 35rem) {
  :root {
    --section-space: 4.75rem;
  }

  .section-shell,
  .hero-shell,
  .nav-shell,
  .footer-shell,
  .final-cta-shell {
    width: min(calc(100% - 1.25rem), var(--max-width));
  }

  .brand span {
    max-width: 7.5rem;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .nav-cta {
    padding-inline: 0.85rem;
  }

  .hero-copy h1 {
    font-size: clamp(2.65rem, 13vw, 3.45rem);
  }

  .hero-deck {
    font-size: 1rem;
  }

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

  .scholar-orbit {
    width: 100%;
    margin-block: 0.5rem 1.5rem;
  }

  .scholar-icon {
    inset: 25%;
  }

  .orbit-note {
    min-width: 7.4rem;
    padding: 0.65rem 0.75rem;
  }

  .orbit-note strong {
    font-size: 0.8rem;
  }

  .note-question {
    inset-block-start: 2%;
  }

  .note-method {
    inset-block-start: 40%;
    inset-inline-end: -1%;
  }

  .note-result {
    inset-block-end: 0;
  }

  .feature-dominant {
    min-height: auto;
    padding: 1.35rem;
    border-radius: var(--radius-md);
  }

  .solve-sequence {
    grid-template-columns: 1fr;
    gap: 0.65rem;
  }

  .solve-sequence > svg {
    display: none;
  }

  .solve-sequence > div {
    min-height: 5rem;
  }

  .feature-wide,
  .feature-row {
    grid-template-columns: 1fr;
  }

  .steps li {
    grid-template-columns: 2.8rem 1fr;
    gap: 1rem;
  }

  .step-number {
    width: 2.65rem;
    height: 2.65rem;
  }

  .faq-list summary {
    grid-template-columns: 1fr 2rem;
  }

  .faq-list details p {
    padding-inline-end: 0;
  }

  .final-cta-shell {
    grid-template-columns: 1fr;
    text-align: center;
    justify-items: center;
  }

  .final-cta-shell > img {
    width: 5rem;
    height: 5rem;
  }

  .final-cta-shell .store-badge {
    grid-column: auto;
  }

  .footer-shell {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.75rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .js.reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-contrast: more) {
  :root {
    --ink-soft: var(--ink);
    --ink-faint: var(--ink);
    --line: currentColor;
    --line-strong: currentColor;
  }

  .feature-dominant,
  .feature-row,
  .feature-wide,
  .orbit-note {
    border-width: 2px;
  }
}

@media (forced-colors: active) {
  .site-header {
    background: Canvas;
  }

  .nav-cta,
  .feature-subjects,
  .final-cta-shell {
    border: 2px solid ButtonText;
    background: Canvas;
    color: CanvasText;
  }

  .step-number {
    border: 1px solid ButtonText;
  }
}

:root{--guide-accent:var(--anchor,var(--green,var(--canopy,var(--slate,#2f6fe4))));--guide-ink:var(--ink,var(--text,#17202a));--guide-muted:var(--muted,var(--ink-soft,#5e6b76));--guide-line:var(--line,rgba(20,35,45,.16));--guide-surface:var(--surface-raised,var(--paper-raised,var(--surface,var(--paper,#fff))));--guide-bg:var(--paper,var(--surface,#fff));--guide-tint:var(--anchor-soft,var(--canopy-soft,var(--slate-wash,rgba(50,110,220,.08))))}
/* Arc Tools SEO guide surfaces */
/* Additive, theme-aware resource surfaces used by generated guide hubs. */
.seo-guides{padding:clamp(3rem,7vw,6rem) 0;border-top:1px solid var(--guide-line)}
.seo-guides-inner,.guide-shell{width:min(100% - 2rem,64rem);margin:0 auto}
.seo-guides-kicker,.guide-kicker{margin:0 0 .55rem;color:var(--guide-accent);font-size:.78rem;font-weight:700;letter-spacing:.12em;text-transform:uppercase}
.seo-guides h2,.guide-hero h1,.guide-article h2{color:var(--guide-ink);font-family:var(--display,var(--body,system-ui));line-height:1.08;letter-spacing:-.025em}
.seo-guides h2{max-width:30rem;margin:.2rem 0 .8rem;font-size:clamp(1.7rem,3vw,2.5rem)}
.seo-guides p,.guide-hero p,.guide-article p,.guide-article li{color:var(--guide-muted);line-height:1.7}
.seo-guides-intro{max-width:44rem;margin:0 0 1.4rem}
.seo-guides-links{display:flex;flex-wrap:wrap;gap:.65rem 1rem;margin:1.25rem 0}
.seo-guides-links a,.guide-nav a{color:var(--guide-accent);font-weight:700;text-decoration:underline;text-decoration-thickness:.08em;text-underline-offset:.16em}
.seo-guides-more{display:inline-flex;align-items:center;min-height:2.75rem;padding:.7rem 1rem;border:1px solid var(--guide-line);border-radius:999px;background:var(--guide-surface);color:var(--guide-ink)!important;text-decoration:none!important}
.guide-page{background:var(--guide-bg);color:var(--guide-ink)}
.guide-shell{padding-block:clamp(2rem,6vw,5rem)}
.guide-nav{display:flex;justify-content:space-between;gap:1rem;align-items:center;margin-bottom:clamp(2rem,5vw,4rem);font-size:.95rem}
.guide-nav a:first-child{font-weight:700;text-decoration:none}
.guide-hero{max-width:48rem;margin-bottom:clamp(2.5rem,6vw,5rem)}
.guide-hero h1{margin:.2rem 0 1rem;font-size:clamp(2.1rem,5vw,4.5rem)}
.guide-hero .guide-summary{max-width:42rem;font-size:clamp(1.08rem,1.5vw,1.28rem)}
.guide-index-list{display:grid;gap:1rem;margin:2rem 0 0;padding:0;list-style:none}
.guide-index-list li{margin:0}
.guide-index-link{display:block;padding:1.15rem 1.25rem;border:1px solid var(--guide-line);border-radius:1rem;background:var(--guide-surface);text-decoration:none;transition:transform .2s ease,border-color .2s ease}
.guide-index-link:hover,.guide-index-link:focus-visible{transform:translateY(-2px);border-color:var(--guide-accent)}
.guide-index-link strong{display:block;color:var(--guide-ink);font-size:1.08rem;margin-bottom:.3rem}
.guide-index-link span{color:var(--guide-muted)}
.guide-article{max-width:46rem}
.guide-article h2{margin:2.4rem 0 .75rem;font-size:clamp(1.35rem,2.5vw,2rem)}
.guide-article ul{padding-left:1.2rem}
.guide-article li+li{margin-top:.55rem}
.guide-callout{margin:2rem 0;padding:1.1rem 1.25rem;border-left:3px solid var(--guide-accent);background:var(--guide-tint);border-radius:0 .8rem .8rem 0}
.guide-callout p{margin:0}
.guide-footer-links{display:flex;flex-wrap:wrap;gap:1rem;margin-top:2.5rem;padding-top:1.25rem;border-top:1px solid var(--guide-line)}
@media (min-width:48rem){.seo-guides-inner,.guide-shell{width:min(100% - 4rem,64rem)}}
@media (prefers-reduced-motion:reduce){.guide-index-link{transition:none}.guide-index-link:hover{transform:none}}