/* ========================================
   YOUR ANSWER — DESIGN FOUNDATION
   ======================================== */

:root {
  color-scheme: light dark;

  /* Brand */
  --color-brand: #3157d5;
  --color-brand-hover: #2446b8;
  --color-brand-soft: #e8edff;

  /* Light theme */
  --color-bg: #f5f7fc;
  --color-surface: #ffffff;
  --color-surface-alt: #edf1f8;
  --color-text: #182238;
  --color-text-muted: #647089;
  --color-border: #dfe5ef;

  /* Status colors */
  --color-success: #16845b;
  --color-warning: #b7791f;
  --color-danger: #c24141;

  /* Layout */
  --page-width: 1440px;
  --header-height: 68px;
  --sidebar-width: 250px;

  /* Spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;

  /* Shape and depth */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-pill: 999px;

  --shadow-card: 0 4px 18px rgb(30 45 80 / 7%);

  /* Motion */
  --transition-fast: 160ms ease;
}

/* Dark theme */
html[data-theme="dark"] {
  color-scheme: dark;

  --color-brand: #8da6ff;
  --color-brand-hover: #a8baff;
  --color-brand-soft: #27365e;

  --color-bg: #111827;
  --color-surface: #1b2536;
  --color-surface-alt: #263247;
  --color-text: #edf2ff;
  --color-text-muted: #a8b4cb;
  --color-border: #344158;

  --color-success: #65d6a4;
  --color-warning: #f4c56b;
  --color-danger: #ff9292;

  --shadow-card: 0 4px 22px rgb(0 0 0 / 18%);
}

/* Consistent sizing */
* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;

  background: var(--color-bg);
  color: var(--color-text);

  font-family:
    system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;

  font-size: 16px;
  line-height: 1.6;

  transition:
    background-color var(--transition-fast),
    color var(--transition-fast);
}

/* Images and controls */
img,
svg,
canvas {
  max-width: 100%;
}

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

button {
  cursor: pointer;
}

a {
  color: var(--color-brand);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 3px solid var(--color-brand);
  outline-offset: 3px;
}

/* Shared layout helpers */
.container {
  width: min(100% - 32px, var(--page-width));
  margin-inline: auto;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.muted {
  color: var(--color-text-muted);
}

[hidden] {
  display: none !important;
}

/* Respect reduced-motion preferences */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}


/* ========================================
   YOUR ANSWER — INITIAL PAGE LAYOUT
   ======================================== */

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text);
  text-decoration: none;
  flex-shrink: 0;
}

.brand:hover {
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: var(--color-brand);
  color: white;
  font-size: 24px;
  font-weight: 800;
}

.brand-copy {
  display: grid;
  line-height: 1.3;
}

.brand-copy strong {
  font-size: 17px;
}

.brand-copy small {
  color: var(--color-text-muted);
  font-size: 11px;
}

.top-nav,
.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.top-nav a {
  padding: 9px 10px;
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 600;
}

.top-nav a:hover {
  color: var(--color-brand);
  text-decoration: none;
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 9px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 13px;
  font-weight: 600;
}

.icon-button:hover {
  background: var(--color-surface-alt);
}

.menu-toggle,
.mobile-nav {
  display: none;
}

/* Welcome section */
.welcome-section {
  margin-top: 36px;
  padding: clamp(28px, 6vw, 64px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(
      circle at 90% 10%,
      var(--color-brand-soft),
      transparent 45%
    ),
    var(--color-surface);
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--color-brand);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 1.4px;
}

.welcome-section h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(34px, 6vw, 62px);
  line-height: 1.12;
  letter-spacing: -1.8px;
}

.welcome-description {
  max-width: 620px;
  margin: 20px 0 26px;
  color: var(--color-text-muted);
  font-size: clamp(15px, 2vw, 18px);
}

.primary-button {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 12px 18px;
  border-radius: var(--radius-sm);
  background: var(--color-brand);
  color: #ffffff;
  font-weight: 700;
  transition: transform var(--transition-fast);
}

.primary-button:hover {
  color: #ffffff;
  text-decoration: none;
  transform: translateY(-2px);
}

/* Section headings */
.section {
  padding-top: 56px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}

.section-heading h2,
.lab-preview h2 {
  margin: 0;
  font-size: clamp(24px, 3vw, 34px);
  line-height: 1.25;
}

.section-heading > p {
  margin: 0;
}

/* Responsive card grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.feature-card {
  min-width: 0;
  padding: 22px;
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast);
}

.feature-card:hover {
  transform: translateY(-3px);
  border-color: var(--color-brand);
}

.feature-icon {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  margin-bottom: 18px;
  border-radius: 14px;
  background: var(--color-brand-soft);
  color: var(--color-brand);
  font-size: 23px;
  font-weight: 800;
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.feature-card p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 14px;
}

/* Learning lab preview */
.lab-preview {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: clamp(24px, 5vw, 44px);
}

.lab-preview > div {
  max-width: 650px;
}

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

.lab-symbol {
  flex-shrink: 0;
  color: var(--color-brand);
  font-size: clamp(60px, 10vw, 100px);
}

/* Footer */
.site-footer {
  margin-top: 64px;
  padding: 28px 0;
  border-top: 1px solid var(--color-border);
}

.site-footer p {
  margin: 5px 0;
  font-size: 14px;
}

/* Tablet */
@media (max-width: 900px) {
  .feature-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .top-nav {
    gap: 2px;
  }

  .top-nav a {
    padding-inline: 6px;
  }

  .brand-copy small {
    display: none;
  }
}

/* Mobile */
@media (max-width: 620px) {
  .container {
    width: calc(100% - 28px);
  }

  .header-inner {
    min-height: 64px;
    gap: 8px;
  }

  .brand-mark {
    width: 36px;
    height: 36px;
    font-size: 20px;
  }

  .brand-copy strong {
    font-size: 15px;
  }

  .top-nav {
    display: none;
  }

  .header-actions {
    gap: 6px;
  }

  .icon-button {
    padding: 9px;
  }

  .menu-toggle {
    display: inline-flex;
  }

  .mobile-nav:not([hidden]) {
    display: flex;
    flex-direction: column;
    padding-top: 8px;
    padding-bottom: 14px;
  }

  .mobile-nav a {
    padding: 10px 4px;
    color: var(--color-text);
    border-bottom: 1px solid var(--color-border);
  }

  .welcome-section {
    margin-top: 20px;
    padding: 28px 22px;
  }

  .welcome-section h1 {
    letter-spacing: -0.8px;
  }

  .section {
    padding-top: 38px;
  }

  .section-heading {
    align-items: start;
    flex-direction: column;
    gap: 8px;
  }

  .feature-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .feature-card {
    padding: 20px;
  }

  .lab-preview {
    align-items: start;
  }

  .lab-symbol {
    font-size: 48px;
  }

  .site-footer {
    margin-top: 44px;
  }
}


/* ========================================
   WELCOME SECTION — EDITORIAL + VISUAL
   ======================================== */

.welcome-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.9fr);
  align-items: center;
  gap: clamp(32px, 6vw, 80px);
  padding-top: clamp(56px, 9vw, 112px);
  padding-bottom: clamp(64px, 9vw, 112px);
}

.welcome-content {
  min-width: 0;
}

.welcome-section h1 {
  max-width: 650px;
  margin: 18px 0;
  font-size: clamp(2.5rem, 5.5vw, 4.7rem);
  line-height: 1.08;
  letter-spacing: -0.055em;
}

.welcome-highlight {
  display: block;
  color: var(--color-brand);
}

.welcome-description {
  max-width: 540px;
  font-size: 1.08rem;
  line-height: 1.85;
  color: var(--color-text-muted);
}

.welcome-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 22px;
  margin-top: 30px;
}

.secondary-link {
  color: var(--color-text);
  font-weight: 600;
  text-decoration: none;
}

.secondary-link:hover {
  color: var(--color-brand);
}

.welcome-note {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 30px;
  color: var(--color-text-muted);
  font-size: 0.88rem;
}

.welcome-note-dot {
  width: 9px;
  height: 9px;
  flex: 0 0 9px;
  border-radius: 50%;
  background: var(--color-success);
}

/* Learning illustration */

.welcome-visual {
  position: relative;
  display: grid;
  place-items: center;
  width: 100%;
  max-width: 480px;
  aspect-ratio: 1;
  justify-self: center;
  isolation: isolate;
}

.welcome-visual::before {
  content: "";
  position: absolute;
  inset: 12%;
  z-index: -2;
  border-radius: 50%;
  background:
    radial-gradient(
      circle,
      var(--color-brand-soft),
      transparent 70%
    );
}

.visual-orbit {
  position: absolute;
  width: 76%;
  height: 76%;
  border: 1px solid var(--color-border);
  border-radius: 50%;
}

.orbit-one {
  transform: rotate(-25deg) scaleY(0.78);
}

.orbit-two {
  transform: rotate(55deg) scaleY(0.78);
}

.visual-core {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 39%;
  aspect-ratio: 1;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  text-align: center;
}

.visual-core-symbol {
  display: grid;
  place-items: center;
  width: 58px;
  height: 58px;
  border-radius: 19px;
  background: var(--color-brand);
  color: white;
  font-size: 2rem;
  font-weight: 800;
}

.visual-core-label {
  max-width: 125px;
  color: var(--color-text-muted);
  font-size: 0.55rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.visual-node {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 12px 15px;
  border: 1px solid var(--color-border);
  border-radius: 15px;
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  font-size: 0.9rem;
  font-weight: 650;
  white-space: nowrap;
}

.visual-node-icon {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--color-surface-alt);
  color: var(--color-brand);
  font-size: 1.2rem;
}

.node-science {
  top: 12%;
  left: 0;
}

.node-math {
  top: 18%;
  right: 0;
}

.node-code {
  right: 0;
  bottom: 17%;
}

.node-discover {
  bottom: 10%;
  left: 3%;
}

/* Responsive layout */

@media (max-width: 900px) {
  .welcome-section {
    grid-template-columns: 1fr 0.8fr;
    gap: 24px;
  }

  .visual-node {
    gap: 6px;
    padding: 9px 10px;
    font-size: 0.78rem;
  }

  .visual-node-icon {
    width: 29px;
    height: 29px;
  }
}

@media (max-width: 680px) {
  .welcome-section {
    grid-template-columns: 1fr;
    gap: 28px;
    padding-top: 52px;
  }

  .welcome-section h1 {
    font-size: clamp(2.6rem, 11vw, 3.8rem);
  }

  .welcome-visual {
    width: 100%;
    max-width: 390px;
  }

  .welcome-actions {
    gap: 18px;
  }
}

@media (max-width: 380px) {
  .visual-node {
    padding: 7px;
    font-size: 0.7rem;
  }

  .visual-node-icon {
    width: 25px;
    height: 25px;
  }

  .visual-core-label {
    font-size: 0.45rem;
  }
}

/* ========================================
   FEATURED DISCOVERY
   ======================================== */

.featured-discovery {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
  gap: 32px;
  min-height: 300px;
  padding: clamp(24px, 5vw, 48px);
  overflow: hidden;
}

.featured-content {
  position: relative;
  z-index: 1;
}

.featured-tag {
  display: inline-block;
  padding: 7px 11px;
  border-radius: 999px;
  background: var(--color-brand-soft);
  color: var(--color-brand);
  font-size: 0.78rem;
  font-weight: 700;
}

.featured-content h3 {
  max-width: 500px;
  margin: 18px 0 12px;
  font-size: clamp(1.65rem, 3vw, 2.5rem);
  line-height: 1.2;
  letter-spacing: -0.035em;
}

.featured-content p {
  max-width: 500px;
  margin-bottom: 24px;
  color: var(--color-text-muted);
  line-height: 1.8;
}

.featured-visual {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 240px;
  height: 100%;
  min-width: 0;
  border-radius: var(--radius-xl);
  background:
    radial-gradient(
      circle at center,
      var(--color-brand-soft),
      transparent 70%
    );
}

.featured-orbit {
  width: 180px;
  height: 180px;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  box-shadow:
    0 0 0 24px var(--color-surface),
    0 0 0 25px var(--color-border);
}

.featured-object {
  position: absolute;
  width: 62px;
  height: 62px;
  border: 8px solid var(--color-brand);
  border-radius: 50%;
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.featured-vector {
  position: absolute;
  color: var(--color-brand);
  font-size: 2.5rem;
  font-weight: 800;
}

.vector-one {
  top: 20%;
  right: 18%;
  transform: rotate(-25deg);
}

.vector-two {
  bottom: 15%;
  left: 18%;
  transform: rotate(15deg);
}

/* ========================================
   RANDOM QUOTATION
   ======================================== */

.thought-card {
  position: relative;
  padding: clamp(28px, 6vw, 64px);
  text-align: center;
  overflow: hidden;
}

.thought-card::before {
  content: "“";
  position: absolute;
  top: -38px;
  left: 20px;
  color: var(--color-brand-soft);
  font-size: 12rem;
  line-height: 1;
  font-family: Georgia, serif;
  pointer-events: none;
}

.thought-label {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  color: var(--color-brand);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
}

.thought-label span {
  font-size: 1.15rem;
}

#quote-text {
  position: relative;
  max-width: 780px;
  margin: 28px auto 18px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.55rem, 3.5vw, 2.6rem);
  font-weight: 500;
  line-height: 1.45;
  letter-spacing: -0.025em;
}

.quote-author {
  margin-bottom: 28px;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 11px 18px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-text);
  font: inherit;
  font-size: 0.9rem;
  font-weight: 650;
  cursor: pointer;
  transition:
    background var(--transition-fast),
    border-color var(--transition-fast),
    transform var(--transition-fast);
}

.secondary-button:hover {
  border-color: var(--color-brand);
  background: var(--color-brand-soft);
}

.secondary-button:active {
  transform: translateY(1px);
}

/* ========================================
   ABOUT YOUR ANSWER PREVIEW
   ======================================== */

.about-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: start;
  gap: clamp(28px, 6vw, 80px);
  padding: clamp(24px, 5vw, 48px) 0;
}

.about-preview h2 {
  max-width: 540px;
  margin-top: 14px;
  font-size: clamp(1.9rem, 4vw, 3rem);
  line-height: 1.2;
  letter-spacing: -0.04em;
}

.about-preview-text {
  max-width: 560px;
  color: var(--color-text-muted);
  line-height: 1.85;
}

.about-preview-text p + p {
  margin-top: 16px;
}

.about-preview-text .secondary-link {
  display: inline-block;
  margin-top: 12px;
  color: var(--color-brand);
}

/* Keep the new sections comfortable on tablets and phones */

@media (max-width: 680px) {
  .featured-discovery {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .featured-visual {
    min-height: 220px;
  }

  .about-preview {
    grid-template-columns: 1fr;
    gap: 18px;
  }

  .thought-card::before {
    left: 4px;
    font-size: 8rem;
  }
}



/* ========================================
   SUBJECTS CATALOGUE PAGE
   ======================================== */

.page-intro {
  padding-top: clamp(52px, 8vw, 96px);
  padding-bottom: 28px;
}

.page-intro h1 {
  max-width: 850px;
  margin: 14px 0 18px;
  font-size: clamp(2.4rem, 5.5vw, 4.2rem);
  line-height: 1.1;
  letter-spacing: -0.05em;
}

.page-intro > p:last-child {
  max-width: 680px;
  color: var(--color-text-muted);
  font-size: 1.05rem;
  line-height: 1.85;
}

.subjects-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.subject-card {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: start;
  gap: 18px;
  min-width: 0;
  padding: 24px;
  color: var(--color-text);
  text-decoration: none;
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast);
}

.subject-card:hover {
  transform: translateY(-3px);
  border-color: var(--color-brand);
}

.subject-symbol {
  display: grid;
  place-items: center;
  width: 54px;
  height: 54px;
  border-radius: 16px;
  background: var(--color-brand-soft);
  color: var(--color-brand);
  font-size: 1.55rem;
  font-weight: 750;
}

.subject-card h3 {
  margin: 3px 0 9px;
  font-size: 1.2rem;
  line-height: 1.4;
}

.subject-card p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.92rem;
  line-height: 1.75;
}

.subject-arrow {
  align-self: center;
  color: var(--color-brand);
  font-size: 1.4rem;
  transition: transform var(--transition-fast);
}

.subject-card:hover .subject-arrow {
  transform: translateX(4px);
}

/* Recently selected subject */

.recent-subject-section {
  padding-top: 12px;
}

.recent-subject-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px;
  border: 1px solid var(--color-brand);
  border-radius: var(--radius-lg);
  background: var(--color-brand-soft);
  color: var(--color-text);
  text-decoration: none;
  transition: transform var(--transition-fast);
}

.recent-subject-card:hover {
  transform: translateY(-2px);
}

.recent-subject-card .subject-symbol {
  flex: 0 0 auto;
  background: var(--color-surface);
}

.recent-subject-info {
  flex: 1;
  min-width: 0;
}

.recent-subject-info h3 {
  margin-bottom: 6px;
}

.recent-subject-info p {
  margin: 0;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.recent-subject-label {
  display: block;
  margin-bottom: 5px;
  color: var(--color-brand);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

/* Future subject notice */

.coming-soon {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: clamp(24px, 5vw, 40px);
}

.coming-soon h2 {
  margin: 12px 0;
  font-size: clamp(1.5rem, 3vw, 2rem);
}

.coming-soon p:last-child {
  max-width: 620px;
  line-height: 1.8;
}

.coming-soon-symbol {
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  width: 68px;
  height: 68px;
  border-radius: 22px;
  background: var(--color-brand-soft);
  color: var(--color-brand);
  font-size: 2.5rem;
  font-weight: 400;
}

/* Responsive layout */

@media (max-width: 700px) {
  .subjects-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .subject-card {
    gap: 14px;
    padding: 19px;
  }

  .subject-symbol {
    width: 46px;
    height: 46px;
    border-radius: 13px;
    font-size: 1.3rem;
  }

  .coming-soon-symbol {
    width: 52px;
    height: 52px;
    border-radius: 16px;
    font-size: 2rem;
  }
}

@media (max-width: 420px) {
  .subject-card {
    grid-template-columns: auto minmax(0, 1fr);
  }

  .subject-arrow {
    display: none;
  }

  .recent-subject-card {
    align-items: flex-start;
    gap: 13px;
    padding: 18px;
  }
}

/* ========================================
   CREATOR NOTE — NOVA ASTER
   ======================================== */

.creator-note {
  margin-top: 20px;
  margin-bottom: 48px;
}

.creator-note-content {
  max-width: 760px;
  padding: 26px 28px;
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
}

.creator-note-content .eyebrow {
  color: var(--color-text-muted);
  font-size: 0.7rem;
}

.creator-note-content h2 {
  margin: 8px 0 12px;
  font-size: clamp(1.4rem, 3vw, 1.8rem);
  letter-spacing: -0.03em;
}

.creator-note-content > p:not(.eyebrow) {
  max-width: 650px;
  color: var(--color-text-muted);
  font-size: 0.92rem;
  line-height: 1.8;
}

.creator-note-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 6px;
  color: var(--color-text);
  font-size: 0.9rem;
  font-weight: 650;
  text-decoration: underline;
  text-decoration-color: var(--color-border);
  text-underline-offset: 4px;
}

.creator-note-link:hover {
  color: var(--color-brand);
  text-decoration-color: currentColor;
}

/* ========================================
   MATHEMATICS LEARNING PAGE
   ======================================== */

.subject-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  align-items: center;
  gap: clamp(32px, 6vw, 80px);
  padding-top: clamp(54px, 9vw, 100px);
  padding-bottom: clamp(64px, 9vw, 110px);
}

.subject-hero-content {
  min-width: 0;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 38px;
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.92rem;
  transition: color var(--transition-fast);
}

.back-link:hover {
  color: var(--color-brand);
}

.subject-hero h1 {
  max-width: 720px;
  margin: 16px 0 22px;
  font-size: clamp(2.6rem, 5.5vw, 4.7rem);
  line-height: 1.06;
  letter-spacing: -0.055em;
}

.subject-hero-description {
  max-width: 590px;
  color: var(--color-text-muted);
  font-size: 1.06rem;
  line-height: 1.9;
}

.subject-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.eyebrow {
  margin: 0;
  color: var(--color-brand);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  line-height: 1.6;
  text-transform: uppercase;
}

.subject-hero-actions .button,
.visual-exploration .button,
.practice-panel .button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 19px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font: inherit;
  font-size: 0.91rem;
  font-weight: 700;
  text-decoration: none;
  transition:
    transform var(--transition-fast),
    background var(--transition-fast),
    border-color var(--transition-fast);
}

.button-primary {
  border-color: var(--color-brand) !important;
  background: var(--color-brand);
  color: #fff;
}

.button-secondary {
  background: var(--color-surface);
  color: var(--color-text);
}

.subject-hero-actions .button:hover,
.visual-exploration .button:hover,
.practice-panel .button:hover {
  transform: translateY(-2px);
}

.math-visual {
  position: relative;
  display: grid;
  place-items: center;
  width: 100%;
  max-width: 440px;
  aspect-ratio: 1;
  justify-self: end;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 36px;
  background:
    radial-gradient(
      circle at 50% 50%,
      var(--color-brand-soft),
      transparent 68%
    ),
    var(--color-surface);
}

.math-orbit {
  position: absolute;
  width: 76%;
  aspect-ratio: 1;
  border: 1px solid var(--color-brand);
  border-radius: 50%;
  opacity: 0.24;
}

.math-orbit-one {
  transform: scaleY(0.48) rotate(35deg);
}

.math-orbit-two {
  transform: scaleY(0.48) rotate(-35deg);
}

.math-center {
  display: grid;
  place-items: center;
  width: 100px;
  height: 100px;
  border: 1px solid var(--color-brand);
  border-radius: 30px;
  background: var(--color-surface);
  color: var(--color-brand);
  font-size: 4rem;
  box-shadow: var(--shadow-card);
  transform: rotate(-8deg);
}

.math-symbol,
.math-equation {
  position: absolute;
  color: var(--color-brand);
  font-weight: 750;
}

.math-symbol {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border: 1px solid var(--color-border);
  border-radius: 18px;
  background: var(--color-surface);
  font-size: 1.8rem;
  box-shadow: var(--shadow-card);
}

.math-symbol-one {
  top: 17%;
  left: 18%;
}

.math-symbol-two {
  top: 23%;
  right: 15%;
}

.math-symbol-three {
  right: 17%;
  bottom: 17%;
}

.math-equation {
  bottom: 20%;
  left: 14%;
  padding: 10px 13px;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  background: var(--color-surface);
  font-size: 1rem;
}

.subject-section {
  padding-top: 45px;
  padding-bottom: 65px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 30px;
}

.section-heading h2,
.visual-exploration h2,
.practice-panel h2 {
  margin: 10px 0 14px;
  font-size: clamp(1.8rem, 3.6vw, 2.7rem);
  line-height: 1.2;
  letter-spacing: -0.04em;
}

.section-heading p:not(.eyebrow),
.visual-exploration-copy > p:not(.eyebrow),
.practice-panel p:not(.eyebrow) {
  max-width: 650px;
  color: var(--color-text-muted);
  line-height: 1.85;
}

.section-index {
  flex-shrink: 0;
  padding-bottom: 8px;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
}

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

.learning-path-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
  min-height: 245px;
  padding: 25px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  color: var(--color-text);
  text-decoration: none;
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

.learning-path-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-brand);
  box-shadow: var(--shadow-card);
}

.path-number {
  position: absolute;
  top: 22px;
  right: 23px;
  color: var(--color-text-muted);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
}

.path-icon {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  margin-bottom: 22px;
  border-radius: 16px;
  background: var(--color-brand-soft);
  color: var(--color-brand);
  font-size: 1.6rem;
  font-weight: 750;
}

.learning-path-card h3 {
  margin: 0 0 10px;
  font-size: 1.12rem;
  line-height: 1.4;
}

.learning-path-card p {
  margin: 0 0 22px;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  line-height: 1.8;
}

.path-link {
  margin-top: auto;
  color: var(--color-brand);
  font-size: 0.86rem;
  font-weight: 750;
}

.visual-exploration {
  overflow: hidden;
  background: var(--color-surface-alt);
}

.visual-exploration-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 0.8fr);
  align-items: center;
  gap: 55px;
}

.visual-exploration-copy {
  padding: 25px 0;
}

.visual-formula {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 290px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 28px;
  background: var(--color-surface);
  color: var(--color-brand);
}

.visual-formula > span:first-child {
  position: absolute;
  top: 25px;
  left: 25px;
  font-size: 1.2rem;
  font-weight: 750;
}

.formula-axis {
  position: absolute;
  right: 25px;
  bottom: 25px;
  font-size: 0.9rem;
}

.formula-curve {
  font-size: 9rem;
  font-weight: 300;
  transform: rotate(180deg) scaleX(1.3);
}

.formula-point {
  position: absolute;
  top: 42%;
  left: 49%;
  font-size: 1.2rem;
}

.practice-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 35px;
  padding: clamp(25px, 5vw, 45px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-surface);
}

.practice-panel > div {
  max-width: 680px;
}

.practice-panel h2 {
  font-size: clamp(1.65rem, 3vw, 2.3rem);
}

.practice-panel p:last-child {
  margin-bottom: 0;
}

.site-footer {
  margin-top: 25px;
}

@media (max-width: 900px) {
  .subject-hero {
    grid-template-columns: minmax(0, 1fr) minmax(230px, 0.8fr);
    gap: 28px;
  }

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

  .visual-exploration-inner {
    gap: 30px;
  }
}

@media (max-width: 680px) {
  .subject-hero {
    grid-template-columns: 1fr;
    padding-top: 38px;
  }

  .back-link {
    margin-bottom: 28px;
  }

  .subject-hero h1 {
    font-size: clamp(2.5rem, 11vw, 3.8rem);
  }

  .math-visual {
    width: min(100%, 370px);
    justify-self: center;
    border-radius: 26px;
  }

  .section-heading {
    align-items: flex-start;
  }

  .learning-path-grid {
    grid-template-columns: 1fr;
  }

  .learning-path-card {
    min-height: 210px;
  }

  .visual-exploration-inner {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .visual-formula {
    min-height: 230px;
  }

  .practice-panel {
    align-items: flex-start;
    flex-direction: column;
    gap: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .learning-path-card,
  .math-symbol,
  .subject-hero-actions .button,
  .visual-exploration .button,
  .practice-panel .button {
    transition: none;
  }
}