:root {
  --bg: #f6f7f2;
  --surface: #ffffff;
  --surface-strong: #edf3f0;
  --ink: #132127;
  --muted: #5d686c;
  --line: #d8dfda;
  --blue: #164e78;
  --teal: #176d71;
  --violet: #5c4d8b;
  --gold: #b66a2b;
  --shadow: 0 24px 60px rgba(19, 33, 39, 0.09);
  --max: 1160px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    linear-gradient(180deg, rgba(237, 243, 240, 0.9), rgba(246, 247, 242, 0) 560px),
    var(--bg);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

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

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

p {
  color: var(--muted);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: min(var(--max), calc(100% - 32px));
  margin: 16px auto 0;
  padding: 12px 14px;
  border: 1px solid rgba(216, 223, 218, 0.9);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 14px 44px rgba(19, 33, 39, 0.08);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 850;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 7px;
  background: var(--ink);
  color: #fff;
  font-size: 0.78rem;
}

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

.site-nav a {
  padding: 9px 12px;
  border-radius: 6px;
  color: var(--muted);
  font-size: 0.94rem;
  font-weight: 700;
}

.site-nav a:hover {
  background: var(--surface-strong);
  color: var(--ink);
}

.site-nav .nav-cta {
  background: var(--blue);
  color: #fff;
}

.site-nav .nav-cta:hover {
  background: #0f3d61;
  color: #fff;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--surface);
}

.nav-toggle span:not(.sr-only) {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  background: var(--ink);
}

.hero,
.section,
.site-footer {
  width: min(var(--max), calc(100% - 32px));
  margin-inline: auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(420px, 0.98fr);
  align-items: center;
  gap: 44px;
  min-height: calc(100vh - 124px);
  padding: 84px 0 58px;
}

.eyebrow {
  margin-bottom: 12px;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 850;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1 {
  max-width: 850px;
  margin-bottom: 22px;
  color: var(--ink);
  font-size: clamp(2.65rem, 6vw, 5.5rem);
  line-height: 0.97;
  letter-spacing: 0;
}

h2 {
  max-width: 780px;
  margin-bottom: 16px;
  color: var(--ink);
  font-size: clamp(1.9rem, 3vw, 3rem);
  line-height: 1.08;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  color: var(--ink);
  font-size: 1.07rem;
  line-height: 1.25;
}

.hero-text {
  max-width: 720px;
  font-size: clamp(1.04rem, 1.8vw, 1.25rem);
}

.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: 12px 18px;
  border: 1px solid transparent;
  border-radius: 7px;
  font-weight: 800;
  line-height: 1.2;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
}

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

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

.button.primary:hover {
  background: #0f3d61;
}

.button.primary.alt {
  background: var(--teal);
}

.button.primary.alt:hover {
  background: #10575a;
}

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

.button.secondary:hover {
  border-color: #b9c5c0;
}

.learning-map {
  min-width: 0;
}

.map-panel {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  min-height: 560px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background:
    linear-gradient(rgba(22, 78, 120, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(22, 78, 120, 0.06) 1px, transparent 1px),
    var(--surface);
  background-size: 28px 28px;
  box-shadow: var(--shadow);
}

.map-panel::before {
  content: "";
  position: absolute;
  inset: 46px;
  border: 2px solid rgba(92, 77, 139, 0.18);
  border-radius: 46%;
  transform: rotate(-10deg);
}

.map-node {
  position: relative;
  z-index: 1;
  display: flex;
  min-height: 122px;
  flex-direction: column;
  justify-content: space-between;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 12px 36px rgba(19, 33, 39, 0.08);
}

.map-node span,
.feature-card span,
.icap-grid span,
.contact-card span {
  color: var(--violet);
  font-size: 0.76rem;
  font-weight: 850;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.map-node strong {
  max-width: 180px;
  color: var(--ink);
  font-size: 1.06rem;
  line-height: 1.25;
}

.map-node.recommend {
  grid-column: span 2;
  margin-inline: 72px;
  border-color: rgba(22, 78, 120, 0.36);
  background: #f7fbfb;
}

.map-node.tutor {
  border-top: 4px solid var(--gold);
}

.map-node.path {
  border-top: 4px solid var(--teal);
}

.section {
  padding: 72px 0;
}

.section + .section {
  border-top: 1px solid rgba(216, 223, 218, 0.78);
}

.intro-strip {
  padding: 30px 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 14px 34px rgba(19, 33, 39, 0.06);
}

.intro-strip p {
  max-width: 930px;
  margin: 0;
  color: var(--ink);
  font-size: 1.05rem;
}

.intro-strip a {
  color: var(--blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.split {
  display: grid;
  grid-template-columns: 0.95fr 1.05fr;
  gap: 56px;
}

.copy-stack p {
  font-size: 1.04rem;
}

.emphasis {
  padding-left: 18px;
  border-left: 4px solid var(--teal);
  color: var(--ink);
  font-weight: 750;
}

.section-heading {
  max-width: 820px;
  margin-bottom: 32px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.feature-card,
.contact-card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 14px 34px rgba(19, 33, 39, 0.06);
}

.feature-card span {
  display: inline-block;
  margin-bottom: 22px;
}

.feature-card p,
.icap-grid p,
.contact-card p {
  margin-bottom: 0;
}

.band {
  width: 100%;
  max-width: none;
  padding-inline: max(16px, calc((100% - var(--max)) / 2));
  background: #eaf0ee;
}

.icap-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.icap-grid article {
  padding-top: 18px;
  border-top: 3px solid var(--violet);
}

.icap-grid span {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 16px;
  border-radius: 7px;
  background: var(--ink);
  color: #fff;
  font-size: 1rem;
}

.check-list {
  display: grid;
  gap: 10px;
  padding: 0;
  margin: 24px 0 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding-left: 22px;
  color: var(--ink);
  font-weight: 700;
}

.check-list li::before {
  content: "";
  position: absolute;
  top: 0.67em;
  left: 0;
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: var(--teal);
}

.demo-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 36px;
  padding: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--ink);
  box-shadow: var(--shadow);
}

.demo-panel h2,
.demo-panel p {
  color: #fff;
}

.demo-panel p:not(.eyebrow) {
  max-width: 680px;
  color: rgba(255, 255, 255, 0.78);
}

.demo-panel .button {
  background: #f4f7f5;
  color: var(--ink);
}

.demo-panel .button.primary {
  background: #f4f7f5;
  color: var(--ink);
}

.demo-panel .button.inverse {
  border-color: rgba(255, 255, 255, 0.28);
  background: transparent;
  color: #fff;
}

.demo-actions {
  display: flex;
  flex: 0 0 auto;
  flex-wrap: wrap;
  gap: 10px;
}

.contact-section {
  display: grid;
  grid-template-columns: 1fr 0.75fr;
  gap: 24px;
  align-items: start;
}

.contact-card a {
  display: block;
  margin: 8px 0 18px;
  color: var(--blue);
  font-size: 1.35rem;
  font-weight: 850;
  line-height: 1.2;
  word-break: break-word;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 30px 0 46px;
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: var(--ink);
  font-weight: 800;
}

@media (max-width: 980px) {
  .hero,
  .split,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding-top: 62px;
  }

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

@media (max-width: 760px) {
  .site-header {
    align-items: flex-start;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
    box-shadow: var(--shadow);
  }

  .site-header.nav-open .site-nav {
    display: flex;
  }

  h1 {
    font-size: clamp(2.45rem, 14vw, 4.25rem);
  }

  .map-panel {
    grid-template-columns: 1fr;
    min-height: auto;
    padding: 18px;
  }

  .map-panel::before {
    display: none;
  }

  .map-node.recommend {
    grid-column: auto;
    margin-inline: 0;
  }

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

  .demo-panel {
    display: grid;
    padding: 28px;
  }

  .site-footer {
    display: grid;
  }
}