/* =========================================================
   ThinkNest — Stylesheet
   Palette derived from the ThinkNest mark:
     ink   #0A1B38  (deep navy — "think", nest linework)
     blue  #2235D6  (royal blue — "Nest", CTAs, links)
     amber #E8A24C  (egg amber — highlights, numerals)
   ========================================================= */

:root {
  --ink: #0A1B38;
  --ink-soft: #4B5568;
  --ink-faint: #8A93A3;
  --blue: #2235D6;
  --blue-deep: #1a29ad;
  --amber: #E8A24C;
  --paper: #FFFFFF;
  --paper-warm: #FAF9F5;
  --line: #E6E2D9;
  --line-strong: #D8D3C6;

  --font-display: 'Space Grotesk', 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;

  --container: 1240px;
  --gutter: clamp(20px, 5vw, 64px);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* ---------- Typography ---------- */

.font-display { font-family: var(--font-display); }

.eyebrow {
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--blue);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.eyebrow::before {
  content: '';
  width: 16px;
  height: 1.5px;
  background: var(--amber);
  display: inline-block;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--ink);
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 0;
}

.section-heading {
  font-size: clamp(1.75rem, 3.4vw, 2.6rem);
  font-weight: 600;
  max-width: 720px;
}

.body-text {
  color: var(--ink-soft);
  line-height: 1.65;
  font-size: 1rem;
}

.mark-underline {
  position: relative;
  white-space: nowrap;
}
.mark-underline svg {
  position: absolute;
  left: 0;
  bottom: -0.08em;
  width: 100%;
  height: 0.3em;
  overflow: visible;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0.85rem 1.6rem;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.92rem;
  border-radius: 3px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.25s ease, background 0.25s ease, border-color 0.25s ease, color 0.25s ease;
  white-space: nowrap;
}

.btn-primary {
  background: var(--ink);
  color: var(--paper);
}
.btn-primary:hover {
  background: var(--blue);
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-strong);
}
.btn-outline:hover {
  border-color: var(--ink);
  transform: translateY(-1px);
}

.btn-sm {
  padding: 0.6rem 1.1rem;
  font-size: 0.82rem;
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 4px 24px rgba(10, 27, 56, 0.045);
}

.nav-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 78px;
}

.logo-link { display: flex; align-items: center; }
.logo-full { height: 34px; width: auto; }
.logo-mark { height: 34px; width: auto; display: none; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.4rem;
}

.nav-links a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--ink-soft);
  position: relative;
  padding: 4px 0;
  transition: color 0.2s ease;
}

.nav-links a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 1.5px;
  background: var(--amber);
  transition: width 0.25s ease;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--ink);
}
.nav-links a:hover::after,
.nav-links a.is-active::after {
  width: 100%;
}

.header-right { display: flex; align-items: center; gap: 1.5rem; }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  color: var(--ink);
}

.mobile-nav {
  position: fixed;
  inset: 78px 0 0 0;
  background: var(--paper);
  transform: translateY(-8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s;
  z-index: 99;
  overflow-y: auto;
}
.mobile-nav.is-open {
  opacity: 1;
  transform: translateY(0);
  visibility: visible;
}
.mobile-nav .container {
  padding-top: 2.5rem;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.mobile-nav a {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 500;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
}
.mobile-nav a.btn {
  margin-top: 2rem;
  align-self: flex-start;
  font-family: var(--font-body);
  font-size: 0.92rem;
  color: var(--paper);
  border-bottom: none;
  padding: 0.85rem 1.6rem;
}
.mobile-nav a.btn:hover { color: var(--paper); }

@media (max-width: 860px) {
  .nav-links, .header-right .btn-outline-desktop { display: none; }
  .nav-toggle { display: inline-flex; }
}

@media (max-width: 380px) {
  .logo-full { display: none; }
  .logo-mark { display: block; }
}

/* ---------- Hero ---------- */

.hero {
  position: relative;
  padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(3rem, 6vw, 5rem);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: end;
}

.hero-eyebrow-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 1.6rem;
}

.hero h1 {
  font-size: clamp(2.3rem, 5.2vw, 4rem);
  font-weight: 600;
  max-width: 15ch;
}

.hero-lede {
  margin-top: 1.6rem;
  max-width: 46ch;
  font-size: 1.08rem;
  color: var(--ink-soft);
  line-height: 1.7;
}

.hero-ctas {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  margin-top: 2.4rem;
  flex-wrap: wrap;
}

.hero-credibility {
  margin-top: 2.6rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--ink-faint);
  max-width: 40ch;
}

.hero-quote-card {
  border-left: 2px solid var(--amber);
  padding-left: 1.4rem;
  align-self: end;
}

.hero-quote-card p {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--ink);
}

.hero-quote-card span {
  display: block;
  margin-top: 0.9rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

.hero-stroke {
  position: absolute;
  right: -60px;
  top: 40px;
  width: 260px;
  opacity: 0.55;
  pointer-events: none;
}

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-quote-card { border-left: none; border-top: 2px solid var(--amber); padding-left: 0; padding-top: 1.2rem; margin-top: 1rem; }
  .hero-stroke { display: none; }
}

/* ---------- Reveal-on-scroll ---------- */

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Impact strip ---------- */

.impact {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: clamp(2.4rem, 5vw, 3.4rem) 0;
}

.impact-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(2rem, 6vw, 4.5rem);
  align-items: center;
}

.impact-number {
  font-family: var(--font-display);
  font-size: clamp(3.4rem, 8vw, 5.4rem);
  font-weight: 600;
  color: var(--ink);
  line-height: 1;
  white-space: nowrap;
}

.impact-number span { color: var(--amber); }

.impact-number-label {
  margin-top: 0.5rem;
  font-size: 0.85rem;
  color: var(--ink-faint);
  letter-spacing: 0.04em;
}

.impact-points {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  border-left: 1px solid var(--line);
  padding-left: clamp(2rem, 5vw, 3.5rem);
}

.impact-point {
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 500;
  color: var(--ink);
}

.impact-point small {
  display: block;
  margin-top: 0.4rem;
  font-family: var(--font-body);
  font-size: 0.84rem;
  font-weight: 400;
  color: var(--ink-faint);
}

@media (max-width: 860px) {
  .impact-row { grid-template-columns: 1fr; }
  .impact-points { border-left: none; padding-left: 0; grid-template-columns: 1fr; border-top: 1px solid var(--line); padding-top: 1.6rem; }
}

/* ---------- Section shell ---------- */

.section { padding: clamp(4rem, 8vw, 7rem) 0; }
.section-alt { background: var(--paper-warm); }

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 2rem;
  margin-bottom: clamp(2.4rem, 5vw, 3.6rem);
}

.section-head .body-text { max-width: 380px; }

@media (max-width: 760px) {
  .section-head { flex-direction: column; align-items: flex-start; gap: 1rem; }
}

/* ---------- Use cases (timeline) ---------- */

.usecase-list { border-top: 1px solid var(--line); }

.usecase-item {
  display: grid;
  grid-template-columns: 90px 1fr 1fr;
  gap: 2rem;
  align-items: baseline;
  padding: 1.9rem 0;
  border-bottom: 1px solid var(--line);
  transition: background 0.3s ease;
}

.usecase-item:hover { background: rgba(34, 53, 214, 0.025); }

.usecase-num {
  font-family: var(--font-display);
  font-size: 1rem;
  color: var(--amber);
  font-weight: 600;
}

.usecase-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
}

.usecase-desc {
  color: var(--ink-soft);
  font-size: 0.96rem;
  line-height: 1.6;
}

@media (max-width: 720px) {
  .usecase-item { grid-template-columns: 1fr; gap: 0.5rem; }
  .usecase-num { order: 1; }
  .usecase-title { order: 2; }
  .usecase-desc { order: 3; margin-top: 0.3rem; }
}

/* ---------- School programs (index list) ---------- */

.program-index { border-top: 1px solid var(--line); }

.program-row {
  display: grid;
  grid-template-columns: 44px 1fr 2fr;
  gap: 1.8rem;
  align-items: flex-start;
  padding: 1.7rem 0;
  border-bottom: 1px solid var(--line);
  position: relative;
}

.program-row .program-tag {
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--ink-faint);
  padding-top: 0.2rem;
}

.program-row h4 {
  font-size: 1.08rem;
  font-weight: 600;
  letter-spacing: -0.005em;
}

.program-row p {
  color: var(--ink-soft);
  font-size: 0.94rem;
  line-height: 1.6;
  max-width: 46ch;
}

.program-row::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--amber);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 0.35s ease;
}
.program-row:hover::before { transform: scaleY(1); }

@media (max-width: 700px) {
  .program-row { grid-template-columns: 32px 1fr; }
  .program-row p { grid-column: 2 / 3; }
}

/* ---------- College programs ---------- */

.college-tracks {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.track-card {
  background: var(--paper);
  padding: 2rem 1.8rem;
  transition: background 0.3s ease;
}
.track-card:hover { background: var(--paper-warm); }

.track-index {
  font-family: var(--font-display);
  font-size: 0.78rem;
  color: var(--blue);
  font-weight: 600;
  letter-spacing: 0.06em;
}

.track-card h4 {
  margin-top: 0.9rem;
  font-size: 1.15rem;
  font-weight: 600;
}

.track-card p {
  margin-top: 0.7rem;
  color: var(--ink-soft);
  font-size: 0.92rem;
  line-height: 1.6;
}

@media (max-width: 820px) {
  .college-tracks { grid-template-columns: 1fr; }
}

.model-strip {
  margin-top: 2.6rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 0.9rem;
}

.model-chip {
  font-size: 0.82rem;
  color: var(--ink-soft);
  padding: 0.5rem 0.95rem;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  white-space: nowrap;
}

.model-chip strong { color: var(--ink); font-weight: 600; }

/* ---------- Our approach (process rail) ---------- */

.approach-rail {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  position: relative;
  margin-top: 1rem;
}

.approach-rail::before {
  content: '';
  position: absolute;
  top: 11px;
  left: 4%;
  right: 4%;
  height: 1px;
  background: var(--line-strong);
}

.approach-step {
  position: relative;
  padding-top: 2.6rem;
  padding-right: 1.2rem;
}

.approach-dot {
  position: absolute;
  top: 0;
  left: 0;
  width: 23px;
  height: 23px;
  border-radius: 50%;
  background: var(--paper);
  border: 1.5px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--ink);
  transition: background 0.35s ease, color 0.35s ease, border-color 0.35s ease, transform 0.35s ease;
}

.approach-step.is-active .approach-dot,
.approach-step:hover .approach-dot {
  background: var(--amber);
  border-color: var(--amber);
  color: var(--ink);
  transform: scale(1.12);
}

.approach-step h4 {
  font-size: 1.1rem;
  font-weight: 600;
}

.approach-step p {
  margin-top: 0.5rem;
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.55;
}

@media (max-width: 860px) {
  .approach-rail { grid-template-columns: 1fr; gap: 1.8rem; }
  .approach-rail::before { top: 0; bottom: 0; left: 11px; right: auto; width: 1px; height: auto; }
  .approach-step { padding-top: 0; padding-left: 2.6rem; padding-right: 0; }
  .approach-dot { top: 2px; left: 0; }
}

/* ---------- Program categories (institutions) ---------- */

.category-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(2rem, 5vw, 5rem);
}

.category-col h4 {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--blue);
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}

.category-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.category-col li {
  padding: 0.95rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.98rem;
  color: var(--ink);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.category-col li::after {
  content: '→';
  color: var(--amber);
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.category-col li:hover::after { opacity: 1; transform: translateX(0); }

@media (max-width: 700px) {
  .category-cols { grid-template-columns: 1fr; gap: 2.5rem; }
}

/* ---------- Why ThinkNest ---------- */

.why-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2.2rem;
}

.why-item { padding-top: 1.4rem; border-top: 2px solid var(--ink); }

.why-item h4 {
  font-size: 1.02rem;
  font-weight: 600;
}

.why-item p {
  margin-top: 0.6rem;
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.6;
}

@media (max-width: 860px) {
  .why-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 540px) {
  .why-grid { grid-template-columns: 1fr; }
}

/* ---------- Final CTA ---------- */

.final-cta {
  border-top: 1px solid var(--line);
  padding: clamp(4rem, 9vw, 7rem) 0;
}

.cta-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 3rem;
  align-items: center;
}

.final-cta h2 {
  font-size: clamp(1.9rem, 4vw, 2.9rem);
  font-weight: 600;
  max-width: 14ch;
}

.final-cta-actions {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1.1rem;
}

@media (max-width: 820px) {
  .cta-grid { grid-template-columns: 1fr; }
  .final-cta-actions { align-items: stretch; }
  .final-cta-actions .btn { justify-content: center; }
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--line);
  padding: clamp(3rem, 6vw, 4rem) 0 2rem;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem;
  padding-bottom: 2.6rem;
}

.footer-brand .logo-full { height: 30px; margin-bottom: 1rem; }
.footer-brand p {
  color: var(--ink-faint);
  font-size: 0.9rem;
  max-width: 32ch;
  line-height: 1.6;
}

.footer-col h5 {
  font-family: var(--font-body);
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 1rem;
}

.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin-bottom: 0.7rem; }
.footer-col a {
  font-size: 0.92rem;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}
.footer-col a:hover { color: var(--blue); }

.footer-bottom {
  padding-top: 1.8rem;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--ink-faint);
}

.footer-socials { display: flex; gap: 1.2rem; }
.footer-socials a { color: var(--ink-faint); transition: color 0.2s ease; }
.footer-socials a:hover { color: var(--blue); }

@media (max-width: 760px) {
  .footer-top { grid-template-columns: 1fr; gap: 2rem; }
}

/* ---------- Focus states ---------- */

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
  border-radius: 2px;
}