/* ============================================================
   B3 Transformation — Base Stylesheet
   Clean, professional, mobile-responsive
   ============================================================ */

/* --- Reset & Base ----------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  color: #1a1a2e;
  background: #ffffff;
  line-height: 1.6;
}

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

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

/* --- Typography ------------------------------------------- */
h1 { font-size: 2.5rem; font-weight: 700; line-height: 1.2; }
h2 { font-size: 1.75rem; font-weight: 600; line-height: 1.3; }
h3 { font-size: 1.2rem;  font-weight: 600; line-height: 1.4; }
p  { font-size: 1rem;    color: #444460; }

/* --- Layout Utilities ------------------------------------- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
}

.section--alt {
  background: #f7f8fc;
}

/* --- Navigation ------------------------------------------- */
.nav {
  background: #0d1b2a;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.nav__brand {
  font-size: 1.2rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0.03em;
}

.nav__brand span {
  color: #4a9eff;
}

.nav__links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav__links a {
  color: #c8d6e5;
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: color 0.2s;
  padding-bottom: 2px;
  border-bottom: 2px solid transparent;
}

.nav__links a:hover {
  color: #ffffff;
}

.nav__links a.active {
  color: #ffffff;
  border-bottom-color: #4a9eff;
}

/* --- Hero ------------------------------------------------- */
.hero {
  background: linear-gradient(135deg, #0d1b2a 0%, #1a3a5c 100%);
  color: #ffffff;
  padding: 6rem 0 5rem;
  text-align: center;
}

.hero__eyebrow {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #4a9eff;
  margin-bottom: 1rem;
}

.hero__headline {
  font-size: 3rem;
  font-weight: 700;
  line-height: 1.15;
  max-width: 720px;
  margin: 0 auto 1.5rem;
}

.hero__sub {
  font-size: 1.15rem;
  color: #c8d6e5;
  max-width: 560px;
  margin: 0 auto 2.5rem;
  line-height: 1.7;
}

/* Sub-page hero (smaller) */
.hero--sub {
  padding: 4rem 0 3.5rem;
}

.hero--sub .hero__headline {
  font-size: 2.25rem;
}

/* --- Buttons ---------------------------------------------- */
.btn {
  display: inline-block;
  padding: 0.85rem 2rem;
  border-radius: 4px;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}

.btn:active {
  transform: translateY(1px);
}

.btn--primary {
  background: #4a9eff;
  color: #ffffff;
}

.btn--primary:hover {
  background: #2e88ef;
}

.btn--outline {
  background: transparent;
  color: #ffffff;
  border: 2px solid #4a9eff;
}

.btn--outline:hover {
  background: #4a9eff;
}

/* --- Intro Section ---------------------------------------- */
.intro {
  text-align: center;
  max-width: 720px;
  margin: 0 auto;
}

.intro h2 {
  margin-bottom: 1rem;
  color: #0d1b2a;
}

.intro p {
  font-size: 1.05rem;
  line-height: 1.75;
}

/* --- Cards Grid ------------------------------------------- */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  padding: 2rem;
  transition: box-shadow 0.2s;
}

.card:hover {
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

.card__icon {
  width: 44px;
  height: 44px;
  background: #eef4ff;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
  font-size: 1.3rem;
}

.card h3 {
  margin-bottom: 0.6rem;
  color: #0d1b2a;
}

/* --- CTA Section ------------------------------------------ */
.cta {
  text-align: center;
  background: #0d1b2a;
  color: #ffffff;
}

.cta h2 {
  margin-bottom: 1rem;
  color: #ffffff;
}

.cta p {
  color: #c8d6e5;
  max-width: 520px;
  margin: 0 auto 2rem;
  font-size: 1.05rem;
}

/* --- Footer ----------------------------------------------- */
.footer {
  background: #08111a;
  color: #6b7f90;
  text-align: center;
  padding: 2rem 1.5rem;
  font-size: 0.875rem;
}

.footer a {
  color: #4a9eff;
}

.footer a:hover {
  text-decoration: underline;
}

/* --- Section Heading helper ------------------------------- */
.section-heading {
  text-align: center;
  margin-bottom: 1rem;
  color: #0d1b2a;
}

.section-subhead {
  text-align: center;
  max-width: 580px;
  margin: 0 auto 3rem;
  color: #6b7f90;
  font-size: 1rem;
}

/* --- Audience badge (sub-pages) --------------------------- */
.audience-badge {
  display: inline-block;
  background: rgba(74,158,255,0.15);
  color: #4a9eff;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.3rem 0.8rem;
  border-radius: 20px;
  margin-bottom: 1rem;
}

/* --- Mobile ------------------------------------------------ */
@media (max-width: 768px) {
  h1                   { font-size: 2rem; }
  .hero__headline      { font-size: 2rem; }
  .hero--sub .hero__headline { font-size: 1.75rem; }
  h2                   { font-size: 1.5rem; }

  .nav__links {
    gap: 1.2rem;
  }

  .nav__links a {
    font-size: 0.82rem;
  }

  .section {
    padding: 3.5rem 0;
  }
}

@media (max-width: 540px) {
  .nav__inner {
    flex-direction: column;
    gap: 0.75rem;
    text-align: center;
  }

  .nav__links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem 1.2rem;
  }
}