.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 76px;
  padding: 14px clamp(18px, 4vw, 52px);
  color: var(--white);
  background: rgba(16, 24, 32, 0.97);
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(18px);
  transition: box-shadow 180ms ease, background 180ms ease;
}

.site-header.is-scrolled {
  background: #101820;
  box-shadow: 0 12px 35px rgba(0, 0, 0, 0.22);
}

.brand img {
  width: clamp(180px, 20vw, 250px);
  height: auto;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 30px);
  font-size: 0.95rem;
  font-weight: 700;
}

.main-nav a {
  position: relative;
  text-decoration: none;
}

.main-nav a::after {
  position: absolute;
  right: 0;
  bottom: -8px;
  left: 0;
  height: 2px;
  content: "";
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.main-nav a:hover::after,
.main-nav a:focus-visible::after,
.main-nav a[aria-current="page"]::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  border: 1px solid rgba(255, 255, 255, 0.42);
  background: transparent;
  border-radius: var(--radius);
}

.nav-toggle span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--white);
}

.section,
.section-grid,
.feature-section,
.contact-section {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  padding: clamp(48px, 6vw, 72px) 0;
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.78fr) minmax(0, 1fr);
  gap: clamp(28px, 6vw, 80px);
  align-items: start;
}

.intro {
  padding-top: clamp(42px, 5vw, 60px);
}

.section-heading {
  max-width: 820px;
  margin-bottom: 34px;
}

.feature-section {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(0, 1fr);
  gap: clamp(30px, 6vw, 78px);
  align-items: center;
}

.muted-band {
  width: 100%;
  max-width: none;
  padding-right: max(20px, calc((100vw - var(--max)) / 2));
  padding-left: max(20px, calc((100vw - var(--max)) / 2));
  background: var(--soft);
}

.contact-section {
  border-top: 1px solid var(--line);
}

.site-footer {
  display: grid;
  gap: 22px;
  justify-items: center;
  padding: 44px 20px;
  color: rgba(255, 255, 255, 0.78);
  background: #111820;
  text-align: center;
}

.site-footer img {
  width: min(260px, 70vw);
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 18px;
}

.site-footer a {
  color: var(--white);
  text-decoration: none;
}

.site-footer p {
  margin: 0;
  font-size: 0.9rem;
}

@media (max-width: 880px) {
  .nav-toggle {
    display: block;
  }

  .main-nav {
    position: fixed;
    top: 76px;
    right: 14px;
    left: 14px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 18px;
    border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: var(--radius);
    background: var(--ink);
    box-shadow: 0 18px 55px rgba(0, 0, 0, 0.3);
  }

  .main-nav.is-open {
    display: flex;
  }

  .main-nav a {
    padding: 10px 4px;
  }

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

@media (max-width: 560px) {
  .site-header {
    min-height: 68px;
  }

  .brand img {
    width: 180px;
  }

  .main-nav {
    top: 68px;
  }
}