:root {
  --brand-green: #1c3d2e;
  --brand-blue: #2a4d69;
  --ink-900: #1f2933;
  --ink-700: #38424d;
  --surface-0: #ffffff;
  --surface-50: #f8f8f6;
  --line-soft: #d9e0e6;
}

header {
  position: fixed;
  top: 36px;
  left: 0;
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 42px;
  background-color: rgba(250, 249, 246, 0.96);
  border-bottom: 1px solid var(--line-soft);
  backdrop-filter: blur(6px);
  transition: padding 0.25s ease, box-shadow 0.25s ease;
  z-index: 1500;
}

header.shrink {
  padding: 11px 34px;
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.08);
}

.top-bar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: var(--brand-green);
  color: #edf1f4;
  padding: 9px 20px;
  text-align: left;
  font-size: 12px;
  z-index: 1600;
  letter-spacing: 0.35px;
}

.logo {
  height: 68px;
  transition: height 0.25s ease;
}

header.shrink .logo {
  height: 48px;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 28px;
  margin: 0;
  padding: 0;
}

.nav-links li {
  display: inline-flex;
}

.nav-links a {
  text-decoration: none;
  color: var(--ink-700);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  position: relative;
  transition: color 0.25s ease;
}

.nav-links a::after {
  content: "";
  position: absolute;
  width: 0;
  height: 2px;
  left: 0;
  bottom: -7px;
  background: var(--brand-blue);
  transition: width 0.25s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--brand-blue);
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
  width: 100%;
}

.burger {
  position: relative;
  width: 36px;
  height: 26px;
  background: transparent;
  cursor: pointer;
  display: none;
  z-index: 2200;
}

.burger input {
  display: none;
}

.burger span {
  display: block;
  position: absolute;
  height: 3px;
  width: 100%;
  background: var(--brand-green);
  opacity: 1;
  left: 0;
  transform: rotate(0deg);
  transition: 0.22s ease-in-out;
}

.burger span:nth-of-type(1) {
  top: 0;
  transform-origin: left center;
}

.burger span:nth-of-type(2) {
  top: 50%;
  transform: translateY(-50%);
  transform-origin: left center;
}

.burger span:nth-of-type(3) {
  top: 100%;
  transform: translateY(-100%);
  transform-origin: left center;
}

.burger input:checked ~ span:nth-of-type(1) {
  transform: rotate(45deg);
  top: 0;
  left: 4px;
}

.burger input:checked ~ span:nth-of-type(2) {
  width: 0;
  opacity: 0;
}

.burger input:checked ~ span:nth-of-type(3) {
  transform: rotate(-45deg);
  top: 25px;
  left: 4px;
}

.overlay-menu {
  display: flex;
  position: fixed;
  inset: 0;
  background: rgba(255, 255, 255, 0.98);
  z-index: 2000;
  padding: 20px;
  box-sizing: border-box;
  overflow: hidden;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.overlay-menu.show-overlay-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.overlay-menu ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.overlay-menu ul li a {
  text-decoration: none;
  color: var(--ink-900);
  font-size: clamp(28px, 8vw, 42px);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: color 0.25s ease;
}

.overlay-menu ul li a:hover,
.overlay-menu ul li a:focus-visible {
  color: var(--brand-blue);
}

@media (max-width: 900px) {
  header {
    top: 34px;
    padding: 14px 18px;
  }

  header.shrink {
    padding: 10px 16px;
  }

  .logo {
    height: 52px;
  }

  header.shrink .logo {
    height: 42px;
  }

  .burger {
    display: block;
    margin-left: auto;
  }

  .nav-links {
    display: none;
  }
}

@media (max-width: 560px) {
  .top-bar {
    padding: 7px 12px;
    font-size: 11px;
  }

  header {
    top: 30px;
    padding: 12px 12px;
  }

  header.shrink {
    padding: 9px 12px;
  }

  .logo {
    height: 46px;
  }

  header.shrink .logo {
    height: 40px;
  }
}

@media (min-width: 901px) {
  .burger {
    display: none;
  }

  .overlay-menu {
    display: none;
  }
}

.no-scroll {
  overflow: hidden;
}