.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 26px;
  border: 1px solid var(--line);
  background: rgba(23, 22, 15, 0.55);
  backdrop-filter: blur(10px);
  transition: background .3s var(--ease), border-color .3s var(--ease);
}
.site-header.is-scrolled {
  background: rgba(23, 22, 15, 0.92);
  border-color: rgba(255, 176, 32, .3);
}

.brand { display: inline-flex; align-items: center; gap: 10px; font-family: var(--mono-display); font-weight: 700; letter-spacing: -0.01em; font-size: 16px; color: var(--text); }
.brand-mark {
  display: block;
  width: 84px;
  height: 84px;
  border-radius: 18px;
  transition: transform .3s var(--ease), box-shadow .3s var(--ease);
}
.brand:hover .brand-mark { transform: rotate(-8deg) scale(1.08); box-shadow: 0 0 16px rgba(255, 176, 32, .35); }

/* Shared underline-on-hover treatment for header and footer nav links */
.desktop-nav { display: flex; align-items: center; gap: 28px; color: var(--muted); font-size: 13px; font-weight: 500; }
.desktop-nav a, .site-footer nav a {
  position: relative;
  padding-bottom: 3px;
  transition: color .2s ease;
}
.desktop-nav a::after, .site-footer nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1.5px;
  background: var(--amber);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform .25s var(--ease);
}
.desktop-nav a:hover, .site-footer nav a:hover { color: var(--amber); }
.desktop-nav a:hover::after, .site-footer nav a:hover::after { transform: scaleX(1); transform-origin: left; }

.header-actions { display: flex; align-items: center; gap: 10px; }
.header-cta {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  align-items: center;
  padding: 10px 16px;
  border: 1px solid var(--amber);
  color: var(--amber);
  font-size: 13px;
  font-weight: 700;
  transition: background .2s ease, color .2s ease;
}
.header-cta::before {
  content: "";
  position: absolute;
  top: 0;
  left: -75%;
  width: 45%;
  height: 100%;
  background: linear-gradient(115deg, transparent, rgba(255, 255, 255, .5), transparent);
  transform: skewX(-20deg);
  transition: left .55s var(--ease);
  pointer-events: none;
}
.header-cta:hover::before { left: 125%; }
.header-cta:hover { background: var(--amber); color: #12100b; }

.nav-toggle {
  display: none;
  position: relative;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  padding: 0;
}
.nav-toggle span {
  position: absolute;
  left: 11px;
  width: 18px;
  height: 2px;
  background: var(--text);
  transition: transform .3s var(--ease), opacity .2s ease, top .3s var(--ease);
}
.nav-toggle span:nth-child(1) { top: 14px; }
.nav-toggle span:nth-child(2) { top: 19px; }
.nav-toggle span:nth-child(3) { top: 24px; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { top: 19px; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { top: 19px; transform: rotate(-45deg); }

.mobile-nav {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  flex-direction: column;
  gap: 2px;
  padding: 10px;
  border: 1px solid var(--line);
  border-top: none;
  background: rgba(23, 22, 15, 0.98);
  opacity: 0;
  transform: translateY(-6px);
  pointer-events: none;
  transition: opacity .2s var(--ease), transform .2s var(--ease);
}
.mobile-nav.is-open { opacity: 1; transform: translateY(0); pointer-events: auto; }
.mobile-nav a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 13px 12px;
  color: var(--muted);
  font-weight: 500;
  font-size: 14px;
  border-bottom: 1px dashed var(--line-soft);
  transition: color .2s ease, background .2s ease;
}
.mobile-nav a::after {
  content: "";
  width: 6px;
  height: 6px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(-45deg);
  opacity: .5;
  transition: transform .2s ease;
}
.mobile-nav a:hover { color: var(--amber); background: rgba(255,176,32,.05); }
.mobile-nav a:hover::after { transform: rotate(-45deg) translate(2px, -2px); }
.mobile-nav .btn { margin-top: 8px; border-bottom: none; justify-content: center; }
.mobile-nav .btn::after { content: none; }