.sv-header {
  position: sticky;
  top: 0;
  z-index: 40;
  width: 100%;
  backdrop-filter: blur(18px);
  background: linear-gradient(to bottom, rgba(5, 7, 8, 0.96), rgba(5, 7, 8, 0.88));
  border-bottom: 1px solid var(--color-border-subtle);
}

.sv-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-4);
  padding-bottom: var(--space-4);
  gap: var(--space-4);
}

.sv-brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}

.sv-brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 20%, rgba(16, 185, 129, 0.5), rgba(10, 35, 28, 0.9));
  border: 1px solid var(--color-border-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-serif);
  font-size: 0.95rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text);
}

.sv-brand-text {
  display: flex;
  flex-direction: column;
}

.sv-brand-title {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.sv-brand-subtitle {
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.sv-nav {
  display: flex;
  align-items: center;
}

.sv-nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.sv-nav-item {
  position: relative;
}

.sv-nav-link {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--color-text-muted);
  border: 1px solid transparent;
  transition: color var(--transition-medium), background-color var(--transition-medium), border-color var(--transition-medium), box-shadow var(--transition-medium), transform var(--transition-fast);
}

.sv-nav-link:hover,
.sv-nav-link:focus-visible {
  color: var(--color-text);
  background-color: rgba(16, 185, 129, 0.08);
  border-color: rgba(16, 185, 129, 0.4);
}

.sv-nav-highlight .sv-nav-link {
  color: #020617;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-soft));
  border-color: transparent;
  box-shadow: var(--shadow-subtle);
}

.sv-nav-highlight .sv-nav-link:hover,
.sv-nav-highlight .sv-nav-link:focus-visible {
  transform: translateY(-1px);
  box-shadow: var(--shadow-soft);
}

.sv-nav-toggle {
  display: none;
  position: relative;
  width: 42px;
  height: 36px;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--color-border-strong);
  background-color: rgba(5, 7, 8, 0.9);
  cursor: pointer;
}

.sv-nav-toggle-bar {
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background-color: var(--color-text);
  transition: transform var(--transition-medium), opacity var(--transition-medium), width var(--transition-medium);
}

.sv-nav-toggle[aria-expanded="true"] .sv-nav-toggle-bar:first-child {
  transform: translateY(3px) rotate(45deg);
}

.sv-nav-toggle[aria-expanded="true"] .sv-nav-toggle-bar:last-child {
  transform: translateY(-3px) rotate(-45deg);
  width: 18px;
}

@media (max-width: 900px) {
  .sv-nav-toggle {
    display: flex;
  }

  .sv-nav {
    position: fixed;
    inset: 60px 0 auto 0;
    z-index: 30;
    pointer-events: none;
  }

  .sv-nav-list {
    flex-direction: column;
    align-items: stretch;
    margin: 0 var(--space-4);
    padding: var(--space-4);
    background: radial-gradient(circle at top left, rgba(16, 185, 129, 0.16), transparent 55%),
      radial-gradient(circle at bottom right, rgba(15, 23, 42, 0.94), #020617);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-strong);
    box-shadow: var(--shadow-strong);
    transform-origin: top;
    transform: scaleY(0.8);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-medium), transform var(--transition-medium), visibility var(--transition-medium);
  }

  .sv-nav-link {
    width: 100%;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    font-size: 0.82rem;
  }

  .sv-nav-open .sv-nav-list {
    opacity: 1;
    width: 100%;
    visibility: visible;
    transform: scaleY(1);
    pointer-events: auto;
  }

  .sv-nav-open .sv-nav {
    pointer-events: auto;
  }
}

@media (max-width: 480px) {
  .sv-brand-subtitle {
    display: none;
  }
}