.header {
  position: sticky;
  top: 0;
  z-index: 100;
  width: 100%;
  height: var(--header-height); 
  background-color: var(--color-header-bg); 
  border-bottom: 1px solid var(--color-border); 
}

.header__container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  height: 100%;
  max-width: var(--header-content-max-w); 
  margin-inline: auto;
  padding-inline: var(--container-padding-x); 
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-8); 
  flex-shrink: 0;
}

.header__logo-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;    
  height: 2.5rem;   
  background-color: var(--color-primary);
  border-radius: var(--radius-xs); 
  flex-shrink: 0;
}

.header__logo-icon {
  height: 2.5rem;
  width: auto;
  display: block;
  flex-shrink: 0;
}

@media (max-width: 1120px) {
  .header__logo-icon {
    height: 2rem;
  }
}

.header__logo-text {
  font-family: var(--font-family-base);
  font-size: var(--font-size-logo);       
  font-weight: var(--font-weight-bold);   
  line-height: var(--line-height-logo);   
  color: var(--color-primary);
  letter-spacing: var(--letter-spacing-logo); 
  white-space: nowrap;
}

.header__nav {
  display: flex;
  align-items: center;
}

.header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--spacing-40); 
}

.header__nav-link {
  font-size: var(--font-size-nav);           
  font-weight: var(--font-weight-semibold);  
  line-height: var(--line-height-sm);        
  color: var(--color-heading);               
  white-space: nowrap;

  
  transition: opacity var(--transition-base);
}

.header__nav-link:hover {
  opacity: 0.7;
}

.header__nav-link--active {
  
}

.header__hamburger {
  display: none; 
  flex-direction: column;
  justify-content: center;
  gap: 0.3125rem; 
  width: 2rem;    
  height: 2rem;   
  padding: var(--spacing-4);
}

.header__hamburger-line {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-heading);
  border-radius: 1px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.header__hamburger[aria-expanded="true"] .header__hamburger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.header__hamburger[aria-expanded="true"] .header__hamburger-line:nth-child(2) {
  opacity: 0;
}

.header__hamburger[aria-expanded="true"] .header__hamburger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media (max-width: 1120px) {
  .header__hamburger {
    display: flex;
  }

  .header__nav {
    
    position: absolute;
    top: var(--header-height); 
    left: 0;
    right: 0;
    z-index: 99;
    background-color: var(--color-header-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-24);

    
    opacity: 0;
    pointer-events: none;
    transform: translateY(-0.5rem);
    transition:
      opacity var(--transition-base),
      transform var(--transition-base);
  }

  
  .header__nav.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .header__nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-24);
  }
}

@media (prefers-reduced-motion: reduce) {
  .header__nav {
    transition: none;
  }

  .header__hamburger-line {
    transition: none;
  }
}