/* Site header — thin editorial masthead that condenses on scroll */

.masthead {
  position: sticky;
  top: 0;
  z-index: 50;
  isolation: isolate;
  background: color-mix(in oklch, var(--color-paper) 82%, transparent);
  backdrop-filter: blur(14px) saturate(1.2);
  border-block-end: 1px solid transparent;
  transition: border-color var(--duration-normal) var(--ease-soft),
    background-color var(--duration-normal) var(--ease-soft);
}

.masthead.is-stuck {
  border-block-end-color: var(--rule);
  background: color-mix(in oklch, var(--color-paper) 94%, transparent);
}

.masthead__inner {
  /* Контент шапки поверх улитки: она проползает под названиями пунктов */
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2xs) var(--space-m);
  /* На мобильном строк две, поэтому шапка дышит меньше: рост зон нажатия
     компенсируем уменьшением собственных отступов. */
  padding-block: var(--space-2xs);
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  gap: 0.6ch;
  font-family: var(--font-display);
  font-size: 1.4rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand__logo {
  width: clamp(1.75rem, 1.4rem + 1vw, 2.25rem);
  height: auto;
  border-radius: 50%;
  margin-inline-end: 0.2ch;
  box-shadow: 0 0 0 1px color-mix(in oklch, var(--color-clay) 30%, transparent);
  transition: transform var(--duration-normal) var(--ease-out-expo);
}

.brand:hover .brand__logo,
.brand:focus-visible .brand__logo {
  transform: rotate(-8deg) scale(1.06);
}

.brand__mark {
  font-style: italic;
  color: var(--color-pine);
}

.brand__tag {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-muted);
}

/* Under 56rem the nav drops to its own scrollable row instead of a hamburger:
   four short links fit, and no JS is needed to open anything. */
.nav {
  order: 3;
  width: 100%;
  overflow-x: auto;
  scrollbar-width: none;
  border-block-start: 1px solid var(--rule);
}

.nav::-webkit-scrollbar {
  display: none;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 0.4rem + 1.6vw, 2.25rem);
}

.nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: var(--text-sm);
  font-weight: 500;
  text-decoration: none;
  color: var(--color-ink-soft);
  transition: color var(--duration-fast) var(--ease-soft);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: calc(50% - 1.05em);
  width: 100%;
  height: 1px;
  background: var(--color-clay);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--duration-normal) var(--ease-out-expo);
}

.nav__link:hover,
.nav__link:focus-visible {
  color: var(--color-ink);
}

.nav__link:hover::after,
.nav__link:focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}

.masthead__cta {
  padding: 0.6em 1.1em;
  font-size: var(--text-xs);
}

.masthead__cta-long {
  display: none;
}

@media (width < 26rem) {
  .brand__tag {
    display: none;
  }
}

@media (width >= 56rem) {
  .masthead__inner {
    flex-wrap: nowrap;
    padding-block: var(--space-2xs);
  }

  .nav {
    order: 0;
    width: auto;
    overflow: visible;
    border-block-start: 0;
  }

  .masthead__cta {
    padding: 0.85em 1.6em;
    font-size: var(--text-sm);
  }

  .masthead__cta-long {
    display: inline;
  }
}