.hf-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 4px;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1001;
  position: relative;
}
.hf-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink, #2a2620);
  border-radius: 2px;
  transition: transform 240ms ease, opacity 160ms ease;
  transform-origin: center;
}
.hf-hamburger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hf-hamburger.is-open span:nth-child(2) { opacity: 0; }
.hf-hamburger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.hf-mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  right: 0;
  width: min(75vw, 280px);
  height: 100dvh;
  background: var(--paper, #f4f1ea);
  z-index: 1000;
  padding: 80px 32px 40px;
  box-shadow: -4px 0 24px rgba(42,38,32,0.12);
  transform: translateX(100%);
  transition: transform 280ms cubic-bezier(0.4,0,0.2,1);
}
.hf-mobile-nav.is-open { transform: translateX(0); }
.hf-mobile-nav nav {
  display: flex !important;
  flex-direction: column;
  gap: 0;
}
.hf-mobile-nav nav a {
  display: block;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule-2, #e0d9c8);
  color: var(--ink-2, #4a463f);
  text-decoration: none;
  font-family: var(--serif, "Shippori Mincho", serif);
  font-size: 15px;
  letter-spacing: 0.12em;
  transition: color 160ms;
}
.hf-mobile-nav nav a:last-child { border-bottom: none; }
.hf-mobile-nav nav a:hover { color: var(--hover, #476e4b); }

.hf-mobile-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(42,38,32,0.35);
  z-index: 999;
  opacity: 0;
  transition: opacity 280ms ease;
  pointer-events: none;
}
.hf-mobile-overlay.is-open { opacity: 1; pointer-events: auto; }

@media (max-width: 640px) {
  .hf-header { grid-template-columns: auto 1fr auto !important; }
  .hf-hamburger { display: flex !important; }
  .hf-mobile-nav,
  .hf-mobile-overlay { display: block !important; }
}