/* ─────────────────────────────────────────────────────────────
   CIE hamburger → X morph + sliding nav panel.
   Snappy morph (~360ms expo), panel slide, backdrop, focus trap,
   aria-expanded, Escape / backdrop click to close.
   ───────────────────────────────────────────────────────────── */

/* Hamburger button — three lines that morph to X */
.cie-hamburger {
  width: 44px;
  height: 44px;
  border-radius: var(--cie-r-pill);
  background: var(--cie-btn);
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 0;
  position: relative;
  transition: background-color 150ms linear;
  z-index: 70;
}
.cie-hamburger:hover {
  background: var(--cie-btn-hover);
}
.cie-hamburger:active {
  transform: scale(0.96);
}

/* Three lines */
.cie-hamburger__line {
  width: 18px;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition:
    transform var(--cie-t-move) var(--cie-ease-expo),
    opacity var(--cie-t-fast) linear;
  transform-origin: center;
}

/* Open state: morph to X */
.cie-hamburger[aria-expanded="true"] .cie-hamburger__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.cie-hamburger[aria-expanded="true"] .cie-hamburger__line:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.cie-hamburger[aria-expanded="true"] .cie-hamburger__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Nav panel — slides in from side */
.cie-nav-panel {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(85vw, 360px);
  background: var(--cie-paper);
  color: var(--cie-ink);
  padding: var(--cie-s-24);
  transform: translateX(100%);
  visibility: hidden;
  z-index: 65;
  overflow-y: auto;
  overscroll-behavior: contain;
  transition:
    transform var(--cie-t-move) var(--cie-ease-expo),
    visibility 0ms linear var(--cie-t-move);
  box-shadow: -4px 0 16px rgba(11, 11, 11, 0.12);
}
.cie-nav-panel.is-open {
  transform: translateX(0);
  visibility: visible;
  transition:
    transform var(--cie-t-move) var(--cie-ease-expo),
    visibility 0ms linear 0ms;
}

/* Nav panel variant: from left */
.cie-nav-panel--left {
  right: auto;
  left: 0;
  transform: translateX(-100%);
  box-shadow: 4px 0 16px rgba(11, 11, 11, 0.12);
}
.cie-nav-panel--left.is-open {
  transform: translateX(0);
}

/* Nav panel variant: ink */
.cie-nav-panel--ink {
  background: var(--cie-ink);
  color: var(--cie-paper);
  box-shadow: inset 0 0 0 1px var(--cie-stroke), -4px 0 16px rgba(11, 11, 11, 0.12);
}

/* Nav panel header */
.cie-nav-panel__head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--cie-s-16);
  margin-bottom: var(--cie-s-28);
}
.cie-nav-panel__title {
  font-size: var(--cie-text-cell);
  font-weight: 300;
  font-variation-settings: 'wght' 300;
  letter-spacing: -0.03em;
}

/* Nav panel content */
.cie-nav-panel__nav {
  display: grid;
  gap: 0;
}
.cie-nav-panel__nav a {
  padding: var(--cie-s-16) 0;
  border-bottom: 1px solid var(--cie-stroke);
  font-size: var(--cie-text-row);
  font-weight: 300;
  font-variation-settings: 'wght' 300;
  letter-spacing: -0.02em;
  transition: 
    font-variation-settings 320ms var(--cie-ease-out),
    transform 180ms var(--cie-ease-out);
}
.cie-nav-panel__nav a:first-child {
  border-top: 1px solid var(--cie-stroke);
}
@media (hover: hover) {
  .cie-nav-panel__nav a:hover {
    font-variation-settings: 'wght' 500;
    transform: translateX(4px);
  }
}

/* Nav backdrop */
.cie-nav-backdrop {
  position: fixed;
  inset: 0;
  z-index: 60;
  background: rgba(11, 11, 11, 0.45);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--cie-t-move) linear;
}
.cie-nav-backdrop.is-on {
  opacity: 1;
  pointer-events: auto;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .cie-hamburger,
  .cie-hamburger__line,
  .cie-nav-panel,
  .cie-nav-backdrop {
    transition: none !important;
  }
  .cie-hamburger:active {
    transform: none;
  }
  .cie-nav-panel {
    transform: translateX(0);
  }
  .cie-nav-panel:not(.is-open) {
    visibility: hidden;
  }
}