/* Local stacking order: background 0 → bird 1 → content 2.
   The header lives outside this isolated context at 20. */
.bird-layer{position:absolute;inset:0;z-index:var(--layer-bird,1);overflow:hidden;pointer-events:none;user-select:none;contain:paint}
.bird-flight{position:absolute;left:0;top:24%;width:42px;height:32px;opacity:0;will-change:transform;animation:bird-fly-across 30s linear 1.2s infinite}
.bird{display:block;width:100%;height:100%;overflow:visible;filter:drop-shadow(0 2px 2px #001b1b55)}
.bird-wing{transform-box:view-box;transform-origin:45% 58%;animation:bird-wingbeat .32s ease-in-out infinite alternate}
.bird-wing-far{animation-delay:-.12s}
.hero[data-bird-paused="true"] .bird-flight,.hero[data-bird-paused="true"] .bird-wing{animation-play-state:paused}
@keyframes bird-wingbeat{from{transform:rotate(-18deg) scaleY(.9)}to{transform:rotate(24deg) scaleY(-.25)}}
@keyframes bird-fly-across{
  0%{transform:translate3d(-64px,14px,0) rotate(-7deg);opacity:0}
  2%{opacity:.92}
  9%{transform:translate3d(15vw,-18px,0) rotate(-9deg)}
  18%{transform:translate3d(37vw,22px,0) rotate(6deg)}
  28%{transform:translate3d(62vw,-28px,0) rotate(-8deg)}
  40%{transform:translate3d(calc(100vw + 64px),0,0) rotate(4deg);opacity:.92}
  41%,100%{transform:translate3d(calc(100vw + 64px),0,0) rotate(0);opacity:0}
}
@media(max-width:540px){.bird-flight{width:33px;height:25px;top:20%}}
@media(prefers-reduced-motion:reduce){.bird-layer{display:none}.bird-flight,.bird-wing{animation:none;will-change:auto}}