body {
  font-family: system-ui, sans-serif;
  margin: 0;
}

.header {
  position: relative;
  height: 40vh;
  background: linear-gradient(60deg, #543ab7, #00acc1);
}

.waves {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 15vh;
  min-height: 80px;
  max-height: 150px;
}

.content {
  height: 20vh;
  display: grid;
  place-items: center;
}

/* Ein Pfad (#wave-path), viermal per <use> eingebunden. Jede Kopie läuft auf
   demselben @keyframes, nur mit versetztem delay/duration — daraus entsteht
   der Tiefeneffekt, ohne vier separate Keyframes zu brauchen. */
@media (prefers-reduced-motion: no-preference) {
  .parallax > use {
    animation: move-forever 25s cubic-bezier(0.55, 0.5, 0.45, 0.5) infinite;
  }

  .parallax > use:nth-child(1) { animation-delay: -2s; animation-duration: 7s; }
  .parallax > use:nth-child(2) { animation-delay: -3s; animation-duration: 10s; }
  .parallax > use:nth-child(3) { animation-delay: -4s; animation-duration: 13s; }
  .parallax > use:nth-child(4) { animation-delay: -5s; animation-duration: 20s; }
}

@keyframes move-forever {
  0%   { transform: translate3d(-90px, 0, 0); }
  100% { transform: translate3d(85px, 0, 0); }
}