*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  background-color: #000;
  color: #fff;
  min-height: 100vh;
  display: grid;
  place-items: center;
}

.container {
  position: relative;
  width: 360px;
  aspect-ratio: 1;
  background: 
    linear-gradient(90deg, #000 8px, transparent, #000 12px) 0 0 / 20px 120px,
    linear-gradient(aqua 60px, magenta 0) 0 0 / 360px 120px;
}

.row {
  &:nth-child(odd) { --flipRow: 180deg; }

  i {
    --x: round(down, var(--i) / 2);

    position: absolute;
    left: calc(9px + var(--x) * 20px); top: calc(var(--r) * 60px);
    width: 2px; height: 8px;
    background-color: #fffa;
    transform-origin: top;
    animation: i 1s calc(var(--x) * -0.15s) infinite ease-in-out alternate;

    &:nth-child(odd) { --flipLine: -1; }
  }
}

@keyframes i {
  from { rotate: calc(45deg * var(--flipLine, 1) + var(--flipRow, 0deg)); }
  to { rotate: calc(135deg * var(--flipLine, 1) + var(--flipRow, 0deg)); }
}