.sprite {
  position: absolute;
  pointer-events: none;
  image-rendering: pixelated;
}
.sprite--player {
  background: #ffff00;
  border: 1px solid #806000;
  box-shadow: 0 0 0 1px #ffff00;
  z-index: 5;
}
.sprite--cursor {
  position: absolute;
  background: #00ff00;
  border: 1px solid #008800;
  box-shadow: 0 0 4px 1px #00ff00, inset 0 0 0 1px #ccffcc;
  animation: cursorPulse 0.4s steps(2) infinite;
  z-index: 4;
}
.sprite--enemy { z-index: 4; }
.sprite--virus {
  background: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 10 14'><circle cx='5' cy='8' r='3.5' fill='%2300aa00' stroke='%23004400' stroke-width='0.5'/><circle cx='3.7' cy='7' r='0.6' fill='%23000'/><circle cx='6.3' cy='7' r='0.6' fill='%23000'/><line x1='5' y1='4' x2='5' y2='2' stroke='%23004400' stroke-width='0.5'/><line x1='1.5' y1='8' x2='0.2' y2='8' stroke='%23004400' stroke-width='0.5'/><line x1='8.5' y1='8' x2='9.8' y2='8' stroke='%23004400' stroke-width='0.5'/></svg>") center/contain no-repeat;
}