body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #eef2f7;
  color: #333;
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

.mouse-field {
  flex: 1;
  position: relative;
  background: #ffffff;
}

.target {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  background: #ff4a4a;
  border: 4px solid #333;
  position: absolute;
  animation: blink 1s infinite;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 16px;
  color: white;
  font-weight: bold;
  user-select: none;
  -webkit-user-select: none;
}

@keyframes blink {
  50% { opacity: 0.4; }
}