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

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #000;
}

#hw {
  position: relative;
  width: 100vw;
  height: 100vh;
  cursor: crosshair;
  user-select: none;
  background: #000;
}

#hw canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.hw-hint {
  position: absolute;
  bottom: 14px;
  width: 100%;
  text-align: center;
  font-family: monospace;
  font-size: 10px;
  letter-spacing: 0.25em;
  color: rgba(255,255,255,0.2);
  pointer-events: none;
  animation: hint-pulse 3s ease-in-out infinite alternate;
}

@keyframes hint-pulse {
  from { opacity: 0.1; }
  to   { opacity: 0.5; }
}

.centered {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  animation: float-center 5s ease-in-out infinite;
}

@keyframes float-center {
  0%, 100% { transform: translate(-50%, -50%) translateY(0px); }
  50%       { transform: translate(-50%, -50%) translateY(-15px); }
}