/* Fullscreen, 9:16 mobile target */
html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: Arial, Helvetica, sans-serif;
  background: #000;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

#boulderdash {
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
}

#canvas {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  flex: 1;
  touch-action: none;
  -webkit-touch-callout: none;
  user-select: none;
}

/* Overlay header: hidden (instructions + level selector) */
#header {
  display: none;
}
#header img {
  cursor: pointer;
  width: 1.5em;
  height: 1.5em;
  opacity: 0.9;
}
#header img.disabled { cursor: default; opacity: 0.4; }
#header img:active { opacity: 0.7; }
#description { flex: 1; font-style: italic; }
#help { color: #8af; text-decoration: none; }

#keys {
  display: none;
}

#stats {
  position: fixed;
  top: 0;
  right: 0;
  z-index: 20;
  pointer-events: none;
}

#back { color: #8af; font-size: 10pt; padding-left: 1em; }
#instructions           { padding: 1em; font-size: 12pt; width: 40em; }
#instructions ul li     { padding: 1em 0.5em; list-style-type: none; vertical-align: middle; border-top: 1px solid #CCC; min-height: 2em; }
#instructions ul li img { width: 32px; height: 32px; float: left; margin-right: 8px; border: 2px solid black; }
#instructions #keys li  { min-height: 0; border: 0; padding: 0; margin-left: 2em; list-style-type: disc; }