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

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #02060c;
}

#tank {
  display: block;
  width: 100vw;
  height: 100vh;
  cursor: crosshair;
}

#hud {
  position: fixed;
  right: 16px;
  bottom: 14px;
  text-align: right;
  font-family: "SFMono-Regular", "Menlo", "Consolas", monospace;
  font-size: 12px;
  line-height: 1.55;
  letter-spacing: 0.04em;
  color: #bfe8ff;
  opacity: 0.42;
  text-shadow: 0 0 6px rgba(0, 40, 70, 0.8);
  pointer-events: none;
  user-select: none;
}

#hud-phase { font-size: 13px; letter-spacing: 0.18em; }

#hint {
  position: fixed;
  left: 16px;
  bottom: 14px;
  font-family: "SFMono-Regular", "Menlo", "Consolas", monospace;
  font-size: 11px;
  letter-spacing: 0.06em;
  color: #7fb8d8;
  opacity: 0.28;
  pointer-events: none;
  user-select: none;
  transition: opacity 1.2s ease;
}

#hint.fade { opacity: 0; }

#error {
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  max-width: 80vw;
  font-family: "SFMono-Regular", "Menlo", "Consolas", monospace;
  font-size: 13px;
  line-height: 1.6;
  color: #ff6b6b;
  text-align: center;
  white-space: pre-wrap;
  display: none;
}

#title {
  position: fixed;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  pointer-events: none;
  user-select: none;
  font-family: "SFMono-Regular", "Menlo", "Consolas", monospace;
  color: #cfeaff;
  text-align: center;
  opacity: 0;
  animation: titlefade 12s ease forwards;
}

#title .t-main {
  font-size: 32px;
  letter-spacing: 0.42em;
  text-indent: 0.42em;
  text-shadow: 0 0 28px rgba(40, 130, 180, 0.85), 0 0 4px rgba(180, 230, 255, 0.6);
}

#title .t-sub {
  font-size: 12px;
  letter-spacing: 0.36em;
  text-indent: 0.36em;
  opacity: 0.6;
}

@keyframes titlefade {
  0% { opacity: 0; }
  14% { opacity: 0.95; }
  62% { opacity: 0.95; }
  100% { opacity: 0; }
}