* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background: #0f172a;
  color: #fff;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  overflow: hidden;
}

#game-container {
  position: relative;
  width: 400px;
  height: 600px;
  box-shadow: 0 0 30px rgba(0, 0, 0, 0.6);
  border-radius: 8px;
  overflow: hidden;
  background: #1e293b;
}

#game {
  display: block;
  width: 100%;
  height: 100%;
  background: #334155;
}

#ui {
  position: absolute;
  top: 10px;
  left: 10px;
  right: 10px;
  display: flex;
  justify-content: space-between;
  font-size: 14px;
  font-weight: 700;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.7);
  pointer-events: none;
  z-index: 2;
}

#overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: rgba(15, 23, 42, 0.92);
  text-align: center;
  z-index: 3;
}

#overlay h1 {
  margin: 0 0 10px;
  font-size: 36px;
  color: #38bdf8;
}

#overlay p {
  margin: 0 0 24px;
  line-height: 1.5;
  color: #cbd5e1;
}

#start-btn {
  padding: 12px 28px;
  font-size: 18px;
  font-weight: 700;
  color: #0f172a;
  background: #38bdf8;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.2s;
}

#start-btn:hover {
  background: #7dd3fc;
}

#overlay.hidden {
  display: none;
}