body {
  background: #181824;
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  margin: 0;
}
.tetris-container {
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  justify-content: center;
}
.side-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-left: 24px;
  margin-right: 24px;
}
.panel-label {
  font-size: 1em;
  color: #aaa;
  margin-bottom: 4px;
  margin-top: 12px;
}
#tetris {
  background: #222;
  border: 4px solid #444;
  box-shadow: 0 0 20px #000a;
  display: block;
  margin-bottom: 10px;
}
#next, #hold {
  background: #222;
  border: 2px solid #444;
  margin-bottom: 10px;
  display: block;
}
#score {
  font-size: 1.2em;
  margin-bottom: 10px;
}
#controls {
  font-size: 1em;
  color: #aaa;
  margin-bottom: 10px;
}
button {
  background: #444;
  color: #fff;
  border: none;
  padding: 8px 16px;
  margin: 0 5px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 1em;
}
button:hover {
  background: #666;
}
h1 {
  margin-bottom: 2px;
  font-size: 2em;
  letter-spacing: 2px;
}
#startMenu {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 1000;
  background: #111;
  border: 1px solid #333;
  padding: 16px 18px;
  border-radius: 8px;
  box-shadow: 0 6px 24px rgba(0,0,0,0.6);
}
