body {
  font-family: system-ui, sans-serif;
  background: #0f0f1a;
  color: #ddd;
  margin: 0;
  padding: 2rem;
  text-align: center;
}

header h1 {
  color: #ffcc66;
  margin-bottom: 0.2rem;
}

.controls {
  margin: 2rem 0;
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

select, button {
  padding: 0.8rem 1.2rem;
  font-size: 1.1rem;
  border-radius: 8px;
  background: #222;
  color: white;
  border: none;
}

button {
  background: #ff8866;
  cursor: pointer;
  transition: 0.2s;
}

button:hover { background: #ffaa88; transform: scale(1.05); }

.piano, .guitar {
  margin: 2rem auto;
  max-width: 900px;
  background: #1a1a2e;
  padding: 1.5rem;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.key {
  display: inline-block;
  width: 40px;
  height: 180px;
  background: white;
  margin: 2px;
  border: 1px solid #333;
  border-radius: 4px;
  position: relative;
  vertical-align: top;
}

.key.black {
  background: #111;
  height: 120px;
  margin-left: -20px;
  z-index: 2;
  color: white;
}

.highlight { background: #ffcc66 !important; box-shadow: 0 0 15px #ffcc66; }

.guitar {
  display: grid;
  grid-template-columns: repeat(13, 1fr);
  gap: 4px;
}

.fret {
  background: #222;
  color: #aaa;
  padding: 8px;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #444;
}