.composition-container {
  margin: 15px 0;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 10px;
}
.zone-haut { padding: 8px; }
.zone-bas {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
  padding-top: 0;
  padding-bottom: 0;
  background: #f7f7cc;
  border-radius: 8px;
}
.btn-toggle {
  margin-top: 10px;
  padding: 6px 12px;
  background: #0073aa;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
}
.btn-toggle:hover { background: #005c8c; }