body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: #111;
}

.app {
  width: 1100px;
  height: 650px;
  margin: 40px auto;
  background: #fff;
  display: grid;
  grid-template-columns: 300px 1fr;
  border: 1px solid #ddd;
}

.panel { padding: 18px; }
.left { border-right: 1px solid #ddd; }

.row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  font-size: 12px;
}

label { width: 90px; color: #222; }

input, select {
  font-size: 12px;
  padding: 4px 6px;
}

.buttons button {
  width: 90px;
  padding: 8px 10px;
  font-size: 12px;
  background: #111;
  color: #fff;
  border: none;
  cursor: pointer;
}

hr {
  border: none;
  border-top: 1px solid #ddd;
  margin: 14px 0;
}

.right {
  display: flex;
  justify-content: center;
  align-items: center;
}

.previewFrame {
  width: 720px;
  height: 520px;
  border: 1px solid #aaa;
  background: #fff;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

#canvas { image-rendering: pixelated; }

.stepReadout {
  position: absolute;
  left: 14px;
  bottom: 12px;
  font-size: 18px;
  font-weight: 700;
  color: #111;
}

.groupTitle {
  font-size: 12px;
  font-weight: 700;
  margin: 6px 0 6px;
}

.toggleRow {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 10px;
}

.toggle {
  width: 22px;
  height: 22px;
  border: 1px solid #aaa;
  background: #fff;
  display: grid;
  place-items: center;
  cursor: pointer;
  user-select: none;
  font-size: 11px;
}

.toggle.on {
  background: #111;
  color: #fff;
  border-color: #111;
}

.hint {
  font-size: 11px;
  color: #444;
  margin-top: 4px;
}