.stl-layout {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 220px 1fr 1fr;
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  margin: 2rem;
  min-height: 600px;
}

.panel {
  background: var(--surface);
  padding: 1.5rem;
}

.panel-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
}

/* Model list */
#modelsContainer {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

#modelsContainer div {
  background: var(--surface2);
  border: 1px solid var(--border);
  padding: 0.75rem;
  cursor: pointer;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  transition: border-color 0.15s, color 0.15s;
}

#modelsContainer div:hover {
  border-color: var(--accent);
  color: var(--text);
}

#modelsContainer div.model-selected {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(74,158,255,0.06);
}

#modelsContainer img {
  display: block;
  margin: 0 auto 0.5rem;
  filter: invert(0.85) sepia(1) saturate(3) hue-rotate(185deg) brightness(1.1);
  width: 100px;
  height: 80px;
  object-fit: contain;
}

/* Param form */
#paramForm {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

#paramForm div {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

#paramForm label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

#paramForm input {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.5rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.15s;
}

#paramForm input:focus {
  border-color: var(--accent);
}

#paramSection h2,
#previewSection h2 {
  display: none; /* replaced by panel-label */
}

#generateBtn {
  width: 100%;
  padding: 0.75rem;
  background: var(--accent);
  color: #080808;
  border: none;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background 0.15s;
}

#generateBtn:hover { background: #5aaeff; }
#generateBtn:disabled { background: var(--border); color: var(--text-muted); cursor: not-allowed; }

#queueStatus {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
  min-height: 1.2em;
}

/* Preview */
#preview {
  width: 100%;
  height: 400px;
  background: var(--surface2);
  border: 1px solid var(--border);
}

#download-btn {
  margin-top: 1rem;
}

@media (max-width: 768px) {
  .stl-layout {
    grid-template-columns: 1fr;
    margin: 1rem;
  }
}

/* ── Action buttons row ── */
.btn-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  margin-bottom: 0.5rem;
}

#downloadBtn {
  width: 100%;
  margin-top: 1rem;
  padding: 0.65rem;
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

#downloadBtn:hover:not(:disabled) {
  background: var(--accent);
  color: #080808;
}

#generateBtn, #previewBtn {
  padding: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border: none;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

#generateBtn {
  background: var(--accent);
  color: #080808;
}

#generateBtn:hover:not(:disabled) { background: #5aaeff; }

#previewBtn {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}

#previewBtn:hover:not(:disabled) {
  background: var(--accent);
  color: #080808;
}

#generateBtn:disabled,
#previewBtn:disabled,
#downloadBtn:disabled {
  background: transparent;
  border-color: var(--border);
  color: var(--text-muted);
  cursor: not-allowed;
  opacity: 0.5;
}