body {
  height: auto;
  min-height: 100vh;
  overflow: auto;
}

.builder-shell {
  min-height: 100vh;
  height: auto;
}

.frame-editor {
  display: grid;
  gap: 16px;
  padding: clamp(14px, 2vw, 28px);
}

.builder-intro {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(280px, 0.7fr);
  gap: clamp(20px, 5vw, 72px);
  align-items: end;
  border-bottom: 1px solid var(--retui-project);
  padding: clamp(10px, 2vw, 24px) 0;
}

.builder-intro h1 {
  max-width: 1050px;
  margin: 8px 0 0;
  font-size: clamp(2.2rem, 4.8vw, 5rem);
}

.builder-intro p {
  margin: 0;
  color: var(--ink);
  font-size: 1.15rem;
}

.editor-top {
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(420px, 1.1fr);
  gap: 16px;
  align-items: stretch;
}

.editor-panel {
  min-width: 0;
  border: 1px solid color-mix(in srgb, var(--retui-project) 62%, var(--line));
  background: color-mix(in srgb, var(--retui-project) 4%, var(--pane));
}

.panel-heading {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: baseline;
  border-bottom: 1px solid var(--line);
  padding: 10px 12px;
}

.panel-heading h2 {
  margin: 0;
  color: var(--retui-project);
  font-size: 1.25rem;
}

.panel-heading span {
  color: var(--dim);
  font-size: 0.82rem;
}

.upload-zone {
  display: grid;
  gap: 3px;
  margin: 12px;
  border: 1px dashed var(--retui-project);
  background: color-mix(in srgb, var(--retui-project) 8%, transparent);
  padding: 14px;
  color: var(--muted);
  cursor: pointer;
}

.upload-zone.dragging {
  background: color-mix(in srgb, var(--retui-project) 18%, transparent);
}

.upload-zone input {
  width: 100%;
  margin-bottom: 6px;
}

.upload-zone strong {
  color: var(--ink);
}

.source-stage,
.preview-stage {
  position: relative;
  display: grid;
  min-height: 360px;
  place-items: center;
  margin: 12px;
  border: 1px solid var(--line);
  overflow: hidden;
}

.source-stage {
  background-color: #111;
  background-image: linear-gradient(45deg, #222 25%, transparent 25%), linear-gradient(-45deg, #222 25%, transparent 25%), linear-gradient(45deg, transparent 75%, #222 75%), linear-gradient(-45deg, transparent 75%, #222 75%);
  background-position: 0 0, 0 8px, 8px -8px, -8px 0;
  background-size: 16px 16px;
}

.source-stage canvas {
  display: block;
  width: auto;
  max-width: 100%;
  height: auto;
  max-height: 500px;
  cursor: crosshair;
  touch-action: none;
}

.source-stage.empty canvas {
  visibility: hidden;
}

.source-stage p {
  position: absolute;
  margin: 0;
  color: var(--dim);
}

.source-stage:not(.empty) p {
  display: none;
}

.guide-grid,
.side-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(72px, 1fr));
  gap: 8px;
}

.guide-grid {
  padding: 0 12px 12px;
}

.guide-grid button {
  align-self: end;
}

.preview-controls {
  display: grid;
  grid-template-columns: minmax(190px, 1fr) auto auto;
  gap: 12px;
  align-items: end;
  padding: 12px;
}

.preview-controls label,
.control-group label,
.guide-grid label {
  display: grid;
  gap: 4px;
  color: var(--muted);
}

.preview-controls fieldset {
  display: flex;
  gap: 9px;
  min-width: 0;
  margin: 0;
  border: 0;
  padding: 0;
}

.preview-controls legend {
  margin-bottom: 3px;
  color: var(--muted);
}

.preview-controls fieldset label,
.check-row {
  display: flex;
  gap: 5px;
  align-items: center;
  white-space: nowrap;
}

.preview-controls input[type="radio"],
.check-row input {
  width: auto;
  min-height: 0;
  margin: 0;
}

.preview-stage {
  min-height: 430px;
  background: #050706;
}

.preview-stage.theme-light {
  background: #e8e5df;
}

.preview-stage.theme-checker {
  background-color: #bbb;
  background-image: linear-gradient(45deg, #eee 25%, transparent 25%), linear-gradient(-45deg, #eee 25%, transparent 25%), linear-gradient(45deg, transparent 75%, #eee 75%), linear-gradient(-45deg, transparent 75%, #eee 75%);
  background-position: 0 0, 0 12px, 12px -12px, -12px 0;
  background-size: 24px 24px;
}

.preview-stage canvas {
  display: block;
  width: min(100%, 820px);
  height: auto;
}

.preview-note,
.privacy-note,
.status-message {
  margin: 0;
  padding: 0 12px 12px;
  color: var(--dim);
}

.slice-legend {
  margin: -2px 12px 12px;
  color: var(--dim);
  text-align: center;
}

.slice-legend strong {
  color: var(--ink);
}

.controls-panel {
  padding-bottom: 14px;
}

.preset-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 12px;
}

.controls-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  padding: 0 12px;
}

.control-group {
  display: grid;
  align-content: start;
  gap: 10px;
  border: 1px solid var(--line);
  padding: 12px;
}

.control-group h3 {
  margin: 0;
  color: var(--cyan);
}

.side-grid {
  grid-template-columns: repeat(2, minmax(72px, 1fr));
}

.hidden {
  display: none;
}

.manifest-summary {
  min-height: 78px;
  border-left: 3px solid var(--retui-project);
  background: #070908;
  padding: 10px;
  color: var(--ink);
  white-space: pre-wrap;
}

.download-button {
  border-color: var(--retui-project);
  background: var(--retui-project);
  color: #050505;
  font-weight: 700;
}

.download-button:disabled {
  border-color: var(--line);
  background: var(--pane-soft);
  color: var(--dim);
  cursor: not-allowed;
}

.status-message.error {
  color: var(--red);
}

.status-message.success {
  color: var(--green);
}

@media (max-width: 980px) {
  .builder-intro,
  .editor-top,
  .controls-grid {
    grid-template-columns: 1fr;
  }

  .preview-controls {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .frame-editor {
    padding: 8px;
  }

  .source-stage,
  .preview-stage {
    min-height: 280px;
  }

  .guide-grid {
    grid-template-columns: repeat(2, minmax(72px, 1fr));
  }

  .guide-grid button {
    grid-column: 1 / -1;
  }
}