:root {
  color-scheme: dark;
  --bg: #111218;
  --panel: #1a1d27;
  --panel-2: #222638;
  --text: #f3f5ff;
  --muted: #aeb6d9;
  --line: #343a55;
  --accent: #8fb3ff;
  --danger: #ff9a9a;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background: radial-gradient(circle at top, #20243a, var(--bg) 55%);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button, input, select {
  font: inherit;
}

button {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.65rem 0.8rem;
  color: var(--text);
  background: var(--panel-2);
  cursor: pointer;
}

button:hover:not(:disabled), .file-button:hover {
  border-color: var(--accent);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.45;
}

input, select {
  width: 100%;
  margin-top: 0.35rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.55rem 0.65rem;
  color: var(--text);
  background: #0f111a;
}

input[type="range"] { padding: 0; }
input[type="checkbox"] { width: auto; margin: 0; }
input:disabled { opacity: 0.5; cursor: not-allowed; }

code {
  padding: 0.1rem 0.3rem;
  border-radius: 6px;
  background: #0b0d13;
}

.app {
  width: min(1280px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 24px 0;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 16px;
}

h1, h2, p { margin: 0; }
h1 { font-size: clamp(1.6rem, 4vw, 2.5rem); }
h2 { font-size: 1rem; margin-bottom: 0.8rem; }
.topbar p { color: var(--muted); margin-top: 0.35rem; }

.file-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 0.85rem 1rem;
  background: var(--panel-2);
  cursor: pointer;
}
.file-button input { display: none; }

.drop-zone {
  display: grid;
  gap: 0.25rem;
  place-items: center;
  margin-bottom: 16px;
  padding: 18px;
  border: 1px dashed var(--line);
  border-radius: 18px;
  background: rgba(26, 29, 39, 0.65);
  color: var(--muted);
  text-align: center;
}
.drop-zone.dragover {
  border-color: var(--accent);
  background: rgba(143, 179, 255, 0.12);
}

.workspace {
  display: grid;
  grid-template-columns: 390px 1fr;
  gap: 16px;
  align-items: start;
}

.panel, .preview-panel {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(26, 29, 39, 0.88);
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.28);
}

.panel {
  display: grid;
  gap: 1px;
  overflow: hidden;
}

.group {
  padding: 16px;
  background: rgba(26, 29, 39, 0.86);
}

.group label {
  display: block;
  margin-top: 0.8rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.checkbox-row {
  display: flex !important;
  align-items: center;
  gap: 0.55rem;
}

.actions-row, .button-grid {
  display: grid;
  gap: 8px;
  margin-top: 0.8rem;
}

.actions-row { grid-template-columns: 1fr 1fr; }
.button-grid { grid-template-columns: repeat(4, 1fr); }

.group > button {
  width: 100%;
  margin-top: 0.55rem;
}

.value-label {
  float: right;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.hint {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1.35;
}

.preview-panel {
  min-height: 620px;
  padding: 16px;
}

.preview-wrap {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 560px;
  overflow: auto;
  border-radius: 14px;
  background:
    linear-gradient(45deg, rgba(255,255,255,0.05) 25%, transparent 25%),
    linear-gradient(-45deg, rgba(255,255,255,0.05) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, rgba(255,255,255,0.05) 75%),
    linear-gradient(-45deg, transparent 75%, rgba(255,255,255,0.05) 75%);
  background-size: 24px 24px;
  background-position: 0 0, 0 12px, 12px -12px, -12px 0;
  background-color: #151722;
  cursor: grab;
}

.preview-wrap.dragging { cursor: grabbing; }

#renderCanvas {
  display: none;
  width: 256px;
  height: 256px;
  max-width: 100%;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

.empty-state {
  position: absolute;
  color: var(--muted);
  pointer-events: none;
}

.status {
  min-height: 1.5rem;
  margin-top: 12px;
  color: var(--muted);
  font-size: 0.9rem;
}

.status.error { color: var(--danger); }
.status.ok { color: #b7ffc9; }

@media (max-width: 900px) {
  .topbar { flex-direction: column; align-items: stretch; }
  .workspace { grid-template-columns: 1fr; }
  .preview-panel { min-height: 420px; }
  .preview-wrap { min-height: 360px; }
}