:root {
  --sand: #E8D9C2;
  --paper: #F1E5D1;
  --ink: #241D17;
  --terracotta: #B0532A;
  --terracotta-deep: #8A4222;
  --clay: #6E5640;
  --hairline: #CDB48C;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: var(--sand);
  color: var(--ink);
  font-family: 'Inter', sans-serif;
  padding: 28px 16px 60px;
}

.page { max-width: 1100px; margin: 0 auto; }

.page-head { text-align: center; margin-bottom: 28px; }
.page-head h1 { font-size: 1.7rem; margin-bottom: 6px; }
.subtitle { color: var(--clay); font-size: 14px; }

.layout {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 24px;
  align-items: flex-start;
}

@media (max-width: 820px) {
  .layout { grid-template-columns: 1fr; }
}

/* ---------- PREVIEW PANEL ---------- */
.preview-panel {
  background: var(--paper);
  border: 1px solid var(--hairline);
  border-radius: 16px;
  padding: 24px;
  position: sticky;
  top: 20px;
}

/* ---------- STABLE GRID VIEWPORT ---------- */
.preview-stage {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 300px;
  max-height: 500px;
  overflow: auto;
  background-color: #141416;
  
  /* High contrast dark checkers */
  background-image: 
    linear-gradient(45deg, #0d0d0e 25%, transparent 25%, transparent 75%, #0d0d0e 75%),
    linear-gradient(45deg, #0d0d0e 25%, #141416 25%, #141416 75%, #0d0d0e 75%);
  background-size: 16px 16px;
  background-position: 0 0, 8px 8px;
  
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 16px;
  box-shadow: inset 0 4px 16px rgba(0,0,0,0.6);
}

#previewCanvas {
  display: block;
  margin: auto;
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  box-shadow: 0 12px 32px rgba(0,0,0,0.7);
}

.preview-actions { display: flex; flex-direction: column; gap: 8px; }
.btn-group { display: flex; gap: 10px; margin-top: 8px; }

.btn {
  flex: 1;
  padding: 11px 16px;
  border-radius: 10px;
  font-size: 13.5px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  font-family: inherit;
  text-align: center;
  transition: transform 0.15s ease, background 0.15s ease;
}
.btn.primary { background: var(--terracotta); color: var(--paper); }
.btn.primary:hover { background: var(--terracotta-deep); transform: translateY(-1px); }
.btn.secondary { background: transparent; border: 1.5px solid var(--hairline); color: var(--ink); }
.btn.secondary:hover { border-color: var(--terracotta); color: var(--terracotta-deep); }

/* ---------- CONTROLS ---------- */
.controls-panel { display: flex; flex-direction: column; gap: 16px; }

.control-group {
  background: var(--paper);
  border: 1px solid var(--hairline);
  border-radius: 14px;
  padding: 18px 20px;
}

.control-group h2 {
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--terracotta-deep);
  margin-bottom: 14px;
  font-weight: 600;
}

.field-label {
  display: block;
  font-size: 12.5px;
  color: var(--clay);
  margin: 10px 0 5px;
}

input[type="text"],
input[type="number"],
select {
  width: 100%;
  padding: 9px 11px;
  border-radius: 8px;
  border: 1.5px solid var(--hairline);
  background: var(--sand);
  color: var(--ink);
  font-family: inherit;
  font-size: 13.5px;
}
input[type="text"]:focus,
input[type="number"]:focus,
select:focus {
  outline: none;
  border-color: var(--terracotta);
}

input[type="file"] {
  width: 100%;
  padding: 8px;
  border-radius: 8px;
  border: 1.5px dashed var(--hairline);
  background: var(--sand);
  color: var(--clay);
  font-family: inherit;
  font-size: 12.5px;
}

.hint {
  font-size: 11.5px;
  color: var(--clay);
  opacity: 0.85;
  margin-top: 4px;
  line-height: 1.4;
}

.size-readout {
  font-family: 'JetBrains Mono', monospace;
  color: var(--terracotta-deep);
  font-weight: 500;
  margin-top: 6px;
}

.symbol-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 4px;
  max-height: 180px;
  overflow-y: auto;
  margin-top: 8px;
  padding: 6px;
  border: 1.5px solid var(--hairline);
  border-radius: 8px;
  background: var(--sand);
}

.symbol-btn {
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 17px;
  border: 1px solid transparent;
  border-radius: 6px;
  background: var(--paper);
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}
.symbol-btn:hover {
  background: var(--hairline);
  transform: scale(1.08);
}
.symbol-btn.selected {
  border-color: var(--terracotta);
  background: var(--terracotta);
  color: var(--paper);
}

#symbolSelectedPreview {
  font-weight: 600;
  color: var(--terracotta-deep);
  font-size: 15px;
}

input[type="color"] {
  width: 100%;
  height: 38px;
  border-radius: 8px;
  border: 1.5px solid var(--hairline);
  cursor: pointer;
  background: var(--sand);
}

input[type="range"] { width: 100%; accent-color: var(--terracotta); }

.checkbox-row {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13.5px;
  margin: 10px 0 4px;
  cursor: pointer;
  user-select: none;
}
.checkbox-row input { accent-color: var(--terracotta); width: 16px; height: 16px; }

.hidden { display: none !important; }

footer {
  text-align: center;
  margin-top: 40px;
  color: var(--clay);
  font-size: 12.5px;
}