:root {
  --bg: #0e0f12;
  --panel: #16181d;
  --panel-2: #1d2026;
  --line: #2a2e36;
  --text: #e9ebef;
  --muted: #9aa0ab;
  --accent: #2f7d4f;
  --accent-2: #38a169;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html, body {
  margin: 0;
  height: 100%;
  font-family: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  overflow: hidden;
}

#app {
  display: grid;
  grid-template-columns: 1fr 360px;
  height: 100vh;
}

/* ---------- Stage ---------- */
#stage {
  position: relative;
  background: radial-gradient(120% 120% at 50% 20%, #2b2f37 0%, #15171c 60%, #0c0d10 100%);
  overflow: hidden;
}
#canvas-wrap { position: absolute; inset: 0; }
#canvas-wrap canvas { display: block; }

#topbar {
  position: absolute;
  top: 18px; left: 22px;
  display: flex; align-items: baseline; gap: 12px;
  pointer-events: none;
}
#topbar .brand { font-weight: 700; letter-spacing: .3px; font-size: 18px; }
#topbar .tag { color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: 1.5px; }

#hint {
  position: absolute;
  bottom: 18px; left: 0; right: 0;
  text-align: center;
  color: var(--muted);
  font-size: 12.5px;
  pointer-events: none;
}

#loading {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  color: var(--muted); font-size: 14px;
  background: var(--bg);
  transition: opacity .4s ease;
}
#loading.hidden { opacity: 0; pointer-events: none; }

/* ---------- Panel ---------- */
#panel {
  background: var(--panel);
  border-left: 1px solid var(--line);
  padding: 24px 22px;
  overflow-y: auto;
}
#panel h1 { font-size: 19px; margin: 4px 0 22px; }

.group { margin-bottom: 24px; }
.group-label {
  display: block;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1.3px;
  color: var(--muted);
  margin-bottom: 10px;
}

/* Segmented control */
.seg {
  display: flex;
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 4px;
  gap: 4px;
}
.seg button {
  flex: 1;
  border: 0;
  background: transparent;
  color: var(--muted);
  padding: 9px 6px;
  border-radius: 7px;
  font-size: 13px;
  cursor: pointer;
  transition: background .15s, color .15s;
}
.seg button:hover { color: var(--text); }
.seg button.active { background: var(--accent); color: #fff; }

/* Swatches */
.swatches {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 8px;
  margin-bottom: 12px;
}
.swatch {
  aspect-ratio: 1;
  border-radius: 8px;
  border: 2px solid transparent;
  cursor: pointer;
  position: relative;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.08);
  transition: transform .1s;
}
.swatch:hover { transform: scale(1.07); }
.swatch.active { border-color: #fff; }

.custom {
  display: flex; align-items: center; gap: 10px;
  font-size: 12.5px; color: var(--muted);
}
.custom input[type="color"] {
  width: 38px; height: 30px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--panel-2);
  padding: 2px;
  cursor: pointer;
}

/* Buttons */
.row { display: flex; gap: 8px; margin-bottom: 8px; }
.btn {
  flex: 1;
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 10px;
  font-size: 13px;
  cursor: pointer;
  transition: border-color .15s, background .15s;
}
.btn:hover { border-color: var(--muted); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-2); }

/* Photo tools */
.photo-tools { margin-top: 12px; }
.slider-row {
  display: grid;
  grid-template-columns: 80px 1fr;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
  font-size: 12.5px;
  color: var(--muted);
}
.slider-row input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: var(--line);
  outline: none;
}
.slider-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--accent-2);
  cursor: pointer;
  border: none;
}
.photo-tools .seg { margin-top: 10px; }
.hint-small {
  margin-top: 10px;
  font-size: 11.5px;
  color: var(--muted);
  text-align: center;
}

/* Summary */
.summary {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 16px;
  font-size: 13px;
  line-height: 1.7;
}
.summary .row-item { display: flex; justify-content: space-between; }
.summary .k { color: var(--muted); }
.summary .v { font-weight: 600; }
.summary .chip {
  display: inline-block; width: 12px; height: 12px;
  border-radius: 3px; vertical-align: middle; margin-left: 6px;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.15);
}

.panel-foot {
  margin-top: 18px;
  color: var(--muted);
  font-size: 11px;
  text-align: center;
}

@media (max-width: 820px) {
  #app { grid-template-columns: 1fr; grid-template-rows: 55vh 45vh; }
  #panel { border-left: 0; border-top: 1px solid var(--line); }
}