:root {
  --bg: #16181c;
  --panel: #101216;
  --panel-2: #1a1d23;
  --btn: #24272e;
  --btn-hover: #2f333c;
  --accent: #f39a19;
  --hover: #74b8ff;
  --text: #ecedf0;
  --dim: #9aa0ab;
  --left-w: 268px;
  --right-w: 212px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font: 13px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}

/* ------------------------------------------------------------ viewport */
/* the canvas lives *between* the panels so the model centres in the area
   the user can actually see, instead of behind the side panels */
#viewport {
  position: fixed;
  top: 0; bottom: 0;
  left: var(--left-w);
  right: var(--right-w);
}
#scene { display: block; width: 100%; height: 100%; touch-action: none; }

#hint {
  position: absolute;
  left: 50%;
  bottom: 14px;
  transform: translateX(-50%);
  color: var(--dim);
  font-size: 11px;
  background: rgba(0,0,0,.35);
  padding: 5px 12px;
  border-radius: 999px;
  pointer-events: none;
  white-space: nowrap;
  transition: opacity .5s;
}

#loading {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 14px;
  background: var(--bg);
  z-index: 40;
  transition: opacity .4s;
}
#loading.done { opacity: 0; pointer-events: none; }
#loading-text { color: var(--dim); font-size: 12px; }
.spinner {
  width: 30px; height: 30px;
  border: 3px solid #2b2f37;
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* -------------------------------------------------------------- panels */
.panel {
  position: fixed;
  top: 0;
  bottom: 0;
  background: rgba(16,18,22,.94);
  backdrop-filter: blur(8px);
  display: flex;
  flex-direction: column;
  z-index: 20;
  border-color: #23262d;
  border-style: solid;
  border-width: 0;
}
#left  { left: 0;  width: var(--left-w);  border-right-width: 1px; }
#right { right: 0; width: var(--right-w); border-left-width: 1px; }

.panel-head { padding: 14px 14px 10px; border-bottom: 1px solid #23262d; }
.panel-head h1 { margin: 0; font-size: 15px; letter-spacing: .06em; font-weight: 650; }
.panel-head h1 span { display: block; font-size: 10px; color: var(--dim); letter-spacing: .04em; font-weight: 400; }
.panel-head h2 { margin: 0; font-size: 13px; letter-spacing: .08em; font-weight: 650; }

.panel-body { padding: 12px 14px 24px; overflow-y: auto; overflow-x: hidden; flex: 1; }
.panel-body::-webkit-scrollbar { width: 9px; }
.panel-body::-webkit-scrollbar-thumb { background: #2b2f37; border-radius: 9px; }
.panel-body::-webkit-scrollbar-track { background: transparent; }

.section-label {
  font-size: 10.5px;
  letter-spacing: .07em;
  color: var(--dim);
  text-transform: uppercase;
  margin-bottom: 10px;
  min-height: 14px;
}
.section-label.active { color: var(--accent); }

.field { margin-bottom: 16px; }

.select {
  width: 100%;
  background: var(--btn);
  color: var(--text);
  border: 1px solid #2b2f37;
  border-radius: 6px;
  padding: 8px 10px;
  font: inherit; font-size: 12.5px;
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6'%3E%3Cpath fill='%239aa0ab' d='M0 0l5 6 5-6z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
}
.select:hover { background-color: var(--btn-hover); }
.select:focus { outline: none; border-color: var(--accent); }
.mini { display: block; font-size: 10.5px; color: var(--dim); margin-bottom: 6px; }
.mini b { color: var(--text); font-weight: 600; }

/* -------------------------------------------------------------- search */
.search-row { display: flex; gap: 5px; }
#search {
  flex: 1; min-width: 0;
  background: var(--panel-2);
  border: 1px solid #2b2f37;
  color: var(--text);
  border-radius: 6px;
  padding: 6px 8px;
  font: inherit;
  font-size: 12px;
}
#search:focus { outline: none; border-color: var(--accent); }
#search-clear {
  width: 28px;
  background: var(--btn);
  border: none; color: var(--dim);
  border-radius: 6px; cursor: pointer;
  font-size: 15px; line-height: 1;
}
#search-clear:hover { background: var(--btn-hover); color: var(--text); }

/* ------------------------------------------------------------ swatches */
.swatch-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 5px;
  max-height: 232px;
  overflow-y: auto;
  padding: 3px;
  margin-bottom: 16px;
  background: #0c0e11;
  border-radius: 8px;
}
.swatch-grid::-webkit-scrollbar { width: 8px; }
.swatch-grid::-webkit-scrollbar-thumb { background: #2b2f37; border-radius: 8px; }

.swatch {
  position: relative;
  aspect-ratio: 1;
  border-radius: 5px;
  border: 2px solid transparent;
  background: #23262d center/cover no-repeat;
  cursor: pointer;
  padding: 0;
  transition: border-color .12s, transform .08s;
}
.swatch:hover { transform: scale(1.06); }
.swatch.active { border-color: var(--accent); }
.swatch .tip {
  position: absolute;
  bottom: calc(100% + 5px);
  left: 50%;
  transform: translateX(-50%);
  background: #000;
  color: #fff;
  font-size: 10px;
  padding: 3px 7px;
  border-radius: 4px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity .12s;
  z-index: 5;
}
.swatch:hover .tip { opacity: .92; }
.empty-note { grid-column: 1/-1; color: var(--dim); font-size: 11px; padding: 10px; text-align: center; }

/* ------------------------------------------------------------- palette */
.palette { display: grid; grid-template-columns: repeat(8, 1fr); gap: 4px; margin-bottom: 8px; }
.chip {
  aspect-ratio: 1;
  border-radius: 4px;
  border: 2px solid transparent;
  cursor: pointer;
  padding: 0;
  transition: transform .08s, border-color .12s;
}
.chip:hover { transform: scale(1.12); }
.chip.active { border-color: var(--accent); }

.custom-color {
  display: flex; align-items: center; gap: 8px;
  background: var(--btn);
  border-radius: 6px;
  padding: 5px 8px;
  cursor: pointer;
  font-size: 11.5px;
  color: var(--dim);
}
.custom-color:hover { background: var(--btn-hover); color: var(--text); }
.custom-color input[type=color] {
  width: 26px; height: 22px; padding: 0;
  border: none; background: none; cursor: pointer;
}

/* -------------------------------------------------------------- ranges */
input[type=range] {
  width: 100%;
  -webkit-appearance: none; appearance: none;
  background: transparent; cursor: pointer;
}
input[type=range]::-webkit-slider-runnable-track {
  height: 5px; background: #2b2f37; border-radius: 4px;
}
input[type=range]::-moz-range-track { height: 5px; background: #2b2f37; border-radius: 4px; }
input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px; height: 14px; margin-top: -4.5px;
  background: var(--accent); border-radius: 50%; border: none;
}
input[type=range]::-moz-range-thumb {
  width: 14px; height: 14px; background: var(--accent);
  border-radius: 50%; border: none;
}
input[type=range]:disabled { opacity: .4; cursor: not-allowed; }

/* ----------------------------------------------------------- backdrops */
.backdrops { display: grid; grid-template-columns: repeat(4, 1fr); gap: 5px; }
.backdrop {
  height: 22px; border-radius: 5px; cursor: pointer;
  border: 2px solid transparent; padding: 0;
}
.backdrop.active { border-color: var(--accent); }

/* ------------------------------------------------------------- buttons */
.row-buttons { display: flex; gap: 6px; }
.btn {
  flex: 1;
  background: var(--btn);
  color: var(--text);
  border: none; border-radius: 6px;
  padding: 8px 6px;
  font: inherit; font-size: 11.5px;
  cursor: pointer;
}
.btn:hover { background: var(--btn-hover); }

/* -------------------------------------------------------------- layers */
.layer {
  display: flex; align-items: center; gap: 6px;
  margin-bottom: 5px;
}
.layer .eye {
  width: 26px; height: 28px; flex: none;
  background: var(--panel-2);
  border: none; border-radius: 5px;
  color: var(--text); cursor: pointer;
  font-size: 12px; line-height: 1;
  display: grid; place-content: center;
}
.layer .eye:hover { background: var(--btn-hover); }
.layer.hidden .eye { color: #5a606b; }
.layer .name {
  flex: 1; min-width: 0;
  background: var(--btn);
  border: none; border-radius: 5px;
  color: var(--text);
  text-align: left;
  padding: 7px 9px;
  font: inherit; font-size: 11.5px;
  cursor: pointer;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.layer .name:hover { background: var(--btn-hover); }
.layer.selected .name { background: var(--accent); color: #14161a; font-weight: 600; }
.layer.hidden .name { color: #5a606b; text-decoration: line-through; }
.layer .dot {
  width: 12px; height: 12px; flex: none;
  border-radius: 3px;
  border: 1px solid rgba(255,255,255,.18);
}

/* -------------------------------------------------------------- mobile */
.mobile-toggle { display: none; }

@media (max-width: 900px) {
  #viewport { left: 0; right: 0; }   /* panels become overlays */
  .panel {
    transform: translateX(-100%);
    transition: transform .22s ease;
    width: min(84vw, 300px);
    z-index: 30;
  }
  #right { transform: translateX(100%); }
  .panel.open { transform: none; }
  .mobile-toggle {
    display: grid; place-content: center;
    position: fixed; bottom: 16px;
    width: 46px; height: 46px;
    border-radius: 50%;
    border: 1px solid #2b2f37;
    background: rgba(16,18,22,.92);
    color: var(--text);
    font-size: 18px;
    cursor: pointer;
    z-index: 35;
  }
  #toggle-left { left: 16px; }
  #toggle-right { right: 16px; }
  #hint { bottom: 74px; font-size: 10px; }
}