:root {
  --bg: #f6f6f6;
  --panel: #ffffff;
  --ink: #000000;
  --muted: #666666;
  --accent: #3661df;
  --line: #e5e5e5;
  --line-soft: #efefef;
  --font: 'Barlow Condensed', sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 13px;
  font-weight: 300;
  letter-spacing: 0.02em;
  height: 100%;
}

.app {
  display: grid;
  grid-template-rows: 1fr auto;
  height: 100vh;
  gap: 0;
}

/* ── Stage (canvas area) ────────────────────────────────────────── */
.stage {
  position: relative;
  background: var(--bg);
  overflow: hidden;
}

#render {
  display: block;
  width: 100%;
  height: 100%;
}

/* Brand mark, top-left over the stage */
.stage::before {
  content: 'Horizon Labs / STL Bicolor';
  position: absolute;
  top: 20px;
  left: 24px;
  font-family: var(--font);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  pointer-events: none;
  z-index: 2;
}
.stage::after {
  content: '';
  position: absolute;
  top: 20px;
  right: 24px;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  pointer-events: none;
  z-index: 2;
}

.dropzone {
  position: absolute;
  inset: 48px 24px 24px;
  border: 1px dashed var(--line);
  display: grid;
  place-items: center;
  pointer-events: none;
  opacity: 0;
  transition: opacity 120ms ease;
  background: rgba(246, 246, 246, 0.92);
  z-index: 3;
}

.dropzone.active {
  opacity: 1;
  pointer-events: auto;
  border-color: var(--accent);
}

.dropzone-inner {
  text-align: center;
  display: grid;
  gap: 6px;
}

.dropzone-inner strong {
  font-size: 32px;
  font-weight: 200;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.dropzone-inner span {
  font-size: 14px;
  font-weight: 300;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}

.badge {
  position: absolute;
  bottom: 20px;
  left: 24px;
  display: grid;
  gap: 4px;
  font-family: var(--font);
  font-size: 12px;
  font-weight: 300;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  pointer-events: none;
}

.badge-row em {
  font-style: normal;
  display: inline-block;
  width: 96px;
  color: var(--ink);
  font-weight: 500;
}

/* ── Panel (controls) ───────────────────────────────────────────── */
.panel {
  background: var(--panel);
  display: grid;
  grid-template-columns: auto 1fr 1fr 1fr auto;
  gap: 28px;
  padding: 24px 32px 28px;
  border-top: 1px solid var(--line);
  align-items: stretch;
}

.group {
  border: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
  align-content: start;
  min-width: 0;
}

.group legend {
  font-size: 11px;
  letter-spacing: 0.16em;
  font-weight: 500;
  text-transform: uppercase;
  color: var(--accent);
  padding: 0 0 6px 0;
}

.group label {
  display: grid;
  grid-template-columns: 78px 1fr 36px;
  align-items: center;
  gap: 10px;
  font-size: 12px;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink);
}

.group label.check {
  grid-template-columns: auto auto;
  gap: 8px;
  cursor: pointer;
}

.group label.check input { accent-color: var(--accent); }

.group .file-btn {
  /* Match the same row as upload */
  display: block;
}

/* Range sliders, Horizon style */
.group input[type="range"] {
  appearance: none;
  -webkit-appearance: none;
  width: 100%;
  height: 2px;
  background: var(--line);
  border-radius: 999px;
  outline: none;
  accent-color: var(--accent); /* fallback for non-webkit */
}
.group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
  box-shadow: 0 0 0 4px rgba(54, 97, 223, 0.12);
  transition: box-shadow 120ms ease;
}
.group input[type="range"]::-webkit-slider-thumb:hover {
  box-shadow: 0 0 0 6px rgba(54, 97, 223, 0.18);
}
.group input[type="range"]::-moz-range-thumb {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
}
.group input[type="range"]::-moz-range-track {
  height: 2px;
  background: var(--line);
}

/* Color pickers */
.group input[type="color"] {
  width: 36px;
  height: 22px;
  padding: 0;
  border: 1px solid var(--line);
  background: none;
  cursor: pointer;
  border-radius: 4px;
}

.group output {
  font-variant-numeric: tabular-nums;
  text-align: right;
  font-weight: 500;
  color: var(--ink);
  font-size: 12px;
}

/* Selects */
.group select {
  font-family: var(--font);
  font-size: 12px;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 100px;
  background: var(--panel);
  cursor: pointer;
}

/* Buttons — Horizon pill style */
.group button {
  font-family: var(--font);
  font-size: 12px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  padding: 9px 18px;
  border: 1px solid var(--ink);
  border-radius: 100px;
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  transition: background 120ms ease, color 120ms ease;
}
.group button:hover {
  background: var(--ink);
  color: var(--panel);
}

.group button.primary {
  background: var(--ink);
  color: var(--panel);
  font-weight: 600;
  padding: 12px 24px;
  border-color: var(--ink);
}
.group button.primary:hover {
  background: var(--accent);
  border-color: var(--accent);
}

/* Upload STL — pill, looks like a button */
.group label.file-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font);
  font-size: 12px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  padding: 9px 18px;
  border: 1px solid var(--ink);
  border-radius: 100px;
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  transition: background 120ms ease, color 120ms ease;
  grid-template-columns: 1fr;
}
.group label.file-btn:hover {
  background: var(--ink);
  color: var(--panel);
}
.group label.file-btn input { display: none; }

/* I/O group: stack actions with smaller gap */
.group-actions {
  gap: 8px;
  align-content: end;
}
.group-actions label:not(.file-btn) {
  grid-template-columns: auto auto;
  justify-content: space-between;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

/* Camera & Model: right-align Reset / Z-up under sliders */
.group-camera,
.group-model {
  align-content: start;
}
.group-camera button,
.group-model button {
  margin-top: 4px;
  justify-self: start;
}

/* ── Responsive fallbacks ───────────────────────────────────────── */
@media (max-width: 1380px) {
  .panel {
    grid-template-columns: auto 1fr 1fr 1fr auto;
    gap: 20px;
    padding: 20px 24px;
  }
  .group label { grid-template-columns: 64px 1fr 32px; gap: 8px; }
}

@media (max-width: 1180px) {
  .panel {
    grid-template-columns: 1fr 1fr 1fr;
    gap: 24px 28px;
  }
}

@media (max-width: 760px) {
  .panel {
    grid-template-columns: 1fr 1fr;
  }
}