:root {
  --bg: #f0ebd8;
  --surface: #f7f4e6;
  --surface-2: #e6e0c8;
  --fg: #0d1321;
  --muted: #3e5c76;
  --border: #d4ccb0;
  --accent: #1d2d44;
  --accent-hover: #2a3d57;
  --accent-tint: rgba(29, 45, 68, 0.08);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  color-scheme: light;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--fg);
  height: 100vh;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── App shell ─────────────────────────────────────────── */
.app-container {
  display: flex;
  height: 100vh;
}

/* ── Sidebar ───────────────────────────────────────────── */
.sidebar {
  width: 280px;
  background: var(--surface);
  padding: 16px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
  border-right: 1px solid var(--border);
  flex-shrink: 0;
}

.hub-link {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.85em;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: color 0.15s ease;
}
.hub-link:hover { color: var(--accent); }

h1 {
  color: var(--accent);
  font-size: 1.25em;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 3px;
}

.subtitle {
  color: var(--muted);
  font-size: 0.82em;
}

/* ── Sidebar sections ──────────────────────────────────── */
.section {
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 13px;
  border: 1px solid var(--border);
}

.section h3 {
  color: var(--accent);
  font-size: 0.78em;
  font-weight: 600;
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ── Upload / drop zone ────────────────────────────────── */
.upload-area {
  border: 2px dashed var(--border);
  border-radius: var(--radius-sm);
  padding: 24px 12px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.18s ease, background 0.18s ease;
  color: var(--fg);
}

.upload-area:hover,
.upload-area.dragover {
  background: var(--accent-tint);
  border-color: var(--accent);
}

.upload-area p {
  color: var(--muted);
  font-size: 0.82em;
  margin-top: 8px;
}

.upload-area strong {
  font-size: 0.9em;
}

.upload-icon {
  font-size: 2.2em;
  margin-bottom: 8px;
  display: block;
}

input[type="file"] { display: none; }

/* ── Control groups (sliders, labels) ─────────────────── */
.control-group {
  margin-bottom: 10px;
}
.control-group:last-child { margin-bottom: 0; }

.control-group label {
  display: block;
  font-size: 0.78em;
  color: var(--muted);
  margin-bottom: 4px;
}

.control-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

input[type="range"] {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 4px;
  background: var(--accent);
  border-radius: 2px;
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--surface);
  border: 1.5px solid var(--accent);
  cursor: pointer;
  box-shadow: 0 1px 3px rgba(0,0,0,0.15);
}
input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--surface);
  border: 1.5px solid var(--accent);
  cursor: pointer;
  box-shadow: 0 1px 3px rgba(0,0,0,0.15);
}

input[type="color"] {
  width: 36px;
  height: 28px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: transparent;
  padding: 2px;
}

.range-value {
  width: 38px;
  text-align: right;
  font-size: 0.78em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

/* ── Buttons ──────────────────────────────────────────── */
button {
  background: var(--surface);
  color: var(--fg);
  border: 1px solid var(--border);
  padding: 7px 13px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.82em;
  font-weight: 500;
  font-family: inherit;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
  width: 100%;
}
button:hover {
  background: var(--surface-2);
  border-color: var(--accent);
  color: var(--accent);
}

button.secondary {
  background: var(--bg);
  border-color: var(--border);
}
button.secondary:hover {
  background: var(--surface-2);
  border-color: var(--accent);
  color: var(--accent);
}

.btn-row {
  display: flex;
  gap: 7px;
}
.btn-row button { flex: 1; }

/* ── Toggle buttons ───────────────────────────────────── */
.toggle-btn {
  padding: 6px 10px;
  font-size: 0.78em;
}

.toggle-btn.active {
  background: var(--accent);
  color: var(--surface);
  border-color: var(--accent);
}
.toggle-btn.active:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: var(--surface);
}

/* ── Measure buttons ──────────────────────────────────── */
.measure-btn {
  padding: 8px 10px;
  font-size: 0.78em;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
}
.measure-btn .icon {
  font-size: 1.15em;
}
.measure-btn.active {
  background: var(--accent);
  color: var(--surface);
  border-color: var(--accent);
}
.measure-btn.active:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: var(--surface);
}

/* ── Measurement result card ───────────────────────────── */
.measurement-result {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  margin-top: 10px;
}
.measurement-result .label {
  font-size: 0.72em;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 3px;
}
.measurement-result .value {
  font-size: 1.05em;
  color: var(--accent);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}
.measurement-result .sub-value {
  font-size: 0.82em;
  color: var(--muted);
  margin-top: 3px;
  font-variant-numeric: tabular-nums;
}

.measurement-hint {
  font-size: 0.75em;
  color: var(--muted);
  margin-top: 8px;
  padding: 7px 9px;
  background: var(--accent-tint);
  border-radius: var(--radius-sm);
  line-height: 1.45;
}

/* ── Viewer area ──────────────────────────────────────── */
.viewer-container {
  flex: 1;
  position: relative;
  background: #0d1321;
  overflow: hidden;
}

#canvas-container {
  width: 100%;
  height: 100%;
  cursor: default;
}
#canvas-container.measure-mode {
  cursor: crosshair;
}

canvas { display: block; }

/* ── Info bar (bottom of canvas) ──────────────────────── */
.info-bar {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(247, 244, 230, 0.93);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  padding: 10px 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--border);
  font-size: 0.82em;
  color: var(--fg);
}
.info-item {
  display: flex;
  align-items: center;
  gap: 6px;
}
.info-label { color: var(--muted); }
.info-value {
  color: var(--accent);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}
.dimensions {
  display: flex;
  gap: 16px;
}

/* ── Loading overlay ──────────────────────────────────── */
.loading-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(13, 19, 33, 0.88);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 100;
}
.loading-overlay.hidden { display: none; }

.spinner {
  width: 44px;
  height: 44px;
  border: 3px solid rgba(29, 45, 68, 0.3);
  border-top-color: var(--surface);
  border-radius: 50%;
  animation: spin 0.85s linear infinite;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-text {
  margin-top: 14px;
  color: var(--surface);
  font-size: 0.9em;
}

/* ── Placeholder ──────────────────────────────────────── */
.placeholder {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: var(--surface-2);
  pointer-events: none;
}
.placeholder-icon {
  font-size: 3.5em;
  margin-bottom: 12px;
  opacity: 0.45;
  display: block;
}
.placeholder p {
  font-size: 0.9em;
  opacity: 0.6;
}

/* ── Measure mode indicator ───────────────────────────── */
.mode-indicator {
  position: absolute;
  top: 14px;
  left: 14px;
  background: var(--accent);
  color: var(--surface);
  padding: 6px 13px;
  border-radius: var(--radius-sm);
  font-size: 0.82em;
  font-weight: 500;
  display: none;
  z-index: 50;
  letter-spacing: 0.02em;
}
.mode-indicator.active { display: block; }

/* ── Sidebar footer ───────────────────────────────────── */
.sidebar-footer {
  margin-top: auto;
  padding-top: 10px;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 0.78em;
  color: var(--muted);
}
.sidebar-footer a {
  color: var(--muted);
  text-decoration: none;
}
.sidebar-footer a:hover {
  color: var(--accent);
  text-decoration: underline;
}

/* ── Mobile ────────────────────────────────────────────── */
@media (max-width: 768px) {
  body { overflow: auto; }
  .app-container { flex-direction: column; }
  .sidebar {
    width: 100%;
    height: auto;
    max-height: 42vh;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }
  .viewer-container { height: 58vh; }
}