/* ==========================================================================
   Ultimate Color Picker - Dark Theme Stylesheet
   ========================================================================== */

/* ---------- Custom Properties ---------- */
:root {
  --bg-primary: #0f0f1a;
  --bg-secondary: #1a1a2e;
  --bg-tertiary: #16213e;
  --bg-panel: #1e1e3a;
  --bg-input: #252545;
  --border: #2a2a4a;
  --border-focus: #4a90d9;
  --text-primary: #e0e0f0;
  --text-secondary: #8888aa;
  --text-dim: #555577;
  --accent: #4a90d9;
  --accent-hover: #5aa0e9;
  --danger: #d94a4a;
  --success: #4ad94a;
  --warning: #d9c04a;
  --swatch-border: #3a3a5a;
  --scrollbar-thumb: #3a3a5a;
  --scrollbar-track: #1a1a2e;
  --toolbar-height: 40px;
  --bottom-bar-height: 100px;
  --panel-header-height: 30px;
  --transition-fast: 0.15s ease;
}

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  height: 100%;
}

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  font-size: 13px;
  line-height: 1.4;
  color: var(--text-primary);
  background: var(--bg-primary);
  display: grid;
  grid-template-rows: var(--toolbar-height) 1fr;
  grid-template-areas:
    "toolbar"
    "main";
  height: 100vh;
  margin: 0;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ---------- Custom Scrollbars ---------- */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: #4a4a6a;
}

::-webkit-scrollbar-corner {
  background: var(--scrollbar-track);
}

/* Firefox scrollbar */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
}

/* ---------- Typography ---------- */
h1, h2, h3, h4 {
  font-weight: 600;
  color: var(--text-primary);
}

h3 {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

/* ---------- Shared Button Styles ---------- */
button {
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
  font-family: inherit;
  font-size: inherit;
}

button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

.tool-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  height: 28px;
  padding: 0 10px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--text-primary);
  font-size: 12px;
  white-space: nowrap;
  transition: background var(--transition-fast), border-color var(--transition-fast);
}

.tool-btn:hover:not(:disabled) {
  background: var(--bg-tertiary);
  border-color: var(--accent);
}

.tool-btn:active:not(:disabled) {
  background: var(--bg-secondary);
}

.tool-btn:disabled {
  opacity: 0.35;
  cursor: default;
}

.tool-btn svg {
  flex-shrink: 0;
}

.small-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 20px;
  height: 20px;
  padding: 0 5px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 3px;
  color: var(--text-secondary);
  font-size: 12px;
  line-height: 1;
  transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.small-btn:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--accent);
}

.small-btn:active {
  background: var(--bg-secondary);
}

/* ---------- Shared Input Styles ---------- */
input[type="text"],
input[type="number"],
select {
  font-family: inherit;
  font-size: 12px;
  color: var(--text-primary);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 2px 6px;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

input[type="text"]:focus,
input[type="number"]:focus,
select:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 2px rgba(74, 144, 217, 0.2);
  outline: none;
}

.num-input {
  width: 60px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

select {
  cursor: pointer;
  padding-right: 18px;
}

/* ---------- Panel Header ---------- */
.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--panel-header-height);
  padding: 0 8px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.panel {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

/* ==========================================================================
   TOOLBAR
   ========================================================================== */
#toolbar {
  grid-area: toolbar;
  display: flex;
  align-items: center;
  height: var(--toolbar-height);
  padding: 0 10px;
  background: linear-gradient(180deg, #1e1e3a 0%, #16213e 100%);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

.toolbar-left {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.app-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--accent);
  margin-right: 12px;
  letter-spacing: -0.3px;
}

/* ==========================================================================
   MAIN CONTENT - Golden Layout Container
   ========================================================================== */
#main-content {
  grid-area: main;
  overflow: auto;
}

/* Panel containers stretch their content to fill the GridStack cell */
#panel-picker, #panel-3dview {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
  overflow-y: auto;
}

#panel-3dview > #view3d-container {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
}


/* ---------- Left Panel: Slider Groups ---------- */

#slider-groups {
  flex: 1;
  overflow-y: auto;
  padding: 4px;
  /* Flow into multiple columns when the panel is wide enough */
  display: flex;
  flex-wrap: wrap;
  align-content: flex-start;
  gap: 6px;
}

/* Slider group */
.slider-group {
  /* Each group is a fixed-width card that wraps into columns */
  width: 200px;
  min-width: 160px;
  flex-grow: 0;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg-secondary);
}

.slider-group-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 4px 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  border-bottom: 1px solid var(--border);
  background: rgba(74, 144, 217, 0.05);
}

.slider-group-header .remove-btn {
  width: 16px;
  height: 16px;
  font-size: 11px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  background: transparent;
  border: none;
  border-radius: 2px;
  cursor: pointer;
  transition: color var(--transition-fast), background var(--transition-fast);
}

.slider-group-header .remove-btn:hover {
  color: var(--danger);
  background: rgba(217, 74, 74, 0.15);
}

/* Slider rows directly inside group (no body wrapper) */
.slider-group > .slider-row {
  padding: 0 8px;
}

.slider-group > .slider-row:first-of-type {
  padding-top: 6px;
}

.slider-group > .slider-row:last-of-type {
  padding-bottom: 6px;
}

/* Individual slider row */
.slider-row {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 4px;
}

.slider-row:last-child {
  margin-bottom: 0;
}

.slider-label {
  width: 58px;
  flex-shrink: 0;
  font-size: 10px;
  font-weight: 600;
  color: var(--text-secondary);
  text-align: right;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.slider-canvas-wrap {
  flex: 1;
  min-width: 60px;
  position: relative;
  height: 20px;
}

.slider-canvas-wrap canvas {
  width: 100%;
  height: 20px;
  border-radius: 10px;
  cursor: pointer;
  display: block;
}

/* Slider thumb - rendered by JS, styled for reference */
.slider-thumb-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
}

.slider-thumb {
  position: absolute;
  top: 50%;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid #1a1a2e;
  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.3), 0 1px 3px rgba(0, 0, 0, 0.4);
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 2;
}

.slider-row .num-input {
  width: 56px;
  height: 20px;
  font-size: 11px;
  padding: 0 4px;
}

/* Quick value buttons — sits on own row below the slider, aligned with canvas */
.slider-quick-btns {
  display: flex;
  gap: 2px;
  flex-wrap: wrap;
  padding: 1px 56px 2px 46px;  /* left = label(40) + gap(6), right = input(56) */
}

.slider-quick-btn {
  min-width: 18px;
  height: 16px;
  padding: 0 3px;
  font-size: 9px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-dim);
  cursor: pointer;
  line-height: 1;
  transition: color var(--transition-fast), background var(--transition-fast);
}

.slider-quick-btn:hover {
  color: var(--text-primary);
  background: var(--bg-tertiary);
  border-color: var(--accent);
}

/* Gamut warning indicator on slider */
.slider-canvas-wrap.out-of-gamut canvas {
  opacity: 0.6;
}

.slider-canvas-wrap.imaginary canvas {
  box-shadow: inset 0 0 0 1px var(--danger);
}

/* Crosshatch overlay for undisplayable regions */
.gamut-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
  border-radius: 10px;
  overflow: hidden;
}

.gamut-overlay.undisplayable {
  background: repeating-linear-gradient(
    45deg,
    transparent,
    transparent 2px,
    rgba(0, 0, 0, 0.25) 2px,
    rgba(0, 0, 0, 0.25) 4px
  );
  opacity: 0.5;
}

.gamut-overlay.imaginary {
  background: rgba(217, 74, 74, 0.15);
}

/* ==========================================================================
   CENTER: 2D Picker Section
   ========================================================================== */

/* Picker controls bar */
#picker-controls {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 2px 4px 4px;
  flex-wrap: wrap;
  flex-shrink: 0;
  font-size: 11px;
}

#picker-controls select {
  height: 20px;
  font-size: 10px;
  max-width: 80px;
}

.picker-axis-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.picker-axis-controls label {
  display: flex;
  align-items: center;
  gap: 3px;
  font-size: 11px;
  color: var(--text-secondary);
}

.picker-axis-buttons {
  display: flex;
  gap: 3px;
}

.picker-axis-buttons .small-btn {
  font-size: 11px;
  height: 20px;
  padding: 0 5px;
}

/* Picker area layout — fills available space but never crushes below usable size */
#picker-area {
  flex: 1;
  min-height: 200px;
  overflow: hidden;
  display: flex;
  gap: 4px;
}

/* Y-axis slider (left of picker) */
.axis-slider-y {
  width: 24px;
  flex-shrink: 0;
  align-self: flex-start;  /* don't stretch to full column height */
  cursor: pointer;
  border-radius: 4px;
  border: 1px solid var(--border);
}

/* Right side of picker area: canvas + X slider + excluded slider */
#picker-right-col {
  flex: 1;
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* Picker canvas container — sized by JS to be square */
#picker-canvas-container {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-secondary);
}

#picker-canvas {
  /* Fill the container completely — ResizeObserver syncs internal resolution */
  width: 100%;
  height: 100%;
  display: block;
  cursor: crosshair;
}

/* Crosshair */
.crosshair {
  position: absolute;
  pointer-events: none;
  width: 22px;
  height: 22px;
  transform: translate(-50%, -50%);
  z-index: 10;
}

.crosshair::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border: 2px solid #fff;
  border-radius: 50%;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.5);
}

.crosshair::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 2px;
  height: 2px;
  background: #fff;
  border-radius: 50%;
  transform: translate(-50%, -50%);
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.5);
}

/* X-axis slider (below picker) */
.axis-slider-x {
  width: 100%;  /* matches the canvas container above it */
  height: 24px;
  flex-shrink: 0;
  cursor: pointer;
  border-radius: 4px;
  border: 1px solid var(--border);
}

/* Excluded dimension slider — inside picker-right-col, same width as canvas */
#excluded-slider-container {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 4px 4px;
  flex-shrink: 0;
}

#excluded-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-secondary);
  width: 50px;
  text-align: right;
  flex-shrink: 0;
}

#excluded-slider {
  flex: 1;
  height: 24px;
  border-radius: 4px;
  border: 1px solid var(--border);
  cursor: pointer;
}

#excluded-slider-container .num-input {
  width: 56px;
  height: 22px;
  font-size: 11px;
}

/* ---------- Gradient Tools ---------- */
#gradient-tools {
  flex-shrink: 0;
  padding: 0;
}

.gradient-section {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 8px;
  margin-top: 6px;
}

.gradient-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
}

.gradient-header .close-btn {
  width: 18px;
  height: 18px;
  font-size: 14px;
  padding: 0;
}

.gradient-endpoints {
  display: flex;
  align-items: center;
  gap: 6px;
}

.gradient-swatch {
  width: 30px;
  height: 30px;
  border: 2px solid var(--swatch-border);
  border-radius: 4px;
  cursor: pointer;
  flex-shrink: 0;
  transition: border-color var(--transition-fast);
}

.gradient-swatch:hover {
  border-color: var(--accent);
}

#gradient-bar {
  flex: 1;
  height: 30px;
  border-radius: 4px;
  border: 1px solid var(--border);
  cursor: pointer;
}

#triangle-canvas {
  display: block;
  margin: 0 auto;
  cursor: crosshair;
}

.triangle-swatches {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 6px;
}

/* ==========================================================================
   RIGHT PANEL: Info & Accuracy
   ========================================================================== */

#info-panel .panel-header select {
  max-width: 120px;
  height: 20px;
  font-size: 11px;
}

#info-content {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}

.info-section {
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.info-section:last-child {
  border-bottom: none;
}

#info-description {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Equations - monospace */
#info-equations-content {
  font-family: 'Cascadia Code', 'Consolas', 'Fira Code', monospace;
  font-size: 11px;
  color: var(--text-primary);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 6px 8px;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-all;
}

/* Gamut info */
#info-gamut-content {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Accuracy meters */
#accuracy-meters {
  margin-bottom: 8px;
}

.meter-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.meter-row {
  display: flex;
  align-items: center;
  gap: 6px;
}

.meter-label {
  width: 30px;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-secondary);
  text-align: right;
  flex-shrink: 0;
}

.meter-bar-bg {
  width: 150px;
  height: 10px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 5px;
  overflow: hidden;
  flex-shrink: 0;
}

.meter-bar-fill {
  height: 100%;
  border-radius: 5px;
  transition: width 0.2s ease;
}

.meter-bar-fill.accurate {
  background: var(--success);
}

.meter-bar-fill.moderate {
  background: var(--warning);
}

.meter-bar-fill.inaccurate {
  background: var(--danger);
}

.meter-value {
  font-size: 10px;
  font-variant-numeric: tabular-nums;
  color: var(--text-dim);
  width: 40px;
}

.meter-controls {
  display: flex;
  gap: 10px;
  font-size: 11px;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.meter-controls label {
  display: flex;
  align-items: center;
  gap: 3px;
  cursor: pointer;
}

.meter-controls input[type="radio"] {
  accent-color: var(--accent);
}

.delta-e-display {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 4px 0;
}

/* ---------- 3D Color Space Viewer ---------- */
.view3d-section {
  margin-bottom: 0;
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}

.view3d-header {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 6px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.view3d-header select {
  max-width: 120px;
  height: 20px;
  font-size: 11px;
}

.view3d-canvas-wrap {
  position: relative;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
  background: #000;
  flex: 1;
  min-height: 0;
}

.view3d-canvas {
  display: block;
  max-width: 100%;
  max-height: 100%;
  cursor: grab;
}

.view3d-canvas:active {
  cursor: grabbing;
}

/* ---------- Color Harmony ---------- */
.harmony-section {
  margin-bottom: 4px;
}

.harmony-header {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 6px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.harmony-header select {
  max-width: 140px;
  height: 20px;
  font-size: 11px;
}

.harmony-swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 6px;
}

/* ==========================================================================
   BOTTOM BAR
   ========================================================================== */
#bottom-bar {
  grid-area: bottom;
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: var(--bottom-bar-height);
  padding: 8px 12px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  overflow: hidden;
}

/* Current swatch */
#current-swatch-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  flex-shrink: 0;
}

#current-swatch {
  width: 60px;
  height: 60px;
  border: 2px solid var(--swatch-border);
  border-radius: 4px;
  position: relative;
  overflow: hidden;
  cursor: grab;
}

#current-swatch:active {
  cursor: grabbing;
}

.swatch-half {
  position: absolute;
  width: 100%;
  height: 100%;
}

#swatch-actual {
  clip-path: polygon(0 0, 100% 0, 0 100%);
  background: #4A90D9;
}

#swatch-intended {
  clip-path: polygon(100% 0, 100% 100%, 0 100%);
  background: #4A90D9;
}

/* Hex display */
#hex-display {
  display: flex;
  align-items: center;
  gap: 3px;
}

.hex-input {
  width: 78px;
  height: 22px;
  font-family: 'Cascadia Code', 'Consolas', monospace;
  font-size: 12px;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

#hex-display .small-btn {
  width: 22px;
  height: 22px;
  padding: 0;
}

#hex-display .small-btn svg {
  display: block;
}

/* Color output panel */
#color-output {
  display: flex;
  flex-direction: column;
  gap: 3px;
  flex-shrink: 0;
  font-size: 11px;
  min-width: 0;
}

#css-formats {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
}

.css-format {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  padding: 1px 5px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 3px;
  cursor: pointer;
  font-family: 'Cascadia Code', 'Consolas', monospace;
  font-size: 10px;
  color: var(--text-primary);
  transition: border-color var(--transition-fast);
  white-space: nowrap;
}

.css-format:hover {
  border-color: var(--accent);
}

.css-format.copied {
  border-color: var(--success);
  background: rgba(74, 217, 74, 0.1);
}

.css-format-label {
  color: var(--text-dim);
  font-size: 9px;
  font-weight: 600;
}

#contrast-info {
  display: flex;
  gap: 6px;
}

.contrast-item {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  font-size: 10px;
  color: var(--text-secondary);
}

.contrast-sample {
  display: inline-block;
  padding: 0 3px;
  border-radius: 2px;
  font-size: 10px;
  font-weight: 700;
  line-height: 16px;
  border: 1px solid var(--border);
}

.contrast-level {
  font-weight: 700;
  font-size: 9px;
  padding: 0 3px;
  border-radius: 2px;
}

.contrast-level.pass {
  color: var(--success);
}

.contrast-level.fail {
  color: var(--danger);
}

#nearest-name {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nearest-swatch {
  width: 12px;
  height: 12px;
  border-radius: 2px;
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.nearest-label {
  font-size: 10px;
  color: var(--text-secondary);
}

/* Correlated color temperature */
#color-temp {
  font-size: 10px;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  gap: 4px;
}

.cct-warm { color: #f0a040; }
.cct-neutral { color: #e0e0e0; }
.cct-cool { color: #60a0f0; }

/* Color vision deficiency simulation */
#cvd-sim {
  display: flex;
  gap: 6px;
  align-items: center;
  flex-wrap: wrap;
}

.cvd-item {
  display: inline-flex;
  align-items: center;
  gap: 3px;
}

.cvd-swatch {
  width: 14px;
  height: 14px;
  border-radius: 2px;
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.cvd-label {
  font-size: 9px;
  color: var(--text-dim);
}

/* Color history */
#color-history-container {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex-shrink: 0;
}

#color-history-container .panel-header {
  height: 18px;
  padding: 0 4px;
  border-bottom: none;
  font-size: 10px;
}

#color-history-strip {
  display: flex;
  gap: 1px;
  overflow-x: auto;
  padding-bottom: 2px;
}

.history-swatch {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  border: 1px solid var(--swatch-border);
  border-radius: 2px;
  cursor: pointer;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.history-swatch:hover {
  border-color: var(--accent);
  transform: scale(1.2);
}

/* Quick color buttons */
#quick-colors {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  flex-shrink: 0;
}

.quick-btn {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 2px solid var(--swatch-border);
  cursor: pointer;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.quick-btn:hover {
  border-color: var(--accent);
  transform: scale(1.15);
}

.quick-btn:active {
  transform: scale(0.95);
}

/* Saved colors */
#saved-colors-container {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

#saved-colors-container .panel-header {
  height: 20px;
  padding: 0 4px;
  border-bottom: none;
}

#saved-colors-strip {
  display: flex;
  gap: 2px;
  overflow-x: auto;
  padding-bottom: 4px;
}

.saved-swatch {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  border: 2px solid var(--swatch-border);
  border-radius: 4px;
  cursor: pointer;
  position: relative;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.saved-swatch:hover {
  border-color: var(--accent);
  transform: scale(1.08);
}

.saved-swatch .delete-badge {
  position: absolute;
  top: -4px;
  right: -4px;
  width: 14px;
  height: 14px;
  background: var(--danger);
  color: #fff;
  border-radius: 50%;
  font-size: 10px;
  display: none;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

.saved-swatch:hover .delete-badge {
  display: flex;
}

/* Collections */
#collections-container {
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex: 1;
  min-width: 0;
}

#collection-select {
  height: 22px;
  font-size: 11px;
  width: 100%;
}

#collection-colors {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  overflow-y: auto;
  max-height: 68px;
  padding-bottom: 4px;
}

.collection-swatch {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  border: 1px solid var(--swatch-border);
  border-radius: 2px;
  cursor: pointer;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.collection-swatch:hover {
  border-color: var(--accent);
  transform: scale(1.2);
}

/* ==========================================================================
   DIALOG: Color Space Picker
   ========================================================================== */
dialog {
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-panel);
  color: var(--text-primary);
  padding: 0;
  min-width: 360px;
  max-width: 500px;
  max-height: 70vh;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

dialog::backdrop {
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
}

dialog h2 {
  font-size: 15px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
}

#space-picker-list {
  padding: 8px;
  overflow-y: auto;
  max-height: calc(70vh - 100px);
}

.space-picker-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 10px;
  border-radius: 4px;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.space-picker-item:hover {
  background: var(--bg-tertiary);
}

.space-picker-item.active {
  background: rgba(74, 144, 217, 0.1);
  border: 1px solid rgba(74, 144, 217, 0.3);
}

.space-picker-item .space-name {
  font-weight: 600;
  font-size: 13px;
}

.space-picker-item .space-desc {
  font-size: 11px;
  color: var(--text-dim);
  margin-top: 2px;
}

.space-picker-item .space-toggle {
  width: 36px;
  height: 20px;
  border-radius: 10px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  position: relative;
  transition: background var(--transition-fast);
  flex-shrink: 0;
}

.space-picker-item.active .space-toggle {
  background: var(--accent);
  border-color: var(--accent);
}

.space-picker-item .space-toggle::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #fff;
  transition: transform var(--transition-fast);
}

.space-picker-item.active .space-toggle::after {
  transform: translateX(16px);
}

.dialog-buttons {
  display: flex;
  justify-content: flex-end;
  padding: 10px 16px;
  border-top: 1px solid var(--border);
}

/* ==========================================================================
   PALETTE EDITOR
   ========================================================================== */
#palette-editor-panel {
  position: fixed;
  bottom: var(--bottom-bar-height);
  left: 0;
  right: 0;
  max-height: 50vh;
  background: var(--bg-panel);
  border-top: 1px solid var(--border);
  z-index: 50;
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.3);
  display: flex;
  flex-direction: column;
}

#palette-editor-panel .panel-header {
  padding: 0 12px;
  flex-shrink: 0;
}

#palette-content {
  padding: 8px 12px;
  overflow-y: auto;
  flex: 1;
  min-height: 0;
}

#palette-top-row {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 8px;
}

#palette-canvas {
  flex: 1;
  min-width: 200px;
  height: 60px;
  display: block;
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
}

#palette-image-container {
  position: relative;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg-input);
  overflow: hidden;
  display: none;  /* hidden until an image is loaded */
}

#palette-image-container.has-image {
  display: block;
}

#btn-close-preview-image {
  position: absolute;
  top: 4px;
  right: 4px;
  z-index: 5;
  width: 20px;
  height: 20px;
  font-size: 14px;
  opacity: 0.6;
}

#btn-close-preview-image:hover {
  opacity: 1;
}

#palette-image-canvas {
  display: block;
  max-width: 100%;
  max-height: 40vh;
  image-rendering: pixelated;  /* preserve pixel art crispness */
}

#palette-image-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: var(--text-dim);
  padding: 8px;
  text-align: center;
}

#palette-controls {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

#palette-controls .tool-btn {
  height: 24px;
  font-size: 11px;
  padding: 0 8px;
}

.palette-rotate-label,
.picker-rot-label {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 11px;
  color: var(--text-secondary);
}

#palette-rotation,
#palette-animate-speed {
  width: 80px;
  accent-color: var(--accent);
}

.palette-separator {
  display: inline-block;
  width: 1px;
  height: 16px;
  background: var(--border);
  margin: 0 2px;
  vertical-align: middle;
}

/* ==========================================================================
   UTILITY & STATE CLASSES
   ========================================================================== */

/* Disabled state overlay */
.disabled-overlay {
  position: relative;
  pointer-events: none;
}

.disabled-overlay::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(15, 15, 26, 0.5);
  border-radius: inherit;
}

/* Drag active */
.dragging {
  cursor: grabbing !important;
  user-select: none;
}

/* Loading shimmer */
.loading-shimmer {
  background: linear-gradient(
    90deg,
    var(--bg-input) 25%,
    var(--bg-tertiary) 50%,
    var(--bg-input) 75%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Fade in animation */
.fade-in {
  animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Tooltip */
[title] {
  position: relative;
}

/* Focus-visible for keyboard nav */
*:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */
@media (max-width: 700px) {
  /* Bottom bar: wrap */
  #bottom-bar {
    flex-wrap: wrap;
    min-height: auto;
    padding: 6px 8px;
    gap: 8px;
  }

  #saved-colors-container {
    order: 10;
    width: 100%;
  }

  #collections-container {
    max-width: none;
    flex: 1;
  }
}

/* Even narrower screens */
@media (max-width: 600px) {
  :root {
    --toolbar-height: 36px;
    --bottom-bar-height: auto;
  }

  .app-title {
    font-size: 13px;
    margin-right: 6px;
  }

  #toolbar .tool-btn span,
  #btn-eyedropper {
    font-size: 11px;
  }

  #current-swatch {
    width: 48px;
    height: 48px;
  }

  .quick-btn {
    width: 20px;
    height: 20px;
  }

  .saved-swatch {
    width: 30px;
    height: 30px;
  }

  #picker-controls {
    gap: 4px;
  }

  .picker-axis-buttons {
    display: none;
  }
}

/* High contrast preference */
@media (prefers-contrast: high) {
  :root {
    --border: #4a4a7a;
    --text-primary: #f0f0ff;
    --text-secondary: #aaaacc;
  }

  .tool-btn,
  .small-btn {
    border-width: 2px;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}