/* ==========================================================================
   PIXEL ART STUDIO — LUXURY INTERFACE SYSTEM
   Strict adherence to DESIGN.md specification
   Canvas: #000000 | Pure Monochrome | Wide-Tracked Typography | Pill CTAs
   Universal Mobile Responsiveness Architecture
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,300;0,400;0,500;0,600;1,400&family=IBM+Plex+Mono:ital,wght@0,300;0,400;0,500;1,400&family=Saira+Condensed:wght@300;400;500;600&display=swap');

:root {
  /* Colors from DESIGN.md */
  --color-primary: #ffffff;
  --color-ink: #ffffff;
  --color-body: #cccccc;
  --color-body-strong: #e6e6e6;
  --color-muted: #999999;
  --color-muted-soft: #666666;
  --color-hairline: #262626;
  --color-hairline-strong: #3a3a3a;
  --color-canvas: #000000;
  --color-surface-soft: #0d0d0d;
  --color-surface-card: #141414;
  --color-surface-elevated: #1f1f1f;
  --color-on-primary: #000000;
  --color-on-dark: #ffffff;
  --color-link: #c3d9f3;
  --color-warning: #d4a017;
  --color-success: #5fa657;

  /* Typography Stacks from DESIGN.md */
  --font-display: 'Saira Condensed', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: 'Cormorant Garamond', Garamond, "Times New Roman", serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, "SF Mono", monospace;

  /* Spacing */
  --space-xxs: 4px;
  --space-xs: 8px;
  --space-sm: 12px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  --space-xxl: 64px;
  --space-section: 120px;

  /* Binary Radii: Pill for buttons only, 0px for everything else */
  --radius-none: 0px;
  --radius-pill: 9999px;
  --radius-full: 9999px;

  --max-width: 1360px;
}

/* ==========================================================================
   Reset & Mobile Anti-Overflow Base
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  min-width: 0; /* Critical flex overflow prevention */
}

html {
  background-color: var(--color-canvas);
  color: var(--color-on-dark);
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  width: 100%;
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--color-canvas);
  color: var(--color-body);
  width: 100%;
  overflow-x: hidden;
  min-height: 100vh;
  position: relative;
}

img, canvas {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-none);
}

a {
  color: inherit;
  text-decoration: none;
  transition: opacity 0.2s ease, color 0.2s ease;
}

button, input, select {
  font-family: inherit;
  color: inherit;
  border: none;
  background: transparent;
  outline: none;
}

/* ==========================================================================
   Typography Classes (DESIGN.md tokens, weight 400 everywhere)
   ========================================================================== */
.display-xl {
  font-family: var(--font-display);
  font-size: clamp(28px, 5.5vw, 60px);
  font-weight: 400;
  line-height: 1.1;
  letter-spacing: clamp(2px, 0.4vw, 4px);
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.display-lg {
  font-family: var(--font-display);
  font-size: clamp(22px, 4vw, 44px);
  font-weight: 400;
  line-height: 1.15;
  letter-spacing: clamp(1.5px, 0.3vw, 3px);
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.display-md {
  font-family: var(--font-display);
  font-size: clamp(18px, 2.5vw, 30px);
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.display-sm {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 400;
  line-height: 1.3;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.wordmark {
  font-family: var(--font-display);
  font-size: clamp(12px, 2vw, 14px);
  font-weight: 400;
  line-height: 1;
  letter-spacing: clamp(3px, 0.6vw, 6px);
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.caption-uppercase {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  line-height: 1.4;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.caption-muted {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  line-height: 1.4;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-muted);
}

.body-md {
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.6;
  letter-spacing: 0;
  color: var(--color-body);
}

.body-strong {
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.6;
  letter-spacing: 0;
  color: var(--color-body-strong);
}

.body-sm {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 400;
  line-height: 1.5;
  letter-spacing: 0;
  color: var(--color-muted);
}

/* ==========================================================================
   Buttons (Signature Transparent Pill from DESIGN.md)
   ========================================================================== */
.button-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background-color: transparent;
  color: var(--color-on-dark);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: 2px;
  text-transform: uppercase;
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-pill);
  padding: 12px 24px;
  min-height: 44px;
  cursor: pointer;
  transition: background-color 0.25s ease, border-color 0.25s ease, transform 0.15s ease;
  text-align: center;
}

.button-primary:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: #ffffff;
  color: #ffffff;
}

.button-primary:active {
  transform: scale(0.98);
}

.button-primary.large {
  padding: 14px 28px;
  font-size: 13px;
  min-height: 48px;
}

.button-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: transparent;
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--radius-pill);
  padding: 11px 20px;
  min-height: 42px;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, background-color 0.2s ease;
  text-align: center;
}

.button-secondary:hover {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.06);
}

.button-link-reset {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-muted);
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.button-link-reset:hover {
  color: var(--color-on-dark);
}

/* ==========================================================================
   Global Drag & Drop Fullscreen Overlay
   ========================================================================== */
.global-drop-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.92);
  backdrop-filter: blur(8px);
  z-index: 9999;
  display: none;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  padding: 20px;
}

.global-drop-overlay.active {
  display: flex;
}

.drop-overlay-box {
  border: 2px dashed var(--color-primary);
  border-radius: var(--radius-none);
  padding: 40px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
  background-color: var(--color-surface-soft);
  max-width: 90%;
}

.drop-pulse-icon {
  font-size: 36px;
  animation: pulseIcon 1.2s ease-in-out infinite alternate;
}

@keyframes pulseIcon {
  from { transform: translateY(0); }
  to { transform: translateY(-8px); }
}

/* ==========================================================================
   Header Navigation (top-nav from DESIGN.md)
   ========================================================================== */
.top-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 56px;
  padding: 0 var(--space-xl);
  display: flex;
  align-items: center;
  justify-content: space-between;
  z-index: 1000;
  background-color: rgba(0, 0, 0, 0.9);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-hairline);
}

.top-nav-left, .top-nav-right {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  flex: 1;
}

.top-nav-center {
  flex: 0 0 auto;
}

.top-nav-right {
  justify-content: flex-end;
}

.nav-link {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-muted);
}

.nav-link:hover {
  color: var(--color-on-dark);
}

.privacy-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-success);
  border: 1px solid var(--color-hairline-strong);
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  white-space: nowrap;
}

/* ==========================================================================
   Hero & Persistent Top Upload Dock
   ========================================================================== */
.main-wrapper {
  padding-top: 76px;
  width: 100%;
  max-width: 100vw;
}

.tool-hero-header {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px var(--space-xl) var(--space-md);
  text-align: center;
}

.tool-hero-header .caption-muted {
  margin-bottom: var(--space-xs);
}

.tool-hero-header .display-xl {
  margin-bottom: var(--space-xs);
}

.tool-hero-header .hero-lead {
  max-width: 720px;
  margin: 0 auto;
  color: var(--color-body);
}

.error-banner {
  max-width: var(--max-width);
  margin: 0 auto var(--space-md);
  padding: 12px 20px;
  border: 1px solid var(--color-warning);
  background-color: rgba(212, 160, 23, 0.1);
  color: var(--color-warning);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 1px;
  display: none;
}

/* Persistent Upload Dock Section */
.upload-dock-section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl) var(--space-md);
  width: 100%;
}

.upload-dock-container {
  background-color: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  padding: var(--space-md) var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  width: 100%;
}

.upload-main-cta-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.upload-action-btn {
  background-color: rgba(255, 255, 255, 0.05);
}

.upload-drag-hint {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sample-chips-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  border-top: 1px solid var(--color-hairline);
  padding-top: var(--space-xs);
}

.sample-chip-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background-color: transparent;
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.sample-chip-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
}

.sample-chip-btn.active {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.08);
}

.sample-chip-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* ==========================================================================
   Tool Studio Workspace
   ========================================================================== */
.tool-workspace {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl) var(--space-xxl);
  display: grid;
  grid-template-columns: 1.25fr 0.95fr;
  gap: var(--space-xl);
  align-items: start;
  width: 100%;
}

/* Left Column: Canvas Preview Area */
.preview-stage-container {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  width: 100%;
}

.stage-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-hairline);
  padding-bottom: 8px;
  gap: var(--space-xs);
  flex-wrap: wrap;
  width: 100%;
}

.stage-top-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.file-name-badge {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1px;
  color: var(--color-muted);
  background: var(--color-surface-soft);
  padding: 2px 8px;
  border: 1px solid var(--color-hairline);
  max-width: 180px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.view-mode-tabs {
  display: flex;
  gap: 4px;
}

.view-mode-tab {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  border: 1px solid var(--color-hairline);
  padding: 5px 10px;
  border-radius: var(--radius-none);
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.view-mode-tab:hover {
  color: var(--color-on-dark);
}

.view-mode-tab.active {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.08);
}

/* Canvas & Coordinate Rulers Wrapper */
.canvas-ruler-wrapper {
  position: relative;
  background-color: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  width: 100%;
}

/* Top Horizontal Ruler */
.ruler-top {
  height: 20px;
  margin-left: 28px;
  background-color: #080808;
  border-bottom: 1px solid var(--color-hairline);
  position: relative;
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--color-muted-soft);
}

.ruler-tick-h {
  position: absolute;
  top: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  border-left: 1px solid var(--color-hairline-strong);
  padding-left: 3px;
  line-height: 1;
}

.ruler-viewport-row {
  display: flex;
  width: 100%;
  position: relative;
}

/* Left Vertical Ruler */
.ruler-left {
  width: 28px;
  background-color: #080808;
  border-right: 1px solid var(--color-hairline);
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--color-muted-soft);
}

.ruler-tick-v {
  position: absolute;
  left: 0;
  right: 0;
  display: flex;
  justify-content: center;
  border-top: 1px solid var(--color-hairline-strong);
  padding-top: 2px;
  line-height: 1;
}

/* Preview Viewport & Transparency Checkers */
.preview-viewport {
  position: relative;
  flex: 1;
  width: 100%;
  aspect-ratio: 4 / 3;
  max-height: 500px;
  background-color: #0c0c0c;
  background-image:
    linear-gradient(45deg, #141414 25%, transparent 25%),
    linear-gradient(-45deg, #141414 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #141414 75%),
    linear-gradient(-45deg, transparent 75%, #141414 75%);
  background-size: 16px 16px;
  background-position: 0 0, 0 8px, 8px -8px, -8px 0px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* Before / After Split Slider Layout */
.before-after-box {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.layer-converted, .layer-original {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
}

.layer-converted canvas, .layer-original img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

.layer-original {
  clip-path: polygon(0 0, 50% 0, 50% 100%, 0 100%);
  z-index: 5;
  transition: clip-path 0.04s ease-out;
}

.layer-original img {
  image-rendering: auto;
}

/* Split Handle Divider */
.split-divider-line {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 2px;
  background-color: var(--color-primary);
  z-index: 10;
  pointer-events: none;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.split-pill-badge {
  position: absolute;
  background-color: var(--color-canvas);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-pill);
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 1.5px;
  color: var(--color-on-dark);
  text-transform: uppercase;
  white-space: nowrap;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.8);
}

.split-range-input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: ew-resize;
  z-index: 20;
  touch-action: pan-y;
}

/* Alternate View Modes */
.before-after-box.mode-converted .layer-original,
.before-after-box.mode-converted .split-divider-line {
  display: none !important;
}

.before-after-box.mode-side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  padding: 6px;
}

.before-after-box.mode-side .layer-converted,
.before-after-box.mode-side .layer-original {
  position: relative;
  clip-path: none !important;
  border: 1px solid var(--color-hairline);
  background: rgba(0,0,0,0.5);
}

.before-after-box.mode-side .split-divider-line {
  display: none !important;
}

/* Processing Overlay Spinner */
.stage-loading-overlay {
  position: absolute;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  z-index: 50;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 2px;
  text-transform: uppercase;
}

.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid var(--color-hairline-strong);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Quick Canvas Sub-Toolbar */
.canvas-quick-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  padding: 8px var(--space-md);
  gap: var(--space-xs);
  flex-wrap: wrap;
  width: 100%;
}

.quick-tools-group {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.quick-tool-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  background: transparent;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.quick-tool-btn:hover {
  border-color: var(--color-hairline-strong);
  color: var(--color-on-dark);
}

.quick-tool-btn.active {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.08);
}

.quick-tool-icon {
  font-size: 12px;
}

.quick-telemetry-badge {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  color: var(--color-muted);
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.telemetry-sep {
  color: var(--color-hairline-strong);
}

/* Primary Export Actions Dock */
.export-actions-dock {
  background-color: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  padding: var(--space-md);
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  width: 100%;
}

.export-primary-wrap {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  width: 100%;
}

.main-download-btn {
  flex: 1.4;
}

.raw-sprite-btn {
  flex: 1;
}

.export-options-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-xs);
  padding-top: 4px;
}

.custom-checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
}

.custom-checkbox-label input {
  display: none;
}

.checkbox-custom {
  width: 14px;
  height: 14px;
  border: 1px solid var(--color-hairline-strong);
  background-color: transparent;
  display: inline-block;
  position: relative;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.custom-checkbox-label input:checked + .checkbox-custom {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
}

.custom-checkbox-label input:checked + .checkbox-custom::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: #000000;
  font-size: 10px;
  font-weight: bold;
}

/* ==========================================================================
   Right Column: Studio Controls Panel
   ========================================================================== */
.controls-panel {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  width: 100%;
}

/* Mobile Studio Controls Tabs Bar */
.mobile-tabs-bar {
  display: none;
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  padding: 3px;
  gap: 4px;
  width: 100%;
}

.mobile-tab-btn {
  flex: 1;
  padding: 9px 4px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  border-radius: var(--radius-none);
  text-align: center;
  cursor: pointer;
  white-space: nowrap;
}

.mobile-tab-btn.active {
  background-color: rgba(255, 255, 255, 0.08);
  color: var(--color-on-dark);
  border: 1px solid var(--color-hairline-strong);
}

/* Control Cards */
.control-card {
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  padding: var(--space-md) var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  width: 100%;
}

.card-header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 4px;
  gap: 8px;
  flex-wrap: wrap;
}

.control-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.pill-value-badge {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  color: var(--color-primary);
  border: 1px solid var(--color-hairline-strong);
  padding: 2px 8px;
  background: #000000;
  white-space: nowrap;
}

/* Range Slider with Tick Marks */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--color-hairline-strong);
  outline: none;
  border-radius: 0;
  margin: 10px 0 4px;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  border: 1px solid #000000;
  box-shadow: 0 0 6px rgba(255, 255, 255, 0.4);
}

.preset-slider-ticks {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 1px;
  color: var(--color-muted-soft);
  padding: 0 2px;
}

/* Preset Pill Buttons */
.preset-group {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  width: 100%;
}

.preset-btn {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  background-color: transparent;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  padding: 7px 12px;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.preset-btn:hover {
  border-color: var(--color-hairline-strong);
  color: var(--color-on-dark);
}

.preset-btn.active {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.08);
}

/* Segmented Pill Switches */
.segmented-control-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  width: 100%;
}

.segmented-pill-group {
  display: inline-flex;
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--radius-none);
  overflow: hidden;
  max-width: 100%;
}

.segmented-pill-group.full-width {
  display: flex;
  width: 100%;
}

.segmented-pill-btn {
  flex: 1;
  padding: 8px 10px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  background: transparent;
  cursor: pointer;
  text-align: center;
  transition: all 0.2s ease;
}

.segmented-pill-btn:hover {
  color: var(--color-on-dark);
}

.segmented-pill-btn.active {
  background-color: rgba(255, 255, 255, 0.12);
  color: var(--color-on-dark);
  font-weight: 500;
}

/* Retro Hardware Palettes Grid */
.retro-chips-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
  margin-top: 8px;
  width: 100%;
}

.retro-chip-btn {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 8px 10px;
  background-color: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  cursor: pointer;
  text-align: left;
  transition: all 0.2s ease;
}

.retro-chip-btn:hover {
  border-color: var(--color-hairline-strong);
  color: var(--color-on-dark);
}

.retro-chip-btn.active {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
  background-color: rgba(255, 255, 255, 0.05);
}

.chip-swatch-strip {
  width: 100%;
  height: 8px;
  border: 1px solid var(--color-hairline-strong);
}

.effect-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  flex-wrap: wrap;
  width: 100%;
}

.effect-label-wrap {
  display: flex;
  flex-direction: column;
}

/* ==========================================================================
   Materials & Live Color Palette Breakdown Table
   ========================================================================== */
.materials-card {
  padding: var(--space-md);
  width: 100%;
}

.copy-palette-btn {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--color-muted);
  border: 1px solid var(--color-hairline-strong);
  padding: 3px 8px;
  cursor: pointer;
}

.copy-palette-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-on-dark);
}

.materials-table-wrap {
  max-height: 340px;
  overflow-y: auto;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--color-hairline);
  background-color: var(--color-surface-soft);
  width: 100%;
}

.materials-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 11px;
}

.materials-table th {
  position: sticky;
  top: 0;
  background-color: #000000;
  padding: 8px 10px;
  border-bottom: 1px solid var(--color-hairline);
  letter-spacing: 1.5px;
  font-size: 9px;
  text-transform: uppercase;
  color: var(--color-muted);
  text-align: left;
  z-index: 2;
  white-space: nowrap;
}

.materials-table td {
  padding: 7px 10px;
  border-bottom: 1px solid var(--color-hairline);
  color: var(--color-body);
  vertical-align: middle;
}

.materials-table tr:hover td {
  background-color: rgba(255, 255, 255, 0.04);
}

.material-swatch-box {
  width: 14px;
  height: 14px;
  border: 1px solid var(--color-hairline-strong);
  display: inline-block;
  vertical-align: middle;
}

.material-name-col {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.material-color-name {
  color: var(--color-on-dark);
  font-size: 11px;
}

.material-hex-code {
  color: var(--color-muted-soft);
  font-size: 9px;
  letter-spacing: 1px;
}

.material-proportion-bar {
  display: inline-block;
  height: 4px;
  background-color: var(--color-hairline-strong);
  margin-top: 3px;
  border-radius: 2px;
}

/* ==========================================================================
   Editorial Content & SEO Guide Sections
   ========================================================================== */
.section {
  padding: var(--space-section) var(--space-xl);
  max-width: var(--max-width);
  margin: 0 auto;
  position: relative;
  width: 100%;
}

.section-header {
  margin-bottom: var(--space-xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  width: 100%;
}

.step-card {
  background-color: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.step-number {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 2px;
  color: var(--color-muted);
}

.step-title {
  font-family: var(--font-display);
  font-size: 22px;
  letter-spacing: 1.5px;
  color: var(--color-on-dark);
}

.editorial-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xl);
  width: 100%;
}

.editorial-card {
  background-color: var(--color-canvas);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-none);
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.editorial-card:hover {
  border-color: var(--color-hairline-strong);
}

/* FAQ Accordion */
.faq-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--color-hairline);
  width: 100%;
}

.faq-item {
  border-bottom: 1px solid var(--color-hairline);
}

.faq-question {
  width: 100%;
  text-align: left;
  padding: var(--space-lg) 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  gap: 12px;
}

.faq-question-text {
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: 1px;
  color: var(--color-on-dark);
}

.faq-icon {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--color-muted);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0.16, 1, 0.3, 1), padding 0.3s ease;
  padding: 0;
}

.faq-item.open .faq-answer {
  max-height: 300px;
  padding-bottom: var(--space-lg);
}

/* ==========================================================================
   Mobile Sticky Action Bar
   ========================================================================== */
.mobile-sticky-action-bar {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: rgba(0, 0, 0, 0.95);
  backdrop-filter: blur(14px);
  border-top: 1px solid var(--color-hairline-strong);
  padding: 8px var(--space-md) calc(8px + env(safe-area-inset-bottom));
  z-index: 2000;
  gap: var(--space-xs);
  width: 100%;
  max-width: 100vw;
}

.mobile-sticky-btn {
  flex: 1;
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  border-radius: var(--radius-pill);
  cursor: pointer;
  padding: 6px 12px;
  text-align: center;
}

.mobile-sticky-btn.primary {
  background-color: transparent;
  color: #ffffff;
  border: 1px solid #ffffff;
}

.mobile-sticky-btn.secondary {
  background-color: rgba(255, 255, 255, 0.08);
  color: var(--color-body);
  border: 1px solid var(--color-hairline-strong);
}

/* ==========================================================================
   Footer (DESIGN.md)
   ========================================================================== */
.footer {
  background-color: var(--color-canvas);
  border-top: 1px solid var(--color-hairline);
  padding: 70px var(--space-xl) 40px;
  width: 100%;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
  width: 100%;
}

.footer-nav-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-xl);
  width: 100%;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.footer-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links-list li a {
  font-family: var(--font-serif);
  font-size: 14px;
  color: var(--color-muted);
}

.footer-links-list li a:hover {
  color: var(--color-on-dark);
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
  border-top: 1px solid var(--color-hairline);
  padding-top: var(--space-lg);
}

.footer-wordmark {
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: 6px;
  text-transform: uppercase;
  color: var(--color-on-dark);
}

.footer-legal {
  font-family: var(--font-serif);
  font-size: 13px;
  color: var(--color-muted-soft);
  text-align: center;
}

/* ==========================================================================
   Comprehensive Device Responsiveness (Desktop, Tablet, Mobile)
   Smooth reflow across all zoom levels (50% to 200%) and device viewports
   ========================================================================== */

/* Tablet & Intermediate Viewports (769px to 1024px) */
@media (max-width: 1024px) and (min-width: 769px) {
  .top-nav {
    padding: 0 var(--space-md);
  }

  .top-nav-left {
    gap: var(--space-sm);
  }

  .top-nav-left a:nth-child(n+3) {
    display: none;
  }

  .tool-workspace {
    grid-template-columns: 1.15fr 0.85fr;
    gap: var(--space-md);
    padding: 0 var(--space-md) var(--space-xl);
  }

  /* Keep all controls visible on tablet; do NOT force mobile tabs */
  .mobile-tabs-bar {
    display: none !important;
  }

  .control-tab-content {
    display: block !important;
  }

  .control-card {
    padding: var(--space-md);
  }

  .preview-viewport {
    max-height: 440px;
  }

  .mobile-sticky-action-bar {
    display: none !important;
  }

  .steps-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
  }

  .editorial-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
  }

  .footer-nav-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-lg);
  }
}

/* Mobile Touch Devices (≤ 768px) */
@media (max-width: 768px) {
  .top-nav {
    padding: 0 var(--space-md);
    height: 50px;
  }

  .top-nav-left {
    display: none;
  }

  .wordmark {
    font-size: 13px;
    letter-spacing: 2px;
  }

  .privacy-badge span:last-child {
    display: none;
  }

  .privacy-badge {
    padding: 3px 6px;
    font-size: 9px;
  }

  /* Safe bottom padding for mobile sticky action bar */
  .main-wrapper {
    padding-top: 58px;
    padding-bottom: 96px !important;
  }

  /* Compact Hero on Mobile — immediate visual access to tool */
  .tool-hero-header {
    padding: 10px var(--space-md) 6px;
  }

  .tool-hero-header .caption-muted {
    font-size: 9px;
    letter-spacing: 1.5px;
    margin-bottom: 2px;
  }

  .tool-hero-header .display-xl {
    font-size: clamp(20px, 5.5vw, 26px);
    letter-spacing: 1.5px;
    margin-bottom: 4px;
    line-height: 1.15;
  }

  .tool-hero-header .hero-lead {
    font-size: 12px;
    line-height: 1.4;
    color: var(--color-muted);
  }

  /* Mobile Upload Dock */
  .upload-dock-section {
    padding: 6px var(--space-md) 10px;
  }

  .upload-dock-container {
    padding: 10px var(--space-sm);
    gap: 8px;
  }

  .upload-main-cta-box {
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
  }

  .upload-action-btn {
    width: 100%;
    padding: 11px 16px;
    font-size: 11px;
    letter-spacing: 1px;
    justify-content: center;
  }

  /* Hide desktop-only hints on touch mobile */
  .upload-drag-hint {
    display: none;
  }

  /* Horizontal swipeable sample artwork chips */
  .sample-chips-bar {
    display: flex;
    align-items: center;
    gap: 6px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding-top: 4px;
    padding-bottom: 2px;
    width: 100%;
  }

  .sample-chips-bar::-webkit-scrollbar {
    display: none;
  }

  .sample-chips-bar .caption-muted {
    font-size: 8px;
    letter-spacing: 1px;
    white-space: nowrap;
    flex-shrink: 0;
  }

  .sample-chip-btn {
    padding: 5px 10px;
    font-size: 9px;
    letter-spacing: 0.5px;
    white-space: nowrap;
    flex-shrink: 0;
  }

  /* Mobile Workspace Layout */
  .tool-workspace {
    grid-template-columns: 1fr;
    gap: var(--space-md);
    padding: 0 var(--space-md) var(--space-lg);
  }

  /* Canvas Preview Stage */
  .preview-stage-container {
    gap: 8px;
  }

  .stage-top-bar {
    padding-bottom: 6px;
    gap: 6px;
  }

  .stage-top-left {
    width: 100%;
    justify-content: space-between;
  }

  .file-name-badge {
    max-width: 180px;
    font-size: 9px;
  }

  .view-mode-tabs {
    width: 100%;
    display: flex;
  }

  .view-mode-tab {
    flex: 1;
    text-align: center;
    padding: 6px 2px;
    font-size: 9px;
    letter-spacing: 0.5px;
  }

  /* Canvas Viewport */
  .preview-viewport {
    height: 52vw;
    min-height: 240px;
    max-height: 330px;
    aspect-ratio: auto;
  }

  .ruler-top, .ruler-left {
    display: none;
  }

  /* Quick Toolbar on Mobile */
  .canvas-quick-toolbar {
    flex-direction: column;
    align-items: stretch;
    padding: 6px 10px;
    gap: 6px;
  }

  .quick-tools-group {
    width: 100%;
    display: flex;
  }

  .quick-tool-btn {
    flex: 1;
    text-align: center;
    justify-content: center;
    padding: 6px 4px;
    font-size: 9px;
  }

  .quick-telemetry-badge {
    justify-content: center;
    font-size: 8px;
    gap: 6px;
  }

  /* Inline Export Box inside Stage on Mobile */
  .export-actions-dock {
    padding-top: 4px;
  }

  .export-primary-wrap {
    flex-direction: column;
    gap: 6px;
  }

  .main-download-btn, .raw-sprite-btn {
    width: 100%;
    flex: none;
    font-size: 10px;
    padding: 10px 14px;
    letter-spacing: 1px;
  }

  .export-options-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    padding-top: 2px;
  }

  .custom-checkbox-label {
    font-size: 9px;
  }

  .button-link-reset {
    font-size: 9px;
  }

  /* Mobile Controls Panel with 3 Tabs */
  .controls-panel {
    gap: var(--space-sm);
  }

  .mobile-tabs-bar {
    display: flex;
    background-color: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    padding: 3px;
    gap: 3px;
    width: 100%;
  }

  .mobile-tab-btn {
    flex: 1;
    padding: 8px 2px;
    font-size: 9px;
    letter-spacing: 0.5px;
  }

  .control-tab-content {
    display: none;
  }

  .control-tab-content.active {
    display: block;
  }

  .control-card {
    padding: 12px var(--space-sm);
  }

  .card-header-row {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .control-label {
    font-size: 9px;
    letter-spacing: 1px;
  }

  .preset-group {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 4px;
  }

  .preset-btn {
    text-align: center;
    padding: 7px 4px;
    font-size: 9px;
  }

  .segmented-control-wrap {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .segmented-pill-group {
    width: 100%;
    display: flex;
  }

  .segmented-pill-btn {
    flex: 1;
    padding: 7px 3px;
    font-size: 8px;
    letter-spacing: 0.5px;
    text-align: center;
  }

  .effect-row {
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
  }

  .retro-chips-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 4px;
  }

  .retro-chip-btn {
    padding: 6px 8px;
    font-size: 9px;
  }

  /* Materials Breakdown Card on Mobile */
  .materials-card {
    padding: 10px var(--space-sm);
  }

  .materials-table th, .materials-table td {
    padding: 6px 4px;
    font-size: 9px;
  }

  .material-color-name {
    font-size: 9px;
  }

  .material-hex-code {
    font-size: 8px;
  }

  /* Persistent Bottom Mobile Sticky Action Bar */
  .mobile-sticky-action-bar {
    display: flex;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: rgba(0, 0, 0, 0.94);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid var(--color-hairline-strong);
    padding: 8px var(--space-md) calc(8px + env(safe-area-inset-bottom, 12px));
    z-index: 2000;
    gap: 8px;
    width: 100%;
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.8);
  }

  .mobile-sticky-btn {
    flex: 1;
    min-height: 40px;
    font-size: 9px;
    letter-spacing: 1px;
    padding: 6px 10px;
  }

  /* Editorial & Guide Sections on Mobile */
  .section {
    padding: 36px var(--space-md);
  }

  .section-header {
    margin-bottom: var(--space-lg);
  }

  .steps-grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .step-card {
    padding: var(--space-md);
  }

  .editorial-grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .editorial-card {
    padding: var(--space-md);
  }

  .faq-question {
    padding: 14px 0;
  }

  .faq-question-text {
    font-size: 16px;
  }

  /* Footer on Mobile */
  .footer {
    padding: 40px var(--space-md) 100px;
  }

  .footer-nav-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }
}

/* Extra Compact Phones (< 380px, e.g. iPhone SE, Galaxy Mini) */
@media (max-width: 380px) {
  .tool-hero-header .display-xl {
    font-size: 19px;
    letter-spacing: 1px;
  }

  .upload-action-btn {
    font-size: 10px;
    padding: 9px 12px;
  }

  .quick-telemetry-badge {
    font-size: 7px;
    gap: 4px;
  }

  .retro-chips-grid {
    grid-template-columns: 1fr;
  }
}