/* Kid Color Play - Styling System */
:root {
  --bg-gradient: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
  --panel-bg: rgba(255, 255, 255, 0.85);
  --panel-border: rgba(255, 255, 255, 0.6);
  --primary-color: #ff6b6b;
  --primary-hover: #ff5252;
  --secondary-color: #4ecdc4;
  --accent-yellow: #ffe66d;
  --text-dark: #2d3436;
  --text-muted: #636e72;
  --shadow-soft: 0 8px 32px 0 rgba(31, 38, 135, 0.12);
  --shadow-button: 0 4px 12px rgba(0, 0, 0, 0.08);
  --radius-xl: 24px;
  --radius-lg: 16px;
  --radius-md: 12px;
  --font-family: 'Fredoka', 'Gaegu', 'Noto Sans KR', sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: var(--font-family);
  background: var(--bg-gradient);
  color: var(--text-dark);
  touch-action: none;
}

/* App Container */
.app-container {
  display: flex;
  flex-direction: column;
  width: 100vw;
  height: 100vh;
  height: 100dvh;
  position: relative;
  overflow: hidden;
}

/* Header */
.app-header {
  height: 60px;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--panel-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 2px solid var(--panel-border);
  box-shadow: var(--shadow-soft);
  z-index: 10;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  flex-shrink: 0;
}

.logo-icon {
  font-size: 1.6rem;
  animation: bounce 2s infinite ease-in-out;
  flex-shrink: 0;
}

.app-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: -0.5px;
  white-space: nowrap;
}

.app-title .highlight {
  color: var(--primary-color);
}

.top-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

/* Buttons */
.btn, .icon-btn, .tool-btn {
  border: none;
  outline: none;
  cursor: pointer;
  font-family: inherit;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-button);
}

.btn:active, .icon-btn:active, .tool-btn:active {
  transform: scale(0.92);
}

.icon-btn {
  width: 44px;
  height: 44px;
  background: white;
  color: var(--text-dark);
  border-radius: 50%;
}

.icon-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
}

.icon-btn:not(:disabled):hover {
  background: #f1f2f6;
  transform: translateY(-2px);
}

.danger-btn {
  color: #ff4757;
}

.danger-btn:hover {
  background: #ffe0e3 !important;
}

.primary-btn {
  background: linear-gradient(135deg, var(--primary-color), #ff8e8e);
  color: white;
  padding: 8px 18px;
  font-size: 0.95rem;
  border-radius: 20px;
  gap: 6px;
}

.primary-btn:hover {
  background: linear-gradient(135deg, var(--primary-hover), var(--primary-color));
  box-shadow: 0 6px 16px rgba(255, 107, 107, 0.35);
}

.secondary-btn {
  background: #f1f2f6;
  color: var(--text-dark);
  padding: 8px 16px;
  border-radius: 20px;
}

/* Main Content Area */
.main-content {
  flex: 1;
  display: flex;
  position: relative;
  overflow: hidden;
}

/* Sidebar Tools (Desktop/Tablet default: Left side) */
.sidebar {
  width: 220px;
  background: var(--panel-bg);
  backdrop-filter: blur(10px);
  border-right: 2px solid var(--panel-border);
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  z-index: 5;
  overflow-y: auto;
}

.tool-section {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.section-label {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding-left: 4px;
}

.tool-group {
  display: flex;
  gap: 8px;
}

.flex-col {
  flex-direction: column;
}

.grid-tools {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.tool-btn {
  padding: 10px;
  background: white;
  border: 2px solid transparent;
  color: var(--text-dark);
  font-size: 0.85rem;
  flex-direction: column;
  gap: 4px;
  border-radius: var(--radius-md);
}

.tool-btn:hover {
  background: #f8f9fa;
  transform: translateY(-2px);
}

.tool-btn.active {
  border-color: var(--primary-color);
  background: #fff0f0;
  color: var(--primary-color);
  box-shadow: 0 4px 12px rgba(255, 107, 107, 0.2);
}

.special-btn {
  background: linear-gradient(135deg, #a1c4fd 0%, #c2e9fb 100%);
  color: #1e3799;
}

.file-upload-label {
  cursor: pointer;
  background: linear-gradient(135deg, #f6d365 0%, #fda085 100%);
  color: #6f1d00;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.tool-badge {
  font-size: 1.4rem;
}

/* Size Slider Section */
.size-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  background: white;
  padding: 10px;
  border-radius: var(--radius-md);
}

.size-preview {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.size-preview::after {
  content: '';
  display: block;
  border-radius: 50%;
  background: var(--text-dark);
  transition: width 0.1s, height 0.1s;
}

.custom-slider {
  flex: 1;
  accent-color: var(--primary-color);
  cursor: pointer;
  height: 6px;
}

/* Canvas Viewport */
.canvas-viewport {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  overflow: hidden;
}

#bg-canvas, #draw-canvas {
  position: absolute;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  touch-action: none;
}

#bg-canvas {
  background: white;
  z-index: 1;
}

#draw-canvas {
  z-index: 2;
  cursor: crosshair;
  mix-blend-mode: multiply;
}

.opacity-icon {
  font-size: 1.1rem;
}

.brush-cursor {
  position: fixed;
  pointer-events: none;
  border: 2px solid rgba(0, 0, 0, 0.7);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  z-index: 999;
  transition: width 0.05s, height 0.05s;
  box-shadow: 0 0 4px rgba(255, 255, 255, 0.8);
}

.brush-cursor.hidden {
  display: none;
}

/* Footer / Palette */
.app-footer {
  height: 80px;
  background: var(--panel-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 2px solid var(--panel-border);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 16px;
  z-index: 10;
}

.palette-container {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 100%;
  overflow-x: auto;
  padding: 6px 4px;
}

.palette-scroll {
  display: flex;
  gap: 10px;
  padding: 4px;
  overflow-x: auto;
  scrollbar-width: none;
}

.palette-scroll::-webkit-scrollbar {
  display: none;
}

.color-btn {
  width: 44px;
  height: 44px;
  min-width: 44px;
  border-radius: 50%;
  border: 3px solid white;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
  cursor: pointer;
  transition: transform 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.2s;
  position: relative;
}

.color-btn:hover {
  transform: scale(1.15);
}

.color-btn.selected {
  transform: scale(1.22);
  border-color: #2d3436;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
  z-index: 2;
}

.color-btn.selected::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  font-weight: bold;
  font-size: 1rem;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.8);
}

.custom-color-btn {
  background: conic-gradient(red, yellow, lime, aqua, blue, magenta, red);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.custom-color-btn input[type="color"] {
  position: absolute;
  opacity: 0;
  width: 100%;
  height: 100%;
  cursor: pointer;
}

.custom-color-icon {
  font-size: 1.2rem;
  pointer-events: none;
}

/* Modals */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  opacity: 1;
  transition: opacity 0.3s ease;
}

.modal-overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.modal-card {
  background: white;
  width: 90%;
  max-width: 620px;
  max-height: 85vh;
  border-radius: var(--radius-xl);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  animation: popUp 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.modal-header {
  padding: 18px 24px;
  background: #f8f9fa;
  border-bottom: 1px solid #eee;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-header h2 {
  font-size: 1.25rem;
  color: var(--text-dark);
}

.modal-close-btn {
  background: none;
  border: none;
  font-size: 1.8rem;
  cursor: pointer;
  color: var(--text-muted);
}

.modal-body {
  padding: 24px;
  overflow-y: auto;
}

/* Template Grid */
.template-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 16px;
}

.template-card {
  border: 3px solid #eee;
  border-radius: var(--radius-md);
  padding: 10px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
  background: #fafafa;
}

.template-card:hover {
  border-color: var(--primary-color);
  transform: translateY(-4px);
  box-shadow: var(--shadow-button);
  background: #fff5f5;
}

.template-card img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 8px;
  background: white;
}

.template-card span {
  font-size: 0.85rem;
  font-weight: 700;
}

.blank-card {
  justify-content: center;
  min-height: 150px;
}

.blank-icon {
  font-size: 3rem;
}

/* Filter Modal */
.filter-preview-body {
  display: flex;
  flex-direction: column;
  gap: 16px;
  align-items: center;
}

.filter-canvas-wrapper {
  max-width: 100%;
  max-height: 300px;
  overflow: hidden;
  border-radius: var(--radius-md);
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.1);
  background: #f0f0f0;
}

.filter-canvas-wrapper canvas {
  max-width: 100%;
  max-height: 300px;
  display: block;
}

.filter-controls {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.filter-controls label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-weight: 600;
  font-size: 0.9rem;
}

.filter-actions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

/* Animations */
@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

@keyframes popUp {
  0% { transform: scale(0.8); opacity: 0; }
  100% { transform: scale(1); opacity: 1; }
}

/* Responsive Layout for Mobile / Vertical Mode */
@media (max-width: 768px) {
  .app-header {
    height: 54px;
    padding: 0 10px;
    gap: 6px;
  }

  .logo-area {
    gap: 4px;
  }

  .logo-icon {
    font-size: 1.3rem;
  }

  .app-title {
    font-size: 1.05rem;
  }

  .icon-btn {
    width: 36px;
    height: 36px;
  }

  .top-actions {
    gap: 4px;
  }

  .main-content {
    flex-direction: column-reverse; /* Put sidebar at the bottom for easy touch access */
  }

  .sidebar {
    width: 100%;
    height: auto;
    border-right: none;
    border-top: 2px solid var(--panel-border);
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    padding: 10px 14px;
    gap: 12px;
    overflow-x: auto;
  }

  .tool-section {
    flex-direction: row;
    align-items: center;
    gap: 8px;
  }

  .section-label {
    display: none; /* Hide text label on mobile to save space */
  }

  .grid-tools {
    display: flex;
    flex-direction: row;
  }

  .tool-btn {
    padding: 6px 10px;
    flex-direction: row;
    font-size: 0.8rem;
  }

  .tool-badge {
    font-size: 1.1rem;
  }

  .size-section {
    min-width: 130px;
  }

  .app-footer {
    height: 70px;
    padding: 0 10px;
  }

  .color-btn {
    width: 38px;
    height: 38px;
    min-width: 38px;
  }

  .primary-btn span {
    display: none; /* Icon only on mobile top bar if constrained */
  }

  .primary-btn {
    padding: 8px 12px;
  }
}

@media (max-width: 420px) {
  .app-title {
    font-size: 0.92rem;
  }
  .logo-icon {
    font-size: 1.1rem;
  }
  .primary-btn {
    padding: 6px 10px;
    font-size: 0.8rem;
  }
}