/* 
 * Pixel Art Transformer - Main Stylesheet
 * Modern UI with responsive design for desktop and tablet devices
 */

/* ===== Base Styles ===== */
:root {
  /* Color Variables */
  --primary-color: #6366f1;
  --primary-hover: #4f46e5;
  --secondary-color: #f59e0b;
  --text-color: #1f2937;
  --text-light: #6b7280;
  --bg-color: #ffffff;
  --bg-secondary: #f9fafb;
  --border-color: #e5e7eb;
  --success-color: #10b981;
  --error-color: #ef4444;
  --info-color: #3b82f6;
  --warning-color: #f59e0b;
  
  /* Spacing Variables */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-xxl: 3rem;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
  --transition-slow: 500ms ease;
}

/* Dark Mode Variables */
@media (prefers-color-scheme: dark) {
  :root {
    --text-color: #f9fafb;
    --text-light: #d1d5db;
    --bg-color: #111827;
    --bg-secondary: #1f2937;
    --border-color: #374151;
  }
}

/* Reset and Base Styles */
*, *::before, *::after {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: var(--text-color);
  background-color: var(--bg-color);
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4, h5, h6 {
  margin-top: 0;
  margin-bottom: var(--spacing-md);
  font-weight: 600;
  line-height: 1.2;
}

p {
  margin-top: 0;
  margin-bottom: var(--spacing-md);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-hover);
}

img {
  max-width: 100%;
  height: auto;
}

button, .button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
  font-size: inherit;
  padding: 0;
  margin: 0;
}

.hidden {
  display: none !important;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ===== Layout ===== */
.app-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md);
  width: 100%;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.app-header {
  text-align: center;
  padding: var(--spacing-lg) 0;
  margin-bottom: var(--spacing-lg);
}

.app-header h1 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
  color: var(--primary-color);
}

.app-header p {
  font-size: 1.2rem;
  color: var(--text-light);
  margin-bottom: 0;
}

.app-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
}

.app-footer {
  margin-top: var(--spacing-xl);
  padding: var(--spacing-lg) 0;
  text-align: center;
  color: var(--text-light);
  font-size: 0.9rem;
}

/* ===== Section Styles ===== */
section {
  background-color: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
}

section h2 {
  margin-top: 0;
  margin-bottom: var(--spacing-lg);
  font-size: 1.5rem;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

/* ===== Upload Section ===== */
.upload-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
}

@media (max-width: 768px) {
  .upload-container {
    grid-template-columns: 1fr;
  }
}

.upload-area {
  border: 2px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--spacing-xl);
  text-align: center;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 250px;
  position: relative;
}

.upload-area.drag-over {
  border-color: var(--primary-color);
  background-color: rgba(99, 102, 241, 0.05);
}

.upload-icon {
  width: 64px;
  height: 64px;
  margin-bottom: var(--spacing-md);
}

.upload-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.upload-button {
  display: inline-block;
  background-color: var(--primary-color);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-full);
  font-weight: 500;
  margin-top: var(--spacing-md);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.upload-button:hover {
  background-color: var(--primary-hover);
}

.upload-preview {
  overflow: hidden;
}

.upload-preview h3 {
  margin-top: 0;
  margin-bottom: var(--spacing-md);
  font-size: 1.2rem;
}

.preview-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: var(--spacing-md);
  max-height: 300px;
  overflow-y: auto;
  padding-right: var(--spacing-sm);
}

.preview-item {
  position: relative;
  border-radius: var(--radius-sm);
  overflow: hidden;
  aspect-ratio: 1;
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.preview-item:hover {
  transform: scale(1.05);
}

.preview-item.selected {
  outline: 3px solid var(--primary-color);
}

.preview-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.remove-btn {
  position: absolute;
  top: 5px;
  right: 5px;
  width: 20px;
  height: 20px;
  background-color: rgba(0, 0, 0, 0.5);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.preview-item:hover .remove-btn {
  opacity: 1;
}

.file-name {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: rgba(0, 0, 0, 0.7);
  color: white;
  font-size: 0.8rem;
  padding: var(--spacing-xs);
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ===== Configuration Section ===== */
.config-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

.config-group {
  margin-bottom: var(--spacing-md);
}

.config-group label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
}

.slider-container {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: var(--border-color);
  border-radius: var(--radius-full);
  outline: none;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.slider::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--primary-color);
  cursor: pointer;
  transition: background-color var(--transition-fast);
  border: none;
}

.slider::-webkit-slider-thumb:hover {
  background: var(--primary-hover);
}

.slider::-moz-range-thumb:hover {
  background: var(--primary-hover);
}

.slider-value {
  min-width: 60px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.select-input {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-color);
  color: var(--text-color);
  font-size: 1rem;
  transition: border-color var(--transition-fast);
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--spacing-md) center;
  padding-right: var(--spacing-xl);
}

.select-input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.number-input {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-color);
  color: var(--text-color);
  font-size: 1rem;
  transition: border-color var(--transition-fast);
}

.number-input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.color-palette {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.color-container {
  position: relative;
}

.color-swatch {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.color-swatch:hover {
  transform: scale(1.1);
}

.remove-color-btn {
  position: absolute;
  top: -8px;
  right: -8px;
  width: 20px;
  height: 20px;
  background-color: var(--error-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.color-container:hover .remove-color-btn {
  opacity: 1;
}

/* ===== Preview Section ===== */
.preview-controls {
  display: flex;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
  flex-wrap: wrap;
}

.preview-display {
  position: relative;
  background-color: #000;
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 300px;
}

.preview-image-container {
  position: relative;
  max-width: 100%;
  max-height: 500px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.preview-image-container img,
.preview-image-container canvas {
  max-width: 100%;
  max-height: 500px;
  object-fit: contain;
}

/* ===== Batch Processing Section ===== */
.batch-controls {
  margin-bottom: var(--spacing-lg);
}

.batch-progress {
  margin-top: var(--spacing-md);
}

.progress-bar {
  height: 10px;
  background-color: var(--border-color);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--spacing-sm);
}

.progress-fill {
  height: 100%;
  background-color: var(--primary-color);
  border-radius: var(--radius-full);
  transition: width var(--transition-normal);
}

.progress-text {
  font-size: 0.9rem;
  color: var(--text-light);
  text-align: center;
}

.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: var(--spacing-md);
}

.result-item {
  position: relative;
  border-radius: var(--radius-sm);
  overflow: hidden;
  aspect-ratio: 1;
  background-color: #000;
}

.result-image {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.result-info {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: rgba(0, 0, 0, 0.7);
  color: white;
  font-size: 0.8rem;
  padding: var(--spacing-xs);
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.download-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 32px;
  height: 32px;
  background-color: rgba(0, 0, 0, 0.5);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.result-item:hover .download-btn {
  opacity: 1;
}

.download-icon {
  display: inline-block;
  transform: translateY(-2px);
}

/* ===== Download Section ===== */
.download-options {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

.option-group {
  margin-bottom: var(--spacing-md);
}

.download-buttons {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

/* ===== Buttons ===== */
.primary-button {
  background-color: var(--primary-color);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 500;
  cursor: pointer;
  transition: background-color var(--transition-fast);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
}

.primary-button:hover {
  background-color: var(--primary-hover);
}

.primary-button:disabled {
  background-color: var(--border-color);
  cursor: not-allowed;
}

.secondary-button {
  background-color: transparent;
  color: var(--text-color);
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid var(--border-color);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
}

.secondary-button:hover {
  background-color: var(--bg-secondary);
  border-color: var(--text-light);
}

.secondary-button.active {
  background-color: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
}

.secondary-button:disabled {
  color: var(--text-light);
  cursor: not-allowed;
}

/* ===== Toast Notifications ===== */
.toast-container {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 9999;
  pointer-events: none;
}

.toast {
  background-color: var(--bg-color);
  color: var(--text-color);
  padding: 12px 16px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-width: 300px;
  max-width: 450px;
  animation: toast-in 0.3s ease forwards;
  pointer-events: auto;
  position: relative;
  overflow: hidden;
}

.toast-message {
  flex: 1;
  padding-right: 10px;
}

.toast-close {
  background: none;
  border: none;
  color: var(--text-light);
  font-size: 1.2rem;
  cursor: pointer;
  padding: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color var(--transition-fast);
}

.toast-close:hover {
  color: var(--text-color);
}

.toast::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
}

.toast-success {
  border-left: 4px solid var(--success-color);
}

.toast-error {
  border-left: 4px solid var(--error-color);
}

.toast-info {
  border-left: 4px solid var(--info-color);
}

.toast-warning {
  border-left: 4px solid var(--warning-color);
}

.toast-hide {
  animation: toast-out 0.3s ease forwards;
}

@keyframes toast-in {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes toast-out {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(100%);
    opacity: 0;
  }
}

/* ===== Loading Indicators ===== */
.loading-indicator {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.7);
  color: white;
  z-index: 10;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s linear infinite;
  margin-bottom: var(--spacing-sm);
}

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

/* Global Loading Overlay */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  opacity: 1;
  transition: opacity var(--transition-normal);
}

.loading-overlay.hidden {
  display: none;
}

.loading-overlay.fade-out {
  opacity: 0;
}

.loading-spinner {
  width: 60px;
  height: 60px;
  border: 5px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s linear infinite;
  margin-bottom: var(--spacing-md);
}

.loading-message {
  color: white;
  font-size: 1.2rem;
  margin-bottom: var(--spacing-lg);
  text-align: center;
}

.loading-progress-container {
  width: 300px;
  max-width: 80vw;
}

.loading-progress-container.hidden {
  display: none;
}

.loading-progress-bar {
  height: 8px;
  background-color: rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--spacing-sm);
}

.loading-progress-fill {
  height: 100%;
  background-color: white;
  border-radius: var(--radius-full);
  transition: width var(--transition-normal);
}

.loading-progress-text {
  color: white;
  font-size: 0.9rem;
  text-align: center;
}

/* Element Loading Indicators */
.element-loading-indicator {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 5;
  opacity: 1;
  transition: opacity var(--transition-normal);
}

.element-loading-indicator.fade-out {
  opacity: 0;
}

.element-spinner {
  width: 24px;
  height: 24px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s linear infinite;
}

.element-progress-bar {
  width: 80%;
  height: 4px;
  background-color: rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-top: var(--spacing-sm);
}

.element-progress-fill {
  height: 100%;
  background-color: white;
  border-radius: var(--radius-full);
  transition: width var(--transition-normal);
}

/* Button Loading State */
button.loading {
  position: relative;
  color: transparent !important;
}

button.loading::after {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  top: calc(50% - 8px);
  left: calc(50% - 8px);
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 1s linear infinite;
}

/* Accessibility Focus Styles */
:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Keyboard Navigation Indicator */
body:not(.using-mouse) :focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Error Styles */
.error-message {
  color: var(--error-color);
  font-size: 0.9rem;
  margin-top: var(--spacing-xs);
}

.input-error {
  border-color: var(--error-color) !important;
}

/* Compatibility Warning Banner */
.compatibility-warning {
  background-color: var(--warning-color);
  color: white;
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
  border-radius: var(--radius-md);
  text-align: center;
}

/* Responsive Adjustments */
@media (max-width: 768px) {
  .app-header h1 {
    font-size: 2rem;
  }
  
  .app-header p {
    font-size: 1rem;
  }
  
  section {
    padding: var(--spacing-md);
  }
  
  .preview-display {
    min-height: 200px;
  }
  
  .preview-image-container img,
  .preview-image-container canvas {
    max-height: 300px;
  }
  
  .download-buttons {
    flex-direction: column;
  }
  
  .primary-button, .secondary-button {
    width: 100%;
  }
}

/* Print Styles */
@media print {
  .app-container {
    padding: 0;
  }
  
  section {
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #ddd;
  }
  
  .upload-section, .config-section, .batch-section, .download-section {
    display: none;
  }
  
  .preview-section {
    page-break-inside: avoid;
  }
}

/* Animation for UI Elements */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.fade-in {
  animation: fadeIn var(--transition-normal) forwards;
}

/* Transitions for UI Elements */
.section-transition {
  transition: transform var(--transition-normal), opacity var(--transition-normal);
}

.section-transition.hidden {
  transform: translateY(20px);
  opacity: 0;
}