:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-success: #16a34a;
  --color-success-dark: #15803d;
  --color-danger: #dc2626;
  --color-danger-dark: #b91c1c;
  --color-purple: #9333ea;
  --color-purple-dark: #7e22ce;

  --color-gray-50: #f9fafb;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-600: #4b5563;
  --color-gray-800: #1f2937;

  --color-bg-gradient-from: #e0f2fe;
  --color-bg-gradient-to: #ede9fe;

  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 0.75rem;
  --spacing-lg: 1rem;
  --spacing-xl: 1.5rem;

  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.625rem;
  --radius-full: 9999px;

  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    sans-serif;
  background: linear-gradient(135deg, var(--color-bg-gradient-from) 0%, var(--color-bg-gradient-to) 100%);
  min-height: 100vh;
  padding: var(--spacing-lg);
}

.container {
  max-width: 100%;
  margin: 0 auto;
}

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

@media (min-width: 1024px) {
  .layout {
    flex-direction: row;
    align-items: flex-start;
  }

  .card.controls {
    flex: 0 0 400px;
    position: sticky;
    top: var(--spacing-lg);
  }

  .card.preview {
    flex: 1;
    min-width: 0;
  }
}

h1 {
  font-size: 1.875rem;
  font-weight: bold;
  color: var(--color-gray-800);
  margin-bottom: var(--spacing-sm);
  text-align: center;
}

.subtitle {
  font-size: 0.875rem;
  color: var(--color-gray-600);
  margin-bottom: var(--spacing-xl);
  text-align: center;
}

.card {
  background: white;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

button {
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-lg) var(--spacing-xl);
}

button:disabled {
  background: var(--color-gray-300) !important;
  cursor: not-allowed;
}

button:active:not(:disabled) {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--color-primary);
  color: white;
  width: 100%;
}

.btn-primary:active:not(:disabled) {
  background: var(--color-primary-dark);
}

.btn-success {
  background: var(--color-success);
  color: white;
  flex: 1;
}

.btn-success:active:not(:disabled) {
  background: var(--color-success-dark);
}

.btn-danger {
  background: var(--color-danger);
  color: white;
  flex: 1;
}

.btn-danger:active:not(:disabled) {
  background: var(--color-danger-dark);
}

.btn-purple {
  background: var(--color-purple);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
}

.btn-purple:active:not(:disabled) {
  background: var(--color-purple-dark);
}

.button-row {
  display: flex;
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.progress-container {
  margin-top: var(--spacing-lg);
}

.progress-info {
  display: flex;
  justify-content: space-between;
  font-size: 0.875rem;
  color: var(--color-gray-600);
  margin-bottom: var(--spacing-sm);
}

.progress-bar {
  width: 100%;
  height: var(--radius-lg);
  background: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--color-primary);
  transition: width 0.3s;
}

.stats {
  text-align: center;
  margin-top: var(--spacing-lg);
}

.stats-main {
  color: var(--color-gray-800);
  font-weight: 500;
}

.stats-detail {
  font-size: 0.875rem;
  color: var(--color-gray-600);
  margin-top: var(--spacing-xs);
}

.preview-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-lg);
}

.preview-header h2 {
  font-size: 1.25rem;
  font-weight: bold;
  color: var(--color-gray-800);
}

.canvas-container {
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-sm);
  background: var(--color-gray-50);
  overflow: visible;
}

.empty-state {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 16rem;
  color: var(--color-gray-400);
}

canvas {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
}

.hidden {
  display: none;
}

.spinner {
  display: inline-block;
  width: 1.5rem;
  height: 1.5rem;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

.thumbnail-container {
  margin-top: var(--spacing-lg);
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  background: var(--color-gray-50);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
}

.thumbnail {
  position: relative;
  aspect-ratio: 1;
  cursor: pointer;
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 2px solid transparent;
  transition: all 0.2s;
}

.thumbnail:hover {
  border-color: var(--color-primary);
  transform: scale(1.05);
}

.thumbnail.selected {
  border-color: var(--color-purple);
  box-shadow: 0 0 0 2px var(--color-purple);
}

.thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}