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

:root {
  --primary-color: #3b82f6;
  --primary-hover: #2563eb;
  --secondary-color: #6b7280;
  --secondary-hover: #4b5563;
  --success-color: #10b981;
  --error-color: #ef4444;
  --bg-color: #f9fafb;
  --card-bg: #ffffff;
  --text-primary: #111827;
  --text-secondary: #6b7280;
  --border-color: #e5e7eb;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --transition: all 0.3s ease;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

header {
  text-align: center;
  margin-bottom: 3rem;
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
}

.upload-section {
  width: 100%;
  max-width: 600px;
}

.drop-zone {
  background-color: var(--card-bg);
  border: 2px dashed var(--border-color);
  border-radius: 1rem;
  padding: 3rem 2rem;
  text-align: center;
  transition: var(--transition);
  cursor: pointer;
}

.drop-zone:hover,
.drop-zone.drag-over {
  border-color: var(--primary-color);
  background-color: rgba(59, 130, 246, 0.05);
}

.drop-zone-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.upload-icon {
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.drop-zone-text {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
}

.drop-zone-or {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.file-input {
  display: none;
}

.file-input-label {
  display: inline-block;
  padding: 0.75rem 2rem;
  background-color: var(--primary-color);
  color: white;
  font-weight: 500;
  border-radius: 0.5rem;
  cursor: pointer;
  transition: var(--transition);
}

.file-input-label:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.file-input-label:active {
  transform: translateY(0);
}

.file-info {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: 0.5rem;
}

.preview-section {
  width: 100%;
  max-width: 900px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
}

.canvas-container {
  width: 100%;
  background-color: var(--card-bg);
  border-radius: 1rem;
  padding: 1.5rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  justify-content: center;
  align-items: center;
}

#preview-canvas {
  max-width: 100%;
  max-height: 70vh;
  display: block;
  border-radius: 0.5rem;
}

.action-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 500;
  border: none;
  border-radius: 0.5rem;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

.btn:focus {
  outline: 2px solid transparent;
  outline-offset: 2px;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.3);
}

.btn svg {
  flex-shrink: 0;
}

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

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background-color: var(--secondary-color);
  color: white;
}

.btn-secondary:hover {
  background-color: var(--secondary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary:active {
  transform: translateY(0);
}

.error-message {
  max-width: 600px;
  width: 100%;
  padding: 1rem 1.5rem;
  background-color: #fee2e2;
  border: 1px solid var(--error-color);
  border-radius: 0.5rem;
  color: #991b1b;
  margin-top: 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.error-message::before {
  content: "⚠";
  font-size: 1.5rem;
  flex-shrink: 0;
}

.loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 2rem;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border-color);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

.loading p {
  color: var(--text-secondary);
  font-size: 1rem;
}

.hidden {
  display: none !important;
}

footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-top: auto;
}

@media (max-width: 768px) {
  header h1 {
    font-size: 2rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .drop-zone {
    padding: 2rem 1rem;
  }

  .drop-zone-text {
    font-size: 1rem;
  }

  .canvas-container {
    padding: 1rem;
  }

  #preview-canvas {
    max-height: 60vh;
  }

  .action-buttons {
    flex-direction: column;
    width: 100%;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 1rem 0.5rem;
  }

  header h1 {
    font-size: 1.75rem;
  }

  .drop-zone {
    padding: 1.5rem 1rem;
  }

  .upload-icon {
    width: 48px;
    height: 48px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

.file-input-label:focus-visible,
.btn:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}