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

:root {
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --success: #10b981;
  --success-hover: #059669;
  --secondary: #64748b;
  --secondary-hover: #475569;
  --background: #0f172a;
  --surface: #1e293b;
  --surface-light: #334155;
  --text: #f8fafc;
  --text-muted: #94a3b8;
  --border: #475569;
  --accent: #22d3ee;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: var(--background);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.6;
}

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

/* Header */
header {
  text-align: center;
  margin-bottom: 2rem;
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-top: 0.5rem;
}

/* Upload Section */
.upload-section {
  margin-bottom: 2rem;
}

.drop-zone {
  border: 2px dashed var(--border);
  border-radius: 16px;
  padding: 3rem 2rem;
  text-align: center;
  background: var(--surface);
  transition: all 0.3s ease;
  cursor: pointer;
}

.drop-zone:hover,
.drop-zone.dragover {
  border-color: var(--primary);
  background: rgba(99, 102, 241, 0.1);
}

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

.upload-icon {
  width: 64px;
  height: 64px;
  color: var(--primary);
}

.drop-zone p {
  font-size: 1.2rem;
  color: var(--text);
}

.drop-zone span {
  color: var(--text-muted);
}

.browse-btn {
  display: inline-block;
  padding: 0.75rem 2rem;
  background: var(--primary);
  color: white;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease;
}

.browse-btn:hover {
  background: var(--primary-hover);
}

.file-info {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-top: 1rem;
}

/* Preview Section */
.preview-section {
  margin-bottom: 2rem;
}

.preview-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

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

.preview-box {
  background: var(--surface);
  border-radius: 12px;
  padding: 1rem;
}

.preview-box h3 {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.image-wrapper {
  background: var(--surface-light);
  border-radius: 8px;
  min-height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.image-wrapper img {
  max-width: 100%;
  max-height: 300px;
  object-fit: contain;
}

.placeholder {
  color: var(--text-muted);
  text-align: center;
  padding: 2rem;
}

.image-stats {
  margin-top: 0.75rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Controls Section */
.controls-section {
  background: var(--surface);
  border-radius: 16px;
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.controls-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.control-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
}

.control-group select,
.control-group input[type="number"] {
  padding: 0.75rem 1rem;
  background: var(--surface-light);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 1rem;
  transition: border-color 0.3s ease;
}

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

.control-group input[type="range"] {
  width: 100%;
  height: 8px;
  background: var(--surface-light);
  border-radius: 4px;
  -webkit-appearance: none;
  appearance: none;
}

.control-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  background: var(--primary);
  border-radius: 50%;
  cursor: pointer;
}

.toggle-label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  cursor: pointer;
}

.toggle-label input[type="checkbox"] {
  width: 20px;
  height: 20px;
  accent-color: var(--primary);
}

.toggle-text {
  color: var(--text);
}

/* Presets */
.presets {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.presets span {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.preset-btn {
  padding: 0.5rem 1rem;
  background: var(--surface-light);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  font-size: 0.875rem;
  cursor: pointer;
  transition: all 0.3s ease;
}

.preset-btn:hover {
  border-color: var(--primary);
  background: rgba(99, 102, 241, 0.2);
}

/* Actions */
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

.btn {
  padding: 0.875rem 2rem;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

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

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

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

.btn-success:hover:not(:disabled) {
  background: var(--success-hover);
}

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

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

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Results Section */
.results-section {
  margin-bottom: 2rem;
}

.results-card {
  background: var(--surface);
  border-radius: 12px;
  padding: 1.5rem;
}

.results-card h3 {
  color: var(--accent);
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
}

.result-item {
  text-align: center;
  padding: 1rem;
  background: var(--surface-light);
  border-radius: 8px;
}

.result-label {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.result-value {
  display: block;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text);
}

/* Footer */
footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* Loading state */
.loading {
  pointer-events: none;
  opacity: 0.7;
}

/* Animations */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.btn-loading {
  animation: pulse 1.5s infinite;
}

/* Mobile optimizations */
@media (max-width: 480px) {
  .container {
    padding: 1rem;
  }

  header h1 {
    font-size: 1.75rem;
  }

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

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

  .controls-grid {
    grid-template-columns: 1fr;
  }

  .presets {
    justify-content: center;
  }

  .actions {
    flex-direction: column;
  }

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