:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-tertiary: #1a1a24;
  --text-primary: #f0f0f5;
  --text-secondary: #a0a0b0;
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --success: #22c55e;
  --error: #ef4444;
  --border: #2a2a3a;
  --radius: 12px;
  --transition: 0.2s ease;
}

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

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

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

header {
  text-align: center;
  margin-bottom: 2.5rem;
}

@media (min-width: 641px) {
  header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    text-align: left;
  }

  header .header-text {
    display: flex;
    flex-direction: column;
  }
}

.logo {
  width: 80px;
  height: 80px;
  border-radius: 16px;
  margin-bottom: 1rem;
}

@media (min-width: 641px) {
  .logo {
    width: 56px;
    height: 56px;
    border-radius: 12px;
    margin-bottom: 0;
  }
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent) 0%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

@media (min-width: 641px) {
  h1 {
    font-size: 2rem;
    margin-bottom: 0.25rem;
  }
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

@media (min-width: 641px) {
  .subtitle {
    font-size: 1rem;
  }
}

h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.how-it-works {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.how-it-works p {
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.how-it-works p:last-child {
  margin-bottom: 0;
}

.how-it-works strong {
  color: var(--text-primary);
}

.supported-generators {
  font-size: 0.9rem;
  color: var(--text-secondary);
  opacity: 0.8;
  margin-top: 0.5rem;
}

.example-section {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.example-description {
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
}

.example-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 640px) {
  .example-grid {
    grid-template-columns: 1fr;
  }
}

.example-item {
  position: relative;
  border-radius: 8px;
  overflow: hidden;
  background: var(--bg-tertiary);
}

.example-item img {
  width: 100%;
  height: auto;
  display: block;
}

.example-item.example-result {
  background:
    linear-gradient(45deg, #333 25%, transparent 25%),
    linear-gradient(-45deg, #333 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #333 75%),
    linear-gradient(-45deg, transparent 75%, #333 75%);
  background-size: 16px 16px;
  background-position: 0 0, 0 8px, 8px -8px, -8px 0px;
  background-color: #222;
}

.example-label {
  position: absolute;
  bottom: 0.5rem;
  left: 0.5rem;
  background: rgba(0, 0, 0, 0.7);
  color: #fff;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
}

.upload-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

@media (max-width: 640px) {
  .upload-section {
    grid-template-columns: 1fr;
  }
}

.drop-zone {
  position: relative;
  background: var(--bg-secondary);
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
  cursor: pointer;
  transition: all var(--transition);
  min-height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.drop-zone:hover {
  border-color: var(--accent);
  background: var(--bg-tertiary);
}

.drop-zone.drag-over {
  border-color: var(--accent);
  background: rgba(99, 102, 241, 0.1);
  transform: scale(1.02);
}

.drop-zone.has-image {
  padding: 0.5rem;
  border-style: solid;
  border-color: var(--border);
}

.drop-zone.has-image .drop-zone-content {
  display: none;
}

.drop-zone-content {
  pointer-events: none;
}

.drop-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 1rem;
  color: var(--text-secondary);
}

.drop-icon svg {
  width: 100%;
  height: 100%;
}

.drop-label {
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.white-bg {
  background: #fff;
  color: #000;
  padding: 0.1em 0.4em;
  border-radius: 4px;
}

.black-bg {
  background: #000;
  color: #fff;
  padding: 0.1em 0.4em;
  border-radius: 4px;
  border: 1px solid var(--border);
}

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

.preview-image {
  display: none;
  max-width: 100%;
  max-height: 300px;
  border-radius: calc(var(--radius) - 4px);
  object-fit: contain;
}

.drop-zone.has-image .preview-image {
  display: block;
}

.clear-btn {
  display: none;
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  width: 28px;
  height: 28px;
  border: none;
  background: rgba(0, 0, 0, 0.7);
  color: #fff;
  border-radius: 50%;
  font-size: 1.25rem;
  cursor: pointer;
  transition: all var(--transition);
  line-height: 1;
}

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

.drop-zone.has-image .clear-btn {
  display: block;
}

.action-section {
  text-align: center;
  margin-bottom: 2rem;
}

.process-btn {
  background: linear-gradient(135deg, var(--accent) 0%, #a855f7 100%);
  color: #fff;
  border: none;
  padding: 1rem 2.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.process-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px rgba(99, 102, 241, 0.3);
}

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

.process-btn.loading .btn-text {
  visibility: hidden;
}

.process-btn .btn-loading {
  display: none;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  align-items: center;
  gap: 0.5rem;
}

.process-btn.loading .btn-loading {
  display: flex;
}

.spinner {
  width: 20px;
  height: 20px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.error-message {
  color: var(--error);
  margin-top: 1rem;
  font-size: 0.9rem;
  min-height: 1.5em;
}

.result-section {
  display: none;
  text-align: center;
}

.result-section.visible {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}


#resultCanvas, #beforeCanvas {
  max-width: 100%;
  height: auto;
  display: block;
}

.compare-container {
  position: relative;
  display: inline-block;
  background:
    linear-gradient(45deg, #333 25%, transparent 25%),
    linear-gradient(-45deg, #333 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #333 75%),
    linear-gradient(-45deg, transparent 75%, #333 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
  background-color: #222;
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 0.75rem;
  cursor: ew-resize;
  user-select: none;
}

.compare-after {
  position: relative;
  display: block;
}

.compare-after canvas {
  display: block;
  max-width: 100%;
  height: auto;
}

.compare-before {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  overflow: hidden;
  z-index: 2;
  clip-path: inset(0 100% 0 0);
}

.compare-before canvas {
  display: block;
  max-width: 100%;
  height: auto;
}

.compare-hint {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-bottom: 1.5rem;
}

.compare-label {
  position: absolute;
  bottom: 0.75rem;
  background: rgba(0, 0, 0, 0.7);
  color: #fff;
  padding: 0.25rem 0.75rem;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  z-index: 5;
}

.compare-before .compare-label {
  left: 0.75rem;
}

.compare-after .compare-label {
  right: 0.75rem;
}

.compare-slider {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0%;
  width: 4px;
  background: #fff;
  z-index: 10;
  transform: translateX(-50%);
}

.compare-handle {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 40px;
  height: 40px;
  background: #fff;
  border-radius: 50%;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
}

.compare-handle::before,
.compare-handle::after {
  content: '';
  position: absolute;
  width: 0;
  height: 0;
  border-style: solid;
}

.compare-handle::before {
  left: 8px;
  border-width: 6px 8px 6px 0;
  border-color: transparent #333 transparent transparent;
}

.compare-handle::after {
  right: 8px;
  border-width: 6px 0 6px 8px;
  border-color: transparent transparent transparent #333;
}

.download-options {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.format-toggle {
  display: flex;
  background: var(--bg-tertiary);
  border-radius: 8px;
  padding: 4px;
  gap: 4px;
}

.format-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.5rem 1.25rem;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 6px;
  cursor: pointer;
  transition: all var(--transition);
}

.format-btn:hover {
  color: var(--text-primary);
}

.format-btn.active {
  background: var(--accent);
  color: #fff;
}

.download-btn {
  background: var(--success);
  color: #fff;
  border: none;
  padding: 0.875rem 2rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.download-btn:hover {
  background: #16a34a;
  transform: translateY(-2px);
}

.download-btn svg {
  width: 20px;
  height: 20px;
}

footer {
  text-align: center;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

footer .credit {
  margin-top: 0.5rem;
}

footer a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}

footer a:hover {
  color: var(--accent-hover);
}