:root {
  --papic-bg: #ffffff;
  --papic-bg-soft: #f8fafb;
  --papic-text: #111216;
  --papic-muted: #555961;
  --papic-border: #e8eaee;
  --papic-cyan: #00827b;
  --papic-cyan-soft: rgba(0, 130, 123, 0.08);
}

body.upscaler-page {
  background-color: var(--papic-bg-soft);
  color: var(--papic-text);
}

.upscaler-main {
  max-width: 920px;
  margin: 0 auto;
  padding: 32px 20px;
}

/* Intro Section */
.upscaler-intro {
  margin-bottom: 32px;
  text-align: left;
}

.upscaler-intro-overline {
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--papic-muted);
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.upscaler-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--papic-cyan);
}

.upscaler-intro-title {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--papic-text);
  margin: 0 0 12px;
  line-height: 1.1;
}

.upscaler-intro-desc {
  font-size: 16px;
  color: var(--papic-muted);
  max-width: 600px;
  line-height: 1.5;
  margin: 0 0 24px;
}

/* Card Container */
.upscaler-card {
  background: var(--papic-bg);
  border: 1px solid var(--papic-border);
  border-radius: 12px;
  box-shadow: 0 12px 32px rgba(17, 18, 22, 0.03);
  overflow: hidden;
  margin-bottom: 32px;
}

/* Upload Area */
.upload-area {
  padding: 48px 24px;
  text-align: center;
  border: 2px dashed var(--papic-border);
  border-radius: 8px;
  margin: 24px;
  background-color: var(--papic-bg-soft);
  cursor: pointer;
  transition: all 0.2s ease;
}

.upload-area:hover, .upload-area.dragover {
  border-color: var(--papic-cyan);
  background-color: var(--papic-cyan-soft);
}

.upload-area.error {
  border-color: #ef4444;
  background-color: rgba(239, 68, 68, 0.05);
}

.upload-icon {
  font-size: 40px;
  color: var(--papic-cyan);
  margin-bottom: 16px;
  background: var(--papic-cyan-soft);
  width: 80px;
  height: 80px;
  line-height: 80px;
  border-radius: 50%;
  display: inline-block;
}

.upload-text {
  font-size: 18px;
  font-weight: 700;
  color: var(--papic-text);
  margin-bottom: 8px;
}

.upload-hint {
  font-size: 14px;
  color: var(--papic-muted);
}

#file-input {
  display: none;
}

/* Preview Section */
.preview-section {
  display: none;
  padding: 24px;
  flex-direction: column;
  gap: 24px;
}

.preview-header {
  display: flex;
  gap: 16px;
  align-items: center;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--papic-border);
}

.preview-thumbnail {
  width: 72px;
  height: 72px;
  border-radius: 8px;
  object-fit: cover;
  border: 1px solid var(--papic-border);
}

.preview-info {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.preview-name {
  font-weight: 700;
  font-size: 16px;
  color: var(--papic-text);
  word-break: break-all;
}

.preview-meta {
  font-size: 14px;
  color: var(--papic-muted);
}

/* Resolution Slider */
.slider-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: var(--papic-bg-soft);
  padding: 20px;
  border-radius: 8px;
  border: 1px solid var(--papic-border);
}

.slider-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.slider-desc {
  font-size: 14px;
  font-weight: 600;
  color: var(--papic-text);
}

.slider-value-badge {
  background: var(--papic-cyan-soft);
  color: var(--papic-cyan);
  padding: 6px 12px;
  border-radius: 20px;
  font-weight: 800;
  font-size: 16px;
}

.slider-input {
  width: 100%;
  accent-color: var(--papic-cyan);
  height: 6px;
  border-radius: 4px;
  outline: none;
  margin: 12px 0;
}

.slider-footer {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--papic-muted);
}

.slider-footer strong {
  color: var(--papic-text);
}

.badge-warning {
  background: rgba(239, 68, 68, 0.1);
  color: #ef4444;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 12px;
  display: inline-block;
  margin-top: 4px;
}

/* Action Area */
.action-area {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.btn {
  padding: 14px 24px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all 0.2s ease;
}

.btn-primary {
  background: var(--papic-cyan);
  color: #ffffff;
}

.btn-primary:hover {
  background: #006B65;
}

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

.btn-secondary {
  background: var(--papic-bg);
  color: var(--papic-text);
  border: 1px solid var(--papic-border);
}

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

.btn-danger {
  background: rgba(239, 68, 68, 0.1);
  color: #ef4444;
}

.btn-danger:hover {
  background: rgba(239, 68, 68, 0.15);
}

/* Processing State */
.processing-state {
  display: none;
  flex-direction: column;
  gap: 20px;
  padding: 48px 24px;
  text-align: center;
  align-items: center;
}

.spinner {
  font-size: 40px;
  color: var(--papic-cyan);
  animation: spin 1s linear infinite;
}

@keyframes spin {
  100% { transform: rotate(360deg); }
}

.progress-container {
  width: 100%;
  max-width: 400px;
  height: 6px;
  background: var(--papic-border);
  border-radius: 4px;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: var(--papic-cyan);
  width: 0%;
  transition: width 0.3s ease;
}

.progress-bar.indeterminate {
  width: 50%;
  animation: indeterminate 1.5s infinite linear;
  transform-origin: 0% 50%;
}

@keyframes indeterminate {
  0% { transform: translateX(-100%); width: 50%; }
  100% { transform: translateX(200%); width: 50%; }
}

.dynamic-text {
  font-size: 16px;
  font-weight: 600;
  color: var(--papic-text);
  min-height: 24px;
}

/* Result Area */
.result-section {
  display: none;
  flex-direction: column;
  padding: 24px;
  gap: 24px;
}

/* Comparison Slider */
.cs-container {
  position: relative;
  overflow: hidden;
  border-radius: 8px;
  cursor: ew-resize;
  width: 100%;
  height: 400px;
  background: var(--papic-bg-soft);
  border: 1px solid var(--papic-border);
  user-select: none;
}
.cs-before, .cs-after {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  pointer-events: none;
}
.cs-after {
  clip-path: inset(0 50% 0 0);
}
.cs-handle {
  position: absolute;
  top: 0; bottom: 0;
  left: 50%;
  width: 2px;
  background: #ffffff;
  cursor: ew-resize;
  transform: translateX(-50%);
  z-index: 10;
  touch-action: none;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}
.cs-handle::before {
  content: '< >';
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: var(--papic-cyan);
  font-weight: bold;
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 32px; height: 32px;
  background: #ffffff;
  border-radius: 50%;
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
  border: 1px solid var(--papic-border);
}

.cs-labels {
  position: absolute;
  top: 16px;
  left: 16px;
  right: 16px;
  display: flex;
  justify-content: space-between;
  pointer-events: none;
  z-index: 5;
}

.cs-label {
  background: rgba(255,255,255,0.9);
  color: var(--papic-text);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
  border: 1px solid var(--papic-border);
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.result-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.result-info {
  text-align: center;
  font-size: 14px;
  color: var(--papic-muted);
}

/* Toast */
.toast-container {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  background: var(--papic-text);
  color: #ffffff;
  padding: 12px 24px;
  border-radius: 8px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.15);
  font-size: 14px;
  font-weight: 500;
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.3s ease;
  border-left: 4px solid var(--papic-cyan);
}

.toast.show {
  opacity: 1;
  transform: translateY(0);
}

.toast.error {
  border-left-color: #ef4444;
}

@media (max-width: 768px) {
  .action-area, .result-actions {
    grid-template-columns: 1fr;
  }
}