:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: #1e293b;
  --bg-hover: #334155;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --success: #22c55e;
  --warning: #f59e0b;
  --error: #ef4444;
  --border: #334155;
  --radius: 12px;
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.3);
}

[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #f1f5f9;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.1);
}

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
header {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: bold;
  color: white;
}

.logo h1 {
  font-size: 20px;
  font-weight: 700;
}

.logo span {
  font-size: 12px;
  color: var(--text-muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.token-badge {
  background: var(--bg-hover);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 13px;
  color: var(--text-secondary);
}

.token-count {
  color: var(--accent);
  font-weight: 700;
}

.theme-toggle {
  background: var(--bg-hover);
  border: none;
  padding: 8px;
  border-radius: 8px;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 18px;
}

/* Main Layout */
main {
  padding: 32px 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

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

/* Upload Zone */
.upload-section {
  grid-column: 1 / -1;
}

.upload-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 48px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  background: var(--bg-card);
}

.upload-zone:hover,
.upload-zone.dragover {
  border-color: var(--accent);
  background: rgba(59, 130, 246, 0.05);
}

.upload-icon {
  font-size: 48px;
  margin-bottom: 16px;
}

.upload-zone h2 {
  font-size: 18px;
  margin-bottom: 8px;
}

.upload-zone p {
  color: var(--text-muted);
  font-size: 14px;
}

.privacy-notice {
  font-size: 12px;
  color: var(--success);
  margin-top: 8px;
  opacity: 0.9;
}

.upload-options {
  margin-top: 20px;
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.option-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.option-group label {
  font-size: 12px;
  color: var(--text-muted);
}

.option-group select {
  background: var(--bg-hover);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 10px;
  font-size: 13px;
}

/* Task List */
.task-list {
  background: var(--bg-card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
}

.task-list-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.task-list-header h3 {
  font-size: 16px;
}

.task-item {
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background 0.2s;
}

.task-item:hover {
  background: var(--bg-hover);
}

.task-item:last-child {
  border-bottom: none;
}

.task-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.task-name {
  font-size: 14px;
  font-weight: 500;
}

.task-badge {
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.badge-uploaded { background: rgba(59,130,246,0.15); color: var(--accent); }
.badge-queued { background: rgba(245,158,11,0.15); color: var(--warning); }
.badge-processing { background: rgba(245,158,11,0.15); color: var(--warning); }
.badge-completed { background: rgba(34,197,94,0.15); color: var(--success); }
.badge-failed { background: rgba(239,68,68,0.15); color: var(--error); }

.task-progress {
  height: 4px;
  background: var(--bg-hover);
  border-radius: 2px;
  overflow: hidden;
}

.task-progress-bar {
  height: 100%;
  background: var(--accent);
  border-radius: 2px;
  transition: width 0.5s ease;
}

.task-meta {
  display: flex;
  gap: 12px;
  margin-top: 6px;
  font-size: 12px;
  color: var(--text-muted);
}

.empty-state {
  padding: 48px 20px;
  text-align: center;
  color: var(--text-muted);
}

/* Preview Panel */
.preview-section {
  background: var(--bg-card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  max-height: 600px;
}

.preview-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.preview-header h3 {
  font-size: 16px;
}

.preview-actions {
  display: flex;
  gap: 8px;
}

.btn {
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 500;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

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

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

.btn-secondary {
  background: var(--bg-hover);
  color: var(--text-primary);
}

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

.preview-content {
  padding: 20px;
  overflow-y: auto;
  flex: 1;
  font-size: 14px;
  line-height: 1.7;
}

.preview-content pre {
  background: var(--bg-primary);
  padding: 12px;
  border-radius: 6px;
  overflow-x: auto;
}

.preview-content code {
  font-family: 'Fira Code', monospace;
  font-size: 13px;
}

.preview-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0;
}

.preview-content th,
.preview-content td {
  border: 1px solid var(--border);
  padding: 8px 12px;
  text-align: left;
  font-size: 13px;
}

.preview-content th {
  background: var(--bg-hover);
  font-weight: 600;
}

.preview-content img {
  max-width: 100%;
  border-radius: 6px;
  margin: 8px 0;
}

.preview-placeholder {
  padding: 48px 20px;
  text-align: center;
  color: var(--text-muted);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 14px;
  color: white;
  animation: slideIn 0.3s ease;
  box-shadow: var(--shadow);
}

.toast-success { background: var(--success); }
.toast-error { background: var(--error); }
.toast-info { background: var(--accent); }

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* Spinner */
.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid var(--border);
  border-top: 2px solid var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* Skip Link (Accessibility) */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--accent);
  color: white;
  padding: 8px 16px;
  z-index: 1000;
  font-size: 14px;
  border-radius: 0 0 4px 0;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 0;
}

/* Screen Reader Only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Features Section */
.features-section {
  grid-column: 1 / -1;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.feature-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--accent);
}

.feature-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  margin-top: 32px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--text-muted);
}

.footer-content nav {
  display: flex;
  gap: 8px;
  align-items: center;
}

.footer-content a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s;
}

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

/* Ad Banner */
.ad-banner {
  grid-column: 1 / -1;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
  color: var(--text-muted);
  font-size: 12px;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
}