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

:root {
  --primary: #0d9488;
  --primary-light: #5eead4;
  --primary-dark: #0f766e;
  --bg: #f8fafc;
  --surface: #ffffff;
  --text: #1e293b;
  --text-secondary: #64748b;
  --border: #e2e8f0;
  --success: #10b981;
  --danger: #ef4444;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
}

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

.app {
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 20px;
}

.header {
  text-align: center;
  margin-bottom: 40px;
}

.header h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Dropzone */
.dropzone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 60px 40px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s ease;
  background: var(--surface);
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--primary);
  background: #f0fdfa;
}

.upload-icon {
  width: 48px;
  height: 48px;
  color: var(--primary);
  margin-bottom: 16px;
}

.drop-text {
  font-size: 1.1rem;
  font-weight: 500;
  margin-bottom: 8px;
}

.drop-hint {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* Settings Panel */
.settings-panel {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 24px;
  margin-top: 24px;
  box-shadow: var(--shadow);
}

.settings-panel h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text);
}

.settings-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 24px;
}

@media (max-width: 600px) {
  .settings-grid {
    grid-template-columns: 1fr;
  }
}

.setting-item label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.setting-item label span {
  color: var(--primary-dark);
  font-weight: 600;
}

.setting-item input[type="range"] {
  width: 100%;
  height: 6px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--border);
  border-radius: 3px;
  outline: none;
}

.setting-item input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--primary);
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.setting-item select {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.9rem;
  background: var(--surface);
  cursor: pointer;
  outline: none;
}

.setting-item select:focus {
  border-color: var(--primary);
}

.range-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

.btn-compress {
  width: 100%;
  padding: 14px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

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

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

/* Results */
.results-section {
  margin-top: 24px;
}

.results-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.results-header h3 {
  font-size: 1rem;
  font-weight: 600;
}

.btn-download-all {
  padding: 8px 16px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s;
}

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

.results-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.result-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  display: grid;
  grid-template-columns: 60px 1fr auto;
  align-items: center;
  gap: 16px;
}

.result-thumb {
  width: 60px;
  height: 60px;
  border-radius: 8px;
  object-fit: cover;
  background: var(--bg);
}

.result-info {
  min-width: 0;
}

.result-name {
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.result-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 4px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.result-savings {
  color: var(--success);
  font-weight: 600;
}

.result-savings.negative {
  color: var(--danger);
}

.size-badge {
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
}

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

.btn-download {
  padding: 8px 14px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: background 0.2s;
  white-space: nowrap;
}

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

.btn-preview {
  padding: 8px 14px;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.btn-preview:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* Loading Overlay */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(255,255,255,0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  backdrop-filter: blur(4px);
}

.loading-content {
  text-align: center;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto 16px;
}

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

.loading-content p {
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.progress-bar {
  width: 200px;
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  overflow: hidden;
  margin: 0 auto;
}

.progress-fill {
  height: 100%;
  background: var(--primary);
  border-radius: 2px;
  transition: width 0.3s ease;
  width: 0%;
}

/* Preview Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  padding: 20px;
}

.modal-content {
  background: var(--surface);
  border-radius: var(--radius);
  max-width: 90vw;
  max-height: 90vh;
  overflow: auto;
  padding: 24px;
  position: relative;
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 32px;
  height: 32px;
  border: none;
  background: var(--bg);
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.preview-compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 16px;
}

.preview-compare img {
  max-width: 100%;
  border-radius: 8px;
  background: repeating-conic-gradient(#f0f0f0 0% 25%, white 0% 50%) 50% / 20px 20px;
}

.preview-label {
  text-align: center;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

/* File list before compression */
.file-list {
  margin-top: 16px;
}

.file-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  background: var(--bg);
  border-radius: 8px;
  margin-bottom: 8px;
}

.file-item-thumb {
  width: 36px;
  height: 36px;
  border-radius: 6px;
  object-fit: cover;
}

.file-item-name {
  flex: 1;
  font-size: 0.85rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-item-size {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.file-item-remove {
  width: 24px;
  height: 24px;
  border: none;
  background: none;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 1.1rem;
  border-radius: 4px;
}

.file-item-remove:hover {
  color: var(--danger);
  background: #fee2e2;
}