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

:root {
  --primary: #667eea;
  --primary-dark: #764ba2;
  --success: #10b981;
  --danger: #ef4444;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-900: #111827;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--gray-50);
  color: var(--gray-900);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.header {
  background: white;
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--primary);
}

.logo h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--gray-900);
}

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

.btn-upload {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: var(--gray-100);
  border: 1px solid var(--gray-200);
  border-radius: 10px;
  font-size: 14px;
  font-weight: 500;
  color: var(--gray-700);
  cursor: pointer;
  transition: all 0.2s;
}

.btn-upload:hover {
  background: var(--gray-200);
}

.main {
  flex: 1;
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
  padding: 24px;
}

.upload-area {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 400px;
  border: 3px dashed var(--gray-300);
  border-radius: 20px;
  background: white;
  cursor: pointer;
  transition: all 0.3s;
}

.upload-area:hover,
.upload-area.dragover {
  border-color: var(--primary);
  background: rgba(102, 126, 234, 0.05);
}

.upload-content {
  text-align: center;
  padding: 40px;
}

.upload-content svg {
  color: var(--gray-400);
  margin-bottom: 20px;
}

.upload-content h2 {
  font-size: 24px;
  color: var(--gray-700);
  margin-bottom: 8px;
}

.upload-content p {
  color: var(--gray-500);
  margin-bottom: 8px;
}

.upload-hint {
  font-size: 13px;
  color: var(--gray-400);
  margin-top: 16px;
}

.products-container {
  animation: fadeIn 0.3s ease;
}

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

.products-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--gray-200);
}

.products-count {
  font-size: 16px;
  color: var(--gray-600);
}

.products-count span {
  font-weight: 700;
  color: var(--primary);
  font-size: 20px;
}

.products-sort select {
  padding: 10px 16px;
  border: 1px solid var(--gray-200);
  border-radius: 8px;
  font-size: 14px;
  background: white;
  cursor: pointer;
}

.products-sort select:focus {
  outline: none;
  border-color: var(--primary);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

.product-card {
  background: white;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.product-images {
  position: relative;
}

.product-main-image {
  width: 100%;
  height: 350px;
  object-fit: cover;
  background: var(--gray-100);
}

.product-thumbs {
  display: flex;
  gap: 8px;
  padding: 12px;
  overflow-x: auto;
}

.product-thumb {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: 8px;
  cursor: pointer;
  border: 2px solid transparent;
  transition: border-color 0.2s;
  flex-shrink: 0;
}

.product-thumb:hover,
.product-thumb.active {
  border-color: var(--primary);
}

.product-info {
  padding: 20px;
}

.product-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--gray-900);
  margin-bottom: 6px;
  line-height: 1.4;
}

.product-title-vi {
  font-size: 13px;
  color: var(--gray-500);
  font-style: italic;
  margin-bottom: 12px;
  line-height: 1.4;
}

.product-prices {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
}

.product-price-vnd {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
}

.product-price-eur {
  font-size: 14px;
  color: var(--gray-500);
  text-decoration: line-through;
}

.product-sizes {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.size-tag {
  padding: 6px 14px;
  background: var(--gray-100);
  border-radius: 20px;
  font-size: 12px;
  color: var(--gray-700);
  font-weight: 500;
}

.footer {
  background: white;
  border-top: 1px solid var(--gray-200);
  padding: 24px;
  text-align: center;
}

.footer p {
  color: var(--gray-500);
  font-size: 14px;
}

@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    gap: 16px;
  }

  .products-grid {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 16px;
  }

  .product-main-image {
    height: 280px;
  }
}