* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  color: #111;
  background: #fff;
}

.product-page {
  max-width: 1400px;
  margin: 0 auto;
  padding: 70px 32px 90px;
}

.product-main {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  margin-top: 20px;
}

.product-gallery {
  width: 100%;
}

.product-image-box {
  background: #f3f3f3;
  border-radius: 28px;
  min-height: 680px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px;
}

.product-main-image {
  width: 100%;
  max-width: 520px;
  max-height: 600px;
  object-fit: contain;
  display: block;
}

.product-details {
  padding-top: 10px;
}

.product-vendor {
  font-size: 0.9rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #777;
  margin: 0 0 18px;
}

.product-name {
  font-size: clamp(2.4rem, 4vw, 4rem);
  line-height: 1.02;
  margin: 0 0 18px;
  font-weight: 700;
}

.product-price-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
  flex-wrap: wrap;
}

.product-old-price {
  color: #888;
  text-decoration: line-through;
  font-size: 1.05rem;
}

.product-price {
  color: #111;
  font-size: 1.6rem;
  font-weight: 700;
}

.product-stock {
  margin: 0 0 28px;
  font-size: 1.05rem;
  font-weight: 600;
}

.product-stock.in-stock {
  color: #1f7a35;
}

.product-stock.out-of-stock {
  color: #b42318;
}

.product-actions {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 30px;
}

.btn-add-cart,
.btn-buy-now {
  width: 100%;
  border: none;
  border-radius: 14px;
  padding: 17px 20px;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition:
    transform 0.2s ease,
    opacity 0.2s ease;
}

.btn-add-cart {
  background: #111;
  color: #fff;
}

.btn-buy-now {
  background: #f2f2f2;
  color: #111;
}

.btn-add-cart:hover,
.btn-buy-now:hover {
  transform: translateY(-1px);
  opacity: 0.92;
}

.product-extra {
  border-top: 1px solid #e8e8e8;
  padding-top: 18px;
  display: grid;
  gap: 12px;
}

.product-extra-item {
  display: flex;
  gap: 8px;
  font-size: 1rem;
  color: #444;
}

.product-extra-item .label {
  font-weight: 700;
  color: #111;
}

.related-products-section {
  margin-top: 95px;
}

.related-header h2 {
  font-size: 2.1rem;
  margin: 0 0 30px;
}

.related-products-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(220px, 1fr));
  gap: 24px;
}

.related-card {
  display: block;
  text-decoration: none;
  color: inherit;
  background: #f4f4f4;
  border: 1px solid rgba(0, 0, 0, 0.14);
  border-radius: 24px;
  overflow: hidden;
  transition:
    transform 0.25s ease,
    box-shadow 0.25s ease;
}

.related-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 16px 28px rgba(0, 0, 0, 0.08);
}

.related-image-wrap {
  position: relative;
  background: #ececec;
  aspect-ratio: 1 / 1.2;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.related-badge {
  position: absolute;
  top: 16px;
  left: 16px;
  background: #4d74db;
  color: #fff;
  padding: 8px 14px;
  font-size: 0.8rem;
  border-radius: 999px;
  z-index: 2;
}

.related-image {
  width: 80%;
  height: 80%;
  object-fit: contain;
  display: block;
}

.related-info {
  padding: 20px;
}

.related-title {
  margin: 0 0 12px;
  font-size: 1.05rem;
  line-height: 1.25;
  color: #111;
}

.related-price-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.related-old-price {
  color: #888;
  text-decoration: line-through;
  font-size: 0.95rem;
}

.related-price {
  color: #111;
  font-weight: 700;
  font-size: 1rem;
}

@media (max-width: 1100px) {
  .product-main {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .product-image-box {
    min-height: 520px;
  }

  .related-products-grid {
    grid-template-columns: repeat(2, minmax(220px, 1fr));
  }
}

@media (max-width: 640px) {
  .product-page {
    padding: 28px 16px 50px;
  }

  .product-main {
    gap: 24px;
    margin-top: 10px;
  }

  .product-image-box {
    min-height: 360px;
    padding: 24px;
    border-radius: 20px;
  }

  .product-name {
    font-size: 2.2rem;
  }

  .related-products-grid {
    grid-template-columns: 1fr;
  }

  .related-header h2 {
    font-size: 1.6rem;
  }
}

.product-sizes {
  margin-bottom: 24px;
}

.sizes-label {
  font-size: 0.95rem;
  color: #666;
  margin: 0 0 12px;
}

.sizes-options {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.size-btn {
  min-width: 74px;
  height: 44px;
  border: 1px solid #222;
  background: #fff;
  color: #111;
  font-size: 1rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.size-btn.active {
  background: #111;
  color: #fff;
}

.size-btn:hover {
  opacity: 0.9;
}