body {
  margin: 0;
  font-family: "Noto Sans SC", "Microsoft YaHei", sans-serif;
  background: linear-gradient(90deg, #fff5f5 0%, #ffffff 20%, #ffffff 80%, #fff5f5 100%);
  color: #333;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 60px;
  border-bottom: 1px solid #eee;
  background: #fff;
  position: sticky;
  top: 0;
  z-index: 1000;
}

header .logo {
  display: flex;
  align-items: center;
  font-size: 16px;
  color: #333;
  cursor: pointer;
}

header .logo img {
  height: 50px;
  margin-right: 8px;
}

header nav a {
  color: #333;
  text-decoration: none;
  margin-left: 20px;
}

.page-shell {
  max-width: 1280px;
  margin: 0 auto;
  padding: 42px 24px 24px;
}

.container {
  display: grid;
  grid-template-columns: minmax(360px, 560px) minmax(420px, 1fr);
  gap: 36px;
  align-items: start;
}

.slider.single-image {
  width: 100%;
  height: clamp(360px, 33vw, 500px);
  border-radius: 18px;
  overflow: hidden;
  background: transparent;
  box-shadow: none;
  display: flex;
  align-items: center;
  justify-content: center;
}

.single-main-image {
  display: block;
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 18px;
}

.info {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: clamp(360px, 33vw, 500px);
  padding: 2px 0;
}

.info h1 {
  font-size: 28px;
  line-height: 1.2;
  margin: 0 0 12px;
  color: #1b1b1b;
}

.tags {
  display: flex;
  gap: 10px;
  margin-bottom: 14px;
}

.tag {
  background: #f6f6f6;
  color: #555;
  font-size: 14px;
  padding: 6px 12px;
  border-radius: 6px;
  line-height: 1;
}

.price-box {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.current-price {
  color: #ff4d00;
  font-size: 42px;
  font-weight: 800;
  line-height: 1;
}

.sold-count {
  color: #666;
  font-size: 15px;
}

.desc {
  color: #555;
  margin: 12px 0 18px;
  line-height: 1.65;
  font-size: 15px;
}

.option-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 10px;
}

.options.vertical {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.option {
  border: 1px solid #d7d7d7;
  border-radius: 10px;
  padding: 13px 16px;
  cursor: pointer;
  transition: .2s ease;
  font-size: 16px;
  background: #fff;
}

.option.active,
.option:hover {
  background: #fff7f5;
  color: #e85b35;
  border-color: #ff6a4d;
}

.buy-area {
  margin-top: 18px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  max-width: 520px;
}

.buy-row {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 16px;
}

.quantity-box {
  display: flex;
  align-items: center;
  border: 1px solid #ccc;
  border-radius: 8px;
  overflow: hidden;
  background: #fff;
}

.qty-btn,
.qty-input {
  width: 46px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.qty-btn {
  border: 0;
  background: #fff;
  cursor: pointer;
  font-size: 24px;
}

.qty-input {
  border-left: 1px solid #eee;
  border-right: 1px solid #eee;
  font-size: 20px;
}

.btn-buy {
  width: 100%;
  max-width: 520px;
  height: 56px;
  border: 0;
  border-radius: 10px;
  background: linear-gradient(180deg, #ff8e1a 0%, #ff5a00 100%);
  color: #fff;
  font-size: 18px;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 6px 14px rgba(255, 90, 0, 0.14);
}

.btn-buy:hover {
  filter: brightness(1.03);
}

.detail-section {
  max-width: 1320px;
  margin: 14px auto 50px;
  padding: 0 24px;
  text-align: center;
}

.detail-section h2 {
  font-size: 28px;
  margin-bottom: 18px;
}

.detail-frame {
  max-width: 1180px;
  margin: 0 auto;
  border-radius: 14px;
  overflow: hidden;
  box-shadow: 0 6px 18px rgba(0,0,0,0.08);
  background: #fff;
}

.detail-frame img {
  display: block;
  width: 100%;
  height: auto;
}

footer {
  text-align: center;
  color: #666;
  padding: 18px 0 28px;
}

.side-note {
  position: fixed;
  top: 50%;
  left: 24px;
  transform: translateY(-50%);
  z-index: 9999;
}

.note-tab {
  background-color: #f7f7f7;
  color: #444;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  letter-spacing: 2px;
  font-size: 16px;
  font-weight: 500;
  padding: 24px 12px;
  min-width: 46px;
  border-radius: 12px;
  border: 1px solid rgba(0,0,0,0.05);
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
  cursor: pointer;
  user-select: none;
}

.note-content {
  display: none;
  position: absolute;
  left: 62px;
  top: 0;
  width: 240px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.15);
  padding: 16px 18px;
}

.side-note:not(.collapsed) .note-content {
  display: block;
}

@media (max-width: 1100px) {
  .container {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .slider.single-image {
    max-width: 720px;
    margin: 0 auto;
    height: auto;
    min-height: 0;
  }

  .single-main-image {
    width: 100%;
    height: auto;
    max-height: none;
  }

  .info {
    min-height: 0;
  }
}

@media (max-width: 768px) {
  header {
    padding: 12px 18px;
  }

  .page-shell {
    padding: 24px 14px 20px;
  }

  .info h1 {
    font-size: 24px;
  }

  .current-price {
    font-size: 36px;
  }

  .option {
    font-size: 15px;
    padding: 12px 14px;
  }

  .btn-buy {
    height: 54px;
    font-size: 17px;
  }
}