/* =========================================================
   E-Commerce Platform — Global Stylesheet
   Single accent color: indigo (#4F46E5)
   ========================================================= */

:root {
  --accent: #4F46E5;
  --accent-dark: #4338CA;
  --accent-light: #EEF2FF;
  --text-primary: #111827;
  --text-secondary: #6B7280;
  --bg-page: #F9FAFB;
  --bg-card: #FFFFFF;
  --border-color: #E5E7EB;
  --danger: #DC2626;
  --success: #16A34A;
  --radius: 10px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --max-width: 1200px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.5;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; margin: 0; padding: 0; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Header ---------- */
.site-header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-primary);
}

.logo .accent { color: var(--accent); }

.main-nav { display: flex; align-items: center; gap: 24px; }

.nav-link {
  font-weight: 500;
  color: var(--text-secondary);
  padding: 8px 4px;
  border-bottom: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}

.nav-link:hover, .nav-link.active { color: var(--accent); border-color: var(--accent); }

.cart-link { display: flex; align-items: center; gap: 6px; }

.cart-badge {
  background: var(--accent);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  min-width: 20px;
  height: 20px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 5px;
}

/* ---------- Hero / Toolbar ---------- */
.hero { padding: 40px 0 24px; text-align: center; }
.hero h1 { font-size: 2rem; margin: 0 0 8px; }
.hero p { color: var(--text-secondary); margin: 0; }

.toolbar {
  display: flex;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.search-input, .category-select {
  padding: 10px 14px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  font-size: 0.95rem;
  background: var(--bg-card);
}

.search-input { flex: 1; min-width: 200px; }
.category-select { min-width: 160px; }

.search-input:focus, .category-select:focus, input:focus, select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

/* ---------- Product Grid ---------- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: 20px;
  padding-bottom: 60px;
}

.product-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s, box-shadow 0.15s;
  display: flex;
  flex-direction: column;
}

.product-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }

.product-card-link { color: inherit; display: block; }

.product-image-wrap { width: 100%; aspect-ratio: 1/1; overflow: hidden; background: var(--accent-light); }
.product-image-wrap img { width: 100%; height: 100%; object-fit: cover; display: block; }

.product-card-body { padding: 14px 16px 4px; }

.product-category {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  font-weight: 700;
}

.product-name { font-size: 1rem; margin: 6px 0 4px; font-weight: 600; }
.product-price { font-weight: 700; color: var(--text-primary); margin: 0 0 8px; }

.empty-state { text-align: center; color: var(--text-secondary); padding: 60px 0; grid-column: 1/-1; }
.empty-state a { color: var(--accent); font-weight: 600; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: none;
  cursor: pointer;
  border-radius: var(--radius);
  font-weight: 600;
  transition: background 0.15s, transform 0.1s;
  text-align: center;
}

.btn:active { transform: scale(0.98); }

.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); }

.btn-sm { padding: 8px 12px; font-size: 0.85rem; margin: 0 16px 16px; width: calc(100% - 32px); }
.btn-lg { padding: 14px 20px; font-size: 1rem; width: 100%; margin-top: 8px; }
.full-width { width: 100%; }

.back-link {
  display: inline-block;
  margin-top: 16px;
  color: var(--accent);
  font-weight: 600;
}

/* ---------- Product Detail Page ---------- */
.product-detail-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  padding: 40px 0 60px;
}

.product-detail-image {
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--accent-light);
  aspect-ratio: 1/1;
}

.product-detail-image img { width: 100%; height: 100%; object-fit: cover; display: block; }

.product-detail-info h1 { font-size: 1.8rem; margin: 8px 0 4px; }
.product-detail-price { font-size: 1.5rem; font-weight: 800; color: var(--accent); margin: 0 0 16px; }
.product-detail-desc { color: var(--text-secondary); margin-bottom: 12px; }
.stock-note { font-size: 0.85rem; color: var(--success); margin-bottom: 20px; }

.qty-selector { margin-bottom: 20px; }
.qty-selector label { display: block; font-weight: 600; margin-bottom: 8px; }

.qty-controls { display: flex; align-items: center; gap: 8px; }

.qty-btn {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  cursor: pointer;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.qty-btn:hover { border-color: var(--accent); color: var(--accent); }

#qty-input, .cart-qty-input {
  width: 54px;
  height: 36px;
  text-align: center;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.95rem;
}

/* ---------- Cart Page ---------- */
.cart-layout { display: grid; grid-template-columns: 2fr 1fr; gap: 32px; padding: 32px 0 60px; align-items: start; }

.page-title { margin: 32px 0 8px; font-size: 1.8rem; }

.cart-table { width: 100%; border-collapse: collapse; background: var(--bg-card); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); }
.cart-table th, .cart-table td { padding: 14px 16px; text-align: left; border-bottom: 1px solid var(--border-color); font-size: 0.9rem; }
.cart-table th { color: var(--text-secondary); font-weight: 600; text-transform: uppercase; font-size: 0.75rem; letter-spacing: 0.04em; }

.cart-product-cell { display: flex; align-items: center; gap: 12px; font-weight: 600; }
.cart-product-cell img { width: 48px; height: 48px; object-fit: cover; border-radius: 8px; }

.remove-btn {
  background: none;
  border: none;
  color: var(--danger);
  font-size: 1rem;
  cursor: pointer;
  padding: 6px;
}
.remove-btn:hover { text-decoration: underline; }

.empty-cart { text-align: center; padding: 60px 20px; background: var(--bg-card); border-radius: var(--radius); border: 1px solid var(--border-color); }
.empty-cart p { color: var(--text-secondary); margin-bottom: 16px; }
.empty-cart .btn { display: inline-flex; padding: 12px 24px; }

/* ---------- Order Summary (shared: cart + checkout + confirmation) ---------- */
.order-summary {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  align-self: start;
}

.order-summary h2 { margin: 0 0 16px; font-size: 1.1rem; }

.summary-items { margin-bottom: 12px; }
.summary-items li {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.summary-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  font-size: 0.95rem;
}

.summary-total {
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--text-primary);
  border-top: 1px solid var(--border-color);
  margin-top: 8px;
  padding-top: 12px;
}

.checkout-btn { display: flex; margin-top: 16px; }

/* ---------- Checkout Page ---------- */
.checkout-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 32px; padding: 24px 0 60px; align-items: start; }

.checkout-form {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.checkout-form fieldset { border: none; padding: 0; margin: 0 0 24px; }
.checkout-form legend { font-weight: 700; font-size: 1.05rem; margin-bottom: 12px; padding: 0; }
.demo-note { font-size: 0.75rem; color: var(--text-secondary); font-weight: 400; }

.checkout-form label { display: block; font-size: 0.85rem; font-weight: 600; margin: 12px 0 6px; }

.checkout-form input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.95rem;
}

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* ---------- Confirmation Page ---------- */
.confirmation-container { max-width: 560px; margin: 0 auto; padding: 60px 0; text-align: center; }

.confirmation-check {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
}

.confirmation-sub { color: var(--text-secondary); margin-bottom: 28px; }

.order-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 24px;
  text-align: left;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.order-card hr { border: none; border-top: 1px solid var(--border-color); margin: 12px 0; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--border-color); padding: 24px 0; margin-top: auto; }
.site-footer p { color: var(--text-secondary); font-size: 0.85rem; text-align: center; margin: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .product-detail-grid, .cart-layout, .checkout-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .header-inner { height: 56px; }
  .hero h1 { font-size: 1.5rem; }
  .product-grid { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 14px; }
  .btn-sm { margin: 0 12px 12px; width: calc(100% - 24px); }
}