:root {
  /* Brand Colors */
  --color-primary: #002D72;     /* Metro Deep Blue */
  --color-primary-dark: #002050;
  --color-accent: #FFDD00;      /* Metro Yellow */
  --color-accent-hover: #e5c600;
  --color-alert: #D71920;       /* Discount Red */
  
  /* Neutrals */
  --color-bg: #F2F2F2;
  --color-surface: #FFFFFF;
  --color-text-main: #333333;
  --color-text-secondary: #666666;
  --color-border: #E0E0E0;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;

  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --weight-regular: 400;
  --weight-medium: 500;
  --weight-bold: 700;
  --weight-heavy: 800;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  --shadow-hover: 0 10px 25px rgba(0,45,114,0.15); /* Tinted subtle shadow */
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
}

body {
  font-family: var(--font-family);
  background-color: var(--color-bg);
  color: var(--color-text-main);
  margin: 0;
  padding: 0;
  line-height: 1.5;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  color: var(--color-primary);
  font-weight: var(--weight-heavy);
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

/* Layout */
.container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.main-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--spacing-lg);
  padding-top: var(--spacing-lg);
  padding-bottom: var(--spacing-xl);
}

/* Header */
.top-header {
  background-color: var(--color-primary);
  color: white;
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
}

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

.logo {
  background-color: var(--color-accent);
  color: var(--color-primary);
  padding: var(--spacing-xs) var(--spacing-md);
  font-weight: var(--weight-heavy);
  font-size: 1.5rem;
  letter-spacing: -0.5px;
  margin-right: var(--spacing-xl);
  border-radius: 2px;
}

.search-bar {
  flex: 1;
  max-width: 600px;
  position: relative;
}

.search-input {
  width: 100%;
  padding: 12px var(--spacing-md);
  border: none;
  border-radius: 4px;
  font-size: 1rem;
}

.search-input:focus {
  outline: 2px solid var(--color-accent);
}

.header-actions {
  display: flex;
  gap: var(--spacing-lg);
  align-items: center;
}

.cart-icon-wrapper {
  position: relative;
  color: white;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-weight: var(--weight-medium);
  cursor: pointer;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: 4px;
  transition: background-color var(--transition-fast);
}

.cart-icon-wrapper:hover {
  background-color: rgba(255,255,255,0.1);
}

.cart-badge {
  position: absolute;
  top: 0;
  right: 0;
  background-color: var(--color-accent);
  color: var(--color-primary);
  font-size: 0.75rem;
  font-weight: var(--weight-bold);
  height: 20px;
  width: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transform: translate(25%, -25%);
}

/* Sidebar Navigation */
.sidebar {
  background-color: var(--color-surface);
  border-radius: 8px;
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  height: fit-content;
}

.category-title {
  font-size: 1.1rem;
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--color-accent);
}

.category-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.category-item {
  cursor: pointer;
}

.category-link {
  display: block;
  padding: var(--spacing-sm);
  border-radius: 4px;
  color: var(--color-text-main);
  transition: all var(--transition-fast);
  font-weight: var(--weight-medium);
}

.category-link:hover {
  background-color: var(--color-bg);
  color: var(--color-primary);
}

.category-link.active {
  background-color: var(--color-primary);
  color: white;
}

.sub-category-list {
  margin-left: var(--spacing-md);
  border-left: 2px solid var(--color-border);
  padding-left: var(--spacing-sm);
  display: none;
}

.sub-category-list.open {
  display: block;
  animation: slideDown 0.3s ease-out;
}

/* Products Grid */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing-md);
}

.product-card {
  background-color: var(--color-surface);
  border-radius: 8px;
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  border: 1px solid transparent;
  position: relative;
  overflow: hidden;
}

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

.product-image-container {
  height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--spacing-md);
  background-color: white;
}

.product-image {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  transition: transform var(--transition-normal);
}

.product-card:hover .product-image {
  transform: scale(1.05);
}

.product-info {
  flex: 1;
  display: flex;
  flex-direction: column;
}

.product-category {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: var(--spacing-xs);
}

.product-title {
  font-size: 1rem;
  line-height: 1.4;
  margin-bottom: var(--spacing-sm);
  color: var(--color-primary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.price-container {
  margin-top: auto;
  border-top: 1px solid var(--color-border);
  padding-top: var(--spacing-sm);
}

.price-net {
  font-size: 1.5rem;
  font-weight: var(--weight-heavy);
  color: var(--color-text-main);
}

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

.btn-add {
  margin-top: var(--spacing-md);
  background-color: var(--color-primary);
  color: white;
  border: none;
  padding: 10px;
  width: 100%;
  border-radius: 4px;
  font-weight: var(--weight-bold);
  cursor: pointer;
  transition: background-color var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
}

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

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

/* Status Badges */
.status-badge {
  position: absolute;
  top: var(--spacing-sm);
  right: var(--spacing-sm);
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: var(--weight-bold);
}

.status-available {
  background-color: #E6F4EA;
  color: #1E8E3E;
}

.status-unavailable {
  background-color: #FCE8E6;
  color: #C5221F;
}

/* Animations */
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Product Detail Page Specifics */
.product-detail-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
  background: white;
  padding: var(--spacing-xl);
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
}

.detail-image-area {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-lg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
}

.detail-info-area h1 {
  font-size: 2rem;
  margin-bottom: var(--spacing-md);
  color: var(--color-primary);
}

.detail-price-block {
  background-color: var(--color-bg);
  padding: var(--spacing-md);
  border-radius: 8px;
  margin: var(--spacing-lg) 0;
}

/* Cart Page Specifics */
.cart-layout {
  display: grid;
  grid-template-columns: 1fr 350px;
  gap: var(--spacing-lg);
}

.cart-items {
  background: white;
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.cart-item {
  display: grid;
  grid-template-columns: 100px 1fr auto auto;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
  align-items: center;
}

.cart-summary {
  background: white;
  padding: var(--spacing-lg);
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
  height: fit-content;
}

.summary-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--spacing-sm);
}

.summary-total {
  border-top: 2px solid var(--color-border);
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  font-weight: var(--weight-heavy);
  font-size: 1.25rem;
  color: var(--color-primary);
}

.btn-checkout {
  background-color: var(--color-accent);
  color: var(--color-primary);
  width: 100%;
  padding: var(--spacing-md);
  border: none;
  border-radius: 4px;
  font-weight: var(--weight-heavy);
  font-size: 1.1rem;
  margin-top: var(--spacing-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-checkout:hover {
  background-color: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Responsive */
@media (max-width: 1024px) {
  .main-layout {
    grid-template-columns: 240px 1fr;
  }
}

@media (max-width: 768px) {
  .main-layout {
    grid-template-columns: 1fr;
  }
  
  .sidebar {
    display: none; /* Mobile handling needed later */
  }
  
  .product-detail-layout {
    grid-template-columns: 1fr;
  }
  
  .cart-layout {
    grid-template-columns: 1fr;
  }
}