:root {
    --primary-color: #007bff;
    --secondary-color: #28a745;
    --warning-color: #dc3545;
    --background-color: #f0f4f8;
    --text-color: #343a40;
    --card-bg: white;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    padding: 20px;
    min-height: 100vh;
}

.app-container {
    max-width: 1200px;
    width: 100%;
}

.header {
    text-align: center;
    padding: 20px 0;
    margin-bottom: 30px;
}

.header h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.subtitle {
    color: #6c757d;
    font-size: 1rem;
}

.main-content {
    display: grid;
    gap: 30px;
    grid-template-columns: 2fr 1fr;
}

.card {
    background: var(--card-bg);
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    height: fit-content;
}

h2 {
    color: var(--text-color);
    border-bottom: 2px solid #e9ecef;
    padding-bottom: 8px;
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.grid-layout {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 20px;
}

.product-card {
    border: 1px solid #dee2e6;
    padding: 15px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    transition: transform 0.2s;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
}

.product-card strong {
    font-size: 1.2em;
    margin-bottom: 5px;
}

.product-card .price {
    color: var(--secondary-color);
    font-weight: bold;
    margin-bottom: 15px;
    font-size: 1.1em;
}

.product-card button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px;
    border-radius: 5px;
    cursor: pointer;
    margin-top: auto;
}

.cart-items-list {
    min-height: 50px;
    margin-bottom: 20px;
}

.cart-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed #e9ecef;
}

.item-info {
    flex-grow: 1;
}

.item-name {
    font-weight: 600;
    font-size: 1em;
}

.item-price {
    font-size: 0.85em;
    color: #6c757d;
}

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

.item-controls button {
    background: #f8f9fa;
    border: 1px solid #ced4da;
    color: var(--text-color);
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
}

.cart-summary {
    padding-top: 15px;
    border-top: 2px solid var(--primary-color);
}

.summary-line {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
}

.total-line {
    font-size: 1.3em;
    color: var(--warning-color);
    padding-top: 10px;
    border-top: 1px dashed #ced4da;
}

.checkout-button {
    width: 100%;
    background-color: var(--secondary-color);
    margin-top: 20px;
    color: white;
    font-size: 1.1rem;
    padding: 12px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

.checkout-button:hover {
    background-color: #1e7e34;
}

@media (max-width: 768px) {
    .main-content {
        grid-template-columns: 1fr;
    }
    .grid-layout {
        grid-template-columns: 1fr;
    }
}