:root {
    --primary-color: #4f46e5; /* Indigo 600 */
    --primary-hover: #4338ca; /* Indigo 700 */
    --secondary-color: #1e293b; /* Slate 800 */
    --bg-color: #f8fafc; /* Slate 50 */
    --card-bg: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --radius: 0.75rem;
    --shadow-sm: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    letter-spacing: -0.025em;
    color: var(--secondary-color);
}

/* --- Navbar --- */
.navbar {
    background-color: #ffffff !important;
    box-shadow: var(--shadow-sm);
    padding-top: 1rem;
    padding-bottom: 1rem;
}

.navbar-brand {
    font-weight: 800;
    color: var(--primary-color) !important;
    font-size: 1.5rem;
    letter-spacing: -0.05em;
}

.nav-link {
    font-weight: 500;
    color: var(--secondary-color) !important;
    transition: color 0.2s;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary-color) !important;
}

.badge-cart {
    background-color: var(--primary-color);
    color: white;
}

/* --- Hero Section --- */
.hero-section {
    background: linear-gradient(135deg, #4f46e5 0%, #818cf8 100%);
    color: white;
    padding: 5rem 0;
    border-radius: 0 0 2rem 2rem;
    margin-bottom: 3rem;
}

.hero-section h1 {
    color: white;
}

.hero-section .lead {
    color: #e0e7ff;
}

/* --- Cards --- */
.card {
    border: none;
    border-radius: var(--radius);
    background: var(--card-bg);
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.card-img-top {
    height: 220px;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.card:hover .card-img-top {
    transform: scale(1.05);
}

.card-title {
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.card-price {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
}

/* --- Buttons --- */
.btn {
    border-radius: 0.5rem;
    padding: 0.6rem 1.2rem;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    box-shadow: 0 4px 6px -1px rgba(79, 70, 229, 0.4);
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    border-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 6px 8px -1px rgba(79, 70, 229, 0.5);
}

.btn-outline-primary {
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline-primary:hover {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

/* --- Sidebar / List Groups --- */
.list-group-item {
    border: none;
    margin-bottom: 5px;
    border-radius: 0.5rem !important;
    transition: all 0.2s;
    color: var(--text-muted);
}

.list-group-item:hover {
    background-color: #eff6ff;
    color: var(--primary-color);
    padding-left: 1.5rem; /* Slide effect */
}

.list-group-item.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

/* --- Footer --- */
footer {
    background-color: var(--secondary-color) !important;
    margin-top: auto;
    padding: 3rem 0;
}

footer a {
    color: #cbd5e1;
    transition: color 0.2s;
}

footer a:hover {
    color: white;
}

/* --- Form Controls --- */
.form-control, .form-select {
    border-radius: 0.5rem;
    border: 1px solid #e2e8f0;
    padding: 0.75rem 1rem;
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

/* Badge overlap on cards */
.badge-category {
    background: rgba(255, 255, 255, 0.9);
    color: var(--text-main);
    font-weight: 600;
    backdrop-filter: blur(4px);
    box-shadow: var(--shadow-sm);
}