/* Core Styles */
:root {
    --primary: #2e7d32;
    --primary-dark: #1b5e20;
    --primary-light: #4caf50;
    --secondary: #ff9800;
    --danger: #d32f2f;
    --warning: #ffa000;
    --success: #388e3c;
    --gray-100: #f8f9fa;
    --gray-200: #e9ecef;
    --gray-300: #dee2e6;
    --gray-600: #6c757d;
    --gray-800: #343a40;
    --white: #ffffff;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --border-radius: 8px;
}

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

body {
    padding-top: 80px; 
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--gray-100);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Navigation */
.header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary);
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray-800);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary);
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    transition: all 0.3s;
}

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

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

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

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

/* Cards */
.card {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.product-card {
    transition: transform 0.3s;
    cursor: pointer;
}

.product-card:hover {
    transform: translateY(-5px);
}

.product-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--border-radius);
}

.product-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0.5rem 0;
}

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

.product-seller {
    color: var(--gray-600);
    font-size: 0.9rem;
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--gray-300);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-control:focus {
    border-color: #28a745;
    box-shadow: 0 0 0 0.2rem rgba(40, 167, 69, 0.25);
}
/* Alerts */
.alert {
    padding: 1rem;
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
}

.alert-success {
    background: #d4edda;
    color: var(--success);
    border: 1px solid #c3e6cb;
}

.alert-error {
    background: #f8d7da;
    color: var(--danger);
    border: 1px solid #f5c6cb;
}

/* Grid */
.grid {
    display: grid;
    gap: 1.5rem;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.hidden { display: none; }

/* Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-success { background: var(--success); color: white; }
.badge-warning { background: var(--warning); color: white; }
.badge-danger { background: var(--danger); color: white; }