:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --success: #22c55e;
    --danger: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    --bg: #f8fafc;
    --card: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1);
}

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

body {
    font-family: 'Segoe UI', system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 260px;
    height: 100vh;
    background: var(--card);
    border-right: 1px solid var(--border);
    padding: 1.5rem;
    overflow-y: auto;
}

.logo {
    width: 100%;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.logo img{
    width: 60px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1rem;
    border-radius: 0.5rem;
    color: var(--text-muted);
    text-decoration: none;
    margin-bottom: 0.25rem;
    transition: all 0.2s;
}

.nav-item:hover, .nav-item.active {
    background: var(--primary);
    color: white;
}

.nav-item i { width: 20px; text-align: center; }

.main-content {
    margin-left: 260px;
    padding: 2rem;
    min-height: 100vh;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.page-title {
    font-size: 1.875rem;
    font-weight: 700;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: 0.5rem;
    border: none;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

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

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

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--card);
    padding: 1.5rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.stat-card .label {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.stat-card .value {
    font-size: 1.875rem;
    font-weight: 700;
}

.stat-card .trend {
    font-size: 0.75rem;
    margin-top: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.trend-up { color: var(--success); }
.trend-down { color: var(--danger); }

.card {
    background: var(--card);
    border-radius: 1rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    overflow: hidden;
}

.card-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-title {
    font-size: 1.125rem;
    font-weight: 600;
}

.card-body { padding: 1.5rem; }

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th, .table td {
    padding: 0.875rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.table th {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    background: var(--bg);
}

.table tr:hover { background: var(--bg); }

.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-danger { background: #fee2e2; color: #991b1b; }

.stock-bar {
    width: 100%;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
    margin-top: 0.25rem;
}

.stock-fill {
    height: 100%;
    border-radius: 3px;
    transition: width 0.3s;
}

.stock-high { background: var(--success); }
.stock-medium { background: var(--warning); }
.stock-low { background: var(--danger); }

.search-box {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
    width: 300px;
}

.search-box input {
    border: none;
    background: none;
    outline: none;
    width: 100%;
    font-size: 0.875rem;
}

.form-group { margin-bottom: 1.25rem; }

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.form-input, .form-select {
    width: 100%;
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-size: 0.875rem;
    transition: border-color 0.2s;
}

.form-input:focus, .form-select:focus {
    outline: none;
    border-color: var(--primary);
}

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

.price-input {
    position: relative;
}

.price-input::before {
    content: '$';
    position: absolute;
    left: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.price-input input { padding-left: 1.75rem; }

.profit-display {
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    padding: 1rem;
    border-radius: 0.5rem;
    margin-top: 1rem;
}

.profit-display .amount {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--success);
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 100;
}

.modal-overlay.active { display: flex; }

.modal {
    background: var(--card);
    border-radius: 1rem;
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 25px 50px -12px rgb(0 0 0 / 0.25);
}

.modal-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-body { padding: 1.5rem; }

.close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-muted);
}

.alert {
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    display: none;
}

.alert-success { background: #dcfce7; color: #166534; border: 1px solid #bbf7d0; }
.alert-error { background: #fee2e2; color: #991b1b; border: 1px solid #fecaca; }

.low-stock-alert {
    background: #fef3c7;
    border: 1px solid #fde68a;
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

@media (max-width: 768px) {
    .sidebar { width: 100%; position: relative; height: auto; }
    .main-content { margin-left: 0; }
    .stats-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
}