:root {
    --primary-color: #1f2937;
    --secondary-color: #6366f1;
    --success-color: #10b981;
    --danger-color: #ef4444;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f9fafb;
}

.navbar {
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
}

.navbar-brand {
    font-weight: bold;
    font-size: 1.5rem;
}

.card {
    border: none;
    border-radius: 0.5rem;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
}

.card-header {
    border-bottom: 2px solid rgba(0, 0, 0, 0.1);
    padding: 1.5rem;
}

footer {
    border-top: 1px solid #e5e7eb;
    margin-top: auto;
}

.btn {
    border-radius: 0.375rem;
    font-weight: 500;
}

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

.btn-primary:hover {
    background-color: #4f46e5;
    border-color: #4f46e5;
}

table {
    margin-bottom: 0;
}

th {
    font-weight: 600;
    border-bottom: 2px solid #e5e7eb;
}