body {
    font-family: Arial, sans-serif;
    background: #f4f6f9;
    margin: 0;
}

.sidebar {
    width: 230px;
    height: 100vh;
    background: #0b3c5d;
    color: #fff;
    position: fixed;
}

.sidebar h2 {
    text-align: center;
    padding: 15px;
    background: #072b42;
}

.sidebar a {
    display: block;
    color: #fff;
    padding: 12px;
    text-decoration: none;
}

.sidebar a:hover {
    background: #145c8a;
}

.main {
    margin-left: 230px;
    padding: 20px;
}

.card {
    background: #fff;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: 6px;
}

.btn {
    padding: 8px 14px;
    background: #0b3c5d;
    color: #fff;
    border: none;
    cursor: pointer;
    border-radius: 4px;
}

.btn-danger {
    background: #c0392b;
}

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

table th, table td {
    padding: 10px;
    border-bottom: 1px solid #ddd;
}