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

header {
    background: #4CAF50;
    color: white;
    padding: 15px;
    text-align: center;
}

nav {
    background: #333;
    display: flex;
    justify-content: center;
}

nav a {
    color: white;
    padding: 14px 20px;
    text-decoration: none;
    transition: background 0.3s;
}

nav a:hover {
    background: #575757;
}

.container {
    max-width: 1000px;
    margin: 20px auto;
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px #ccc;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 15px;
}

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

table th {
    background: #eee;
}

.btn {
    text-decoration: none;
    padding: 6px 12px;
    border-radius: 4px;
    color: white;
    background: #2196F3;
    margin: 2px;
}

.btn-danger {
    background: #f44336;
}

.btn-success {
    background: #4CAF50;
}