body {
    font-family: Arial, sans-serif;
    background: #f4f4f4;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: auto;
    background: white;
    padding: 20px;
    border-radius: 8px;
}

h1 {
    text-align: center;
    color: #333;
}

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

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

button, input[type="submit"] {
    background: #28a745;
    color: white;
    border: none;
    padding: 8px 15px;
    cursor: pointer;
    border-radius: 4px;
}

button.edit {
    background: #007bff;
}

button.delete {
    background: #dc3545;
}

form label {
    display: block;
    margin-top: 10px;
}

input, select {
    padding: 8px;
    width: 100%;
    margin-top: 5px;
}

.period {
    display: flex;
    gap: 10px;
    margin-top: 5px;
}

.period input {
    flex: 1;
}