/* Light Theme */
:root {
    --background-color: #f4f4f4;
    --text-color: #333;
    --container-background: #fff;
    --header-color: #4CAF50;
    --header-text: #fff;
    --button-background: #4CAF50;
    --button-text: #fff;
    --button-hover-background: #45a049;
    --content-background: #fff;
    --table-border: #ddd;
    --row-background: #f9f9f9;
    --row-hover-background: #f1f1f1;
    --error-color: #f44336;
}

/* Dark Theme */
body.dark-mode {
    --background-color: #121212;
    --text-color: #e0e0e0;
    --container-background: #1e1e1e;
    --header-color: #bb86fc;
    --header-text: #000;
    --button-background: #333;
    --button-text: #e0e0e0;
    --button-hover-background: #555;
    --content-background: #1e1e1e;
    --table-border: #444;
    --row-background: #1a1a1a;
    --row-hover-background: #333;
    --error-color: #cf6679;
}

body {
    font-family: 'Arial', sans-serif;
    background-color: #f4f4f4;
    margin: 0;
    padding: 0;
    color: #333;
}

.container {
    width: 80%;
    margin: 0 auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    color: #4CAF50;
}

h2 {
    border-bottom: 2px solid #4CAF50;
    padding-bottom: 10px;
    color: #4CAF50;
}

form {
    margin-bottom: 20px;
}

form label {
    margin-right: 10px;
}

form input[type="text"] {
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
    margin-right: 10px;
    width: 200px;
}

form button {
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    background-color: #4CAF50;
    color: #fff;
    cursor: pointer;
    transition: background-color 0.3s;
}

form button:hover {
    background-color: #45a049;
}

.error {
    color: #f44336;
    text-align: center;
    font-weight: bold;
    margin-bottom: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

table th, table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

table th {
    background-color: #4CAF50;
    color: white;
}

table tr:nth-child(even) {
    background-color: #f2f2f2;
}

table tr:hover {
    background-color: #ddd;
}

table td {
    border-radius: 4px;
}