body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f8f9fa;
    color: #333;
}

header {
    background-color: #2c3e50;
    color: white;
    padding: 1rem 0;
    text-align: center;
}

nav {
    background-color: #34495e;
    padding: 0.5rem;
    text-align: center;
}

nav a {
    color: white;
    text-decoration: none;
    margin: 0 15px;
    font-weight: bold;
}

nav a:hover {
    text-decoration: underline;
}

main {
    max-width: 900px;
    margin: 2rem auto;
    padding: 2rem;
    background: white;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    border-radius: 8px;
}

h1, h2 { color: #2c3e50; }

.status-box {
    padding: 10px;
    border-radius: 4px;
    margin-top: 20px;
    font-size: 0.9rem;
}

.success { background-color: #d4edda; color: #155724; border: 1px solid #c3e6cb; }
.error { background-color: #f8d7da; color: #721c24; border: 1px solid #f5c6cb; }