body {
    font-family: Arial, sans-serif;
    margin: 20px;
    background-color: #f8f8f8;
}
.nav a {
    margin-right: 15px;
}
.container {
    background: white;
    padding: 20px;
    border-radius: 8px;
}
.post, .comment {
    padding: 10px;
    margin: 10px 0;
    border-bottom: 1px solid #ccc;
}
.flash {
    padding: 10px;
    margin-bottom: 15px;
}
.flash.success {
    background-color: #d4edda;
}
.flash.danger {
    background-color: #f8d7da;
}