body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f9f9f9;
}
nav {
    background-color: #2c3e50;
    color: white;
    padding: 1em;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
nav .nav-left {
    font-weight: bold;
}
nav .nav-right a {
    color: white;
    margin-left: 1em;
    text-decoration: none;
}
.container {
    padding: 2em;
}
.sidebar {
    display: flex;
    justify-content: space-between;
    margin: 1em 0;
}
.sidebar .left,
.sidebar .right {
    width: 20%;
    background: #fff;
    padding: 1em;
    border-radius: 8px;
    box-shadow: 0 0 5px rgba(0,0,0,0.1);
}