body {
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100vh;
        margin: 0;
        background-color: #f5f7fb;
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    }
    .error-container {
        text-align: center;
        padding: 2rem;
    }
    .error-code {
        font-size: 4rem;
        font-weight: bold;
        color: #000;
        margin-bottom: 1rem;
    }
    .error-message {
        font-size: 1.5rem;
        color: #5f6b7a;
        margin-bottom: 2rem;
    }
    .back-link {
        color: #206bc4;
        text-decoration: none;
    }
    .back-link:hover {
        text-decoration: underline;
    }