body {
    font-family: system-ui, sans-serif;
    max-width: 700px;
    margin: 40px auto;
    padding: 0 20px;
    background: #fafafa;
    color: #222;
}

h1 { font-size: 20px; font-weight: 600; margin-bottom: 16px; }

#hint {
    margin-top: 24px;
    font-size: 12px;
    color: #888;
    line-height: 1.6;
}

kbd {
    background: #eee;
    border: 1px solid #ccc;
    border-radius: 3px;
    padding: 1px 5px;
    font-size: 11px;
    font-family: monospace;
}