body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
    color: #222;
    background: #fff;
    line-height: 1.9;
}

#content {
    max-width: 760px;
    margin: 48px auto;
    padding: 0 20px;
}

h1 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
}

h2 {
    font-size: 1.4rem;
    margin-top: 3rem;
    margin-bottom: 1.5rem;
}

h3 {
    font-size: 1.1rem;
    margin-top: 2.5rem;
    margin-bottom: 0.8rem;
}

p {
    margin: 0 0 1.2rem 0;
}

hr {
    margin: 4rem 0;
    border: none;
    border-top: 1px solid #e0e0e0;
}