body {
            font-family: 'Noto Serif JP', serif;
            color: #333;
            background-color: #f4f4f4;
            padding: 20px;
            line-height: 1.8;
            margin: 0;
    font-size: 110%; /* ←追加 */
        }
        .container {
            max-width: 700px;
            margin: 0 auto;
            background-color: #ffffff;
            padding: 40px;
            border-radius: 10px;
            box-shadow: 0 8px 15px rgba(0,0,0,0.1);
        }
.main-title {
    font-size: 1.6em;
    font-weight: normal;
    color: #777;
}

.sub-title {
    font-size: 2.2em;
    font-weight: bold;
    margin-top: 5px;
    color: #333;
}


.date-title {
    font-size: 1.0em;
}

p {
    line-height: 2.0;
    margin-bottom: 1.8em;
}

blockquote {
    margin: 1.8em 0;
    padding: 10px 20px;
    border-left: 4px solid #ccc;
    color: #555;
    font-style: italic;
    background-color: #f9f9f9;
}

.author {
    text-align: right;
    margin-top: 25px;
    font-weight: normal;
    font-size: 1em;
    color: #666;
    font-style: italic;
}

        .header-content {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-bottom: 30px;
        }
.header-content img {
    max-width: 45%;
    border-radius: 8px;
    margin-right: 15px;
}
        .header-text {
            flex: 1;
            margin-left: 25px;
        }
        .content-image {
            width: 100%;
            max-width: 500px;
            display: block;
            margin: 60px auto;
            border-radius: 8px;
        }
        .copyright {
            text-align: center;
            font-size: 0.9em;
            color: #aaa;
            margin-top: 40px;
        }
@media (max-width: 600px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }
    .header-content img {
        max-width: 100%;
        margin-bottom: 15px;
    }
    .header-text {
        margin-left: 0;
    }
    .author {
        text-align: center;
    }

    /* ここから追加 */
    .main-title,
    .sub-title {
        word-break: keep-all; /* 改行を制御して自然に */
    }

    .main-title {
        font-size: 1.4em; /* スマホ時に少し小さく調整 */
    }

    .sub-title {
        font-size: 1.8em; /* スマホ時に少し小さく調整 */
    }
}