body {
    font-family: 'Segoe UI', 'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
    background: #f6f8fa;
    margin: 0;
    color: #222;
}
header {
    background: linear-gradient(90deg, #6a82fb 0%, #fc5c7d 100%);
    color: #fff;
    padding-bottom: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}
.slideshow-container {
    width: 100%;
    max-width: 700px;
    margin: 0 auto 1rem auto;
    overflow: hidden;
    border-radius: 18px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.12);
    background: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 320px;
}
#slideshow-image {
    width: 100%;
    height: 320px;
    object-fit: cover;
    transition: opacity 0.6s;
}
h1 {
    text-align: center;
    margin: 0.5rem 0 0.2rem 0;
    font-size: 2.5rem;
    letter-spacing: 0.1em;
}
nav ul {
    display: flex;
    justify-content: center;
    gap: 2rem;
    list-style: none;
    padding: 0;
    margin: 0.5rem 0 0 0;
}
nav a {
    color: #fff;
    text-decoration: none;
    font-weight: bold;
    font-size: 1.1rem;
    transition: color 0.2s;
}
nav a:hover {
    color: #ffe082;
}
main {
    max-width: 900px;
    margin: 2rem auto;
    padding: 0 1rem;
}
.card {
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.07);
    padding: 2rem 1.5rem;
    margin-bottom: 2rem;
}
.card h2 {
    margin-top: 0;
    color: #6a82fb;
}
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1.2rem;
    margin-top: 1rem;
}
.gallery-grid img {
    width: 100%;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    object-fit: cover;
    height: 140px;
}
footer {
    text-align: center;
    color: #888;
    padding: 1.5rem 0 1rem 0;
    font-size: 0.95rem;
    background: none;
}

/* --- レスポンシブデザイン --- */
@media (max-width: 600px) {
    header {
        padding-bottom: 1rem;
    }
    .slideshow-container {
        max-width: 100%;
        height: 180px;
        min-height: 120px;
    }
    #slideshow-image {
        height: 180px;
    }
    h1 {
        font-size: 1.4rem;
        margin: 0.7rem 0 0.3rem 0;
    }
    nav ul {
        gap: 1rem;
        flex-direction: column;
        align-items: center;
    }
    nav a {
        font-size: 1rem;
    }
    main {
        padding: 0 0.2rem;
    }
    .card {
        padding: 1.2rem 0.7rem;
    }
    .gallery-grid {
        grid-template-columns: 1fr;
        gap: 0.7rem;
    }
    .gallery-grid img {
        height: 100px;
    }
}