body {
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    line-height: 1.8;
    margin: 0;
    padding: 0;
    background: #f9f9f9;
    color: #333;
}

.container {
    max-width: 800px;
    margin: auto;
    overflow: hidden;
    padding: 20px;
}

header {
    padding: 40px 0;
    border-bottom: 1px solid #eee;
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    margin: 0;
    animation: fadeInDown 1s;
}

main {
    padding: 20px 0;
    animation: fadeInUp 1s;
}

article {
    background: #fff;
    padding: 30px;
    border-radius: 5px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

footer {
    text-align: center;
    padding: 40px 20px;
    margin-top: 40px;
    border-top: 1px solid #eee;
    color: #777;
}

a {
    color: #007bff;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.back-link {
    display: inline-block;
    margin-top: 30px;
    padding: 10px 20px;
    background: #333;
    color: #fff;
    border-radius: 5px;
    transition: background 0.3s;
}

.back-link:hover {
    background: #555;
}

/* Animations */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}