* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    line-height: 1.8;
    color: #333;
    background-color: #f5f5f5;
}

nav {
    background-color: #2c3e50;
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.nav-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
}

.site-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

.nav-menu {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    font-size: 1rem;
}

.nav-menu a:hover {
    color: #3498db;
}

main {
    max-width: 1000px;
    margin: 2rem auto;
    padding: 0 2rem;
}

.container {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

h2 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.8rem;
    border-bottom: 3px solid #3498db;
    padding-bottom: 0.5rem;
}

h3 {
    color: #2c3e50;
    margin: 2rem 0 1rem 0;
    font-size: 1.4rem;
}

.welcome p {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.content-list ul {
    list-style: none;
    margin-top: 1rem;
}

.content-list li {
    margin-bottom: 0.8rem;
    padding: 0.8rem;
    background: #f8f9fa;
    border-left: 4px solid #3498db;
    transition: background 0.3s;
}

.content-list li:hover {
    background: #e9ecef;
}

.content-list a {
    color: #2c3e50;
    text-decoration: none;
    font-size: 1.1rem;
}

.post-content {
    margin-top: 2rem;
}

.post-date {
    color: #7f8c8d;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.post-content p {
    margin-bottom: 1.5rem;
    text-align: justify;
}

footer {
    text-align: center;
    padding: 2rem;
    color: #7f8c8d;
    margin-top: 3rem;
}

@media (max-width: 768px) {
    .nav-menu {
        flex-direction: column;
        gap: 0.8rem;
    }
    
    .container {
        padding: 1.5rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
}