body {
    font-family: 'Noto Sans JP', sans-serif;
    line-height: 1.8;
    margin: 0;
    padding: 0;
    background-color: #121212; /* 暗い背景色 */
    color: #e0e0e0; /* 明るいテキスト色 */
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    background: #1e1e1e; /* コンテンツエリアの背景色 */
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
    padding: 40px;
    max-width: 800px;
    width: 90%;
    text-align: center;
    border: 1px solid #333;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    color: #ffffff;
}

.subtitle {
    font-size: 1.2em;
    font-weight: bold;
    color: #bbbbbb;
    margin-bottom: 20px;
}

.description {
    font-size: 1em;
    margin-bottom: 30px;
}

main h2 {
    border-bottom: 2px solid #333;
    padding-bottom: 10px;
    margin-bottom: 20px;
    font-size: 1.8em;
    color: #ffffff;
}

.links {
    list-style: none;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
}

.links li a {
    display: block;
    padding: 12px 25px;
    background-color: #007bff;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    transition: background-color 0.3s, transform 0.3s;
}

.links li a:hover {
    background-color: #0056b3;
    transform: translateY(-2px);
}

footer {
    margin-top: 40px;
    font-size: 0.9em;
    color: #777;
}