@charset "UTF-8";

        body {
            font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
            background-color: #f4f6f8;
            color: #333;
            line-height: 1.8;
            margin: 0;
            padding: 20px;
            display: flex;
            justify-content: center;
        }
        .container {
            background-color: #fff;
            width: 100%;
            max-width: 800px;
            padding: 40px;
            border-radius: 10px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
        }
        h1 {
            font-size: 1.8rem;
            color: #2c3e50;
            border-bottom: 2px solid #3498db;
            padding-bottom: 15px;
            margin-bottom: 30px;
        }
        h2 {
            font-size: 1.3rem;
            color: #34495e;
            margin-top: 40px;
            margin-bottom: 15px;
            border-left: 5px solid #3498db;
            padding-left: 15px;
        }
        p {
            margin-bottom: 15px;
            font-size: 0.95rem;
        }
        ul {
            margin-bottom: 20px;
            padding-left: 20px;
        }
        li {
            margin-bottom: 5px;
        }
        .back-btn {
            display: inline-block;
            margin-top: 40px;
            text-decoration: none;
            color: #fff;
            background-color: #3498db;
            padding: 10px 20px;
            border-radius: 5px;
            font-weight: bold;
            transition: background 0.3s;
        }
        .back-btn:hover {
            background-color: #2980b9;
        }
        
        /* スマホ対応 */
        @media (max-width: 600px) {
            .container { padding: 20px; }
            h1 { font-size: 1.5rem; }
        }