* {
            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: linear-gradient(to bottom, #fff5f5 0%, #ffffff 100%);
        }

        header {
            background: #fff;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            padding: 1.5rem 0;
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        #header {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        #logo {
            font-size: 0;
        }

        #logo img {
            height: 60px;
            width: auto;
        }

        .gnavi {
            display: flex;
            list-style: none;
            gap: 2rem;
        }

        .gnavi li a {
            color: #c73e3a;
            text-decoration: none;
            font-weight: 600;
            transition: color 0.3s ease;
            font-size: 0.95rem;
        }

        .gnavi li a:hover {
            color: #e85d54;
        }

        .btn-menu {
            display: none;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 3rem 2rem;
        }

        h1 {
            font-size: 2.5rem;
            color: #c73e3a;
            margin-bottom: 2rem;
            padding-bottom: 1rem;
            border-bottom: 3px solid #c73e3a;
            line-height: 1.4;
        }

        article {
            background: #fff;
            padding: 2.5rem;
            border-radius: 12px;
            box-shadow: 0 4px 20px rgba(199, 62, 58, 0.08);
            margin-bottom: 3rem;
        }

        article h2 {
            font-size: 1.8rem;
            color: #c73e3a;
            margin: 2rem 0 1rem;
            padding-left: 1rem;
            border-left: 4px solid #c73e3a;
        }

        article h3 {
            font-size: 1.4rem;
            color: #e85d54;
            margin: 1.5rem 0 0.8rem;
        }

        article h4 {
            font-size: 1.2rem;
            color: #666;
            margin: 1.2rem 0 0.6rem;
        }

        article p {
            margin-bottom: 1.2rem;
            color: #555;
            font-size: 1rem;
        }

        article ul, article ol {
            margin-left: 2rem;
            margin-bottom: 1.2rem;
        }

        article li {
            margin-bottom: 0.5rem;
            color: #555;
        }

        .transition-section {
            background: linear-gradient(135deg, #fff5f5 0%, #ffe8e8 100%);
            padding: 2.5rem;
            border-radius: 12px;
            margin-bottom: 3rem;
            box-shadow: 0 2px 15px rgba(199, 62, 58, 0.05);
        }

        .transition-section p {
            color: #555;
            font-size: 1rem;
            margin-bottom: 1rem;
        }

        .links-section {
            background: #fff;
            padding: 3rem 2.5rem;
            border-radius: 12px;
            box-shadow: 0 4px 20px rgba(199, 62, 58, 0.08);
            margin-bottom: 3rem;
        }

        .links-section h3 {
            font-size: 1.5rem;
            color: #c73e3a;
            margin: 2rem 0 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 2px solid #ffe8e8;
        }

        .links-section h3:first-child {
            margin-top: 0;
        }

        .links-section ul {
            list-style: none;
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 0.8rem 2rem;
            margin-bottom: 2rem;
        }

        .links-section li {
            position: relative;
            padding-left: 1.2rem;
        }

        .links-section li:before {
            content: "▶";
            position: absolute;
            left: 0;
            color: #c73e3a;
            font-size: 0.7rem;
            top: 0.3rem;
        }

        .links-section a {
            color: #555;
            text-decoration: none;
            transition: color 0.3s ease;
            display: inline-block;
            line-height: 1.6;
        }

        .links-section a:hover {
            color: #c73e3a;
            text-decoration: underline;
        }

        footer {
            background: #c73e3a;
            color: #fff;
            padding: 2rem 0;
            margin-top: 4rem;
        }

        #footer {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
            text-align: center;
        }

        #footer address {
            font-style: normal;
            margin-bottom: 1rem;
            line-height: 1.8;
        }

        #footer .home {
            display: inline-block;
            margin-bottom: 1rem;
        }

        #footer img {
            height: 50px;
            width: auto;
            filter: brightness(0) invert(1);
        }

        #footer small {
            display: block;
            opacity: 0.9;
            font-size: 0.85rem;
        }

        #pagetop_btn {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            z-index: 999;
        }

        #pagetop_btn a {
            display: block;
            width: 50px;
            height: 50px;
            background: #c73e3a;
            border-radius: 50%;
            box-shadow: 0 4px 15px rgba(199, 62, 58, 0.3);
            position: relative;
            transition: all 0.3s ease;
        }

        #pagetop_btn a:hover {
            background: #e85d54;
            transform: translateY(-3px);
        }

        #pagetop_btn a:before {
            content: "▲";
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            color: #fff;
            font-size: 1rem;
        }

        @media (max-width: 768px) {
            .gnavi {
                display: none;
            }

            .btn-menu {
                display: block;
            }

            .menu-trigger {
                display: block;
                width: 30px;
                height: 25px;
                position: relative;
            }

            .menu-trigger span {
                display: block;
                width: 100%;
                height: 3px;
                background: #c73e3a;
                position: absolute;
                left: 0;
                transition: all 0.3s ease;
            }

            .menu-trigger span:nth-child(1) {
                top: 0;
            }

            .menu-trigger span:nth-child(2) {
                top: 11px;
            }

            .menu-trigger span:nth-child(3) {
                bottom: 0;
            }

            h1 {
                font-size: 1.8rem;
            }

            article {
                padding: 1.5rem;
            }

            article h2 {
                font-size: 1.4rem;
            }

            article h3 {
                font-size: 1.2rem;
            }

            .container {
                padding: 2rem 1rem;
            }

            .transition-section {
                padding: 1.5rem;
            }

            .links-section {
                padding: 2rem 1.5rem;
            }

            .links-section ul {
                grid-template-columns: 1fr;
                gap: 0.6rem;
            }

            .links-section h3 {
                font-size: 1.3rem;
            }

            #pagetop_btn {
                bottom: 1rem;
                right: 1rem;
            }

            #pagetop_btn a {
                width: 45px;
                height: 45px;
            }

            #logo img {
                height: 45px;
            }
        }

        @media (max-width: 480px) {
            h1 {
                font-size: 1.5rem;
            }

            article h2 {
                font-size: 1.2rem;
            }

            .container {
                padding: 1.5rem 1rem;
            }
        }