/* CSS Variables - Monochrome Palette */
        :root {
            --color-black: #0a0a0a;
            --color-white: #ffffff;
            --color-gray-100: #f5f5f5;
            --color-gray-200: #e5e5e5;
            --color-gray-300: #d4d4d4;
            --color-gray-600: #525252;
            --color-gray-800: #262626;

            --font-mincho: 'Shippori Mincho', serif;
            --font-gothic: 'Noto Sans JP', sans-serif;

            --spacing-xs: 0.5rem;
            --spacing-sm: 1rem;
            --spacing-md: 2rem;
            --spacing-lg: 4rem;
            --spacing-xl: 8rem;

            --border-thin: 1px solid var(--color-gray-200);
            --border-thick: 2px solid var(--color-black);

            --transition-fast: 0.2s ease-in-out;
            --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
        }

        /* Reset & Base Styles */
        * { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; font-size: 16px; }
        body {
            font-family: var(--font-gothic);
            color: var(--color-black);
            background-color: var(--color-white);
            line-height: 1.8;
            letter-spacing: 0.05em;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        /* Typography */
        h1, h2, h3, h4, .mincho { font-family: var(--font-mincho); }
        h1 { font-size: clamp(2rem, 4vw, 3.5rem); font-weight: 800; line-height: 1.3; margin-bottom: var(--spacing-sm); letter-spacing: 0.1em; }
        h2 { font-size: clamp(1.5rem, 3vw, 2.5rem); font-weight: 700; line-height: 1.4; margin-bottom: var(--spacing-md); letter-spacing: 0.08em; text-align: center; }
        h3 { font-size: clamp(1.25rem, 2vw, 1.5rem); font-weight: 600; line-height: 1.5; margin-bottom: var(--spacing-sm); }
        p { font-size: 1rem; font-weight: 400; margin-bottom: var(--spacing-sm); color: var(--color-gray-800); }
        .text-sm { font-size: 0.875rem; color: var(--color-gray-600); }
        .text-center { text-align: center; }

        /* Layout & Utilities */
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 5%;
        }
        .section { padding: var(--spacing-xl) 0; }
        .bg-light { background-color: var(--color-gray-100); }
        .bg-dark { background-color: var(--color-black); color: var(--color-white); }
        .bg-dark p { color: var(--color-gray-300); }
        [hidden] { display: none !important; }
        body.modal-open { overflow: hidden; }
        .grid { display: grid; gap: var(--spacing-md); }
        .flex { display: flex; align-items: center; justify-content: center; }

        /* Buttons (CTA) */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 1rem 2.5rem;
            font-family: var(--font-gothic);
            font-weight: 700;
            font-size: 1rem;
            text-decoration: none;
            cursor: pointer;
            transition: var(--transition-smooth);
            border-radius: 0; /* Sharp edges for minimalism */
            letter-spacing: 0.05em;
        }
        .btn-primary {
            background-color: var(--color-black);
            color: var(--color-white);
            border: 1px solid var(--color-black);
        }
        .btn-primary:hover {
            background-color: var(--color-white);
            color: var(--color-black);
        }
        .btn-outline {
            background-color: transparent;
            color: var(--color-black);
            border: 1px solid var(--color-black);
        }
        .btn-outline:hover {
            background-color: var(--color-black);
            color: var(--color-white);
        }
        .btn-outline-white {
            background-color: transparent;
            color: var(--color-white);
            border: 1px solid var(--color-white);
        }
        .btn-outline-white:hover {
            background-color: var(--color-white);
            color: var(--color-black);
        }

        /* --- Header --- */
        header {
            position: fixed;
            top: 0; left: 0; right: 0;
            background-color: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(8px);
            border-bottom: var(--border-thin);
            z-index: 1000;
            transition: var(--transition-fast);
        }
        .header-inner {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 80px;
            max-width: 1400px;
            margin: 0 auto;
            padding: 0 5%;
        }
        .logo {
            font-family: var(--font-mincho);
            font-size: 1.5rem;
            font-weight: 800;
            letter-spacing: 0.15em;
            text-decoration: none;
            color: var(--color-black);
        }
        .nav-links { display: flex; gap: var(--spacing-md); list-style: none; }
        .nav-links a {
            font-family: var(--font-gothic);
            font-size: 0.9rem;
            font-weight: 500;
            text-decoration: none;
            color: var(--color-gray-800);
            transition: color var(--transition-fast);
        }
        .nav-links a:hover { color: var(--color-black); }
        .header-cta { display: flex; gap: var(--spacing-sm); }
        .header-cta .btn { padding: 0.6rem 1.2rem; font-size: 0.85rem; }

        /* --- Main Content --- */
        main { padding-top: 80px; }

        /* Footer */
        footer {
            background-color: var(--color-black);
            color: var(--color-gray-300);
            padding: var(--spacing-lg) 0 var(--spacing-md);
            text-align: center;
        }
        .footer-logo {
            font-family: var(--font-mincho);
            color: var(--color-white);
            font-size: 1.5rem;
            font-weight: 800;
            letter-spacing: 0.15em;
            margin-bottom: var(--spacing-md);
        }
        .footer-links {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: var(--spacing-sm) var(--spacing-md);
            margin-bottom: var(--spacing-md);
            list-style: none;
        }
        .footer-links a { color: var(--color-gray-300); text-decoration: none; font-size: 0.9rem; transition: color var(--transition-fast); }
        .footer-links a:hover { color: var(--color-white); }
        .copyright { font-size: 0.8rem; color: var(--color-gray-600); }