/* ================================
   Motion - Dynamic Flow Design
   ================================ */

/* ================================
   CSS Reset & Variables
   ================================ */

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

:root {
    /* Primary - Dark Mode */
    --primary-navy: #0A1128;
    --primary-teal: #2C5F8D;
    --bg-dark: #0D1321;
    --bg-darker: #06080F;
    --text-primary: #FFFFFF;
    --text-secondary: #B8C5D6;
    --text-muted: #6B7C8F;

    /* Accent - Neon Colors */
    --accent-electric: #00F5FF;
    --accent-lime: #CCFF00;
    --accent-magenta: #FF00E5;
    --accent-coral: #FF6B35;

    /* Gradients */
    --gradient-neon: linear-gradient(135deg, var(--accent-electric) 0%, var(--accent-magenta) 100%);
    --gradient-cyber: linear-gradient(135deg, var(--accent-lime) 0%, var(--accent-electric) 100%);

    /* Spacing System (8px base) */
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
    --spacing-xl: 48px;
    --spacing-2xl: 64px;
    --spacing-3xl: 96px;

    /* Transitions */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: 0.8s cubic-bezier(0.68, -0.55, 0.265, 1.55);

    /* Shadows */
    --shadow-glow-electric: 0 0 20px rgba(0, 245, 255, 0.5);
    --shadow-glow-lime: 0 0 20px rgba(204, 255, 0, 0.5);
    --shadow-glow-magenta: 0 0 20px rgba(255, 0, 229, 0.5);
    --shadow-dark: 0 10px 40px rgba(0, 0, 0, 0.6);
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
}

h1, h2, h3, h4 {
    font-family: 'Archivo Black', 'Noto Sans JP', sans-serif;
    font-weight: 900;
    line-height: 1.2;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.fullscreen {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: var(--spacing-xl) 0;
}

section:not(.hero) {
    padding: calc(var(--spacing-xl) * 2) 0;
}

/* ================================
   Particle Background
   ================================ */

#particle-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ================================
   Progress Indicator
   ================================ */

.progress-indicator {
    position: fixed;
    top: 50%;
    right: var(--spacing-md);
    transform: translateY(-50%);
    z-index: 100;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.current-section {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-electric);
    text-shadow: var(--shadow-glow-electric);
}

.progress-bar {
    width: 2px;
    height: 100px;
    background: rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.progress-bar::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 0%;
    background: var(--gradient-neon);
    transition: height var(--transition-slow);
}

/* ================================
   Navigation
   ================================ */

.main-nav {
    position: fixed;
    top: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    z-index: 100;
    background: rgba(13, 19, 33, 0.8);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 245, 255, 0.2);
    border-radius: 50px;
    padding: var(--spacing-xs) var(--spacing-md);
}

.nav-links {
    display: flex;
    gap: var(--spacing-md);
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition-base);
    position: relative;
}

.nav-link:hover {
    color: var(--accent-electric);
    text-shadow: var(--shadow-glow-electric);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0%;
    height: 2px;
    background: var(--accent-electric);
    transition: width var(--transition-base);
}

.nav-link:hover::after {
    width: 100%;
}

/* ================================
   Hero Section
   ================================ */

.hero {
    position: relative;
    background: linear-gradient(135deg, rgba(6, 8, 15, 0.85) 0%, rgba(10, 17, 40, 0.85) 100%);
    overflow: hidden;
    z-index: 1;
}

.hero-bg-animation {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 40%;
    opacity: 0.2;
    z-index: 0;
}

.wave-pattern {
    width: 100%;
    height: 100%;
}

.wave-path {
    fill: var(--accent-electric);
    opacity: 0.1;
    animation: wave-animation 8s ease-in-out infinite;
}

@keyframes wave-animation {
    0%, 100% {
        d: path("M0,100 Q300,150 600,100 T1200,100 L1200,400 L0,400 Z");
    }
    50% {
        d: path("M0,150 Q300,50 600,150 T1200,150 L1200,400 L0,400 Z");
    }
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
}

.hero-title {
    font-size: clamp(3rem, 10vw, 8rem);
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    text-shadow:
        0 0 30px rgba(0, 245, 255, 0.8),
        0 0 60px rgba(0, 245, 255, 0.5),
        0 4px 20px rgba(0, 0, 0, 0.9);
    font-weight: 900;
}

.hero-tagline {
    font-size: clamp(1.2rem, 3vw, 2rem);
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-weight: 300;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.8);
}

.hero-subtitle {
    font-size: clamp(0.9rem, 2vw, 1.2rem);
    color: var(--text-secondary);
    letter-spacing: 0.2em;
    text-transform: uppercase;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.7);
}

.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    z-index: 2;
}

.scroll-text {
    font-size: 0.75rem;
    letter-spacing: 0.2em;
    color: var(--accent-electric);
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: var(--accent-electric);
    animation: scroll-line-animation 2s ease-in-out infinite;
}

@keyframes scroll-line-animation {
    0%, 100% {
        transform: scaleY(1);
        opacity: 1;
    }
    50% {
        transform: scaleY(1.5);
        opacity: 0.5;
    }
}

.cursor-glow {
    position: fixed;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--accent-electric) 0%, transparent 70%);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-fast);
    filter: blur(40px);
    z-index: 1;
}

/* ================================
   About Section (Split Screen)
   ================================ */

.about {
    position: relative;
    background: rgba(13, 19, 33, 0.85);
    z-index: 1;
}

.split-screen {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0;
    min-height: 100vh;
}

.about .section-title {
    position: absolute;
    top: var(--spacing-3xl);
    left: 50%;
    transform: translateX(-50%);
    width: max-content;
    z-index: 10;
}

.about .scrollable-content {
    padding-top: calc(var(--spacing-3xl) * 2.5);
}

.fixed-image {
    position: sticky;
    top: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
}

.image-wrapper {
    position: relative;
    width: 40%;
    max-width: 280px;
}

.profile-img {
    width: 100%;
    height: auto;
    border-radius: 20px;
    border: 2px solid var(--accent-electric);
    box-shadow: var(--shadow-glow-electric), var(--shadow-dark);
}

.image-glow {
    position: absolute;
    top: -20px;
    left: -20px;
    right: -20px;
    bottom: -20px;
    background: var(--gradient-neon);
    border-radius: 20px;
    opacity: 0.2;
    filter: blur(30px);
    z-index: -1;
}

.scrollable-content {
    padding: var(--spacing-3xl) var(--spacing-xl);
    overflow-y: auto;
}

.content-inner {
    max-width: 600px;
}

.section-title {
    font-size: clamp(2rem, 5vw, 4rem);
    margin-bottom: var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    color: var(--text-primary);
    font-weight: 900;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.8);
}

.title-number {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.5rem;
    color: var(--accent-electric);
    opacity: 0.5;
}

.profile-header {
    margin-bottom: var(--spacing-xl);
}

.profile-name {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
    font-weight: 700;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.7);
}

.profile-name-en {
    font-size: 1.2rem;
    color: var(--text-muted);
    font-weight: 300;
    letter-spacing: 0.1em;
}

.info-cards {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.info-card {
    background: rgba(44, 95, 141, 0.1);
    border: 1px solid rgba(0, 245, 255, 0.2);
    border-radius: 16px;
    padding: var(--spacing-lg);
    position: relative;
    overflow: hidden;
    transition: var(--transition-base);
    transform-style: preserve-3d;
}

.info-card:hover {
    border-color: var(--accent-electric);
    box-shadow: var(--shadow-glow-electric);
}

.card-glow {
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, var(--accent-electric) 0%, transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-base);
    pointer-events: none;
}

.info-card:hover .card-glow {
    opacity: 0.1;
}

.card-title {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--accent-lime);
    font-weight: 700;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.7);
}

.card-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.card-list li {
    padding-left: var(--spacing-md);
    position: relative;
    color: var(--text-secondary);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.6);
}

.card-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent-electric);
}

.card-text {
    color: var(--text-secondary);
    line-height: 1.8;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.6);
}

.neon-link {
    color: var(--accent-electric);
    text-decoration: none;
    border-bottom: 1px solid var(--accent-electric);
    transition: var(--transition-base);
}

.neon-link:hover {
    text-shadow: var(--shadow-glow-electric);
    border-bottom-color: transparent;
}

/* ================================
   Story Section (Horizontal Timeline)
   ================================ */

.story {
    position: relative;
    background: rgba(10, 17, 40, 0.85);
    overflow: hidden;
    z-index: 1;
}

.story-container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-3xl) var(--spacing-lg);
}

.timeline-wrapper {
    position: relative;
    padding-left: var(--spacing-xl);
}

.timeline-wrapper::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, transparent 0%, var(--accent-electric) 10%, var(--accent-electric) 90%, transparent 100%);
}

.timeline-track {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3xl);
}

.timeline-item {
    position: relative;
    padding-left: var(--spacing-lg);
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -22px;
    top: 8px;
    width: 12px;
    height: 12px;
    background: var(--accent-lime);
    border-radius: 50%;
    box-shadow: 0 0 20px var(--accent-lime);
}

.timeline-year {
    font-family: 'JetBrains Mono', monospace;
    font-size: 3rem;
    font-weight: 700;
    color: var(--accent-lime);
    text-shadow: var(--shadow-glow-lime);
    margin-bottom: var(--spacing-md);
}

.timeline-content h3 {
    font-size: 1.8rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.timeline-content p {
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ================================
   Lesson Section (3D Cards)
   ================================ */

.lesson {
    position: relative;
    background: rgba(13, 19, 33, 0.85);
    z-index: 1;
}

.lesson-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.lesson-card {
    background: rgba(44, 95, 141, 0.1);
    border: 1px solid rgba(0, 245, 255, 0.2);
    border-radius: 16px;
    padding: var(--spacing-xl);
    position: relative;
    overflow: hidden;
    transition: var(--transition-slow);
    cursor: pointer;
    opacity: 1;
}

.lesson-card:hover {
    transform: translateY(-10px);
    border-color: var(--accent-electric);
    box-shadow: var(--shadow-glow-electric), var(--shadow-dark);
}

.card-number {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    font-family: 'JetBrains Mono', monospace;
    font-size: 3rem;
    font-weight: 700;
    color: rgba(0, 245, 255, 0.3);
}

.lesson-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    filter: grayscale(0.3);
}

.note-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-style: italic;
}

/* ================================
   Gallery Section (Masonry)
   ================================ */

.gallery {
    position: relative;
    background: rgba(6, 8, 15, 0.85);
    z-index: 1;
}

.masonry-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.gallery-item {
    position: relative;
    overflow: hidden;
    border-radius: 16px;
    cursor: pointer;
    transition: var(--transition-base);
}

.gallery-item:nth-child(2) {
    grid-row: span 2;
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.gallery-item:hover img {
    transform: scale(1.1);
}

.item-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--accent-electric) 0%, var(--accent-magenta) 100%);
    opacity: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-base);
}

.gallery-item:hover .item-overlay {
    opacity: 0.8;
}

.overlay-text {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

/* ================================
   Contact Section
   ================================ */

.contact {
    position: relative;
    background: linear-gradient(135deg, rgba(10, 17, 40, 0.85) 0%, rgba(6, 8, 15, 0.85) 100%);
    z-index: 1;
}

.contact-intro {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.2rem;
    margin-bottom: var(--spacing-xl);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

.reservation-form-wrapper {
    margin: var(--spacing-xl) auto;
    max-width: 900px;
}

.custom-reservation-form {
    position: relative;
    background: rgba(13, 19, 33, 0.8);
    padding: var(--spacing-3xl) var(--spacing-xl);
    border-radius: 24px;
    border: 2px solid rgba(0, 245, 255, 0.3);
    box-shadow:
        0 0 50px rgba(0, 245, 255, 0.2),
        0 10px 40px rgba(0, 0, 0, 0.5),
        inset 0 1px 0 rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(15px);
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group.full-width {
    grid-column: 1 / -1;
}

.form-label {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}

.required {
    color: var(--accent-coral);
}

.form-input,
.form-textarea {
    background: rgba(6, 8, 15, 0.8);
    border: 2px solid rgba(0, 245, 255, 0.2);
    border-radius: 12px;
    padding: var(--spacing-md);
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition-base);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent-electric);
    box-shadow: 0 0 20px rgba(0, 245, 255, 0.3);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--text-muted);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-note {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: var(--spacing-xs);
    line-height: 1.6;
}

.radio-group {
    display: flex;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-sm);
}

.radio-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
    color: var(--text-secondary);
    transition: var(--transition-base);
}

.radio-label:hover {
    color: var(--text-primary);
}

.radio-label input[type="radio"] {
    display: none;
}

.radio-custom {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(0, 245, 255, 0.4);
    border-radius: 50%;
    position: relative;
    transition: var(--transition-base);
}

.radio-label input[type="radio"]:checked + .radio-custom {
    border-color: var(--accent-electric);
    box-shadow: 0 0 15px rgba(0, 245, 255, 0.5);
}

.radio-label input[type="radio"]:checked + .radio-custom::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 10px;
    height: 10px;
    background: var(--accent-electric);
    border-radius: 50%;
}

.form-submit {
    width: 100%;
    margin-top: var(--spacing-xl);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.1rem;
    font-weight: 700;
    justify-content: center;
}

.contact-divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: calc(var(--spacing-xl) * 1.5) auto;
    max-width: 600px;
}

.contact-divider::before,
.contact-divider::after {
    content: '';
    flex: 1;
    border-bottom: 2px solid rgba(0, 245, 255, 0.2);
}

.contact-divider span {
    padding: 0 var(--spacing-lg);
    color: var(--accent-electric);
    font-size: 1rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.contact-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
    flex-wrap: wrap;
}

.btn-neon {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    background: rgba(0, 245, 255, 0.1);
    border: 2px solid var(--accent-electric);
    border-radius: 50px;
    color: var(--accent-electric);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    position: relative;
    overflow: hidden;
    transition: var(--transition-base);
}

.btn-neon:hover {
    background: var(--accent-electric);
    color: var(--bg-dark);
    box-shadow: var(--shadow-glow-electric);
    transform: translateY(-2px);
}

.btn-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-neon:hover .btn-glow {
    width: 300px;
    height: 300px;
}

/* ================================
   Footer
   ================================ */

.footer {
    background: rgba(6, 8, 15, 0.85);
    padding: var(--spacing-xl);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    position: relative;
    z-index: 1;
}

/* ================================
   Lightbox Modal
   ================================ */

.lightbox {
    display: none;
    position: fixed;
    z-index: 9999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.95);
    animation: fadeIn 0.3s ease;
}

.lightbox-close {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    color: var(--accent-electric);
    font-size: 3rem;
    font-weight: 300;
    cursor: pointer;
    transition: var(--transition-base);
    z-index: 10000;
}

.lightbox-close:hover {
    text-shadow: var(--shadow-glow-electric);
    transform: rotate(90deg);
}

.lightbox-content {
    margin: auto;
    display: block;
    max-width: 90%;
    max-height: 85vh;
    object-fit: contain;
    animation: zoomIn 0.3s ease;
}

@keyframes zoomIn {
    from {
        transform: scale(0.7);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.lightbox-caption {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    text-align: center;
    color: var(--text-secondary);
    padding: var(--spacing-md) 0;
    font-size: 1rem;
}

/* ================================
   Responsive - Tablet & Mobile
   ================================ */

@media (max-width: 1024px) {
    .container {
        max-width: 900px;
        padding: 0 var(--spacing-md);
    }

    .lesson-cards {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    }

    .masonry-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }

    .hero-title {
        font-size: 3.5rem;
    }

    .section-title {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-md);
    }

    section:not(.hero) {
        padding: var(--spacing-xl) 0;
    }

    .split-screen {
        grid-template-columns: 1fr;
    }

    .fixed-image {
        position: relative;
        height: 50vh;
        margin-bottom: var(--spacing-lg);
    }

    .image-wrapper {
        width: 60%;
        max-width: 250px;
    }

    .scrollable-content {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .timeline-item {
        /* 固定幅を削除し、流動的に */
        min-width: auto;
        max-width: 100%;
        width: 100%;
    }

    .timeline-year {
        font-size: 2.5rem; /* 3rem → 2.5rem */
    }

    .lesson-cards {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .masonry-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .gallery-item:nth-child(2) {
        grid-row: span 1;
    }

    .progress-indicator {
        display: none;
    }

    .main-nav {
        width: 90%;
    }

    .nav-links {
        gap: var(--spacing-sm);
    }

    .nav-link {
        font-size: 0.75rem;
    }

    .hero-title {
        font-size: 3rem;
    }

    .section-title {
        font-size: 2.25rem;
    }

    .form-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .radio-group {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .custom-reservation-form {
        padding: var(--spacing-xl) var(--spacing-md);
    }
}

/* ================================
   600px - Medium Mobile Devices
   ================================ */

@media (max-width: 600px) {
    /* Navigation */
    .main-nav {
        width: 95%;
        padding: var(--spacing-xs) var(--spacing-sm);
    }

    .nav-links {
        gap: var(--spacing-xs); /* 8px */
    }

    .nav-link {
        font-size: 0.8rem; /* 0.9rem → 0.8rem */
    }

    /* Section Titles */
    .section-title {
        font-size: 2.15rem; /* 2.25rem → 2.15rem */
    }

    /* Story Container */
    .story-container {
        padding: var(--spacing-xl) var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .profile-name {
        font-size: 2rem; /* 2.5rem → 2rem */
    }

    .profile-name-en {
        font-size: 1rem; /* 1.2rem → 1rem */
    }

    .timeline-item {
        /* 固定幅を削除 */
        min-width: auto;
        max-width: 100%;
        width: 100%;
        padding-left: var(--spacing-md); /* 24px */
    }

    .timeline-year {
        font-size: 2rem; /* 2.5rem → 2rem */
    }

    .image-wrapper {
        width: 70%;
        max-width: 200px;
    }

    .form-label {
        font-size: 0.9rem;
    }

    .form-input,
    .form-textarea {
        padding: var(--spacing-sm); /* 24px → 16px */
        font-size: 0.95rem;
    }

    .form-submit {
        padding: var(--spacing-sm) var(--spacing-lg);
        font-size: 1rem;
    }

    .lesson-cards {
        gap: var(--spacing-sm);
    }

    .masonry-grid {
        gap: var(--spacing-sm);
    }

    .nav-link {
        font-size: 0.7rem;
        padding: var(--spacing-xs);
    }
}

/* ================================
   320px - Small Mobile Devices
   ================================ */

@media (max-width: 320px) {
    /* Container & Layout */
    .container {
        padding: 0 var(--spacing-xs); /* 8px */
    }

    section:not(.hero) {
        padding: var(--spacing-lg) 0; /* 32px vertical */
    }

    /* Typography */
    .hero-title {
        font-size: 2rem; /* 2.5rem → 2rem */
    }

    .section-title {
        font-size: 1.75rem; /* 2rem → 1.75rem */
    }

    .profile-name {
        font-size: 1.75rem; /* 2rem → 1.75rem */
    }

    /* Navigation */
    .nav-link {
        font-size: 0.65rem; /* 0.7rem → 0.65rem */
        padding: 4px 6px;
    }

    /* Timeline */
    .timeline-item {
        padding-left: var(--spacing-sm); /* 16px */
    }

    .timeline-year {
        font-size: 1.75rem; /* 2rem → 1.75rem */
        margin-bottom: var(--spacing-sm);
    }

    .timeline-content h3 {
        font-size: 1.4rem; /* 1.8rem → 1.4rem */
    }

    /* Form */
    .custom-reservation-form {
        padding: var(--spacing-lg) var(--spacing-sm); /* 32px 16px */
    }

    .form-input,
    .form-textarea {
        padding: 12px; /* 16px → 12px */
        font-size: 0.9rem;
    }

    .form-note {
        font-size: 0.8rem;
    }

    /* Cards */
    .lesson-card {
        padding: var(--spacing-md); /* 24px */
    }

    .card-number {
        font-size: 2rem; /* 3rem → 2rem */
    }

    /* Images */
    .image-wrapper {
        width: 80%; /* 70% → 80% */
        max-width: 180px; /* 200px → 180px */
    }
}

/* ================================
   Accessibility
   ================================ */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus styles for keyboard navigation */
a:focus,
button:focus,
[data-tilt]:focus,
[data-lightbox]:focus {
    outline: 2px solid var(--accent-electric);
    outline-offset: 4px;
}