/* ========================================
   CSS Variables & Design System
   ======================================== */
:root {
    /* Color Palette - Traditional Japanese Aesthetics */
    --color-kinari: #F5F1E8;
    /* 生成り - Natural beige */
    --color-sumi: #2C2C2C;
    /* 墨色 - Ink black */
    --color-tsuchikabe: #A89F91;
    /* 土壁 - Earth wall gray */
    --color-shikkui: #E8E3D8;
    /* 漆喰 - Plaster white */
    --color-shu: #C73E3A;
    /* 朱色 - Vermillion */
    --color-kon: #223A5E;
    /* 紺色 - Deep indigo */
    --color-moegi: #7BA23F;
    /* 萌葱色 - Onion green */
    --color-suoh: #8C4841;
    /* 蘇芳 - Sappanwood */

    /* Functional Colors */
    --color-bg-primary: var(--color-kinari);
    --color-bg-secondary: var(--color-shikkui);
    --color-text-primary: var(--color-sumi);
    --color-text-secondary: var(--color-tsuchikabe);
    --color-accent: var(--color-shu);
    --color-accent-dark: var(--color-suoh);

    /* Typography */
    --font-ja: 'Noto Serif JP', serif;
    --font-en: 'Cormorant Garamond', serif;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    --spacing-xxl: 8rem;

    /* Layout */
    --container-max: 1200px;
    --header-height: 80px;

    /* Transitions */
    --transition-smooth: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.3s ease;
}

/* ========================================
   Reset & Base Styles
   ======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-ja);
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

/* Washi Paper Texture Overlay */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('images/washi_texture.png');
    background-size: 400px;
    opacity: 0.03;
    pointer-events: none;
    z-index: 1;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-fast);
}

ul {
    list-style: none;
}

/* ========================================
   Container
   ======================================== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   Header & Navigation
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background: rgba(245, 241, 232, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(168, 159, 145, 0.2);
    z-index: 1000;
    transition: var(--transition-smooth);
}

.nav {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    position: relative;
    cursor: pointer;
    transition: var(--transition-fast);
}

.nav-brand:hover {
    opacity: 0.7;
}

.brand-ja {
    font-size: 1.25rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    margin-bottom: 0.25rem;
}

.brand-en {
    font-family: var(--font-en);
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    letter-spacing: 0.15em;
    text-transform: uppercase;
}

.nav-menu {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-menu a {
    font-family: var(--font-en);
    font-size: 0.95rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-accent);
    transition: width 0.4s ease;
}

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

/* Language Toggle */
.lang-toggle {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.lang-btn {
    font-family: var(--font-ja);
    font-size: 0.85rem;
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid var(--color-tsuchikabe);
    color: var(--color-text-primary);
    cursor: pointer;
    transition: var(--transition-fast);
    border-radius: 2px;
    letter-spacing: 0.05em;
}

.lang-btn:hover {
    background: var(--color-shikkui);
    border-color: var(--color-sumi);
}

.lang-btn.active {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: white;
}

/* Hide/Show elements based on language */
[data-lang] {
    transition: opacity 0.3s ease;
}


/* ========================================
   Hero Section
   ======================================== */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-visual {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.hero-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.6;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom,
            rgba(245, 241, 232, 0.3) 0%,
            rgba(245, 241, 232, 0.7) 100%);
}

.hero-content {
    position: relative;
    z-index: 10;
    text-align: center;
    padding: var(--spacing-md);
    animation: fadeInUp 1.2s ease-out;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 4.5rem);
    font-weight: 400;
    letter-spacing: 0.15em;
    line-height: 1.4;
    margin-bottom: var(--spacing-md);
    color: var(--color-sumi);
}

.hero-subtitle-en {
    font-family: var(--font-en);
    font-size: clamp(1.25rem, 2.5vw, 1.75rem);
    font-weight: 300;
    letter-spacing: 0.1em;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-xs);
}

.hero-subtitle-en-small {
    font-family: var(--font-en);
    font-size: clamp(0.9rem, 1.5vw, 1.1rem);
    font-weight: 300;
    font-style: italic;
    letter-spacing: 0.08em;
    color: var(--color-tsuchikabe);
}

.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    animation: fadeIn 1.5s ease-out 0.5s both;
}

.scroll-indicator span {
    font-family: var(--font-en);
    font-size: 0.75rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-text-secondary);
}

.scroll-line {
    width: 1px;
    height: 60px;
    background: linear-gradient(to bottom,
            var(--color-text-secondary),
            transparent);
    animation: scrollLine 2s ease-in-out infinite;
}

/* ========================================
   Section Styles
   ======================================== */
.section {
    padding: var(--spacing-xxl) 0;
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 400;
    letter-spacing: 0.15em;
    margin-bottom: var(--spacing-sm);
    color: var(--color-sumi);
}

.section-title-en {
    font-family: var(--font-en);
    font-size: clamp(1rem, 2vw, 1.25rem);
    font-weight: 300;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-text-secondary);
}

/* ========================================
   Concept Section
   ======================================== */
.concept-section {
    background: linear-gradient(to bottom,
            var(--color-bg-primary) 0%,
            var(--color-shikkui) 100%);
}

.concept-content {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    max-width: 900px;
    margin: 0 auto;
}

.concept-block {
    position: relative;
    padding-left: var(--spacing-lg);
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition-smooth);
}

.concept-block.visible {
    opacity: 1;
    transform: translateY(0);
}

.concept-number {
    position: absolute;
    left: 0;
    top: 0;
    font-family: var(--font-en);
    font-size: 3rem;
    font-weight: 300;
    color: var(--color-accent);
    opacity: 0.3;
    line-height: 1;
}

.concept-heading {
    font-size: clamp(1.5rem, 3vw, 2rem);
    font-weight: 500;
    letter-spacing: 0.1em;
    margin-bottom: var(--spacing-md);
    color: var(--color-sumi);
}

.concept-text {
    font-size: 1.1rem;
    line-height: 2;
    letter-spacing: 0.05em;
    color: var(--color-text-primary);
}

/* ========================================
   Pillars Section
   ======================================== */
.pillars-section {
    background: var(--color-bg-primary);
}

.pillars-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.pillar-card {
    background: white;
    border-radius: 2px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(44, 44, 44, 0.08);
    transition: var(--transition-smooth);
    opacity: 0;
    transform: translateY(40px);
}

.pillar-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.pillar-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px rgba(44, 44, 44, 0.15);
}

.pillar-image-wrapper {
    width: 100%;
    height: 280px;
    overflow: hidden;
    position: relative;
}

.pillar-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.8s ease;
}

.pillar-card:hover .pillar-image {
    transform: scale(1.05);
}

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

.pillar-title-en {
    font-family: var(--font-en);
    font-size: 1.5rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xs);
}

.pillar-title-ja {
    font-size: 1.25rem;
    font-weight: 400;
    letter-spacing: 0.1em;
    margin-bottom: var(--spacing-md);
    color: var(--color-sumi);
}

.pillar-description {
    font-size: 1rem;
    line-height: 1.9;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

.pillar-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.pillar-list li {
    position: relative;
    padding-left: 1.5rem;
    font-size: 0.95rem;
    letter-spacing: 0.05em;
    color: var(--color-text-secondary);
}

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

/* ========================================
   Profile Section
   ======================================== */
.profile-section {
    background: linear-gradient(to bottom,
            var(--color-shikkui) 0%,
            var(--color-bg-primary) 100%);
}

.profile-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.profile-info {
    background: white;
    padding: var(--spacing-xl);
    border-radius: 2px;
    box-shadow: 0 4px 30px rgba(44, 44, 44, 0.1);
}

.profile-name-ja {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 500;
    letter-spacing: 0.15em;
    margin-bottom: var(--spacing-xs);
    color: var(--color-sumi);
}

.profile-name-en {
    font-family: var(--font-en);
    font-size: clamp(1.25rem, 2.5vw, 1.75rem);
    font-weight: 300;
    letter-spacing: 0.15em;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.profile-credentials {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid rgba(168, 159, 145, 0.2);
}

.profile-credentials p {
    font-size: 1rem;
    letter-spacing: 0.08em;
    color: var(--color-text-secondary);
}

.profile-bio {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    text-align: left;
}

.profile-bio p {
    font-size: 1.1rem;
    line-height: 2;
    letter-spacing: 0.05em;
    color: var(--color-text-primary);
}

.profile-links {
    display: flex;
    justify-content: center;
    margin-top: var(--spacing-lg);
}

.profile-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--color-accent);
    color: white;
    border-radius: 2px;
    font-size: 1rem;
    letter-spacing: 0.08em;
    transition: var(--transition-fast);
}

.profile-link:hover {
    background: var(--color-accent-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(199, 62, 58, 0.3);
}

.link-icon {
    width: 20px;
    height: 20px;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background: var(--color-sumi);
    color: var(--color-kinari);
    padding: var(--spacing-xl) 0 var(--spacing-lg);
}

.footer-content {
    text-align: center;
}

.footer-brand {
    margin-bottom: var(--spacing-md);
}

.footer-title-ja {
    font-size: 1.5rem;
    font-weight: 400;
    letter-spacing: 0.15em;
    margin-bottom: var(--spacing-xs);
}

.footer-title-en {
    font-family: var(--font-en);
    font-size: 0.9rem;
    font-weight: 300;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    opacity: 0.7;
}

.footer-copyright {
    font-size: 0.85rem;
    letter-spacing: 0.05em;
    opacity: 0.6;
    margin-top: var(--spacing-md);
}

/* ========================================
   Animations
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes scrollLine {

    0%,
    100% {
        transform: scaleY(0);
        transform-origin: top;
    }

    50% {
        transform: scaleY(1);
        transform-origin: top;
    }
}

/* ========================================
   Responsive Design
   ======================================== */

/* Tablet and below - hide navigation menu to save space */
@media (max-width: 900px) {
    .nav-menu {
        display: none;
    }

    .lang-toggle {
        gap: 0.4rem;
    }

    .lang-btn {
        font-size: 0.8rem;
        padding: 0.45rem 0.9rem;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 70px;
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
        --spacing-xxl: 5rem;
    }

    .brand-ja {
        font-size: 1.1rem;
        letter-spacing: 0.08em;
    }

    .brand-en {
        font-size: 0.7rem;
        letter-spacing: 0.12em;
    }

    .concept-block {
        padding-left: var(--spacing-md);
    }

    .concept-number {
        font-size: 2rem;
    }

    .pillars-grid {
        grid-template-columns: 1fr;
    }

    .profile-info {
        padding: var(--spacing-lg);
    }

    .profile-bio {
        text-align: center;
    }
}

/* Small mobile screens */
@media (max-width: 480px) {
    :root {
        --header-height: 65px;
    }

    .nav {
        padding: 0 var(--spacing-sm);
        gap: 0.5rem;
    }

    .brand-ja {
        font-size: 0.95rem;
        letter-spacing: 0.06em;
    }

    .brand-en {
        font-size: 0.6rem;
        letter-spacing: 0.1em;
    }

    .lang-toggle {
        gap: 0.3rem;
    }

    .lang-btn {
        font-size: 0.7rem;
        padding: 0.4rem 0.7rem;
        letter-spacing: 0.03em;
    }
}

/* Extra small screens */
@media (max-width: 360px) {
    :root {
        --header-height: 60px;
    }

    .nav {
        padding: 0 0.5rem;
        gap: 0.25rem;
    }

    .brand-ja {
        font-size: 0.85rem;
        letter-spacing: 0.04em;
        margin-bottom: 0.15rem;
    }

    .brand-en {
        font-size: 0.5rem;
        letter-spacing: 0.08em;
    }

    .lang-toggle {
        gap: 0.25rem;
    }

    .lang-btn {
        font-size: 0.65rem;
        padding: 0.35rem 0.6rem;
        letter-spacing: 0.02em;
    }
}

/* ========================================
   Utility Classes
   ======================================== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition-smooth);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}