/* ===================================
   CSS Variables & Reset - Modern Design
   =================================== */
:root {
    /* Modern Color Palette */
    --primary: #0f766e;
    --primary-light: #14b8a6;
    --primary-dark: #0d4e47;
    --accent: #f59e0b;
    --accent-light: #fbbf24;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --border: #e2e8f0;
    
    /* Modern Shadows */
    --shadow-xs: 0 1px 2px 0 rgba(15, 118, 110, 0.05);
    --shadow-sm: 0 2px 8px 0 rgba(15, 118, 110, 0.08);
    --shadow-md: 0 4px 16px 0 rgba(15, 118, 110, 0.1);
    --shadow-lg: 0 8px 32px 0 rgba(15, 118, 110, 0.12);
    --shadow-xl: 0 16px 48px 0 rgba(15, 118, 110, 0.14);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 3rem;
    --spacing-xl: 5rem;
    
    /* Typography */
    --font-sans: 'Inter', 'Zen Maru Gothic', sans-serif;
    --font-display: 'Outfit', 'Zen Maru Gothic', sans-serif;
    
    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
    font-family: var(--font-sans);
    color: var(--text-primary);
    line-height: 1.7;
    background-color: var(--bg-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===================================
   Container
   =================================== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 6rem 0;
}

/* ===================================
   Navigation - Minimal Modern
   =================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-sm);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    text-decoration: none;
    transition: var(--transition);
}

.logo:hover {
    opacity: 0.8;
}

.logo-image {
    height: 50px;
    width: auto;
    border-radius: 8px;
}

.logo-main {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    font-family: var(--font-display);
    letter-spacing: -0.02em;
}

.nav-menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    padding: 0.5rem 0;
    position: relative;
    transition: var(--transition);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    transform: translateX(-50%);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
}

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

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.hamburger span {
    width: 24px;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    border-radius: 2px;
}

/* ===================================
   Hero - Bold & Modern
   =================================== */
.hero {
    height: 100vh;
    min-height: 700px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #0d4e47 0%, #0f766e 50%, #14b8a6 100%);
    overflow: hidden;
}

.hero-particles {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 20% 30%, rgba(20, 184, 166, 0.15), transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(245, 158, 11, 0.1), transparent 50%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(-20px, -20px); }
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.1);
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: white;
    max-width: 900px;
    padding: 2rem;
}

.hero-title {
    font-size: 4.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.1;
    font-family: var(--font-display);
    letter-spacing: -0.03em;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    font-weight: 400;
    line-height: 1.8;
    letter-spacing: 0.01em;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 1rem 2rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--font-sans);
}

.btn-primary {
    background: var(--accent);
    color: white;
    box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
    background: var(--accent-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.15);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.25);
    border-color: rgba(255, 255, 255, 0.5);
}

.btn-large {
    padding: 1.25rem 2.5rem;
    font-size: 1.1rem;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    color: white;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    animation: bounce 2s infinite;
    cursor: pointer;
}

.scroll-indicator span {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(-10px); }
}

.fade-in {
    animation: fadeIn 1s ease forwards;
    opacity: 0;
}

.delay-1 { animation-delay: 0.2s; }
.delay-2 { animation-delay: 0.4s; }

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
    from {
        opacity: 0;
        transform: translateY(20px);
    }
}

/* ===================================
   Sections - Clean Layout
   =================================== */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-label {
    display: inline-block;
    color: var(--primary);
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 0.75rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-family: var(--font-display);
    letter-spacing: -0.02em;
}

.title-decoration {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    margin: 1rem auto 0;
    border-radius: 2px;
}

/* ===================================
   About Section - Minimal
   =================================== */
.about-section {
    background: var(--bg-secondary);
}

.about-content-simple {
    max-width: 800px;
    margin: 0 auto;
}

.about-text {
    font-size: 1.125rem;
    line-height: 2;
    color: var(--text-secondary);
    text-align: center;
}

/* ===================================
   Research Cards - Modern Grid
   =================================== */
.bg-gradient {
    background: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.research-card {
    background: white;
    padding: 2.5rem 2rem;
    border-radius: 16px;
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
}

.research-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.research-number {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    font-size: 3rem;
    font-weight: 900;
    color: var(--bg-tertiary);
    font-family: var(--font-display);
    line-height: 1;
}

.research-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 1rem;
    font-family: var(--font-display);
}

.research-desc {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===================================
   Conservation - Accent Cards
   =================================== */
.conservation-section {
    background: var(--bg-secondary);
}

.conservation-main-card {
    background: white;
    padding: 3rem;
    border-radius: 20px;
    border: 1px solid var(--border);
    margin-bottom: 2rem;
}

.conservation-header-box {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--bg-tertiary);
}

.conservation-icon-circle {
    width: 64px;
    height: 64px;
    background: var(--primary);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    flex-shrink: 0;
}

.conservation-title {
    font-size: 1.75rem;
    color: var(--text-primary);
    font-weight: 700;
    font-family: var(--font-display);
}

.conservation-tagline {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-top: 0.25rem;
}

.conservation-intro {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: var(--bg-secondary);
    border-radius: 12px;
    border-left: 4px solid var(--accent);
}

.pillars-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.pillar-box {
    background: var(--primary);
    padding: 2rem 1.5rem;
    border-radius: 16px;
    text-align: center;
    color: white;
    transition: var(--transition);
}

.pillar-box:hover {
    transform: translateY(-4px);
    background: var(--primary-light);
}

.pillar-icon-circle {
    width: 56px;
    height: 56px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin: 0 auto 1rem;
}

.pillar-box h4 {
    font-size: 1.25rem;
    font-weight: 700;
    font-family: var(--font-display);
}

.conservation-secondary-card {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid var(--border);
    text-align: center;
    transition: var(--transition);
}

.conservation-secondary-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.conservation-text {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===================================
   Map Section
   =================================== */
.map-section {
    background: linear-gradient(180deg, var(--bg-primary), var(--bg-secondary));
}

.map-card {
    background: white;
    padding: 4rem 3rem;
    border-radius: 24px;
    border: 1px solid var(--border);
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
    position: relative;
}

.map-icon-large {
    width: 96px;
    height: 96px;
    background: var(--primary);
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    margin-bottom: 2rem;
    position: relative;
    z-index: 1;
}

.map-card h3 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    font-family: var(--font-display);
    font-weight: 700;
    position: relative;
    z-index: 1;
}

.map-description {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    position: relative;
    z-index: 1;
}

.map-card .btn {
    position: relative;
    z-index: 1;
}

/* ===================================
   SNS Section
   =================================== */
.sns-section {
    background: var(--bg-secondary);
}

.sns-description {
    text-align: center;
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

.social-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.social-card {
    background: white;
    padding: 2.5rem 2rem;
    border-radius: 16px;
    border: 1px solid var(--border);
    text-align: center;
    transition: var(--transition);
    display: block;
}

.social-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.social-card.twitter { border-top: 3px solid #1DA1F2; }
.social-card.youtube { border-top: 3px solid #FF0000; }
.social-card.instagram { border-top: 3px solid #E1306C; }

.social-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin: 0 auto 1.5rem;
    color: white;
}

.social-card.twitter .social-icon { background: #1DA1F2; }
.social-card.youtube .social-icon { background: #FF0000; }
.social-card.instagram .social-icon { background: linear-gradient(45deg, #f09433, #e6683c, #dc2743, #cc2366, #bc1888); }

.social-card h3 {
    font-size: 1.25rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-weight: 700;
    font-family: var(--font-display);
}

.social-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: var(--primary-dark);
    color: white;
    padding: 3rem 0 2rem;
}

.footer-main {
    text-align: center;
    margin-bottom: 2rem;
}

.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.footer-logo-image {
    height: 50px;
    border-radius: 8px;
}

.footer-logo h4 {
    font-size: 1.25rem;
    font-weight: 700;
    font-family: var(--font-display);
}

.footer-logo p {
    font-size: 0.875rem;
    opacity: 0.8;
}

.footer-tagline {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    color: var(--accent-light);
    font-size: 1rem;
    margin-bottom: 2rem;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    font-weight: 500;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--accent-light);
}

.footer-bottom {
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
}

/* ===================================
   Responsive
   =================================== */
@media (max-width: 968px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: white;
        flex-direction: column;
        justify-content: flex-start;
        padding: 2rem;
        gap: 1.5rem;
        transition: left 0.3s;
        box-shadow: var(--shadow-lg);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hamburger {
        display: flex;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .research-grid,
    .pillars-container,
    .social-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .section {
        padding: 4rem 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
}

/* ===================================
   Back to Top
   =================================== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    border: none;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    z-index: 999;
    transition: var(--transition);
    box-shadow: var(--shadow-lg);
}

.back-to-top:hover {
    background: var(--primary-light);
    transform: translateY(-4px);
}