/* === ROOT VARIABLES === */
:root {
    --primary-color: #00d4ff;
    --secondary-color: #007fff;
    --dark-bg: #0f1419;
    --dark-bg-alt: #1a2332;
    --light-bg: #f8f9ff;
    --text-dark: #333;
    --text-light: #f0f0f0;
    --text-muted: #666;
    --animation-duration: 0.8s;
}

/* === KEYFRAME ANIMATIONS === */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(40px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0% { transform: scale(1); box-shadow: 0 10px 30px rgba(0, 212, 255, 0.4); }
    50% { transform: scale(1.05); box-shadow: 0 15px 40px rgba(0, 212, 255, 0.6); }
    100% { transform: scale(1); box-shadow: 0 10px 30px rgba(0, 212, 255, 0.4); }
}

@keyframes kenBurns {
    from {
        transform: scale(1);
    }
    to {
        transform: scale(1.1);
    }
}

/* === CSS Reset and Base Styles === */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Poppins', 'Noto Sans KR', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: #ffffff;
}
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === Header === */
.header {
    background: linear-gradient(135deg, var(--dark-bg) 0%, var(--dark-bg-alt) 100%);
    color: var(--text-light);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    transition: all 0.4s ease-in-out;
}
.header.scrolled {
    background: rgba(15, 20, 25, 0.85);
    backdrop-filter: blur(12px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}
.nav { display: flex; justify-content: space-between; align-items: center; }
.logo h1 a {
    font-size: 1.5rem;
    font-weight: bold;
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
}
.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a { color: white; text-decoration: none; transition: color 0.3s, transform 0.3s; }
.nav-links a:hover { color: var(--primary-color); transform: translateY(-2px); }

/* === Hero Section === */
.hero {
    background-color: var(--dark-bg);
    color: white;
    padding: 120px 0 80px;
    position: relative;
    overflow: hidden;
    min-height: 100vh;
    display: flex;
    align-items: center;
}
.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    
    /* ▼▼▼ 호스팅 서버에 맞는 절대 경로로 수정 ▼▼▼ */
    background-image: url('/img/bg.png');
    
    background-size: cover;
    background-position: center;
    opacity: 0;
    transition: opacity 1.5s ease-in-out;
    animation: kenBurns 20s infinite alternate ease-in-out;
    z-index: -2;
}
.hero::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0;
    background: linear-gradient(135deg, rgba(15, 20, 25, 0.8) 0%, rgba(26, 35, 50, 0.8) 50%, rgba(42, 52, 65, 0.8) 100%);
    z-index: -1;
}
.hero-content { position: relative; z-index: 2; text-align: center; }
.hero-title, .hero-subtitle, .hero-description, .cta-button {
    opacity: 0;
    animation: fadeInUp 1s forwards;
}
.hero-title { font-size: 3.5rem; font-weight: 300; margin-bottom: 1.5rem; line-height: 1.2; }
.hero-subtitle { font-size: 1.3rem; margin-bottom: 2rem; max-width: 800px; margin-left: auto; margin-right: auto; animation-delay: 0.3s; }
.hero-description { font-size: 1.1rem; max-width: 900px; margin: 0 auto 3rem; animation-delay: 0.6s; }
.cta-button {
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    background-size: 200% 200%;
    color: white; padding: 15px 40px; border: none; border-radius: 50px; font-size: 1.1rem;
    font-weight: 600; cursor: pointer; text-decoration: none; display: inline-block;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    animation-delay: 0.9s;
}
.cta-button:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 212, 255, 0.4);
    animation: pulse 1.5s infinite;
}

/* === General Section Styles === */
.section-title { text-align: center; font-size: 2.5rem; font-weight: 600; margin-bottom: 3rem; color: var(--dark-bg-alt); }
.distinction, .advisory-fellow, .expertise, .stats, .final-cta { padding: 80px 0; }

/* === Distinction Section === */
.distinction { background: linear-gradient(to bottom, var(--light-bg), #ffffff); }
.distinction-content { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.distinction-text { font-size: 1.2rem; line-height: 1.8; color: #555; }
.distinction-visual {
    background: linear-gradient(135deg, #00d4ff20, #007fff20);
    padding: 40px; border-radius: 20px; text-align: center;
}
.visual-elements { display: flex; justify-content: space-around; align-items: center; margin-bottom: 2rem; flex-wrap: wrap; gap: 1rem; }
.element {
    width: 80px; height: 80px; border-radius: 50%; display: flex; align-items: center;
    justify-content: center; color: white; font-weight: bold;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.element:hover { transform: scale(1.1) rotate(5deg); box-shadow: 0 10px 20px rgba(0,0,0,0.1); }
.policy { background: linear-gradient(45deg, #ff6b6b, #ff8e8e); }
.rd { background: linear-gradient(45deg, #4ecdc4, #44b3ac); }
.tech { background: linear-gradient(45deg, #45b7d1, #3498db); }


/* === Experts Section === */
.advisory-fellow {
    background: var(--light-bg);
    padding: 80px 0;
}
.experts-container {
    display: flex;
    gap: 2rem;
    overflow-x: auto;
    padding: 20px 5px;
    scroll-behavior: smooth;
    scroll-snap-type: x mandatory;
}
.expert-card {
    background: white;
    padding: 35px 30px;
    border-radius: 16px;
    border: 1px solid #e8eaf0;
    text-align: left;
    min-width: 340px;
    max-width: 360px;
    flex-shrink: 0;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    scroll-snap-align: start;
}
.expert-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}
.expert-card.main {
    border-color: var(--secondary-color);
}
.expert-card::before {
    display: none;
}
.fellow-badge, .expert-badge {
    background: var(--dark-bg-alt);
    color: white;
    padding: 6px 14px;
    border-radius: 30px;
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 20px;
    display: inline-block;
}
.fellow-badge {
    background: var(--secondary-color);
}
.fellow-name, .expert-name {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
    color: var(--dark-bg-alt);
}
.fellow-credentials {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: 24px;
}
.expert-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 24px 0;
}
.expert-tags span {
    background: #f0f2f5;
    color: #555;
    padding: 5px 12px;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}
.fellow-quote, .expert-quote {
    font-style: normal;
    font-size: 1rem;
    color: #444;
    border-left: 3px solid #e0e6ff;
    padding-left: 20px;
    margin: 24px 0 0;
    text-align: left;
    line-height: 1.7;
}
.expert-quote {
    font-size: 0.95rem;
}
.credentials-detail {
    display: none;
}

/* === Expertise Section === */
.expertise { background: white; }
.expertise-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 3rem; margin-top: 3rem; }
.expertise-card {
    background: linear-gradient(135deg, var(--light-bg), #ffffff);
    padding: 30px; border-radius: 15px; border: 1px solid #e0e6ff;
    transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.expertise-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 127, 255, 0.15);
    border-color: var(--secondary-color);
}
.expertise-icon {
    width: 60px; height: 60px; border-radius: 50%; margin-bottom: 1.5rem; display: flex;
    align-items: center; justify-content: center; font-size: 1.5rem; color: white;
}
.expertise-title { font-size: 1.4rem; font-weight: 600; margin-bottom: 1rem; color: var(--dark-bg-alt); }
.expertise-description { color: var(--text-muted); line-height: 1.6; }

/* === Stats Section === */
.stats {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--dark-bg-alt), #2a3441);
    color: white;
}
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 3rem; text-align: center; }
.stat-item { padding: 20px; }
.stat-number {
    font-size: 3.5rem; font-weight: 700; color: var(--primary-color);
    margin-bottom: 0.5rem; transition: color 0.3s;
}
.stat-item:hover .stat-number {
    color: #fff; text-shadow: 0 0 15px var(--primary-color);
}
.stat-label { font-size: 1.1rem; opacity: 0.9; }

/* === Final CTA Section === */
.final-cta {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white; text-align: center;
}
.final-cta-title { font-size: 2.5rem; font-weight: 600; margin-bottom: 1.5rem; }
.final-cta-text { font-size: 1.2rem; margin-bottom: 3rem; opacity: 0.95; }
.cta-button-white {
    background: white; color: var(--secondary-color); padding: 15px 40px; border: none;
    border-radius: 50px; font-size: 1.1rem; font-weight: 600; cursor: pointer;
    transition: all 0.3s; text-decoration: none; display: inline-block;
}
.cta-button-white:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 10px 30px rgba(255, 255, 255, 0.4);
}

/* === Footer === */
.footer { background: var(--dark-bg); color: white; padding: 40px 0; text-align: center; }
.footer-content { text-align: center; margin-bottom: 2rem; }
.footer-title { color: var(--primary-color); margin-bottom: 1rem; font-size: 1.5rem; }
.footer-contact { margin-top: 1rem; font-size: 0.9rem; opacity: 0.8; }
.footer-tagline { font-size: 0.8rem; margin-top: 0.5rem; opacity: 0.7; }

/* === ANIMATION ON SCROLL === */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition-property: opacity, transform;
    transition-duration: var(--animation-duration);
    transition-timing-function: cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.animate-on-scroll.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* === Responsive Design === */
@media (max-width: 768px) {
    .hero-title { font-size: 2.5rem; }
    .distinction-content { grid-template-columns: 1fr; gap: 2rem; }
    .nav-links { display: none; }
    .visual-elements { flex-direction: column; gap: 1rem; }
    .experts-container { flex-direction: column; overflow-x: visible; align-items: center; }
    .expert-card, .expert-card.main { min-width: 90%; max-width: 90%; }
    .hero { padding: 100px 0 60px; min-height: 80vh; }
}

/* Scrollbar Styles */
.experts-container::-webkit-scrollbar {
    height: 8px;
}
.experts-container::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 10px;
}
.experts-container::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 10px;
}
.experts-container::-webkit-scrollbar-thumb:hover {
    background: #999;
}