:root {
    --primary-color: #3b2b73;
    --secondary-color: #0d47a1;
    --accent-color: #2196f3;
    --text-dark: #222222;
    --text-light: #555555;
    --bg-light: #f4f6f9;
    --white: #ffffff;
    --border-color: #eaeaea;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
    font-family: 'Noto Sans KR', sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background-color: var(--white);
    overflow-x: hidden;
}

html {
    scroll-behavior: smooth;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background-color: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
    position: absolute;
    top: 0;
    width: 100%;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    font-size: 1.6rem;
    font-weight: 900;
    color: var(--white);
    text-decoration: none;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.header-logo {
    height: 40px;
    width: auto;
}

.nav {
    display: flex;
    gap: 30px;
}

.nav a {
    text-decoration: none;
    color: rgba(255, 255, 255, 0.85);
    font-weight: 600;
    transition: var(--transition);
    font-size: 1.05rem;
    position: relative;
    padding-bottom: 5px;
}

.nav a:hover {
    color: #9C27B0; /* Purple color */
}

.nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: var(--transition);
}

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

/* Burger Menu */
.burger-menu {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
    z-index: 1001;
}

.burger-menu span {
    width: 25px;
    height: 3px;
    background-color: var(--white);
    transition: all 0.3s ease;
}

/* Burger menu animation */
.burger-menu.toggle span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}
.burger-menu.toggle span:nth-child(2) {
    opacity: 0;
}
.burger-menu.toggle span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

/* Hero Section */
.hero {
    height: 100vh;
    background: linear-gradient(to right, rgba(10, 15, 30, 0.8), rgba(20, 30, 60, 0.6)), url('https://images.unsplash.com/photo-1581092334651-ddf26d9a09d0?ixlib=rb-4.0.3&auto=format&fit=crop&w=2000&q=80') center/cover no-repeat fixed;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding-top: 80px;
}

.hero-content h1 {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 25px;
    line-height: 1.3;
    letter-spacing: -1px;
    animation: fadeInUp 1s ease-out;
}

.hero-content p {
    font-size: 1.6rem;
    font-weight: 300;
    opacity: 0.9;
    letter-spacing: 2px;
    animation: fadeInUp 1s ease-out 0.3s backwards;
}

/* Hero Section for Multi-page */
.hero-section {
    position: relative;
    height: 350px;
    background-image: url('assets/hero-bg.png');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    text-align: center;
    padding-top: 80px; /* offset for absolute header */
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1;
}

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

.hero-content h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 10px;
}

.hero-content p {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.8);
}

/* Sections */
.section {
    padding: 100px 0;
}

.alt-bg {
    background-color: var(--bg-light);
}

.section-header {
    margin-bottom: 70px;
    position: relative;
    text-align: center;
}

.section-header h2 {
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.divider {
    width: 80px;
    height: 5px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: 3px;
    margin: 0 auto;
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text h3 {
    font-size: 2.2rem;
    color: var(--primary-color);
    margin-bottom: 20px;
    font-weight: 800;
}

.about-text .subtitle {
    font-size: 1.15rem;
    color: var(--text-light);
    margin-bottom: 40px;
    line-height: 1.8;
}

.info-list {
    list-style: none;
    background: var(--bg-light);
    padding: 30px;
    border-radius: 16px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.02);
}

.info-list li {
    padding: 15px 0;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    font-size: 1.05rem;
}

.info-list li:last-child {
    border-bottom: none;
}

.info-list li strong {
    width: 130px;
    color: var(--secondary-color);
    font-weight: 700;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
}

.feature-card {
    background: var(--white);
    padding: 40px 20px;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.04);
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.02);
}

.feature-card:hover {
    transform: translateY(-10px);
    border-color: var(--accent-color);
    box-shadow: 0 20px 50px rgba(33, 150, 243, 0.15);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    display: inline-block;
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    transform: scale(1.1);
}

.feature-card h4 {
    font-size: 1.3rem;
    margin-bottom: 12px;
    color: var(--secondary-color);
    font-weight: 700;
}

.feature-card p {
    color: var(--text-light);
    font-size: 1rem;
}

/* History Timeline */
.timeline {
    position: relative;
    max-width: 900px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    left: 150px;
    height: 100%;
    width: 2px;
    background: var(--border-color);
}

.timeline-item {
    display: flex;
    margin-bottom: 40px;
    position: relative;
    transition: var(--transition);
}

.timeline-item:hover {
    transform: translateX(10px);
}

.timeline-date {
    width: 150px;
    padding-right: 40px;
    text-align: right;
    font-weight: 800;
    color: var(--accent-color);
    font-size: 1.3rem;
    flex-shrink: 0;
    position: relative;
    padding-top: 15px;
}

.timeline-date::after {
    content: '';
    position: absolute;
    right: -8px;
    top: 20px;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--white);
    border: 4px solid var(--accent-color);
    z-index: 1;
    transition: var(--transition);
}

.timeline-item:hover .timeline-date::after {
    background: var(--accent-color);
    box-shadow: 0 0 10px rgba(33,150,243,0.5);
}

.timeline-content {
    padding-left: 40px;
    color: var(--text-dark);
    font-size: 1.1rem;
    background: var(--white);
    padding: 25px 35px;
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.04);
    width: 100%;
    margin-left: 20px;
    border-left: 4px solid transparent;
    transition: var(--transition);
}

.timeline-item:hover .timeline-content {
    border-left-color: var(--primary-color);
    box-shadow: 0 12px 35px rgba(0,0,0,0.08);
}

/* Organization Chart */
.org-section .section-header {
    margin-bottom: 100px;
}

.en-title {
    font-size: 4rem;
    font-weight: 900;
    color: rgba(0,0,0,0.03);
    margin-top: -55px;
    text-transform: uppercase;
    letter-spacing: 5px;
    position: absolute;
    width: 100%;
    left: 0;
    z-index: -1;
}

.org-chart {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-top: 60px;
}

.org-node {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 25px 45px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 15px 35px rgba(59, 43, 115, 0.25);
    min-width: 280px;
    transition: var(--transition);
}

.org-node:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 45px rgba(59, 43, 115, 0.35);
}

.org-node.ceo {
    display: flex;
    flex-direction: column;
    margin-bottom: 40px;
}

.org-node.ceo .role {
    font-size: 1.3rem;
    font-weight: 800;
    margin-bottom: 8px;
    letter-spacing: 2px;
}

.org-node.ceo .name {
    font-size: 1.1rem;
    opacity: 0.9;
}

.org-branch-main {
    width: 3px;
    height: 50px;
    background: var(--accent-color);
    opacity: 0.5;
}

.org-node.research {
    background: linear-gradient(135deg, #8e24aa, #5e35b1);
    margin-bottom: 40px;
    padding: 20px 40px;
}

.org-teams {
    display: flex;
    justify-content: space-between;
    width: 100%;
    gap: 25px;
    position: relative;
    padding-top: 40px;
}

.org-teams::before {
    content: '';
    position: absolute;
    top: 0;
    left: 10%;
    width: 80%;
    height: 3px;
    background: var(--accent-color);
    opacity: 0.5;
}

.org-node.team {
    flex: 1;
    min-width: 0;
    padding: 20px 10px;
    font-size: 1.05rem;
    font-weight: 700;
    background: var(--white);
    color: var(--primary-color);
    border: 2px solid var(--border-color);
    box-shadow: 0 10px 25px rgba(0,0,0,0.03);
    position: relative;
}

.org-node.team:hover {
    background: var(--primary-color);
    color: var(--white);
    border-color: var(--primary-color);
}

.org-node.team::before {
    content: '';
    position: absolute;
    top: -40px;
    left: 50%;
    transform: translateX(-50%);
    width: 3px;
    height: 40px;
    background: var(--accent-color);
    opacity: 0.5;
}

/* Partners Section */
.section-subtitle {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-top: 15px;
    font-weight: 500;
}

.partners-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.partner-card {
    background: var(--white);
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-dark);
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    height: 120px;
}

.partner-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.1);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.partner-card img {
    max-width: 80%;
    max-height: 80%;
    object-fit: contain;
}

/* Services Section */
.products-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    margin-top: 50px;
}

.product-card {
    background: var(--white);
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    border-top: 4px solid var(--accent-color);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.1);
}

.product-number {
    position: absolute;
    top: -10px;
    right: 20px;
    font-size: 5rem;
    font-weight: 900;
    color: rgba(33, 150, 243, 0.1);
    z-index: 0;
}

.product-img {
    width: 100%;
    height: 180px;
    object-fit: contain;
    margin-bottom: 20px;
    position: relative;
    z-index: 1;
}

.product-card h3 {
    font-size: 1.6rem;
    color: var(--primary-color);
    margin-bottom: 15px;
    position: relative;
    z-index: 1;
}

.product-card p {
    font-size: 1.1rem;
    color: var(--text-light);
    position: relative;
    z-index: 1;
}

/* ESG Section */
.esg-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.esg-card {
    background: var(--white);
    padding: 40px 30px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    text-align: center;
    transition: var(--transition);
    border-top: 4px solid transparent;
}

.esg-card.environment {
    border-top-color: #4CAF50;
}

.esg-card.social {
    border-top-color: #2196F3;
}

.esg-card.governance {
    border-top-color: #9C27B0;
}

.esg-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.1);
}

.esg-icon {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.esg-card h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.esg-card p {
    color: var(--text-light);
    font-size: 1.05rem;
}

/* Certifications Section */
.certs-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    margin-top: 50px;
}

.cert-card {
    background: linear-gradient(145deg, #ffffff, #f0f4f8);
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.cert-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.1);
    border-color: var(--secondary-color);
}

.cert-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.cert-card h3 {
    font-size: 1.4rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.cert-card p {
    color: var(--text-light);
    font-size: 1rem;
    margin-bottom: 20px;
    flex-grow: 1;
}

.cert-date {
    display: inline-block;
    background: var(--primary-color);
    color: var(--white);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 700;
}

/* Footer */
.footer {
    background-color: #111111;
    color: #999999;
    padding: 80px 0 30px;
}

.footer-info h3 {
    color: var(--white);
    font-size: 1.8rem;
    margin-bottom: 25px;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.contact-details {
    display: flex;
    gap: 40px;
    margin-top: 25px;
    flex-wrap: wrap;
}

.contact-details span {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.05rem;
}

.contact-details strong {
    color: var(--accent-color);
    font-weight: 700;
}

.footer-copyright {
    margin-top: 60px;
    padding-top: 25px;
    border-top: 1px solid #222222;
    text-align: center;
    font-size: 0.95rem;
    opacity: 0.7;
}

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

/* Responsive */
@media (max-width: 1024px) {
    .about-grid {
        grid-template-columns: 1fr;
        gap: 50px;
    }
    .about-text {
        text-align: center;
    }
    .info-list li {
        justify-content: center;
    }
    .org-teams {
        flex-wrap: wrap;
        justify-content: center;
    }
    .org-teams::before {
        display: none;
    }
    .org-node.team {
        flex: 0 0 calc(33.333% - 25px);
        margin-top: 20px;
    }
    .org-node.team::before {
        display: none;
    }
    .partners-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .esg-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .burger-menu {
        display: flex;
    }
    
    .nav {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: rgba(0, 0, 0, 0.9);
        backdrop-filter: blur(10px);
        padding: 20px 0;
        box-sizing: border-box;
        text-align: center;
        gap: 20px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    }
    
    .nav.active {
        display: flex;
    }
    .hero-content h1 {
        font-size: 2.8rem;
    }
    .hero-content p {
        font-size: 1.3rem;
    }
    .section {
        padding: 80px 0;
    }
    .section-header h2 {
        font-size: 2.2rem;
    }
    .timeline::before {
        left: 30px;
    }
    .timeline-date {
        width: 100%;
        text-align: left;
        padding-bottom: 15px;
        padding-left: 60px;
        padding-top: 0;
    }
    .timeline-date::after {
        left: 21px;
        top: 3px;
    }
    .timeline-item {
        flex-direction: column;
    }
    .timeline-content {
        margin-left: 60px;
        width: auto;
    }
    .timeline-item:hover {
        transform: none;
    }
    .org-node.team {
        flex: 0 0 calc(50% - 25px);
    }
    .partners-grid {
        grid-template-columns: 1fr;
    }
    .products-grid {
        grid-template-columns: 1fr;
    }
    .certs-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 576px) {
    .hero-content h1 {
        font-size: 2.2rem;
    }
    .about-features {
        grid-template-columns: 1fr;
    }
    .org-node.team {
        flex: 0 0 100%;
    }
    .contact-details {
        flex-direction: column;
        gap: 15px;
    }
    .org-node {
        min-width: 200px;
    }
}

/* ESG Policies Section */
.esg-policies-container {
    margin-top: 80px;
    padding-top: 60px;
    border-top: 1px solid rgba(0, 0, 0, 0.08);
}

.esg-policies-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
}

.policy-card {
    background: var(--white);
    border-radius: 12px;
    padding: 30px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.policy-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(59, 43, 115, 0.12);
    border-color: rgba(59, 43, 115, 0.2);
}

.policy-left {
    display: flex;
    align-items: center;
    gap: 20px;
}

.policy-icon {
    font-size: 2.2rem;
    width: 60px;
    height: 60px;
    background: var(--bg-light);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.policy-info h4 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.policy-info p {
    font-size: 0.9rem;
    color: var(--text-light);
}

.btn-download {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: linear-gradient(135deg, var(--primary-color), #5c44ab);
    color: var(--white);
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition);
    white-space: nowrap;
    box-shadow: 0 4px 12px rgba(59, 43, 115, 0.25);
}

.btn-download:hover {
    background: linear-gradient(135deg, #4b3891, #6c52c7);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(59, 43, 115, 0.35);
    color: var(--white);
}

/* Services Product Gallery Section */
.product-gallery-section {
    margin-top: 90px;
    padding-top: 70px;
    border-top: 1px solid rgba(0, 0, 0, 0.08);
}

.product-gallery-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 35px;
}

.gallery-card {
    background: var(--white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.06);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.gallery-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
    border-color: rgba(59, 43, 115, 0.25);
}

.gallery-img-wrapper {
    width: 100%;
    height: 320px;
    overflow: hidden;
    position: relative;
    background: #f8f9fa;
    display: flex;
    align-items: center;
    justify-content: center;
}

.gallery-img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.gallery-card:hover .gallery-img-wrapper img {
    transform: scale(1.05);
}

.gallery-info {
    padding: 24px 30px;
    text-align: center;
    background: var(--white);
    border-top: 1px solid var(--border-color);
}

.gallery-info h4 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: -0.3px;
}

@media (max-width: 992px) {
    .esg-policies-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .product-gallery-grid {
        grid-template-columns: 1fr;
    }
    .policy-card {
        flex-direction: column;
        align-items: flex-start;
        gap: 20px;
    }
    .btn-download {
        width: 100%;
        justify-content: center;
    }
}