/* ===================================
   GLOBAL STYLES & RESET
   =================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-navy: #1a3a5c;
    --primary-dark: #0f2438;
    --secondary-blue: #2c5f8d;
    --accent-orange: #ff6b35;
    --accent-teal: #20b2aa;
    --white: #ffffff;
    --light-gray: #f5f7fa;
    --medium-gray: #e0e5eb;
    --text-dark: #2c3e50;
    --text-light: #6c757d;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
    overflow-x: hidden;
}

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

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

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

/* ===================================
   LANGUAGE SWITCHER
   =================================== */
.language-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    display: flex;
    gap: 10px;
    background: var(--white);
    padding: 8px;
    border-radius: 25px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.lang-btn {
    padding: 10px 20px;
    border: 2px solid var(--primary-navy);
    background: var(--white);
    color: var(--primary-navy);
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.lang-btn:hover {
    background: var(--light-gray);
    transform: translateY(-2px);
}

.lang-btn.active {
    background: var(--primary-navy);
    color: var(--white);
}

.lang-btn i {
    font-size: 16px;
}

/* ===================================
   NAVIGATION
   =================================== */
.navbar {
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 999;
    padding: 15px 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 15px;
}

.nav-logo {
    height: 50px;
    width: auto;
}

.nav-brand h2 {
    color: var(--primary-navy);
    font-size: 24px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.nav-menu a.active {
    color: var(--accent-orange);
    background: var(--light-gray);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
    align-items: center;
}

.nav-menu a {
    color: var(--text-dark);
    font-weight: 500;
    font-size: 15px;
    padding: 8px 15px;
    border-radius: 5px;
    transition: all 0.3s ease;
}

.nav-menu a:hover {
    color: var(--primary-navy);
    background: var(--light-gray);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--primary-navy);
    cursor: pointer;
}

/* ===================================
   HERO SLIDER
   =================================== */
.hero-slider {
    position: relative;
    height: 100vh;
    min-height: 600px;
    overflow: hidden;
}

.slider-container {
    width: 100%;
    height: 100%;
    position: relative;
}

.slide {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

.slide.active {
    opacity: 1;
}

.slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.slide-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(26, 58, 92, 0.85), rgba(44, 95, 141, 0.75));
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-content {
    text-align: center;
    color: var(--white);
    max-width: 800px;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 56px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-content p {
    font-size: 20px;
    margin-bottom: 35px;
    opacity: 0.95;
}

.btn-primary {
    display: inline-block;
    padding: 15px 40px;
    background: var(--accent-orange);
    color: var(--white);
    font-weight: 600;
    border-radius: 50px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(255, 107, 53, 0.3);
}

.btn-primary:hover {
    background: #e55a2b;
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(255, 107, 53, 0.4);
}

/* Slider Controls */
.slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.3);
    color: var(--white);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    z-index: 10;
    backdrop-filter: blur(10px);
}

.slider-btn:hover {
    background: rgba(255, 255, 255, 0.5);
    transform: translateY(-50%) scale(1.1);
}

.slider-btn.prev {
    left: 30px;
}

.slider-btn.next {
    right: 30px;
}

.slider-dots {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 10;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: all 0.3s ease;
}

.dot.active,
.dot:hover {
    background: var(--white);
    transform: scale(1.3);
}

/* ===================================
   ANIMATIONS
   =================================== */
.fade-in {
    animation: fadeIn 1s ease-out;
}

.fade-in-delay {
    animation: fadeIn 1s ease-out 0.3s both;
}

.fade-in-delay-2 {
    animation: fadeIn 1s ease-out 0.6s both;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease-out;
}

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

/* ===================================
   STATISTICS SECTION
   =================================== */
.stats-section {
    background: var(--primary-navy);
    color: var(--white);
    padding: 60px 0;
    margin-top: -5px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    text-align: center;
}

.stat-item {
    padding: 20px;
}

.stat-number {
    font-size: 48px;
    font-weight: 700;
    color: var(--accent-orange);
    margin-bottom: 10px;
}

.stat-item p {
    font-size: 16px;
    opacity: 0.9;
    font-weight: 500;
}

/* ===================================
   SECTION HEADERS
   =================================== */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 42px;
    color: var(--primary-navy);
    font-weight: 700;
    margin-bottom: 15px;
}

.section-divider {
    width: 80px;
    height: 4px;
    background: var(--accent-orange);
    margin: 0 auto;
    border-radius: 2px;
}

/* ===================================
   ABOUT SECTION
   =================================== */
.about-section {
    padding: 80px 0;
    background: var(--white);
}

.about-text {
    max-width: 900px;
    margin: 0 auto;
}

.about-text h3 {
    font-size: 28px;
    color: var(--primary-navy);
    margin-bottom: 20px;
}

.about-text p {
    font-size: 18px;
    line-height: 1.8;
    color: var(--text-light);
}

/* ===================================
   ENTITIES SECTION
   =================================== */
.entities-section {
    padding: 80px 0;
    background: var(--light-gray);
}

.entities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

.entity-card {
    background: var(--white);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
}

.entity-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.entity-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.entity-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.entity-card:hover .entity-image img {
    transform: scale(1.1);
}

.entity-badge {
    position: absolute;
    top: 20px;
    right: 20px;
    background: var(--accent-orange);
    color: var(--white);
    padding: 8px 20px;
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
}

.entity-badge-investment {
    background: var(--accent-teal);
}

.entity-badge-production {
    background: var(--primary-navy);
}

.entity-content {
    padding: 30px;
}

.entity-content h3 {
    font-size: 22px;
    color: var(--primary-navy);
    margin-bottom: 10px;
    font-weight: 700;
}

.entity-subtitle {
    font-size: 16px;
    color: var(--text-light);
    margin-bottom: 15px;
    font-style: italic;
}

.entity-type {
    font-size: 14px;
    color: var(--accent-orange);
    font-weight: 600;
    margin-bottom: 20px;
}

.entity-features,
.entity-products {
    list-style: none;
    margin: 20px 0;
}

.entity-features li,
.entity-products li {
    padding: 8px 0;
    padding-left: 25px;
    position: relative;
    font-size: 15px;
    color: var(--text-dark);
}

.entity-features li:before,
.entity-products li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--accent-teal);
    font-weight: bold;
}

.entity-highlight {
    background: linear-gradient(135deg, var(--primary-navy), var(--secondary-blue));
    color: var(--white);
    padding: 20px;
    border-radius: 10px;
    margin: 20px 0;
    text-align: center;
}

.entity-highlight p {
    font-weight: 600;
    font-size: 15px;
}

.entity-content h4 {
    font-size: 18px;
    color: var(--primary-navy);
    margin: 25px 0 15px;
    font-weight: 600;
}

.entity-contact-info {
    background: var(--light-gray);
    padding: 15px;
    border-radius: 8px;
    margin: 20px 0;
    font-size: 14px;
}

.entity-contact-info p {
    margin: 8px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.entity-contact-info i {
    color: var(--accent-orange);
}

/* ===================================
   SERVICES SECTION
   =================================== */
.services-section {
    padding: 80px 0;
    background: var(--white);
}

.service-block {
    background: var(--light-gray);
    border-radius: 15px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
}

.service-header {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 30px;
}

.service-header i {
    font-size: 42px;
    color: var(--accent-orange);
}

.service-header h3 {
    font-size: 32px;
    color: var(--primary-navy);
    font-weight: 700;
}

.service-list {
    list-style: none;
}

.service-list li {
    padding: 15px 0;
    padding-left: 30px;
    position: relative;
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-dark);
    border-bottom: 1px solid var(--medium-gray);
}

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

.service-list li:before {
    content: "►";
    position: absolute;
    left: 0;
    color: var(--accent-teal);
    font-size: 14px;
}

.service-image {
    margin: 30px 0;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.service-image img {
    width: 100%;
    height: 400px;
    object-fit: cover;
}

/* ===================================
   ORGANIZATION SECTION
   =================================== */
.organization-section {
    padding: 80px 0;
    background: var(--light-gray);
}

.org-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.org-card {
    background: var(--white);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
}

.org-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.org-card i {
    font-size: 48px;
    color: var(--accent-orange);
    margin-bottom: 20px;
}

.org-card h3 {
    font-size: 24px;
    color: var(--primary-navy);
    margin-bottom: 20px;
    font-weight: 700;
}

.org-card p {
    font-size: 15px;
    line-height: 1.7;
    color: var(--text-dark);
    margin-bottom: 20px;
}

.org-card ul {
    list-style: none;
}

.org-card ul li {
    padding: 10px 0;
    padding-left: 25px;
    position: relative;
    font-size: 15px;
    color: var(--text-dark);
}

.org-card ul li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--accent-teal);
    font-size: 20px;
}

/* ===================================
   PARTICIPATION SECTION
   =================================== */
.participation-section {
    padding: 80px 0;
    background: var(--white);
}

.participation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
    gap: 40px;
}

.participation-card {
    background: linear-gradient(135deg, var(--primary-navy), var(--secondary-blue));
    color: var(--white);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.participation-card h3 {
    font-size: 26px;
    margin-bottom: 25px;
    font-weight: 700;
    color: var(--accent-orange);
}

.participation-card ul {
    list-style: none;
}

.participation-card ul li {
    padding: 12px 0;
    padding-left: 30px;
    position: relative;
    font-size: 16px;
    line-height: 1.6;
}

.participation-card ul li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--accent-orange);
    font-weight: bold;
    font-size: 18px;
}

/* ===================================
   PRODUCTS SECTION
   =================================== */
.products-section {
    padding: 80px 0;
    background: var(--light-gray);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.product-card {
    background: var(--white);
    padding: 40px 30px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
}

.product-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px rgba(0,0,0,0.15);
}

.product-card i {
    font-size: 52px;
    color: var(--accent-orange);
    margin-bottom: 20px;
}

.product-card h3 {
    font-size: 20px;
    color: var(--primary-navy);
    font-weight: 600;
}

/* ===================================
   CONTACT SECTION
   =================================== */
.contact-section {
    padding: 80px 0;
    background: var(--white);
}

.contact-content {
    max-width: 900px;
    margin: 0 auto;
}

.contact-main {
    background: var(--light-gray);
    padding: 40px;
    border-radius: 15px;
    margin-bottom: 40px;
}

.contact-main h3 {
    font-size: 26px;
    color: var(--primary-navy);
    margin-bottom: 10px;
    font-weight: 700;
}

.company-name-vi {
    font-size: 20px;
    color: var(--text-light);
    margin-bottom: 30px;
    font-weight: 600;
}

.contact-details {
    display: grid;
    gap: 25px;
}

.contact-item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.contact-item i {
    font-size: 24px;
    color: var(--accent-orange);
    margin-top: 5px;
}

.contact-item strong {
    display: block;
    color: var(--primary-navy);
    margin-bottom: 5px;
    font-size: 16px;
}

.contact-item p {
    color: var(--text-dark);
    font-size: 15px;
    line-height: 1.6;
}

.contact-persons {
    background: var(--primary-navy);
    color: var(--white);
    padding: 40px;
    border-radius: 15px;
}

.contact-persons h4 {
    font-size: 24px;
    margin-bottom: 30px;
    color: var(--accent-orange);
    font-weight: 700;
}

.person-card {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    padding: 20px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    margin-bottom: 20px;
}

.person-card:last-child {
    margin-bottom: 0;
}

.person-card i {
    font-size: 32px;
    color: var(--accent-orange);
}

.person-card p {
    margin: 5px 0;
    font-size: 15px;
}

.person-card strong {
    font-size: 18px;
}

/* ===================================
   FOOTER
   =================================== */
.footer {
    background: var(--primary-dark);
    color: var(--white);
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    height: 60px;
    width: auto;
    margin-bottom: 15px;
}

.footer-section h4 {
    font-size: 20px;
    margin-bottom: 20px;
    color: var(--accent-orange);
    font-weight: 700;
}

.footer-section p,
.footer-section li {
    font-size: 14px;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 10px;
}

.footer-section ul {
    list-style: none;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--accent-orange);
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    font-size: 14px;
    opacity: 0.7;
}

/* ===================================
   BACK TO TOP BUTTON
   =================================== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--accent-orange);
    color: var(--white);
    border: none;
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 998;
    box-shadow: 0 4px 15px rgba(255, 107, 53, 0.3);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-navy);
    transform: translateY(-5px);
}

/* ===================================
   RESPONSIVE DESIGN
   =================================== */
@media (max-width: 768px) {
    .language-switcher {
        top: 10px;
        right: 10px;
        padding: 5px;
    }
    
    .lang-btn {
        padding: 8px 15px;
        font-size: 12px;
    }
    
    .lang-btn span {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        background: var(--white);
        width: 100%;
        padding: 20px;
        box-shadow: 0 5px 20px rgba(0,0,0,0.1);
        transition: left 0.3s ease;
        gap: 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-menu li {
        width: 100%;
        margin: 10px 0;
    }
    
    .nav-menu a {
        display: block;
        padding: 15px;
    }
    
    .hero-content h1 {
        font-size: 36px;
    }
    
    .hero-content p {
        font-size: 16px;
    }
    
    .slider-btn {
        width: 40px;
        height: 40px;
        font-size: 16px;
    }
    
    .slider-btn.prev {
        left: 15px;
    }
    
    .slider-btn.next {
        right: 15px;
    }
    
    .section-header h2 {
        font-size: 32px;
    }
    
    .entities-grid,
    .org-grid,
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .participation-grid {
        grid-template-columns: 1fr;
    }
    
    .service-header {
        flex-direction: column;
        text-align: center;
    }
    
    .service-header h3 {
        font-size: 24px;
    }
    
    .service-image img {
        height: 250px;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 28px;
    }
    
    .hero-content p {
        font-size: 14px;
    }
    
    .stat-number {
        font-size: 36px;
    }
    
    .entity-content,
    .org-card,
    .contact-main,
    .contact-persons {
        padding: 25px;
    }
    
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 45px;
        height: 45px;
    }
}