:root {
    --primary-color: #D01E12;
    --secondary-color: #fff;
    --text-color: #333;
    --light-bg: #f4f4f4;
    --white: #ffffff;
    --dark-red: #a01610;
}

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

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

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

/* Header */
header {
    background: #800000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.main-header {
    padding: 10px 0;
}

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

.logo-area {
    flex-shrink: 0;
}

.logo-area img {
    width: 100px;
    height: 100px;
    background: white;
    padding: 5px;
    border-radius: 50%;
    object-fit: contain;
}

.school-info {
    text-align: center;
    color: #fff;
    flex: 1;
}

.info-top {
    font-size: 0.9rem;
    text-transform: uppercase;
    color: #fff;
}

.school-name {
    font-family: 'Merriweather', serif;
    font-size: 1.8rem;
    font-weight: 700;
    margin: 5px 0;
    color: #fff;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}

.info-bottom p {
    font-size: 0.85rem;
    margin: 2px 0;
    color: #fff;
}

.info-bottom i {
    color: var(--secondary-color);
    margin-right: 5px;
}

.header-right {
    display: flex;
    align-items: center;
}

.search-box {
    display: flex;
    border: 1px solid #ddd;
    border-radius: 20px;
    overflow: hidden;
}

.search-box input {
    border: none;
    padding: 5px 10px;
    outline: none;
}

.search-box button {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: 5px 10px;
    cursor: pointer;
}

/* Navigation */
.main-nav {
    background: #B22222;
    color: #fff;
    border-top: 1px solid rgba(254, 196, 71, 0.3);
    padding: 0;
}

.nav-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0;
    padding: 0;
    margin: 0;
}

.nav-links li {
    position: relative;
    list-style: none;
}

.nav-links>li>a {
    display: block;
    padding: 15px 25px;
    font-weight: 500;
    transition: all 0.3s;
    font-size: 0.95rem;
    text-transform: capitalize;
    color: #fff;
    white-space: nowrap;
    letter-spacing: 0.5px;
}

.nav-links>li>a:hover,
.nav-links>li>a.active {
    background: rgba(254, 196, 71, 0.15);
    color: #FEC447;
    font-weight: 600;
}

/* Dropdown arrow removed */


/* Submenu styles */
.sub-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    color: #333;
    min-width: 220px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
    display: none;
    z-index: 1001;
    padding: 0;
    margin: 0;
    border-top: 3px solid var(--primary-color);
}

.nav-links li:hover>.sub-menu {
    display: block;
}

.sub-menu li {
    list-style: none;
}

.sub-menu li a {
    display: block;
    padding: 10px 15px;
    border-bottom: 1px solid #eee;
    color: #333;
    transition: all 0.3s;
    text-transform: none;
    font-size: 0.85rem;
    font-weight: normal;
}

.sub-menu li:last-child a {
    border-bottom: none;
}

.sub-menu li a:hover {
    background: #f0f0f0;
    color: var(--primary-color);
    padding-left: 20px;
}

/* Nested submenu */
.sub-menu li {
    position: relative;
}

.sub-menu li:has(.sub-menu)>a::after {
    content: '▶';
    float: right;
    font-size: 0.7rem;
    margin-left: 10px;
}

.sub-menu .sub-menu {
    left: 100%;
    top: 0;
    margin-top: -1px;
    border-top: none;
}


/* Hero Section */
.hero {
    height: 800px;
    /* background: url('z7369539714738_6c17b3681251eab7bc8d23272929ebfb.jpg') no-repeat center center/cover; */
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero h2 {
    font-family: 'Merriweather', serif;
    font-size: 3rem;
    margin-bottom: 10px;
}

.btn {
    display: inline-block;
    padding: 10px 30px;
    background: var(--secondary-color);
    color: white;
    border-radius: 25px;
    margin-top: 20px;
    transition: transform 0.3s;
}

.btn:hover {
    transform: scale(1.05);
}

/* Section Common */
section {
    padding: 60px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
}

.section-title h2 {
    color: var(--primary-color);
    font-size: 2rem;
    margin-bottom: 10px;
}

.line {
    width: 60px;
    height: 3px;
    background: var(--secondary-color);
    margin: 10px auto;
}


/* System Grid */
.education-system {
    padding: 60px 0;
}

.system-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.education-system .section-title h2 {
    color: #d32f2f;
    font-family: 'Roboto', sans-serif;
    font-weight: 500;
}

.education-system .line {
    background: #fbc02d;
    width: 50px;
    height: 3px;
}

.system-card {
    position: relative;
    height: 180px;
    background: #fff;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #333;
    text-align: center;
    overflow: hidden;
    border: 1px solid #eee;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.card-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-size: cover;
    background-position: center;
    transition: transform 0.5s;
    background-color: #fff;
    opacity: 0.15;
    filter: grayscale(100%);
}

.system-card:hover .card-bg {
    transform: scale(1.1);
    opacity: 0.25;
}

.system-card h3 {
    position: relative;
    z-index: 1;
    font-size: 1.1rem;
    color: #d32f2f;
    font-family: 'Merriweather', serif;
    font-weight: 700;
    padding: 0 15px;
    margin-bottom: 15px;
    text-shadow: none;
}

.card-bar {
    width: 90%;
    height: 8px;
    background: linear-gradient(110deg, #d32f2f 0%, #d32f2f 40%, #8d6e63 40%, #8d6e63 45%, #fbc02d 45%, #fbc02d 100%);
    position: absolute;
    bottom: 15px;
    z-index: 1;
    margin-top: 0;
}

@media (max-width: 992px) {
    .system-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 576px) {
    .system-grid {
        grid-template-columns: 1fr;
    }
}


/* News Grid */
.news {
    padding: 60px 0 !important;
    background: #ffffff !important;
    position: relative !important;
}

.news-slider-container {
    position: relative !important;
    width: 100% !important;
}

.news-nav {
    position: absolute !important;
    top: 50% !important;
    transform: translateY(-50%) !important;
    background: var(--primary-color) !important;
    border: none !important;
    width: 40px !important;
    height: 40px !important;
    border-radius: 50% !important;
    cursor: pointer !important;
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    font-size: 18px !important;
    color: white !important;
    transition: all 0.3s ease !important;
    z-index: 10 !important;
}

.news-nav:hover {
    background: var(--dark-red) !important;
    transform: translateY(-50%) scale(1.1) !important;
}

.news-nav.prev {
    left: -20px !important;
}

.news-nav.next {
    right: -20px !important;
}

.news-nav:disabled {
    opacity: 0.3 !important;
    cursor: not-allowed !important;
}

/* News Grid Container */
.news-grid {
    display: flex !important;
    flex-wrap: wrap !important;
    margin: 0 -15px !important;
    padding: 0 !important;
}

/* News Card Items */
.news-card {
    flex: 0 0 33.333333% !important;
    max-width: 33.333333% !important;
    padding: 0 15px !important;
    margin-bottom: 30px !important;
    box-sizing: border-box !important;
    background: transparent !important;
    border: none !important;
    box-shadow: none !important;
}

/* Responsive */
@media (max-width: 992px) {
    .news-card {
        flex: 0 0 50% !important;
        max-width: 50% !important;
    }
}

@media (max-width: 576px) {
    .news-card {
        flex: 0 0 100% !important;
        max-width: 100% !important;
    }
}

/* Hidden utility for slider */
.news-card.hidden {
    display: none;
}

.news-card:hover {
    transform: none !important;
    box-shadow: none !important;
}

.news-img {
    position: relative !important;
    background: #f0f0f0 !important;
    width: 100% !important;
    /* Aspect ratio approx 4:3 or 16:9 based on image */
    height: 240px !important;
    overflow: hidden !important;
}

.news-img img {
    width: 100% !important;
    height: 100% !important;
    object-fit: cover !important;
    display: block !important;
    transition: transform 0.5s ease !important;
}

.news-card:hover .news-img img {
    transform: scale(1.05) !important;
}

.news-content {
    padding: 15px 0 0 0 !important;
    /* Remove side padding, add top padding */
    flex: 1 !important;
    text-align: left !important;
}

.news-date {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.news-date i {
    font-size: 1rem;
}

.news-content h3 {
    font-size: 1.1rem !important;
    line-height: 1.4 !important;
    margin-bottom: 10px !important;
    font-weight: 700 !important;
    text-transform: uppercase !important;
}

.news-content h3 a {
    color: #a01610 !important;
    /* Dark red like screenshot */
    text-decoration: none !important;
    transition: color 0.3s !important;
}

.news-content h3 a:hover {
    color: #FEC447 !important;
}

.news-content p {
    display: none !important;
}

.news-heading {
    color: var(--primary-color) !important;
    font-size: 2rem !important;
    font-weight: 700 !important;
    margin-bottom: 10px !important;
    text-transform: uppercase !important;
}

.news-subheading {
    color: #999 !important;
    font-size: 0.95rem !important;
    font-weight: 400 !important;
    margin-bottom: 15px !important;
    text-transform: uppercase !important;
    letter-spacing: 1px !important;
}


/* Video Library */
.video-library {
    padding: 60px 0;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.video-card {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border-radius: 5px;
    overflow: hidden;
}

.video-info {
    padding: 15px;
}

.video-heading {
    color: var(--primary-color);
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.video-subheading {
    color: #666;
    font-size: 1rem;
    font-weight: 400;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}


/* Leadership */
.leadership {
    padding: 60px 0;
    background: #f9f9f9;
}

.leadership-grid {
    display: flex;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.leadership-card {
    text-align: center;
    max-width: 300px;
}

.leader-img img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid var(--white);
    box-shadow: 0 0 0 2px var(--primary-color);
}

.leader-name {
    color: var(--primary-color);
    margin-top: 15px;
    font-weight: 700;
}

.leadership-heading {
    color: var(--primary-color);
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.leadership-subheading {
    color: #666;
    font-size: 1rem;
    font-weight: 400;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Consultation */
.consultation {
    background: var(--light-bg);
    text-align: center;
}

.consult-form {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 20px;
}

.consult-form input {
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    width: 250px;
}

.consult-form button {
    padding: 10px 30px;
    background: var(--secondary-color);
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
}

/* Floating Widgets */
.floating-social {
    position: fixed;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    z-index: 999;
}

.social-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    margin-bottom: 5px;
    border-radius: 5px 0 0 5px;
}

.social-btn.youtube {
    background: #c4302b;
}

.social-btn.facebook {
    background: #3b5998;
}

.social-btn.zalo {
    background: #0088cc;
    font-size: 10px;
    font-weight: bold;
}

.consult-widget {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 999;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.robot-icon {
    position: relative;
    cursor: pointer;
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.robot-icon img {
    width: 60px;
    height: auto;
    animation: float 3s ease-in-out infinite;
    filter: drop-shadow(0 2px 5px rgba(0, 0, 0, 0.2));
}

.tooltip {
    position: absolute;
    right: 100%;
    top: 50%;
    transform: translateY(-50%);
    background: var(--primary-color);
    color: white;
    padding: 5px 10px;
    border-radius: 5px;
    font-size: 0.8rem;
    white-space: nowrap;
    margin-right: 10px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
}

.robot-icon:hover .tooltip {
    opacity: 1;
    visibility: visible;
}

@keyframes float {
    0% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-10px);
    }

    100% {
        transform: translateY(0px);
    }
}

.consult-btn {
    background: #e60000;
    color: white;
    padding: 10px 20px;
    border-radius: 20px;
    margin-bottom: 10px;
    font-weight: bold;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.zalo-chat-btn img {
    width: 50px;
    height: 50px;
}

/* Footer */
footer {
    background: var(--primary-color);
    color: white;
    padding-top: 40px;
}

.main-footer {
    padding-bottom: 40px;
}

.footer-content {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
}

.footer-info {
    flex: 2;
}

.footer-school-name {
    font-size: 1.2rem;
    margin-bottom: 20px;
    font-weight: 700;
}

.footer-map {
    flex: 1;
    min-width: 300px;
}

.contact-list li {
    margin-bottom: 10px;
}

.bottom-footer {
    background: var(--dark-green);
    padding: 15px 0;
    text-align: center;
}

.bottom-footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.footer-social .social-icon {
    color: white;
    margin: 0 5px;
    font-size: 1.1rem;
}

/* Burger */
.burger {
    display: none;
    cursor: pointer;
}

.burger div {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 5px;
    transition: all 0.3s ease;
}

/* Responsive */
@media screen and (max-width: 768px) {
    .nav-links {
        position: fixed;
        right: 0px;
        height: 100vh;
        top: 0;
        background-color: var(--white);
        display: flex;
        flex-direction: column;
        align-items: center;
        width: 60%;
        transform: translateX(100%);
        transition: transform 0.5s ease-in;
        z-index: 1001;
        justify-content: flex-start;
        padding-top: 80px;
        box-shadow: -2px 0 5px rgba(0, 0, 0, 0.2);
    }

    .nav-links li {
        opacity: 0;
        width: 100%;
        text-align: center;
    }

    .nav-links a {
        color: var(--text-color);
    }

    .burger {
        display: block;
        z-index: 1002;
    }

    .nav-active {
        transform: translateX(0%);
    }

    .sub-menu {
        position: static;
        display: none;
        width: 100%;
        box-shadow: none;
        background: #f9f9f9;
    }

    .nav-links li.active .sub-menu {
        display: block;
    }

    .header-content {
        flex-wrap: wrap;
    }

    .logo-area img {
        width: 60px;
        height: auto;
    }

    .school-name {
        font-size: 1.2rem;
        margin-left: 10px;
    }

    .school-info {
        text-align: left;
        flex: 1;
        margin-left: 10px;
    }

    .info-top {
        font-size: 0.7rem;
    }

    .info-bottom {
        display: none;
    }

    .search-box {
        display: none;
    }

    /* Hero Section Mobile */
    .hero {
        height: 400px !important;
    }

    .hero h2 {
        font-size: 1.5rem !important;
    }

    .hero p {
        font-size: 0.9rem;
        padding: 0 20px;
    }

    .hero-nav {
        width: 35px !important;
        height: 35px !important;
        font-size: 18px !important;
    }

    .hero-nav.prev {
        left: 10px !important;
    }

    .hero-nav.next {
        right: 10px !important;
    }

    .hero-dots {
        bottom: 15px;
    }

    .hero-dot {
        width: 8px;
        height: 8px;
    }

    .hero-dot.active {
        width: 20px;
    }

    /* Section Titles Mobile */
    .section-title h2,
    .news-heading,
    .video-heading,
    .leadership-heading {
        font-size: 1.3rem !important;
    }

    .news-subheading,
    .video-subheading,
    .leadership-subheading {
        font-size: 0.8rem !important;
    }

    /* Education System Mobile */
    .education-system {
        padding: 40px 0;
    }

    .system-card h3 {
        font-size: 0.95rem;
    }

    /* News Navigation Mobile */
    .news-nav {
        width: 30px !important;
        height: 30px !important;
        font-size: 14px !important;
    }

    .news-nav.prev {
        left: 0 !important;
    }

    .news-nav.next {
        right: 0 !important;
    }

    .news-img {
        height: 200px !important;
    }

    .news-content h3 {
        font-size: 0.95rem !important;
    }

    .news-date {
        font-size: 0.8rem;
    }

    /* Video Library Mobile */
    .video-library {
        padding: 40px 0;
    }

    .video-grid {
        grid-template-columns: 1fr !important;
        gap: 15px;
    }

    .video-nav {
        width: 30px !important;
        height: 30px !important;
        font-size: 14px !important;
    }

    .video-nav.prev {
        left: 0 !important;
    }

    .video-nav.next {
        right: 0 !important;
    }

    /* Leadership Mobile */
    .leadership {
        padding: 40px 0;
    }

    .leadership-grid {
        gap: 20px;
    }

    .leadership-card {
        max-width: 250px;
    }

    .leader-img img {
        width: 150px;
        height: 150px;
    }

    .leader-nav {
        width: 30px !important;
        height: 30px !important;
        font-size: 14px !important;
    }

    .leader-nav.prev {
        left: 0 !important;
    }

    .leader-nav.next {
        right: 0 !important;
    }

    /* Floating Widgets Mobile */
    .floating-social {
        right: 0;
        top: auto;
        bottom: 120px;
        transform: none;
    }

    .social-btn {
        width: 35px;
        height: 35px;
        font-size: 0.85rem;
    }

    .consult-widget {
        bottom: 10px;
        right: 10px;
    }

    .robot-icon img {
        width: 45px;
    }

    .consult-btn {
        font-size: 0.75rem;
        padding: 8px 12px;
        white-space: nowrap;
    }

    .zalo-chat-btn img {
        width: 40px;
        height: 40px;
    }

    .tooltip {
        display: none;
    }

    /* Footer Mobile */
    .footer-content {
        flex-direction: column;
    }

    .footer-map {
        min-width: 100%;
    }

    .footer-school-name {
        font-size: 1rem;
    }

    .contact-list li {
        font-size: 0.85rem;
    }

    .bottom-footer-content {
        flex-direction: column;
        gap: 10px;
    }

    .online-stats {
        font-size: 0.8rem;
    }
}

/* Extra small devices (phones in portrait, less than 576px) */
@media screen and (max-width: 576px) {
    .hero {
        height: 300px !important;
    }

    .hero h2 {
        font-size: 1.2rem !important;
    }

    .hero p {
        font-size: 0.8rem;
    }

    .btn {
        padding: 8px 20px;
        font-size: 0.85rem;
    }

    .container {
        padding: 0 15px;
    }

    .section-title h2 {
        font-size: 1.1rem !important;
    }

    .system-card {
        height: 150px;
    }

    .system-card h3 {
        font-size: 0.85rem;
    }

    .news,
    .video-library,
    .leadership,
    .education-system {
        padding: 30px 0 !important;
    }

    .consult-btn {
        font-size: 0.7rem;
        padding: 6px 10px;
    }

    /* Consultation Form Mobile */
    .consult-form {
        flex-direction: column;
        align-items: stretch;
    }

    .consult-form input {
        width: 100%;
        margin-bottom: 10px;
    }

    .consult-form button {
        width: 100%;
    }
}

@keyframes navLinkFade {
    from {
        opacity: 0;
        transform: translateX(50px);
    }

    to {
        opacity: 1;
        transform: translateX(0px);
    }
}

.toggle .line1 {
    transform: rotate(-45deg) translate(-5px, 6px);
}

.toggle .line2 {
    opacity: 0;
}

.toggle .line3 {
    transform: rotate(45deg) translate(-5px, -6px);
}