:root {
    --primary-blue: #0056b3;
    --primary-dark: #003d82;
    --accent-red: #f51616;
    --accent-orange: #ed7f20;
    --light-blue: #b0dbb396;
    --text-dark: #0056b3;
    --text-light: #000;
    --white: #ffffff;
    --gold: #d4af37;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.16);
    --transition: all 0.3s ease;
    --border-radius: 12px;
}

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

body {
    font-family:  sans-serif,'Roboto';
    color: #000;
	background-image: url(bg-header.png);
    /*background-color: var(--white);*/
    line-height: 1.6;
    font-size: 16px;
    overflow-x: hidden;
}
 h1 {
    font-family: 'Merriweather', serif;
    font-size: 2.8rem;
    margin-bottom: 10px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    position: relative;
}
h2, h3, h4, h5 {
    font-family: serif, 'Playfair Display';
    font-weight: 700;
    color: var(--primary-blue);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header & Navigation */
header {
    background-image: url('bg-header.png');
    background-repeat: no-repeat;
    background-position: center top;
    background-size: cover;
    padding: 5px 0;
    background-color: var(--white);
    box-shadow: 0 5px 10px #ed7f20;
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    flex-wrap: wrap;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 0 1 auto;
    min-width: 280px;
}

.logo {
    height: 80px;
    width: 80px;
    min-width: 60px;
    border-radius: 50%;
    overflow: hidden;
    border: 2px solid #edc709;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

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

.logo-text {
    display: flex;
    flex-direction: column;
    flex: 1;
}

.logo-text h1 {
    font-size: 1.1rem;
    margin-bottom: 3px;
    color: var(--primary-blue);
    line-height: 1.3;
}

.logo-text p {
    font-size: 1rem;
    color: #f51616;
}

.anniversary-badge {
    background-color: var(--accent-red);
    color: var(--white);
    padding: 6px 18px;
    border-radius: 20px;
    font-weight: bold;
    font-size: 0.8rem;
    margin-left: 5px;
    white-space: nowrap;
}

/* Navigation */
.mobile-menu-btn {
    display: block;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--light-blue);
    cursor: pointer;
    padding: 5px;
    z-index: 1001;
}
.mobile-menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: none;
    border: 2px solid var(--light-blue);
    border-radius: 8px;
    color: var(--primary-blue);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
}

.mobile-menu-btn:hover {
    background: var(--primary-blue);
    color: var(--white);
}

nav {
    display: none;
    width: 100%;
    margin-top: 20px;
}

nav.active {
    display: block;
    animation: slideDown 0.3s ease-out;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

nav ul {
    display: flex;
    flex-direction: column;
    gap: 8px;
    background: var(--white);
    padding: 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    list-style: none;
}

nav a {
    display: block;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    color: var(--primary-blue);
    text-decoration: none;
    font-weight: 600;
    border-radius: 8px;
    transition: var(--transition);
}

nav a:hover {
    color: var(--accent-red);
}
nav a.active {
    border: 1px solid var(--accent-red);
    color: var(--accent-red);
}

/* Hero Banner */
.hero-banner {
    background: linear-gradient(#ef2c2c, #a50606);
    color: var(--white);
    padding: 40px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid #ed7f20;
    margin-top: 0;
}

.hero-content {
    max-width: 100%;
    margin: 0 auto;
    padding: 0 10px;
    font-size: 1.2rem;
}

.hero-content h2 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--white);
    line-height: 1.3;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 25px;
    opacity: 0.95;
    text-align: center;
}

.countdown {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 25px;
    flex-wrap: wrap;
}

.countdown-item {
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    padding: 12px 5px;
    min-width: 65px;
    flex: 1;
    max-width: 75px;
}

.countdown-number {
    font-size: 1.3rem;
    font-weight: bold;
    display: block;
}

.countdown-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    opacity: 0.9;
}

/* Main Content Sections */
section {
    padding: 40px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 25px;
    position: relative;
}

.section-title h2 {
    font-size: 1.5rem;
    display: inline-block;
    padding-bottom: 15px;
}

.section-title h2::after {
    content: '';
    position: absolute;
    width: 30%;
    height: 3px;
    background-color: var(--accent-red);
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
}

.section-intro {
    text-align: center;
    max-width: 100%;
    margin: 0 auto 30px;
    font-size: 1.05rem;
    color: var(--text-light);
    padding: 0 10px;
}

/* Tradition Section */
.tradition-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}

.tradition-card {
    background-color: var(--white);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s, box-shadow 0.3s;
}

.tradition-img {
    height: 180px;
    width: 100%;
    object-fit: cover;
}

.tradition-content {
    padding: 20px;
}

.tradition-content h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
    color: var(--primary-blue);
}

.tradition-content h5 {
    font-size: 1rem;
    margin: 15px 0 8px;
    color: var(--accent-red);
}

.tradition-content p {
    color: #000;
    margin-bottom: 12px;
    font-size: 1.05rem;
    text-align: justify;
}

/* History Timeline */
.history-timeline {
    position: relative;
    padding-left: 15px;
    margin: 20px 0;
}

.history-timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background-color: var(--primary-blue);
}

.timeline-phase {
    position: relative;
    margin-bottom: 20px;
}

.timeline-phase::before {
    content: '';
    position: absolute;
    left: -21px;
    top: 5px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--accent-red);
    border: 2px solid var(--white);
    box-shadow: 0 0 0 2px var(--accent-red);
}

.highlight-date {
    color: var(--accent-red);
    font-weight: 600;
    font-size: 1.05rem;
}

.highlight-text {
    background-color: #b0dbb396;
    padding: 12px;
    border-radius: 5px;
    border-left: 3px solid var(--accent-red);
    margin: 15px 0;
    font-size: 1.05rem;
}

/* Achievements Section */
.achievements-section {
    background-color: #a4edb7;
}

.achievements-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin-bottom: 30px;
}

.achievement-item {
    text-align: center;
    padding: 15px 10px;
    background-color: rgba(255, 255, 255, 0.8);
    border-radius: 8px;
}

.achievement-icon {
    font-size: 1.8rem;
    color: var(--primary-blue);
    margin-bottom: 10px;
}

.achievement-number {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--accent-red);
    display: block;
    margin-bottom: 5px;
}

.achievement-text {
    font-size: 0.85rem;
    color: var(--text-dark);
}

.achievement-timeline {
    max-width: 100%;
    margin: 0 auto;
}

.timeline-item {
    display: flex;
    flex-direction: column;
    margin-bottom: 25px;
    position: relative;
}

.timeline-year {
    background-color: var(--primary-blue);
    color: var(--white);
    padding: 10px 15px;
    border-radius: 5px;
    font-weight: bold;
    text-align: center;
    position: relative;
    z-index: 1;
    margin-bottom: 15px;
}

.timeline-content {
    background-color: var(--white);
    padding: 15px;
    border-radius: 5px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.08);
}

.timeline-content h3 {
    font-size: 1.1rem;
    margin-bottom: 10px;
}

/* Vision Section */
.vision-content {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.vision-text h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
}

.vision-text p {
    margin-bottom: 15px;
    font-size: 1.05rem;
    text-align: justify;
}

.vision-text ul {
    margin-left: 20px;
    margin-bottom: 20px;
}

.vision-text li {
    margin-bottom: 8px;
    text-align: justify;
}

.vision-image {
    width: 100%;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.vision-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* Event Info Section */
.event-section {
    background-color: var(--primary-blue);
    color: var(--white);
}

.event-section .section-title h2 {
    color: var(--white);
}

.event-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}

.event-card {
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    backdrop-filter: blur(5px);
    transition: background-color 0.3s;
	border: 1px solid #fff; /*rgba(255, 255, 255, 0.2);*/
}

.event-icon {
    font-size: 1.8rem;
    margin-bottom: 15px;
    color: #94d5cc;
}

.event-card h3 {
    color: var(--white);
    margin-bottom: 12px;
    font-size: 1.2rem;
/*
	border: 2px solid #fff;
	color: #yellow;
	padding: 15px;
	border-radius: 8px;
	margin: 20px 0;
	display: center;
	align-items: center;
	*/
    font-family: Arial, sans-serif;
}

.event-card p {
    opacity: 0.9;
    margin-bottom: 8px;
    font-size: 1.05rem;
    text-align: justify;
}

/* Footer */
footer {
    background-color: #002a5c;
    color: var(--white);
    padding: 30px 0 20px;
    border-top: 1px solid #ed7f20;
}

.footer-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 25px;
    margin-bottom: 25px;
}

.footer-logo {
    text-align: center;
}

.footer-logo h3 {
    color: var(--white);
    margin: 15px 0 10px;
    font-size: 1.2rem;
}

.footer-logo p {
    font-size: 0.9rem;
    margin-bottom: 8px;
}

.footer-contact h4, .footer-links h4 {
    color: var(--white); 
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.footer-contact p {
    margin-bottom: 8px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    font-size: 0.9rem;
}

.footer-contact i {
    margin-top: 3px;
    min-width: 16px;
}

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

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: #cccccc;
    text-decoration: none;
    transition: color 0.3s;
    font-size: 0.9rem;
    display: block;
    padding: 5px 0;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: #fff;
    font-size: 0.85rem;
}

/* Music Player */
.music-player {
    position: fixed;
    bottom: 15px;
    right: 15px;
    z-index: 10000;
    background-color: rgba(0, 86, 179, 0.95);
    color: white;
    border-radius: 50px;
    padding: 8px 12px;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(5px);
    transition: all 0.3s ease;
    min-width: 50px;
}

.music-btn {
    background: none;
    border: none;
    color: white;
    font-size: 1rem;
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.music-info {
    font-size: 0.8rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 120px;
    display: none;
}

.volume-slider {
    width: 50px;
    height: 4px;
    -webkit-appearance: none;
    appearance: none;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 2px;
    outline: none;
    display: none;
}

/* Back to top button */
.back-to-top {
    position: fixed;
    bottom: 70px;
    right: 15px;
    background-color: var(--primary-blue);
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    cursor: pointer;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.2);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    z-index: 999;
}

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

/* Responsive Design */
@media (min-width: 576px) {
    .logo-text h1 {
        font-size: 1.2rem;
    }
    
    .hero-content h2 {
        font-size: 1.8rem;
    }
    
    .hero-content p {
        font-size: 1.05rem;
    }
    
    .countdown-item {
        min-width: 75px;
        max-width: 85px;
        padding: 15px 8px;
    }
    
    .countdown-number {
        font-size: 1.5rem;
    }
    
    .section-title h2 {
        font-size: 1.8rem;
    }
    
    .tradition-container {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .achievements-container {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .event-container {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-container {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .music-player {
        padding: 10px 15px;
    }
}

@media (min-width: 768px) {
    .mobile-menu-btn {
        display: none;
    }
    
    nav {
        display: block;
        width: auto;
        order: 0;
        margin-top: 0;
    }
    
    nav ul {
        flex-direction: row;
        background: none;
        box-shadow: none;
        padding: 0;
    }
    
    nav li {
        width: auto;
    }
    
    nav a {
        padding: 5px 10px;
        width: auto;
        background: none;
    }
    
    nav a:hover {
        background: none;
    }
    
    .logo-section {
        min-width: auto;
    }
    
    .hero-content h2 {
        font-size: 2.2rem;
    }
    
    .hero-content p {
        font-size: 1.1rem;
        max-width: 800px;
        margin: 0 auto 25px;
    }
    
    .countdown-item {
        min-width: 90px;
        max-width: 100px;
        padding: 20px 10px;
    }
    
    .countdown-number {
        font-size: 2rem;
    }
    
    .timeline-item {
        flex-direction: row;
        align-items: flex-start;
    }
    
    .timeline-year {
        margin-bottom: 0;
        margin-right: 20px;
        min-width: 130px;
    }
    
    .timeline-content {
        flex: 1;
        position: relative;
    }
    
    .timeline-content::before {
        content: '';
        position: absolute;
        left: -10px;
        top: 15px;
        width: 0;
        height: 0;
        border-top: 10px solid transparent;
        border-bottom: 10px solid transparent;
        border-right: 10px solid var(--white);
    }
    
    .vision-content {
        flex-direction: row;
        align-items: flex-start;
    }
    
    .vision-text {
        flex: 1;
    }
    
    .vision-image {
        flex: 1;
    }
    
    .event-container {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .footer-container {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .music-info {
        display: block;
    }
    
    .volume-slider {
        display: block;
    }
}

@media (min-width: 992px) {
    section {
        padding: 60px 0;
    }
    
    .hero-banner {
        padding: 60px 0;
    }
    
    .hero-content h2 {
        font-size: 2.5rem;
    }
    
    .section-title h2 {
        font-size: 2.2rem;
    }
    
    .tradition-container {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Animation for countdown */
@keyframes countdownPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

.countdown-item {
    animation: countdownPulse 2s infinite;
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 800px;
    margin: 0 auto;
}

.awards-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(450px, 1fr));
    gap: 25px;
    margin-bottom: 40px;
}

@media (max-width: 768px) {
    .awards-container {
        grid-template-columns: 1fr;
    }
}

.award-card {
    background-color: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 2px solid #d32f2f;
    display: flex;
    align-items: flex-start;
}

.award-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 25px rgba(0, 0, 0, 0.15);
}

.award-icon {
    background-color: #ffebee;
    color: #d32f2f;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 20px;
    flex-shrink: 0;
    font-size: 1.8rem;
}

.award-content h3 {
    font-family: serif,'Merriweather';
    color: #b30000;
    margin-bottom: 10px;
    font-size: 1.4rem;
}

.award-content p {
    color: #000;
    font-size: 1.05rem;
    text-align: justify;
}

.highlight {
    color: #d32f2f;
    font-weight: 500;
}

.badge {
    display: inline-block;
    background-color: #ffebee;
    color: #d32f2f;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 0.9rem;
    margin-top: 8px;
    font-weight: 500;
}

.school-name {
    font-weight: bold;
    color: #b30000;
}

.ribbon {
    position: absolute;
    top: -10px;
    right: -10px;
    width: 120px;
    height: 120px;
    overflow: hidden;
}

.ribbon span {
    position: absolute;
    top: 40px;
    right: -30px;
    transform: rotate(45deg);
    width: 170px;
    background-color: #ffd700;
    color: #b30000;
    text-align: center;
    font-weight: bold;
    padding: 8px 0;
    font-size: 0.9rem;
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
}
.thanhtuu {
    text-align: center;
    margin-bottom: 40px;
    padding: 30px;
    background: linear-gradient(135deg, #f50808, #f3ce13);/*linear-gradient(135deg, #b30000, #d32f2f);*/
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    color: white;
    position: relative;
    overflow: hidden;
}

.thanhtuu::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
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