body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
}
.header {
    background-color: #E91E63; 
    color: white;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between; 
    align-items: center;
}
.logo {
    font-size: 28px;
    font-weight: bold;
}
.nav a {
    color: white;
    text-decoration: none;
    margin: 0 10px;
    font-size: 16px;
}
.nav a.active {
    font-weight: bold;
    border-bottom: 2px solid white;
}
.container {
    padding: 20px 30px;
}
h1 {
    color: #333;
}
.subscribe-btn {
    background-color: #ff4081; 
    color: white;
    padding: 10px 15px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    font-size: 14px;
}
.subscribe-btn:hover {
    background-color: #e0004c; 
}
.content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px; 
}
.post-card {
    background-color: white;
    border: 1px solid #eee;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    overflow: hidden; 
    transition: transform 0.2s;
}
.post-card:hover {
    transform: translateY(-5px);
}
.post-card h3 {
    color: #E91E63;
    font-size: 18px;
    padding: 15px;
    margin: 0;
}
.post-card p {
    font-size: 14px;
    padding: 0 15px 15px;
    margin: 0;
    color: #555;
}
@media (max-width: 768px) {
    .header {
        flex-direction: column;
        gap: 15px;
    }
}
.featured-categories {
    margin-bottom: 20px;
}
.featured-categories h2 {
    font-size: 24px;
    color: #333;
    border-bottom: 2px solid #E91E63;
    padding-bottom: 5px;
    margin-bottom: 15px;
}
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}
.category-card {
    background-color: #fff;
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    text-decoration: none;
    color: #333;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    transition: transform 0.2s, box-shadow 0.2s;
}
.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    color: #E91E63;
}
.category-card h3 {
    margin: 0 0 5px 0;
    color: #E91E63;
}
.category-card p {
    font-size: 14px;
    color: #666;
    margin: 0;
}
.product-submenu {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 20px;
}
.category-link {
    background-color: #f0f0f0;
    color: #333;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
}
.category-link:hover {
    background-color: #E91E63;
    color: white;
}
.header {
    background-color: #E91E63;
    color: white;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap; 
    gap: 20px;
}
.header-left, .header-right {
    display: flex;
    align-items: center;
    gap: 25px;
    flex-wrap: wrap;
}
.search-container {
    display: flex; 
}
.search-container input[type="text"] {
    padding: 9px 12px;
    font-size: 14px;
    border: none;
    border-radius: 5px 0 0 5px; 
    outline: none; 
    min-width: 200px; 
}
.search-container button {
    padding: 9px 12px;
    border: none;
    background-color: #f0f0f0; 
    color: #333;
    cursor: pointer;
    border-radius: 0 5px 5px 0; 
    font-size: 14px;
    font-weight: bold;
}
.search-container button:hover {
    background-color: #ddd;
}
.support-banner {
    background-color: #E91E63; 
    background-image: linear-gradient(to right, #E91E63, #c2185b);
    color: white;
    padding: 30px;
    border-radius: 8px;
    margin-bottom: 20px;
    text-align: center;
}
.support-layout {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 20px;
}
.form-table {
    width: 100%;
    border-collapse: collapse;
}
.form-table td {
    padding: 12px 5px;
    border-bottom: 1px solid #f0f0f0;
}
.form-table td:first-child {
    width: 120px; 
    font-weight: bold;
    color: #333;
    vertical-align: top;
    padding-top: 20px;
}
.form-table input[type="text"],
.form-table input[type="email"],
.form-table input[type="tel"],
.form-table select,
.form-table textarea {
    width: 100%;
    padding: 10px;
    font-size: 14px;
    border: 1px solid #ccc;
    border-radius: 5px;
    box-sizing: border-box; 
}
.btn-submit {
    background-color: #E91E63;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    font-size: 16px;
    transition: background-color 0.2s;
}
.btn-submit:hover {
    background-color: #c2185b;
}
.contact-info-title {
    color: #E91E63;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
}
.contact-info-list {
    list-style-type: none;
    padding: 0;
    margin: 10px 0 0 0;
}
.contact-info-list li {
    margin-bottom: 10px;
    color: #555;
}
.contact-info-list.simple-list li {
    display: flex;
    justify-content: space-between;
}
.contact-info-list.simple-list span {
    font-weight: bold;
    color: #333;
}
.faq-section {
    margin-top: 20px;
}
.faq-item {
    border: 1px solid #eee;
    border-radius: 5px;
    margin-bottom: 10px;
    background-color: #f9f9f9;
}
.faq-item summary {
    padding: 15px;
    font-weight: bold;
    cursor: pointer;
    list-style: none; 
}
.faq-item summary::-webkit-details-marker {
    display: none; 
}
.faq-answer {
    padding: 15px;
    border-top: 1px solid #eee;
    background-color: #fff;
    color: #333;
}
@media (max-width: 768px) {
    .support-layout {
        grid-template-columns: 1fr;
    }
}
.product-banner {
    background-color: #E91E63;
    background-image: linear-gradient(to right, #E91E63, #c2185b);
    color: white;
    padding: 30px;
    text-align: center;
    margin-bottom: 20px;
}
.product-banner h1 {
    color: white;
    margin: 0;
}
.product-layout {
    display: grid;
    grid-template-columns: 1fr 3fr;
    gap: 20px;
}
.product-sidebar h3 {
    color: #333;
    font-size: 18px;
    border-bottom: 1px solid #eee;
    padding-bottom: 8px;
    margin: 20px 0 10px 0;
}
.product-sidebar .post-card {
    padding: 15px;
    position: sticky;
    top: 20px;
}
.filter-title {
    margin-top: 20px;
}
.category-list {
    list-style-type: decimal;
    padding-left: 20px;
}
.category-list li {
    margin-bottom: 8px;
}
.category-list a {
    text-decoration: none;
    color: #333;
    display: block;
    padding: 8px 10px;
    border-radius: 5px;
}
.category-list a:hover {
    background-color: #f4f4f4;
}
.category-list a.active {
    background-color: #fde7f0;
    color: #E91E63;
    font-weight: bold;
}
.price-filter-list {
    list-style-type: none; 
    padding-left: 0;
}
.price-filter-list li {
    margin-bottom: 8px;
    padding: 5px;
}
.price-filter-list label {
    cursor: pointer;
}
.product-card {
    background-color: white;
    border: 1px solid #eee;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}
.product-card .card-image-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 1 / 1; 
    overflow: hidden;
}
.product-card img {
    width: 100%;
    height: 100%;
    object-fit: cover; 
}
.product-card .badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background-color: #e53935; 
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: bold;
    z-index: 10;
}
.product-card .product-info {
    padding: 15px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}
.product-card h3 {
    font-size: 16px;
    color: #333;
    margin: 0 0 8px 0;
}
.product-card .rating {
    font-size: 14px;
    color: #555;
    margin-bottom: 8px;
}
.product-card .price-box {
    margin-bottom: 12px;
}
.product-card .price-new {
    font-size: 18px;
    font-weight: bold;
    color: #e53935;
    margin-right: 8px;
}
.product-card .price-old {
    font-size: 14px;
    color: #999;
    text-decoration: line-through;
}
.product-card .btn-add-cart {
    background-color: #E91E63;
    color: white;
    padding: 10px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    font-size: 14px;
    text-align: center;
    margin-top: auto; 
}
@media (max-width: 768px) {
    .product-layout {
        grid-template-columns: 1fr;
    }
}
.promo-banner {
    background-image: linear-gradient(to right, #ef4444, #ec4899);
    color: white;
    padding: 40px 20px;
    text-align: center;
    margin-bottom: 20px;
}
.promo-banner h1 {
    color: white;
    margin: 0 0 10px 0;
}
.promo-banner p {
    font-size: 1.2em;
    opacity: 0.9;
    margin-bottom: 20px;
}
.countdown-timer {
    display: flex;
    justify-content: center;
    gap: 15px;
}
.timer-box {
    background: white;
    color: #333;
    border-radius: 8px;
    padding: 10px;
    min-width: 70px;
}
.timer-value {
    font-size: 2em;
    font-weight: bold;
    color: #ef4444;
}
.timer-label {
    font-size: 0.9em;
    color: #555;
}
.stock-progress {
    background-color: #fce7f3;
    height: 15px;
    overflow: hidden;
    position: relative;
    margin-bottom: 10px;
}
.progress-bar {
    background-color: #ef4444; 
    height: 100%;
}
.stock-progress span {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    color: #333;
    font-size: 10px;
    font-weight: bold;
    line-height: 15px;
}
.voucher-grid {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}
.voucher-card {
    background: #fff;
    border: 2px dashed #f9a8d4;
    border-radius: 8px;
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
}
.voucher-icon {
    font-size: 2.5em;
}
.voucher-info h3 {
    margin: 0 0 5px 0;
    color: #333;
}
.voucher-info p {
    margin: 0;
    color: #555;
}
.btn-copy {
    background-color: #fdf2f8;
    color: #E91E63;
    border: 1px solid #E91E63;
    padding: 8px 12px;
    border-radius: 5px;
    font-weight: bold;
    cursor: pointer;
}
.deal-banner {
    background-color: #fef3c7;
    border: 1px solid #fcd34d;
    color: #ca8a04;
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    margin-bottom: 20px;
}
.news-banner {
    background-color: #4f46e5;
    background-image: linear-gradient(to right, #4f46e5, #a855f7);
    color: white;
    padding: 30px;
    text-align: center;
    margin-bottom: 20px;
}
.news-banner h1 {
    color: white;
    margin: 0 0 10px 0;
}
.news-banner p {
    font-size: 1.1em;
    opacity: 0.9;
    margin: 0;
}
.news-layout {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 20px;
}

.featured-news-card h2 {
    font-size: 1.8em;
    color: #333;
    margin: 0 0 10px 0;
}
.featured-news-card .product-info {
    padding: 20px;
}
.featured-news-card .excerpt {
    font-size: 1.1em;
    color: #555;
    margin-bottom: 15px;
}
.read-more-link {
    color: #4f46e5;
    font-weight: bold;
    text-decoration: none;
}
.read-more-link.small {
    font-size: 0.9em;
}
.news-meta {
    display: flex;
    gap: 15px;
    font-size: 0.9em;
    color: #555;
    margin-bottom: 10px;
}
.news-meta.small {
    font-size: 0.8em;
    gap: 10px;
}
.news-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}
.news-grid .product-info {
    padding: 15px;
}
.news-grid h3 {
    font-size: 1.1em;
    color: #333;
}
.sidebar-widget {
    padding: 15px;
    margin-bottom: 20px;
}
.sidebar-widget h3 {
    color: #333;
    font-size: 1.2em;
    border-bottom: 1px solid #eee;
    padding-bottom: 8px;
    margin-bottom: 15px;
}
.category-list-ol {
    list-style-type: decimal;
    padding-left: 20px;
}
.category-list-ol li {
    margin-bottom: 8px;
}
.category-list-ol a {
    text-decoration: none;
    color: #333;
    font-weight: bold;
}
.category-list-ol a:hover {
    color: #E91E63;
}
.popular-post-list-ul {
    list-style-type: none;
    padding-left: 0;
    margin: 0;
}
.popular-post-item {
    display: flex;
    gap: 10px;
    align-items: center;
    text-decoration: none;
    margin-bottom: 10px;
}
.popular-post-item img {
    width: 60px;
    height: 60px;
    object-fit: cover;
    border-radius: 5px;
    flex-shrink: 0;
}
.popular-post-item h4 {
    font-size: 0.9em;
    color: #333;
    margin: 0 0 5px 0;
}
.popular-post-item span {
    font-size: 0.8em;
    color: #555;
}
.section-title {
    color: #333;
    border-bottom: 2px solid #E91E63;
    padding-bottom: 5px;
    margin-top: 30px;
    margin-bottom: 20px;
}
.video-wrapper {
    position: relative;
    padding-bottom: 56.25%; 
    height: 0;
    overflow: hidden;
}
.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}
.audio-player audio {
    width: 100%;
}
.social-links {
    display: flex;
    flex-direction: column; 
    gap: 10px;
}
.social-link {
    display: block;
    padding: 10px 15px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    color: white;
    text-align: center;
}
.social-link.facebook { background-color: #1877F2; }
.social-link.youtube { background-color: #FF0000; }
.social-link.website { background-color: #555; }
@media (max-width: 768px) {
    .news-layout {
        grid-template-columns: 1fr;
    }
}
.card-image-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.product-banner {
    background-color: #E91E63;
    background-image: linear-gradient(to right, #E91E63, #c2185b);
    color: white;
    padding: 30px;
    text-align: center;
    margin-bottom: 20px;
}
.product-banner h1 {
    color: white;
    margin: 0;
}
.product-layout {
    display: grid;
    grid-template-columns: 1fr 3fr;
    gap: 20px;
}
.product-sidebar h3 {
    color: #333;
    font-size: 18px;
    border-bottom: 1px solid #eee;
    padding-bottom: 8px;
    margin: 20px 0 10px 0;
}
.product-sidebar .post-card {
    padding: 15px;
    position: sticky;
    top: 20px;
}
.filter-title {
    margin-top: 20px;
}
.category-list {
    list-style-type: decimal;
    padding-left: 20px;
}
.category-list li {
    margin-bottom: 8px;
}
.category-list a {
    text-decoration: none;
    color: #333;
    display: block;
    padding: 8px 10px;
    border-radius: 5px;
}
.category-list a:hover {
    background-color: #f4f4f4;
}
.category-list a.active {
    background-color: #fde7f0; 
    color: #E91E63;
    font-weight: bold;
}
.price-filter-list {
    list-style-type: none; 
    padding-left: 0;
}
.price-filter-list li {
    margin-bottom: 8px;
    padding: 5px;
}
.price-filter-list label {
    cursor: pointer;
}
.product-card {
    background-color: white;
    border: 1px solid #eee;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.product-card .card-image-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 1 / 1;
    overflow: hidden;
}
.product-card img {
    width: 100%;
    height: 100%;
    object-fit: cover; 
}
.product-card .badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background-color: #e53935;
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: bold;
    z-index: 10;
}
.product-card .product-info {
    padding: 15px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}
.product-card h3 {
    font-size: 16px;
    color: #333;
    margin: 0 0 8px 0;
}
.product-card .rating {
    font-size: 14px;
    color: #555;
    margin-bottom: 8px;
}
.product-card .price-box {
    margin-bottom: 12px;
}
.product-card .price-new {
    font-size: 18px;
    font-weight: bold;
    color: #e53935; 
    margin-right: 8px;
}
.product-card .price-old {
    font-size: 14px;
    color: #999;
    text-decoration: line-through;
}
.product-card .btn-add-cart {
    background-color: #E91E63; 
    color: white;
    padding: 10px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    font-size: 14px;
    text-align: center;
    margin-top: auto; 
}
@media (max-width: 768px) {
    .product-layout {
        grid-template-columns: 1fr;
    }
}
/* ---  CHO MÃ SỐ SINH VIÊN --- */
.student-id-badge {
    background-color: rgba(255, 255, 255, 0.2); 
    color: white;
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: bold;
    display: inline-block;
    margin-top: 15px;
    border: 1px solid rgba(255, 255, 255, 0.5);
}