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

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    background-color: #f5f5f5;
}


.container {
    width: 90%;
    max-width: 1000px; 
    margin: 0 auto;
}


header {
    background-color: #fff;
    padding: 10px 0;
    text-align: center;
}
.header-content {
    display: flex;
    align-items: center;
    gap: 10px;
}
.logo {
    color: #333;
    font-weight: bold;
}
.slogan {
    color: #666;
    border-left: 2px solid #ccc;
    padding-left: 10px;
    margin-left: 10px;
}


nav {
    background-color: #333;
}
.menu {
    list-style: none;
    display: flex;
}
.menu li a {
    display: block;
    color: white;
    padding: 15px 20px;
    text-decoration: none;
    font-weight: bold;
    text-transform: uppercase;
    transition: 0.3s;
}
.menu li a:hover, .menu li a.active {
    background-color: #000;
    color: white;
}


.banner {
    background: none;      
    padding: 20px 0;       
    text-align: center;   
}


.full-banner {
    width: 100%;           
    max-width: 100%;
    height: auto;          
    display: block;
    border-radius: 10px;   
    box-shadow: 0 4px 8px rgba(0,0,0,0.1); 
}


.section-title {
    background-color: #0056b3; 
    color: white;
    padding: 10px;
    text-transform: uppercase;
    margin-bottom: 20px;
    border-radius: 5px;
}

.product-grid {
    display: flex;
    justify-content: space-between; 
    gap: 20px;
    margin-bottom: 40px;
    flex-wrap: wrap; 
}


.product-card {
    background: white;
    border-radius: 10px;
    padding: 15px;
    width: 32%; 
    position: relative; 
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: left;
    margin-bottom: 20px; 
}


.badge {
    position: absolute;
    top: 10px;
    left: 10px;
    color: white;
    padding: 5px 10px;
    font-size: 12px;
    font-weight: bold;
    border-radius: 20px;
    z-index: 10;
}
.badge.hot { background-color: red; }
.badge.sale { background-color: #dc3545; }
.badge.new { background-color: #dc3545; }

.card-img {
    background-color: #e0f7fa; 
    border-radius: 10px;
    margin-bottom: 15px;
    text-align: center;
    padding: 20px 0;
}
.card-img img {
    max-width: 80%;
    height: auto;
}

.card-info h4 {
    font-size: 16px;
    margin-bottom: 5px;
    color: #333;
}
.price {
    color: #d0021b; 
    font-weight: bold;
    font-size: 18px;
    margin-bottom: 5px;
}
.rating {
    color: #ffcc00; 
    margin-bottom: 10px;
}
.btn-buy {
    background-color: #ffcc00; 
    color: black;
    border: none;
    padding: 8px 20px;
    font-weight: bold;
    cursor: pointer;
    border-radius: 5px;
}
.btn-buy:hover {
    background-color: #e6b800;
}


footer {
    background-color: #002b5e; 
    color: white;
    padding: 20px 0;
    font-size: 14px;
    display: flex;
    justify-content: space-between;
}
footer .container {
    display: flex;
    justify-content: space-between;
}
.contact-email {
    color: #ffcc00;
}

.contact-form {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    max-width: 600px;
    margin: 0 auto; 
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #333;
}

.form-group input, 
.form-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 16px;
}

.form-group textarea {
    height: 100px;
}

.btn-submit {
    background-color: #0056b3;
    color: white;
    border: none;
    padding: 10px 30px;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    font-size: 16px;
}

.btn-submit:hover {
    background-color: #004494;
}










/*product.html*/
.header-content {
    display: flex;
    justify-content: space-between; 
    align-items: center;
    padding: 10px 0;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 10px;
}

.header-right p {
    font-size: 13px;
    color: #888;
    text-align: right; 
}


nav {
    background-color: #333; 
}

.menu {
    display: flex;
    list-style: none;
}

.menu li a {
    display: block;
    color: white;
    padding: 12px 25px;
    text-decoration: none;
    font-weight: bold;
    text-transform: uppercase;
}

.menu li.active a, 
.menu li a:hover {
    background-color: #000; 
}


.page-container {
    display: flex;
    gap: 20px;
    margin-top: 30px;
    margin-bottom: 50px;
    align-items: flex-start;
}

.sidebar {
    width: 25%;
    flex-shrink: 0;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    overflow: hidden;
}

.sidebar-title {
    background-color: #f1f1f1;
    padding: 15px;
    font-weight: bold;
    color: #0056b3; 
    text-transform: uppercase;
    font-size: 14px;
    border-bottom: 1px solid #ddd;
}

.sidebar-menu li a {
    display: block;
    padding: 12px 15px 12px 30px; 
    color: #0056b3;
    font-weight: bold;
    text-decoration: none;
    border-bottom: 1px solid #eee;
    transition: 0.3s;
    font-size: 14px;
}

.sidebar-menu li a:hover {
    background-color: #0056b3;
    color: white;
    padding-left: 40px;
}

.main-product-list {
    width: 75%;
}

.list-header {
    background-color: #0056b3;
    color: white;
    padding: 10px 15px;
    border-radius: 5px;
    text-transform: uppercase;
    font-weight: bold;
    margin-bottom: 20px;
}

.product-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: flex-start;
}

.product-card {
    width: calc(33.33% - 10px);
    background: white;
    border-radius: 10px;
    padding: 15px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 15px;
}

.product-card h4 {
    color: #0056b3;
    font-weight: bold;
    margin: 10px 0;
    font-size: 15px;
    min-height: 40px;
}

.price {
    color: #d9534f;
    font-weight: bold;
    font-size: 17px;
}

.btn-buy {
    background-color: #ffc107;
    border: none;
    padding: 10px;
    width: 100%;
    border-radius: 5px;
    font-weight: bold;
    cursor: pointer;
}





/*Contact.html*/
.contact-wrapper {
    display: flex;
    gap: 30px;
    margin-bottom: 50px;
}

.contact-left {
    width: 55%; 
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.contact-right {
    width: 45%;
}

.contact-title {
    background-color: #0056b3;
    color: white;
    padding: 10px 15px;
    border-radius: 5px;
    text-transform: uppercase;
    font-weight: bold;
    margin-bottom: 20px;
}


.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    font-weight: bold;
    margin-bottom: 5px;
    color: #333;
}

.form-group input, 
.form-group select, 
.form-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-family: inherit;
    font-size: 14px;
    transition: 0.3s;
}


.form-group input:focus, 
.form-group select:focus, 
.form-group textarea:focus {
    border-color: #ff7e5f; 
    outline: none;
    box-shadow: 0 0 5px rgba(255, 126, 95, 0.3);
}

.btn-submit {
    background-color: #004080;
    color: white;
    border: none;
    padding: 10px 25px;
    border-radius: 4px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s;
}

.btn-submit:hover {
    background-color: #002b5e;
}


.map-box {
    width: 100%;
    height: 300px;
    background: #eee;
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 20px;
}

.store-info {
    line-height: 1.8;
    color: #555;
}

.store-info i {
    color: #0056b3;
    margin-right: 10px;
}



/* =========================================
   CSS CHO MENU DROPDOWN (DANH SÁCH BÀI LAB)
   ========================================= */

/* 1. Thiết lập vùng neo cho menu chính chứa Dropdown */
.menu .dropdown {
    position: relative; /* Dùng làm gốc tọa độ cho menu con */
}

/* 2. Tạo hình dáng và ẩn menu con (Danh sách 8 bài Lab) đi */
.dropdown-content {
    display: none; /* Mặc định ẩn */
    position: absolute;
    background-color: #333; /* Khớp màu với thanh menu chính */
    min-width: 200px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.5); /* Đổ bóng tạo chiều sâu */
    z-index: 999; /* Đảm bảo menu xổ xuống luôn nằm đè lên hình ảnh phía dưới */
    padding: 0;
    margin: 0;
    top: 100%; /* Neo sát mép dưới của menu chính */
    left: 0;
}

/* 3. Tinh chỉnh các nút bấm bên trong menu con */
.dropdown-content li {
    width: 100%;
}

.dropdown-content li a {
    padding: 12px 20px;
    display: block;
    text-transform: none; /* Giữ nguyên chữ thường cho dễ đọc tên bài Lab */
    font-size: 14px;
    border-bottom: 1px solid #444; /* Vạch kẻ ngang phân cách nhẹ nhàng */
}

/* 4. Đổi màu nút khi rê chuột (Hover) */
.dropdown-content li a:hover {
    background-color: #000;
    color: white;
}

/* 5. HIỆU ỨNG THUẬT TOÁN: Hiển thị menu con khi rê chuột vào thư mục cha */
.menu .dropdown:hover .dropdown-content {
    display: block;
}