/* Biến màu sắc */
:root {
    --primary-color: #0A2463;
    --secondary-color: #E3B23C;
    --text-light: #ffffff;
    --text-dark: #333333;
    --background-light: #f4f4f4;
}

/* Thiết lập chung */
body {
    margin: 0;
    font-family: 'Arial', sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
}

/* Header - Phần đầu trang */
.site-header {
    position: fixed;
    top: 0;
    width: 100%;
    min-height: 60px; /* Chiều cao tối thiểu */
    background-color: var(--primary-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    padding: 10px 20px;
    box-sizing: border-box;
}

.header-top-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 40px;
}

.logo {
    font-size: 2.2em;
    font-weight: bold;
    color: var(--secondary-color);
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: color 0.3s ease;
}

.logo:hover {
    color: var(--text-light);
}

.nav-and-buttons-desktop {
    display: flex;
    align-items: center;
    gap: 20px;
}

/* Thanh điều hướng chính (Desktop) */
.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: 25px;
}

.main-nav a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: bold;
    padding: 8px 0;
    position: relative;
    transition: color 0.3s ease;
}

.main-nav a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 0%;
    height: 3px;
    background-color: var(--secondary-color);
    transition: width 0.3s ease;
}

.main-nav a:hover::after, .main-nav a.active::after {
    width: 100%;
}

.main-nav a:hover, .main-nav a.active {
    color: var(--secondary-color);
}

/* Nút hành động chung */
.header-buttons {
    display: flex;
    gap: 10px;
}

.btn {
    padding: 10px 20px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: bold;
    text-align: center;
    transition: all 0.3s ease;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    border: none;
    cursor: pointer;
}

.btn-primary {
    background-color: var(--secondary-color);
    color: var(--primary-color);
    border: 2px solid var(--secondary-color);
}

.btn-primary:hover {
    background-color: #d8a632;
    color: var(--text-light);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3), 0 0 15px var(--secondary-color);
}

.btn-secondary {
    background-color: var(--primary-color);
    color: var(--secondary-color);
    border: 2px solid var(--secondary-color);
}

.btn-secondary:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3), 0 0 15px var(--secondary-color);
}

/* Hamburger Menu (Mobile Only) */
.hamburger-menu {
    display: none; /* Ẩn trên desktop */
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
    z-index: 1001; /* Đảm bảo luôn trên cùng */
}

.hamburger-menu span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--secondary-color);
    margin: 5px 0;
    transition: 0.4s;
}

.hamburger-menu.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

.hamburger-menu.active span:nth-child(2) {
    opacity: 0;
}

.hamburger-menu.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

/* Menu di động */
.nav-menu-mobile {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: var(--primary-color);
    transform: translateX(-100%); /* Ẩn ban đầu */
    transition: transform 0.4s ease-in-out;
    z-index: 1001;
    padding-top: 80px; /* Đẩy xuống dưới header */
    box-sizing: border-box;
    overflow-y: auto;
}

.nav-menu-mobile.active {
    transform: translateX(0%); /* Hiển thị */
}

.nav-menu-mobile ul {
    list-style: none;
    padding: 0;
    margin: 0;
    text-align: center;
}

.nav-menu-mobile li {
    margin-bottom: 20px;
}

.nav-menu-mobile a {
    color: var(--text-light);
    text-decoration: none;
    font-size: 1.5em;
    font-weight: bold;
    padding: 10px 20px;
    display: block;
    transition: background-color 0.3s ease;
}

.nav-menu-mobile a:hover {
    background-color: rgba(227, 178, 60, 0.2);
}

.mobile-buttons {
    display: none; /* Ẩn trên desktop */
    justify-content: center;
    padding: 10px 0;
    background-color: var(--primary-color);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    z-index: 1000; /* Dưới menu mobile */
}

/* Footer - Phần chân trang */
.site-footer {
    background-color: var(--primary-color);
    color: var(--text-light);
    padding: 40px 20px;
    margin-top: 50px;
}

.footer-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
    padding-bottom: 30px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section h3 {
    color: var(--secondary-color);
    font-size: 1.3em;
    margin-bottom: 15px;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 5px;
    display: inline-block;
}

.footer-section p, .footer-section ul {
    font-size: 0.95em;
    line-height: 1.8;
    margin: 0;
    padding: 0;
}

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

.footer-section a {
    color: var(--text-light);
    text-decoration: none;
    transition: color 0.3s ease;
    display: block;
    padding: 3px 0;
}

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

.footer-bottom {
    text-align: center;
    margin-top: 20px;
    font-size: 0.85em;
    color: rgba(255, 255, 255, 0.7);
}

.copyright {
    margin: 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .site-header {
        padding: 5px 10px;
        min-height: auto;
    }

    .header-top-row {
        justify-content: space-between;
        min-height: 50px;
    }

    .logo {
        flex-grow: 1;
        text-align: center;
        font-size: 1.8em;
    }

    .nav-and-buttons-desktop {
        display: none;
    }

    .hamburger-menu {
        display: block;
        color: var(--secondary-color);
        order: -1; /* Đẩy hamburger sang trái */
    }

    .mobile-buttons {
        display: flex;
        flex-wrap: wrap;
        gap: 8px;
        justify-content: center;
        padding: 8px 10px;
        box-shadow: none;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
    }

    .mobile-buttons .btn {
        flex: 1 1 auto;
        min-width: 120px; /* Đảm bảo nút không quá nhỏ */
        padding: 8px 15px;
        font-size: 0.9em;
    }

    .footer-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-section h3 {
        margin-top: 20px;
    }

    .footer-section ul {
        padding-left: 0;
    }

    .footer-section a {
        display: inline-block;
        margin: 0 10px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.6em;
    }

    .mobile-buttons .btn {
        min-width: unset;
        width: 100%;
    }
}