/* RESET */
* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
    transition: all 0.5s ease-in;
}

/* ================= HEADER ================= */
header {
    background: #1A73E8; /* xanh chủ đạo */
    color: white;
    position: sticky;
    top: 0;
    z-index: 9999;
}

/* Top header */
.top-header {
    background: #0F5AD1; /* xanh đậm hơn */
    padding: 8px 0;
    color: #fff;
}

.top-header a {
    color: white;
    margin-left: 12px;
    font-size: 16px;
}

/* Main menu */
.main-menu {
    padding: 12px 0;
}

.nav-link {
    color: #fff !important;
    font-size: 17px;
    padding: 10px 18px;
    font-weight: 500;
}

.nav-link:hover {
    color: #dfeeff !important;
    text-decoration: underline;
}

.hamburger i { font-size: 28px; }

/* ================= MOBILE MENU ================= */
.mobile-menu {
    position: fixed;
    top: 0; right: -320px;
    width: 320px; height: 100vh;
    background: #1A73E8;
    padding: 40px 20px;
    box-shadow: -3px 0 8px rgba(0,0,0,0.3);
    transition: 0.3s;
    z-index: 999999;
}

.mobile-menu.show {
    right: 0;
}

.mobile-menu .close-btn {
    font-size: 45px;
    position: absolute;
    top: 15px; right: 20px;
    cursor: pointer;
    color: #fff;
}

.mobile-menu ul { list-style: none; padding: 0; margin-top: 60px; }
.mobile-menu ul li { margin-bottom: 22px; }
.mobile-menu ul li a {
    font-size: 22px;
    font-weight: bold;
    color: #fff;
    text-decoration: none;
}

/* ================= BANNER ================= */
.banner-carousel img {
    height: auto;
    object-fit: cover;
    width: 100%;
}

/* ================= BOX COMPONENT ================= */
.box {
    background: #fff;
    padding: 25px;
    text-align: center;
    border-radius: 14px;
    border: 1px solid #b7d4ff;
    box-shadow: 0 4px 12px rgba(26,115,232,0.08);
    transition: 0.2s;
}

.box:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 16px rgba(26,115,232,0.18);
}

/* ================= GALLERY ================= */
.tab-btn {
    padding: 10px 22px;
    border: none;
    background: #cde0ff;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
}

.tab-btn.active {
    background: #1A73E8;
    color: white;
}

.tab-image img {
    border-radius: 10px;
    box-shadow: 0 4px 14px rgba(26,115,232,0.18);
}

/* ================= BUTTONS ================= */
.btn-primary {
    background: #1A73E8;
    border: none;
    padding: 12px 24px;
    font-size: 18px;
    border-radius: 8px;
}

.btn-primary:hover {
    background: #0F5AD1;
}

/* ================= FORMS ================= */
form .form-control {
    padding: 12px;
    border-radius: 6px;
    border: 1px solid #b7d4ff;
}

/* ================= FOOTER ================= */
.footer {
    background: #0F5AD1;
    color: white;
}

.footer-social a {
    color: white;
    margin-right: 15px;
    font-size: 22px;
}

.bottom-footer {
    background: #0a3c8f;
    color: white;
    padding: 12px 0;
    font-size: 15px;
}

/* ================= RESPONSIVE ================= */
@media (max-width: 768px) {
    .banner-carousel img {
        height: auto;
    }
}

@media (max-width: 480px) {
    #header .top-header {
        display: none !important;
    }
    .main-menu{
        padding-left: 20px !important;
        padding-right: 20px !important;
    }
}

/* ================= SEO – HEADER IN HOA, XANH ĐẬM ================= */
h1, h2 {
    text-transform: uppercase;
    color: #0F5AD1; /* màu xanh đậm */
}

/* ================= BACKGROUND NỀN XEN KỸ ================= */
section:nth-child(odd) {
    background: #E8F1FF; /* nền xanh nhạt */
}

section:nth-child(even) {
    background: #d6e4f7; /* nền xanh nhẹ khác */
}

/* ================= ICON LIỆT KÊ - CHỨC NĂNG & LỢI ÍCH ================= */
.box h4 {
    position: relative;
    padding-left: 35px;
}

.box h4::before {
    content: "\f058"; /* FontAwesome check icon */
    font-family: 'Font Awesome 5 Free';
    font-weight: 900;
    position: absolute;
    left: 10px;
    top: 50%;
    transform: translateY(-50%);
    color: #1A73E8;
    font-size: 22px;
}

/* ================= CHỨC NĂNG, LỢI ÍCH – CANH GIỮA ICON VÀ CHỮ ================= */
.box {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

/* ================= FIX CHI TIẾT TINY CSS EFFECTS ================= */
footer .footer-social a {
    transition: color 0.3s ease;
}

footer .footer-social a:hover {
    color: #ff9800;
}