:root {
    --brand-blue: #0052CC;
    --brand-blue-dark: #003E99;
    --brand-yellow: #FFC400;
    --text-primary: #172B4D;
    --text-secondary: #5E6C84;
    --bg-light: #FFFFFF;
    --bg-secondary: #F4F5F7;
    --border-color: #DFE1E6;
    --font-global: 'Open Sans', sans-serif;
}

* { margin:0; padding:0; box-sizing:border-box; }
html { scroll-padding-top: 80px; }
body {
    font-family: var(--font-global);
    background-color: var(--bg-light);
    color: var(--text-primary);
    line-height: 1.7;
    scroll-behavior: smooth;
}

.container { width: 90%; max-width: 1200px; margin: 0 auto; }
.section-padding { padding: 80px 0; }
.section-bg { background-color: var(--bg-secondary); }
h1, h2, h3, h4 { font-weight: 700; color: var(--text-primary); }
a { color: var(--brand-blue); text-decoration: none; transition: color .3s }
a:hover { color: var(--brand-blue-dark); }

/* Reset .page-link */
.page-link{
    border: 0 !important;
}

.page-item.active .page-link{
    background-color: var(--brand-blue) !important;
}

.nav-links {
    margin: 0;
}

.nav-links a{
    font-size: 16px;
}

.nav-links a:hover{
    text-decoration: none;
}

    /* Buttons */
.btn {
    display:inline-block; padding:12px 24px; border-radius:8px; font-weight:700;
    border:none; cursor:pointer; transition:.3s; font-family: var(--font-global); font-size:.95rem; text-align:center;
}
.btn-primary{ background:var(--brand-blue); color:#fff; box-shadow:0 4px 15px rgba(0,82,204,.15); }
.btn-primary:hover{ transform:translateY(-2px); background:var(--brand-blue-dark); box-shadow:0 6px 20px rgba(0,82,204,.2); }
.btn-secondary{ background:transparent; color:var(--brand-blue); border:2px solid var(--brand-blue); }
.btn-secondary:hover{ background:var(--brand-blue); color:#fff; }

/* Footer (dùng chung) */
.main-footer{ background: var(--text-primary); padding: 50px 5%; color: #a7b3c4; }
.footer-grid{ display:grid; grid-template-columns: repeat(auto-fit, minmax(220px,1fr)); gap:2rem; max-width:1200px; margin:0 auto;}
.footer-col h4{ margin-bottom:1.5rem; color:#fff; }
.footer-col ul{ list-style:none; }
.footer-col ul li{ margin-bottom:.8rem; }
.footer-col ul a{ color: var(--text-secondary); }
.footer-col ul a:hover{ color:#fff; }
.social-links{ display:flex; gap:1rem; margin-top:1rem; }
.social-links a{ font-size:1.5rem; color: var(--text-secondary); }
.social-links a:hover{ color:#fff; }
.footer-bottom{ text-align:center; margin-top:3rem; padding-top:1.5rem; border-top:1px solid rgba(173,181,189,.2); font-size:.9rem; }

/* Scroll to Top */
#scroll-to-top{
    position:fixed; bottom:20px; right:20px; width:50px; height:50px; background:var(--brand-blue); color:#fff;
    border:none; border-radius:50%; display:flex; align-items:center; justify-content:center; font-size:1.5rem; cursor:pointer;
    box-shadow:0 4px 10px rgba(0,0,0,.2); opacity:0; visibility:hidden; transition: opacity .3s, visibility .3s, transform .3s; transform: translateY(20px); z-index:999;
}
#scroll-to-top.visible{ opacity:1; visibility:visible; transform: translateY(0); }

/* CTA Section */
.cta-section {
    background-color: var(--brand-blue);
    color: var(--bg-light);
    border-radius: 15px;
    text-align: center;
    padding: 60px 30px;
}
.cta-section h2, .cta-section p {
    color: var(--bg-light);
}
.cta-section .btn {
    background-color: var(--bg-light);
    color: var(--brand-blue);
}


/* Header & Navigation */
.main-header {
    position: sticky;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    padding: 0 5%;
    border-bottom: 1px solid var(--border-color);
    height: 80px;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-logo img {
    height: 40px;
}

.nav-desktop {
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 10px;
    align-items: center;
}

.nav-links a {
    color: var(--text-primary);
    font-weight: 600;
    padding: 8px 16px;
    position: relative;
    border-radius: 6px;
    transition: all 0.3s ease;
}

.nav-links a:hover, .dropdown:hover > a {
    background-color: #E6F0FF;
    color: var(--brand-blue);
}

/* Dropdown Menu */
.dropdown {
    position: relative;
}
.dropdown > a {
    display: flex;
    align-items: center;
    gap: 5px;
}
.dropdown .fa-chevron-down {
    font-size: 0.7em;
    transition: transform 0.3s ease;
}
.dropdown:hover .fa-chevron-down {
    transform: rotate(180deg);
}
.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--bg-light);
    list-style: none;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    min-width: 280px;
    opacity: 0;
    transform-origin: top center;
    animation: dropdown-fade-in 0.3s ease-out forwards;
    margin: 0;
}
@keyframes dropdown-fade-in {
    from { opacity: 0; transform: translateX(-50%) translateY(10px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}
.dropdown:hover .dropdown-menu {
    display: block;
}
.dropdown-menu li a {
    padding: 12px 20px;
    display: block;
    white-space: nowrap;
    color: var(--text-primary);
    border-radius: 6px;
}
.dropdown-menu li a:hover {
    background-color: #E6F0FF;
    color: var(--brand-blue);
}
.nav-actions {
    display: flex;
}

/* START: Mobile Menu Styles */
#mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
}
#mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2000;
    visibility: hidden;
    transition: visibility 0.3s;
}
#mobile-menu.open {
    visibility: visible;
}
.mobile-menu-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    opacity: 0;
    transition: opacity 0.3s ease;
}
#mobile-menu.open .mobile-menu-overlay {
    opacity: 1;
}
.mobile-menu-panel {
    position: absolute;
    top: 0;
    right: 0;
    width: 85%;
    max-width: 320px;
    height: 100%;
    background-color: var(--bg-light);
    transform: translateX(100%);
    transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    display: flex;
    flex-direction: column;
    padding: 20px;
}
#mobile-menu.open .mobile-menu-panel {
    transform: translateX(0);
}
.mobile-menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}
.mobile-menu-header img {
    height: 35px;
}
#mobile-menu-close-btn {
    font-size: 1.5rem;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
}
.mobile-nav-links {
    list-style: none;
    padding-top: 20px;
}
.mobile-nav-links li {
    border-bottom: 1px solid var(--border-color);
}
.mobile-nav-links li:last-child {
    border-bottom: none;
}
.mobile-nav-links a {
    display: block;
    padding: 15px 0;
    color: var(--text-primary);
    font-weight: 600;
}
.mobile-nav-links .mobile-submenu {
    list-style: none;
    padding-left: 20px;
}
.mobile-nav-links .mobile-submenu a {
    font-weight: 400;
    color: var(--text-secondary);
    padding: 10px 0;
}
.mobile-menu-actions {
    margin-top: auto;
    padding-top: 20px;
}
.mobile-menu-actions .btn {
    width: 100%;
}
/* END: Mobile Menu Styles */

/* Responsive Design */
@media (max-width: 1024px) {
    .nav-desktop { display: none; }
    #mobile-menu-btn { display: block; }
}

@media (max-width: 768px) {
    h1 { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
}