/* =========================================
   1. KHAI BÁO BIẾN MÀU SẮC (COLOR SYSTEM)
========================================= */
:root {
    /* Primary Colors (Màu chủ đạo) */
    --primary-bg: #0F0F0F;       /* Đen Vực Thẳm - Nền chính */
    --primary-dark: #1A1A1A;     /* Đen Nhạt - Nền menu */
    --primary-gold: #D4AF37;     /* Vàng Vinh Quang - Text nhấn, viền, icon */
    
    /* Accent Colors (Màu điểm nhấn đối kháng) */
    --accent-red: #C41E3A;       /* Đỏ Nhiệt Huyết */
    --accent-blue: #0047AB;      /* Xanh Trí Tuệ */
    
    /* Neutral Colors (Màu trung tính) */
    --text-light: #FFFFFF;
    --text-muted: #CCCCCC;

    /* HỆ THỐNG PHÔNG CHỮ (TYPOGRAPHY SYSTEM) */
    --font-headline: 'Russo One', sans-serif;
    --font-subhead: 'Anton', sans-serif;
    --font-body: 'Montserrat', sans-serif;
}

/* =========================================
   2. RESET CSS & TYPOGRAPHY
========================================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: var(--font-body); /* Đã đổi thành biến CSS */
}

body {
    background-color: var(--primary-bg);
    color: var(--text-light);
    overflow-x: hidden; /* Tránh thanh cuộn ngang rác giao diện */
}

/* =========================================
   3. THANH ĐIỀU HƯỚNG (NAVBAR)
========================================= */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 50px;
    background-color: rgba(15, 15, 15, 0.95);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 2px solid var(--primary-gold);
    transition: transform 0.3s ease-in-out, background-color 0.3s ease-in-out, backdrop-filter 0.3s ease-in-out;
}

.navbar.navbar--hidden {
    transform: translateY(-100%);
}

.navbar.navbar--transparent {
    background-color: rgba(15, 15, 15, 0.6); 
    backdrop-filter: blur(12px); 
    -webkit-backdrop-filter: blur(12px); 
    transform: translateY(0); 
}

.navbar.navbar--solid {
    background-color: rgba(15, 15, 15, 0.95);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    transform: translateY(0);
}

.logo a {
    display: flex; 
    align-items: center;
    text-decoration: none; 
}

.logo img {
    max-height: 55px; 
    width: auto; 
    display: block; 
    transition: transform 0.3s ease; 
}

.logo img:hover {
    transform: scale(1.05); 
}

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin: 0 15px;
    position: relative;
}

.nav-links a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 700;
    font-size: 14px;
    text-transform: uppercase;
    transition: color 0.3s ease;
    font-family: var(--font-body); 
    letter-spacing: 1.5px;
}

.nav-links a:hover {
    color: var(--primary-gold);
}

/* --- MENU CẤP 1 --- */
.dropdown-menu {
    display: block; 
    visibility: hidden; 
    opacity: 0;         
    transform: translateY(15px); 
    transition: visibility 0.3s, opacity 0.3s ease, transform 0.3s ease; 
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--primary-dark);
    list-style: none;
    min-width: 250px; 
    border-top: 3px solid var(--primary-gold);
    padding: 10px 0;
    font-family: var(--font-body) !important; 
    letter-spacing: 1.5px;
}

.dropdown-menu a {
    padding: 10px 20px;
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    white-space: nowrap; 
    text-transform: none; 
    font-family: var(--font-body) !important; 
    letter-spacing: 1.5px;
}

.dropdown-menu a .arrow {
    font-size: 18px; 
    transition: transform 0.3s ease; 
}

.sub-dropdown:hover > a .arrow {
    transform: rotate(90deg);
}

.dropdown:hover .dropdown-menu {
    visibility: visible;
    opacity: 1;           
    transform: translateY(0); 
}

.dropdown-menu a:hover {
    background-color: #333333;
}

/* --- MENU CẤP 2 (NESTED DROPDOWN) --- */
.dropdown-menu li {
    position: relative; 
    margin: 0;
}

.sub-dropdown-menu {
    display: block; 
    visibility: hidden;
    opacity: 0;
    transform: translateX(15px); 
    transition: visibility 0.3s, opacity 0.3s ease, transform 0.3s ease;
    position: absolute;
    top: 0;
    left: auto;  
    right: 100%; 
    background-color: var(--primary-dark);
    list-style: none;
    min-width: 180px;
    border-left: none; 
    border-right: 2px solid var(--primary-gold);
    padding: 10px 0;
    box-shadow: -5px 2px 10px rgba(0, 0, 0, 0.5); 
    font-family: var(--font-body) ; 
    letter-spacing: 1.5px;
}

.sub-dropdown-menu a {
    padding: 10px 20px;
    display: block;
    text-transform: none; 
    font-size: 13px; 
}

.sub-dropdown-menu a:hover {
    background-color: #333333;
    color: var(--primary-gold);
}

.sub-dropdown:hover .sub-dropdown-menu {
    visibility: visible;
    opacity: 1;
    transform: translateX(0); 
}

/* =========================================
   4. KÝ HIỆU MENU ĐIỆN THOẠI (BURGER)
========================================= */
.burger {
    display: none;
    cursor: pointer;
}

.burger div {
    width: 25px;
    height: 3px;
    background-color: var(--primary-gold);
    margin: 5px;
    transition: all 0.3s ease;
}

/* =========================================
   7. RESPONSIVE GIAO DIỆN ĐIỆN THOẠI
========================================= */
@media screen and (max-width: 768px) {
    .burger { display: block; }

    .nav-links {
        position: absolute;
        right: 0;
        top: 65px; 
        height: 100vh;
        width: 100%;
        background-color: rgba(15, 15, 15, 0.98);
        display: flex;
        flex-direction: column;
        align-items: center;
        padding-top: 30px;
        transform: translateX(100%); 
        transition: transform 0.4s ease-in;
    }

    .nav-links.nav-active {
        transform: translateX(0%);
    }

    .nav-links li {
        margin: 15px 0;
        width: 100%;
        text-align: center;
    }

    .dropdown-menu, 
    .sub-dropdown-menu {
        position: static;
        min-width: 100%;
        background-color: transparent;
        border: none;
        box-shadow: none;
        padding: 0;
    }

    .dropdown-menu a, 
    .sub-dropdown-menu a {
        justify-content: center; 
        padding: 10px;
        font-size: 14px;
        color: #CCCCCC; 
    }

    .dropdown:hover .dropdown-menu,
    .sub-dropdown:hover .sub-dropdown-menu {
        display: block;
    }

    .toggle .line1 { transform: rotate(-45deg) translate(-5px, 6px); }
    .toggle .line2 { opacity: 0; }
    .toggle .line3 { transform: rotate(45deg) translate(-5px, -6px); }
}

/* =========================================
   8. SECTION 4: LỘ TRÌNH (TIMELINE)
========================================= */
.container {
    max-width: 1200px;
    margin: 0 auto;
}

.text-center {
    text-align: center;
}

.section-heading .section-title {
    padding-top: 100px;
    font-family: var(--font-headline);
    font-size: 2.5rem;
    color: var(--primary-gold);
    margin-bottom: 10px; 
    letter-spacing: 2px;
}

.section-subtitle {
    color: #999;
    font-size: 1.1rem;
    max-width: 700px;
    margin: 15px auto 50px; 
    line-height: 1.6;
}
.info-timeline-section {
    padding: 100px 20px;
    background-color: var(--primary-bg);
}

.timeline-container {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    padding: 40px 0;
}

.timeline-container::after {
    content: '';
    position: absolute;
    width: 4px;
    background: linear-gradient(to bottom, var(--accent-red), var(--primary-gold));
    top: 0;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
    box-shadow: 0 0 15px rgba(212, 175, 55, 0.5);
}

.timeline-item {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%; 
    box-sizing: border-box;
    margin-bottom: 40px;
}

.timeline-item.left { left: 0; }
.timeline-item.right { left: 50%; }

.timeline-dot {
    position: absolute;
    width: 50px;
    height: 50px;
    right: -25px; 
    background-color: #111;
    border: 4px solid var(--primary-gold);
    top: 15px;
    border-radius: 50%;
    z-index: 10;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-light);
    font-size: 1.2rem;
    box-shadow: 0 0 20px rgba(212, 175, 55, 0.4);
}

.timeline-item.right .timeline-dot {
    left: -25px;
}

.timeline-content {
    padding: 30px;
    background-color: #111;
    position: relative;
    border-radius: 10px;
    border: 1px solid #333;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.timeline-item:hover .timeline-content {
    transform: translateY(-5px);
    border-color: var(--primary-gold);
    box-shadow: 0 10px 25px rgba(0,0,0,0.5);
}

.timeline-date {
    display: inline-block;
    padding: 5px 15px;
    background-color: rgba(212, 175, 55, 0.1);
    color: var(--primary-gold);
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 700;
    margin-bottom: 15px;
    border: 1px solid var(--primary-gold);
}

.timeline-content h3 {
    font-size: 1.5rem;
    color: #FFF;
    margin-bottom: 10px;
    font-family: var(--font-subhead);
}

.timeline-content p {
    color: #AAA;
    line-height: 1.6;
    font-size: 0.95rem;
}

@media screen and (max-width: 768px) {
    .timeline-container::after { left: 31px; }
    .timeline-item { width: 100%; padding-left: 80px; padding-right: 20px; }
    .timeline-item.right { left: 0; }
    .timeline-item.left .timeline-dot, .timeline-item.right .timeline-dot { left: 6px; }
}

/* =========================================
   LỊCH TRÌNH SỰ KIỆN (VERTICAL TIMELINE)
========================================= */
.timeline-section {
    padding: 80px 20px;
    background-color: #0a0a0a;
}

.timeline-container {
    position: relative;
    max-width: 900px;
    margin: 50px auto 0;
    padding: 20px 0;
}

/* Đường kẻ dọc ở giữa */
.timeline-container::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: #333;
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
    border-radius: 2px;
}

.timeline-item {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
    box-sizing: border-box;
}

/* Thẻ nằm bên trái */
.timeline-item:nth-child(odd) {
    left: 0;
    text-align: right;
}

/* Thẻ nằm bên phải */
.timeline-item:nth-child(even) {
    left: 50%;
    text-align: left;
}

/* Dấu chấm phát sáng trên trục thời gian */
.timeline-dot {
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: var(--primary-bg);
    border: 4px solid var(--primary-gold);
    top: 25px;
    border-radius: 50%;
    z-index: 1;
    transition: all 0.3s ease;
}

.timeline-item:nth-child(even) .timeline-dot {
    left: -10px;
}

.timeline-item:hover .timeline-dot {
    background-color: var(--primary-gold);
    box-shadow: 0 0 15px var(--primary-gold);
}

/* Nội dung trong Timeline */
.timeline-content {
    padding: 20px 30px;
    background-color: #111;
    border: 1px solid #333;
    position: relative;
    border-radius: 8px;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.timeline-item:hover .timeline-content {
    transform: translateY(-5px);
    border-color: #555;
}

.timeline-date {
    display: inline-block;
    color: #00A3E0;
    font-weight: 700;
    font-size: 0.95rem;
    margin-bottom: 10px;
    letter-spacing: 1px;
    background-color: rgba(0, 163, 224, 0.1);
    padding: 5px 12px;
    border-radius: 20px;
}

.timeline-phase {
    color: #FFF;
    font-family: var(--font-headline);
    font-size: 1.5rem;
    margin-bottom: 10px;
}

.timeline-content p {
    color: #888;
    line-height: 1.6;
    margin: 0;
    font-size: 0.95rem;
}

/* Style riêng cho các thẻ đặc biệt (Tứ Kết, Chung Kết) */
.highlight-item .timeline-content { border-color: var(--primary-gold); box-shadow: 0 0 20px rgba(212, 175, 55, 0.1); }
.pulse-dot { animation: pulse-gold 2s infinite; }

.final-item .timeline-content { border-color: var(--accent-red); background: linear-gradient(135deg, rgba(196, 30, 58, 0.1) 0%, #111 100%); }
.trophy-dot { 
    width: 40px; height: 40px; right: -20px; top: 15px; 
    background-color: var(--accent-red); border-color: var(--accent-red); color: #FFF;
    display: flex; justify-content: center; align-items: center; font-size: 1.2rem;
}

@keyframes pulse-gold {
    0% { box-shadow: 0 0 0 0 rgba(212, 175, 55, 0.7); }
    70% { box-shadow: 0 0 0 10px rgba(212, 175, 55, 0); }
    100% { box-shadow: 0 0 0 0 rgba(212, 175, 55, 0); }
}

/* --- Responsive cho Điện thoại (Ép Timeline về 1 bên) --- */
@media screen and (max-width: 768px) {
    .timeline-container::after { left: 31px; }
    .timeline-item { width: 100%; padding-left: 70px; padding-right: 0; text-align: left !important; }
    .timeline-item:nth-child(even) { left: 0; }
    .timeline-dot { left: 21px !important; right: auto; }
    .trophy-dot { left: 11px !important; }
}

/* =========================================
   9. FOOTER (CHÂN TRANG)
========================================= */
.site-footer {
    background-color: #050505; 
    border-top: 3px solid var(--primary-gold);
    color: var(--text-muted);
    padding: 60px 50px 20px;
    font-family: var(--font-body);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1.5fr 1fr; 
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h3 {
    font-family: var(--font-subhead);
    color: var(--text-light);
    font-size: 1.2rem;
    margin-bottom: 20px;
    letter-spacing: 1px;
}

.footer-logo { max-height: 60px; margin-bottom: 15px; }
.brand-col p { line-height: 1.6; font-size: 0.95rem; }

.link-col ul { list-style: none; }
.link-col li { margin-bottom: 12px; }
.link-col a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.3s ease, padding-left 0.3s ease;
}
.link-col a:hover {
    color: var(--primary-gold);
    padding-left: 8px; 
}

.contact-col p {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.contact-col i { color: var(--primary-gold); } 

.social-links { display: flex; gap: 15px; }
.social-icon {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 45px;
    height: 45px;
    background-color: var(--primary-dark);
    color: var(--text-light);
    border-radius: 50%; 
    text-decoration: none;
    font-size: 1.2rem;
    transition: all 0.3s ease;
    border: 1px solid #333;
}

.social-icon.facebook:hover { background-color: #1877F2; border-color: #1877F2; transform: translateY(-5px); }
.social-icon.youtube:hover { background-color: #FF0000; border-color: #FF0000; transform: translateY(-5px); }
.social-icon.tiktok:hover { background-color: #000000; border-color: #25F4EE; color: #25F4EE; transform: translateY(-5px); }

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #222;
    font-size: 0.85rem;
}

@media screen and (max-width: 992px) { .footer-container { grid-template-columns: 1fr 1fr; } }
@media screen and (max-width: 576px) {
    .footer-container { grid-template-columns: 1fr; text-align: center; } 
    .contact-col p, .social-links { justify-content: center; }
}

/* =========================================
   10. THỜI GIAN & NÚT BẤM (CẬP NHẬT MỚI)
========================================= */
.timeline-time {
    font-family: var(--font-body);
    font-size: 1.1rem;
    color: #FFF;
    font-weight: 600;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.timeline-time i {
    color: var(--primary-gold);
}

.timeline-btn {
    display: inline-block;
    margin-top: 20px;
    padding: 10px 25px;
    font-size: 0.95rem;
    font-weight: 700;
    text-decoration: none;
    border-radius: 5px;
    background-color: var(--primary-gold);
    color: var(--primary-bg); /* Chữ tối màu trên nền vàng */
    transition: all 0.3s ease;
    text-transform: uppercase;
}

.timeline-btn:hover {
    background-color: #FFF;
    color: var(--primary-bg);
    box-shadow: 0 0 15px rgba(212, 175, 55, 0.6);
}

/* Biến thể: Nút Viền (Outline) cho Livestream */
.timeline-btn.outline-btn {
    background-color: transparent;
    border: 2px solid var(--accent-red);
    color: var(--accent-red);
}

.timeline-btn.outline-btn:hover {
    background-color: var(--accent-red);
    color: #FFF;
    box-shadow: 0 0 15px rgba(229, 9, 20, 0.5);
}