/* ============================================================
   assets/css/style.css — Giao diện chuẩn hoá đa nền tảng (Mobile & PC)
   Học tập chính trị & Thi trắc nghiệm trực tuyến
   ============================================================ */

/* --- 1. CẤU HÌNH BIẾN MÀU SẮC & THEME --- */
:root {
    /* Màu chủ đạo: đọc từ PHP ($mau_chu_dao), mặc định đỏ cờ */
    --primary-color: #b30000;
    --primary: var(--primary-color, #b30000);
    --primary-hover: #8f0000;
    --primary-light: #fbebee;
    
    /* Màu điểm nhấn & Quân đội */
    --gold: #d4af37;
    --gold-light: #fff9e6;
    --army-green: #3d4d23;
    --army-green-light: #eef3e6;
    
    /* Màu chữ & Nền */
    --text-main: #1f1f1f;
    --text-muted: #666666;
    --bg-body: #f4f1ea;
    --card-bg: #ffffff;
    --border-color: #e2e6ea;
    
    /* Trạng thái */
    --success: #198754;
    --success-bg: #e8f5e9;
    --danger: #dc3545;
    --danger-bg: #ffebee;
    --warning: #ffc107;
    --warning-bg: #fff8e1;
    --info: #0d6efd;
    --info-bg: #e3f2fd;
    
    /* Kích thước & Hiệu ứng */
    --radius-sm: 6px;
    --radius: 10px;
    --radius-lg: 16px;
    --shadow-sm: 0 2px 6px rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.12);
    --transition: 0.2s ease;
}

/* --- 2. RESET & BASE TYPOGRAPHY --- */
*, *::before, *::after {
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-body);
    background-image: radial-gradient(rgba(179, 0, 0, 0.04) 1px, transparent 1px);
    background-size: 20px 20px;
    color: var(--text-main);
    margin: 0;
    padding: 0;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Chừa khoảng trống dưới đáy trên di động cho thanh Bottom Nav */
@media (max-width: 768px) {
    body.has-bottom-nav {
        padding-bottom: 75px;
    }
}

img {
    max-width: 100%;
    height: auto;
    display: inline-block;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-hover);
}

/* --- 3. LAYOUT (APP SHELL & CARDS) --- */
.app-shell {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 20px 14px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    border-top: 4px solid var(--primary);
    padding: 24px 20px;
    margin-bottom: 20px;
    position: relative;
    transition: var(--transition);
}

.card h2, .card-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    margin: 0 0 16px 0;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-light);
    display: flex;
    align-items: center;
    gap: 8px;
}

/* --- 4. HEADER CHUNG (THỐNG NHẤT TOÀN BỘ TRANG) --- */
.header-bar, .app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--gold);
    margin-bottom: 18px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 14px;
    flex: 1;
    min-width: 220px;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.app-logo-img {
    width: 60px;
    height: 60px;
    object-fit: contain;
    border-radius: 50%;
    background: #ffffff;
    padding: 4px;
    border: 2px solid var(--gold);
    box-shadow: var(--shadow-sm);
    flex-shrink: 0;
}

.app-title {
    margin: 0;
    color: var(--primary);
    font-weight: 800;
    font-size: 1.35rem;
    line-height: 1.25;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.app-subtitle {
    margin: 3px 0 0 0;
    font-size: 0.9rem;
    color: var(--text-muted);
}

.user-info {
    font-size: 0.9rem;
    color: var(--text-muted);
}
.user-info strong {
    color: var(--primary);
}

/* --- 5. HỆ THỐNG MENU ĐIỀU HƯỚNG (DESKTOP & MOBILE) --- */
.menu-user-wrap {
    margin-bottom: 20px;
}

/* Menu ngang trên Desktop */
.menu-links {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    background: #ffffff;
    padding: 6px;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.menu-links a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--text-main);
    text-decoration: none;
    font-weight: 600;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    transition: var(--transition);
}

.menu-links a:hover {
    background: var(--primary-light);
    color: var(--primary);
}

.menu-links a.active {
    background: var(--primary);
    color: #ffffff;
    box-shadow: 0 2px 8px rgba(179, 0, 0, 0.25);
}

/* Drawer / Hamburger mobile */
.hamburger-btn {
    display: none;
    background: var(--primary);
    color: #ffffff;
    border: none;
    border-radius: var(--radius-sm);
    width: 42px;
    height: 42px;
    font-size: 1.3rem;
    cursor: pointer;
    align-items: center;
    justify-content: center;
}

.mobile-menu {
    display: none;
    flex-direction: column;
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 8px;
    margin-bottom: 16px;
    gap: 4px;
    box-shadow: var(--shadow);
}

.mobile-menu a {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-main);
    font-weight: 600;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
}

.mobile-menu a:hover,
.mobile-menu a.active {
    background: var(--primary);
    color: #ffffff;
}

/* Thanh điều hướng cố định dưới đáy Mobile (Bottom Navigation Bar) */
.mobile-bottom-nav {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 62px;
    background: #ffffff;
    border-top: 1px solid var(--border-color);
    box-shadow: 0 -3px 12px rgba(0, 0, 0, 0.08);
    z-index: 999;
    justify-content: space-around;
    align-items: center;
    padding: 0 4px;
}

.bottom-nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    text-decoration: none;
    padding: 6px 0;
    font-size: 0.72rem;
    font-weight: 600;
    transition: var(--transition);
}

.bottom-nav-icon {
    font-size: 1.25rem;
    line-height: 1;
    margin-bottom: 2px;
}

.bottom-nav-item.active {
    color: var(--primary);
}

.bottom-nav-item.active .bottom-nav-icon {
    transform: scale(1.15);
}

/* Responsive Menu */
@media (max-width: 768px) {
    .menu-links { display: none; }
    .mobile-bottom-nav { display: flex; }
}

/* --- 6. HỆ THỐNG NÚT BẤM (BUTTONS) --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-weight: 700;
    font-size: 0.95rem;
    text-decoration: none;
    text-align: center;
    cursor: pointer;
    border: none;
    transition: var(--transition);
    user-select: none;
}

.btn:active {
    transform: scale(0.98);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    color: #ffffff;
    box-shadow: 0 3px 8px rgba(179, 0, 0, 0.2);
}

.btn-primary:hover {
    background: var(--primary-hover);
    color: #ffffff;
    box-shadow: 0 5px 14px rgba(179, 0, 0, 0.3);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--army-green);
    color: var(--army-green);
}

.btn-outline:hover {
    background: var(--army-green);
    color: #ffffff;
}

.btn-danger {
    background: #ffffff;
    color: var(--danger);
    border: 1.5px solid var(--danger);
}

.btn-danger:hover {
    background: var(--danger);
    color: #ffffff;
}

.btn-success {
    background: var(--success);
    color: #ffffff;
}

.btn-success:hover {
    background: #146c43;
    color: #ffffff;
}

/* Nút cài đặt PWA */
.btn-install-app {
    background: linear-gradient(135deg, #1e7e34, #155724);
    color: #ffffff;
    border: none;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-weight: 700;
    font-size: 0.88rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    box-shadow: 0 2px 8px rgba(30, 126, 52, 0.25);
    transition: var(--transition);
}

.btn-install-app:hover {
    background: #155724;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(30, 126, 52, 0.35);
}

.btn-install-app.is-installed {
    background: #6c757d;
    cursor: default;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.82rem;
    border-radius: 4px;
}

.btn-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.btn-row > * {
    flex: 1;
    min-width: 130px;
}

/* --- 7. FORM & INPUTS --- */
.form-group {
    margin-bottom: 18px;
}

label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
    color: var(--army-green);
    font-size: 0.95rem;
}

.input, select.input {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: inherit;
    background: #ffffff;
    color: var(--text-main);
    transition: var(--transition);
}

.input:focus {
    border-color: var(--primary);
    outline: none;
    box-shadow: 0 0 0 3px rgba(179, 0, 0, 0.12);
}

/* --- 8. GIAO DIỆN LÀM BÀI TRẮC NGHIỆM (THI & THI THỬ) --- */
.exam-top-bar {
    background: var(--bg-body);
    padding: 14px 18px;
    border-radius: var(--radius);
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: bold;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.countdown {
    color: var(--primary);
    font-size: 1.4rem;
    font-weight: 900;
    font-family: monospace;
    background: #ffffff;
    padding: 4px 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--primary-light);
}

.question-body {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: #111111;
    line-height: 1.5;
    background: #fafaf8;
    padding: 16px;
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--primary);
}

.answers-list {
    list-style: none;
    padding: 0;
    margin: 0 0 24px 0;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.answer-option {
    display: flex;
    align-items: flex-start;
    padding: 14px 16px;
    border: 2px solid #e2e6ea;
    border-radius: var(--radius);
    cursor: pointer;
    background: #ffffff;
    transition: var(--transition);
    min-height: 52px;
}

.answer-option:hover {
    background: #fffdf5;
    border-color: var(--gold);
}

.answer-option.selected {
    background: var(--gold-light);
    border-color: var(--primary);
    box-shadow: 0 3px 10px rgba(179, 0, 0, 0.08);
}

.answer-option input[type="radio"] {
    margin-top: 3px;
    margin-right: 12px;
    accent-color: var(--primary);
    transform: scale(1.3);
    flex-shrink: 0;
}

.answer-label {
    font-weight: 800;
    margin-right: 6px;
    color: var(--primary);
}

/* Thanh điều hướng câu hỏi vuốt ngang */
.question-nav-wrapper {
    margin-top: 30px;
    padding-top: 18px;
    border-top: 1px dashed #ddd;
}

.question-nav-title {
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--army-green);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.question-nav {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding: 4px 2px 10px 2px;
    scrollbar-width: thin;
    -webkit-overflow-scrolling: touch;
}

.question-nav::-webkit-scrollbar {
    height: 6px;
}

.question-nav::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 10px;
}

.q-nav-item {
    flex-shrink: 0;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1.5px solid #d0d7de;
    border-radius: var(--radius-sm);
    font-size: 0.92rem;
    cursor: pointer;
    background: #ffffff;
    font-weight: 700;
    transition: var(--transition);
}

.q-nav-item.current {
    border-color: var(--primary);
    background: var(--primary);
    color: #ffffff;
    transform: scale(1.08);
    box-shadow: 0 3px 8px rgba(179, 0, 0, 0.3);
}

.q-nav-item.answered {
    background: var(--gold-light);
    border-color: var(--gold);
    color: var(--text-main);
}

/* --- 9. BẢNG DỮ LIỆU & RESPONSIVE TABLES --- */
.table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin-bottom: 16px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
}

.table {
    width: 100%;
    border-collapse: collapse;
    min-width: 500px;
    background: #ffffff;
}

.table th, .table td {
    padding: 12px 14px;
    border-bottom: 1px solid #f0f0f0;
    text-align: left;
    font-size: 0.92rem;
}

.table th {
    background: #f8f9fa;
    color: var(--army-green);
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.8rem;
    letter-spacing: 0.5px;
}

.table tr:hover {
    background: #fffef7;
}

/* --- 10. THÔNG BÁO, BADGES & STATS --- */
.alert {
    padding: 14px 16px;
    border-radius: var(--radius-sm);
    margin-bottom: 18px;
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.alert-info { background: var(--info-bg); color: #084298; border-left: 4px solid var(--info); }
.alert-success { background: var(--success-bg); color: #0f5132; border-left: 4px solid var(--success); }
.alert-danger { background: var(--danger-bg); color: #842029; border-left: 4px solid var(--danger); }

.badge-status {
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    color: #ffffff;
    white-space: nowrap;
    display: inline-block;
}

.status-open { background: var(--success); }
.status-upcoming { background: var(--warning); color: #000; }
.status-ended { background: var(--danger); }
.status-paused { background: #6c757d; }

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 12px;
    background: #fafaf8;
    padding: 16px;
    border-radius: var(--radius);
    border: 1px dashed #d0d7de;
    margin-bottom: 18px;
}

.info-item-label {
    font-size: 0.78rem;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 2px;
}

.info-item-value {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-main);
}

/* --- 11. CHÂN TRANG (FOOTER) --- */
.footer, .home-footer {
    text-align: center;
    margin-top: 30px;
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* --- 12. PWA INSTALL MODAL (HỘP THOẠI HƯỚNG DẪN CÀI ĐẶT) --- */
.pwa-modal-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.6);
    z-index: 10000;
    align-items: center;
    justify-content: center;
    padding: 16px;
    backdrop-filter: blur(3px);
}

.pwa-modal-overlay.open {
    display: flex;
}

.pwa-modal-card {
    background: #ffffff;
    width: 100%;
    max-width: 480px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: pwaSlideUp 0.25s ease-out;
}

@keyframes pwaSlideUp {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.pwa-modal-header {
    background: linear-gradient(135deg, var(--primary), #800000);
    color: #ffffff;
    padding: 16px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.pwa-modal-title {
    font-size: 1.15rem;
    font-weight: 800;
    color: #ffffff;
}

.pwa-modal-close {
    background: transparent;
    border: none;
    color: #ffffff;
    font-size: 1.3rem;
    cursor: pointer;
    padding: 0;
    line-height: 1;
}

.pwa-modal-body {
    padding: 20px;
}

.pwa-modal-lead {
    font-size: 0.92rem;
    color: var(--text-muted);
    margin: 0 0 16px 0;
}

.pwa-tabs {
    display: flex;
    gap: 6px;
    border-bottom: 2px solid #eee;
    margin-bottom: 16px;
}

.pwa-tab-btn {
    flex: 1;
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    padding: 8px 4px;
    font-weight: 700;
    font-size: 0.85rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: var(--transition);
}

.pwa-tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.pwa-tab-pane {
    display: none;
}

.pwa-tab-pane.active {
    display: block;
}

.pwa-step {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 12px;
    font-size: 0.92rem;
    line-height: 1.45;
}

.pwa-step-num {
    background: var(--primary-light);
    color: var(--primary);
    font-weight: 800;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    flex-shrink: 0;
    margin-top: 1px;
}

.pwa-modal-footer {
    padding: 12px 20px 20px 20px;
    background: #fafafa;
    border-top: 1px solid #eee;
}

/* --- 13. RESPONSIVE TWEAKS FOR PHONES (< 768px) --- */
@media (max-width: 768px) {
    .app-shell { padding: 12px 8px; }
    .card { padding: 18px 14px; border-radius: var(--radius-sm); }
    .app-title { font-size: 1.15rem; }
    .app-subtitle { font-size: 0.82rem; }
    .app-logo-img { width: 48px; height: 48px; }
    .btn-row { flex-direction: column; }
    .btn-row > * { width: 100%; }
    .exam-top-bar { flex-direction: column; gap: 8px; text-align: center; }
    .info-grid { grid-template-columns: 1fr; }
    .q-nav-item { width: 40px; height: 40px; }
}
/* ---------- Đăng nhập / Đăng ký: nền riêng cho mobile ---------- */
@media (max-width: 768px) {
    .login-page,
    .reg-page {
        background-image: url('../images/login_mobile.png') !important;
        background-size: cover;
        background-position: center;
        background-repeat: no-repeat;
    }
}