/**
 * KBBETVN.NET - Premium Design System
 * Mobile-First, Vibrant, Modern, Premium
 * Typography: Be Vietnam Pro (Headings & Body)
 * Color Scheme: Purple/Violet Primary, Gradient Backgrounds
 */

/* ========================================
   CSS Variables - Premium Design System
======================================== */
:root {
    /* Primary Colors - Fresh Green palette */
    --color-primary: #16A34A;
    --color-primary-dark: #15803D;
    --color-primary-light: #D1FADF;
    --color-primary-hover: #22C55E;
    --color-primary-gradient: linear-gradient(135deg, #16A34A 0%, #22C55E 50%, #0EA5E9 100%);
    
    /* Secondary Colors - Deep Navy for contrast */
    --color-secondary: #0F172A;
    --color-secondary-dark: #0B1221;
    --color-secondary-light: #E2E8F0;
    --color-secondary-gradient: linear-gradient(135deg, #0F172A 0%, #1E293B 100%);
    
    /* Accent Colors - Amber for highlights */
    --color-accent: #F59E0B;
    --color-accent-dark: #D97706;
    --color-accent-light: #FEF3C7;
    --color-accent-gradient: linear-gradient(135deg, #F59E0B 0%, #FBBF24 100%);
    
    /* Background Colors - Clean & light */
    --color-bg: #F6F8F9;
    --color-bg-alt: #ECF4EE;
    --color-bg-section: #E4EFE7;
    --color-bg-dark: #0A0F1F; /* Footer only */
    --color-bg-gradient: linear-gradient(135deg, #0F172A 0%, #0B2E26 50%, #0EA5E9 100%);
    
    /* Surface Colors */
    --color-surface: #FFFFFF;
    --color-surface-elevated: #F9FEFB;
    --color-surface-hover: #F3F8F4;
    
    /* Text Colors */
    --color-text: #0F172A;
    --color-text-secondary: #334155;
    --color-text-muted: #94A3B8;
    --color-text-inverse: #FFFFFF;
    --color-text-link: #15803D;
    
    /* Border & Divider */
    --color-border: #E2E8F0;
    --color-border-light: #F1F5F9;
    --color-divider: #CBD5E1;
    
    /* Shadows - softer neutral */
    --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.04);
    --shadow-sm: 0 1px 3px 0 rgba(15, 23, 42, 0.08), 0 1px 2px 0 rgba(15, 23, 42, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -1px rgba(15, 23, 42, 0.04);
    --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.10), 0 4px 6px -2px rgba(15, 23, 42, 0.06);
    --shadow-xl: 0 20px 25px -5px rgba(15, 23, 42, 0.12), 0 10px 10px -5px rgba(15, 23, 42, 0.06);
    --shadow-2xl: 0 25px 50px -12px rgba(22, 163, 74, 0.22);
    
    /* Typography - Inter (tối ưu tiếng Việt) */
    --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* Font Sizes */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;
    
    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-2xl: 2rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Container */
    --container-max: 1280px;
    --container-narrow: 900px;
    --container-padding: 1rem;

    /* App bar height (used for sticky offset) */
    --appbar-h: 48px;
}

/* ========================================
   Reset & Base
======================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-weight: 400;
    font-size: var(--text-base);
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

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

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

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

ul, ol {
    list-style: none;
}

/* ========================================
   Typography
======================================== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-text);
    margin-bottom: var(--space-4);
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 800;
}

h2 {
    font-size: clamp(1.75rem, 5vw, 2.75rem);
    font-weight: 700;
}

h3 {
    font-size: clamp(1.5rem, 4vw, 2rem);
    font-weight: 600;
}

h4 {
    font-size: var(--text-xl);
    font-weight: 600;
}

p {
    margin-bottom: var(--space-4);
    line-height: 1.8;
}

.lead {
    font-size: clamp(1.125rem, 2.5vw, 1.375rem);
    color: var(--color-text-secondary);
    font-weight: 300;
    line-height: 1.7;
}

/* ========================================
   Container
======================================== */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.container-narrow {
    max-width: var(--container-narrow);
}

/* ========================================
   Buttons - Premium Style
======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 1rem 2rem;
    min-height: 52px;
    font-family: var(--font-heading);
    font-size: var(--text-base);
    font-weight: 600;
    line-height: 1.5;
    text-align: center;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: var(--color-primary-gradient);
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
    padding: calc(1rem - 2px) calc(2rem - 2px);
}

.btn-secondary:hover {
    background-color: var(--color-primary-light);
    border-color: var(--color-primary-dark);
}

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

.btn-outline:hover {
    background-color: var(--color-bg-alt);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

/* ========================================
   Cards - Premium Style
======================================== */
.card {
    background-color: var(--color-surface);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
    border-color: var(--color-primary-light);
}

.card-image {
    width: 100%;
    margin-bottom: var(--space-4);
    border-radius: var(--radius-lg);
    overflow: hidden;
    aspect-ratio: 16/9;
}

.card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.card:hover .card-image img {
    transform: scale(1.05);
}

.card-content {
    display: flex;
    flex-direction: column;
    flex: 1;
}

.card-title {
    font-family: var(--font-heading);
    font-size: var(--text-xl);
    font-weight: 600;
    margin-bottom: var(--space-3);
    color: var(--color-text);
}

.card-title a {
    color: var(--color-text);
}

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

.card-excerpt {
    color: var(--color-text-secondary);
    font-size: var(--text-sm);
    line-height: 1.7;
    margin-bottom: var(--space-4);
    flex: 1;
}

.card-meta {
    display: flex;
    gap: var(--space-4);
    font-size: var(--text-xs);
    color: var(--color-text-muted);
    margin-top: auto;
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border-light);
}

/* ========================================
   Grid System
======================================== */
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-6);
}

@media (min-width: 640px) {
    .card-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .card-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--space-8);
    }
}

/* ========================================
   App Bar (Top download bar)
======================================== */
.app-bar {
    position: sticky;
    top: 0;
    z-index: 120;
    height: var(--appbar-h);
    display: flex;
    align-items: center;
    background: rgba(15, 23, 42, 0.88);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.app-bar-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
}

.app-bar-info {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-width: 0;
}

.app-bar-badge {
    width: 28px;
    height: 28px;
    border-radius: var(--radius-full);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.14);
    color: #fff;
    font-size: 0.95rem;
    flex: 0 0 auto;
}

.app-bar-text {
    color: rgba(255, 255, 255, 0.92);
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 0.9rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.btn-app-download {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 36px;
    padding: 0 14px;
    border-radius: var(--radius-full);
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 0.9rem;
    color: #fff;
    background: var(--color-accent-gradient);
    box-shadow: 0 10px 22px rgba(249, 115, 22, 0.25);
    border: 1px solid rgba(255, 255, 255, 0.12);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    white-space: nowrap;
    flex: 0 0 auto;
}

.btn-app-download:hover {
    transform: translateY(-1px);
    box-shadow: 0 16px 30px rgba(249, 115, 22, 0.32);
}

@media (min-width: 1024px) {
    /* Ẩn app-bar ở desktop */
    :root { --appbar-h: 0px; }
    .app-bar { display: none; }
}

/* ========================================
   Header
======================================== */
.site-header {
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: var(--appbar-h);
    z-index: 100;
    box-shadow: var(--shadow-xs);
    backdrop-filter: blur(10px);
    background-color: rgba(255, 255, 255, 0.95);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4) 0;
    gap: var(--space-4);
    flex-wrap: nowrap;
}

.logo {
    display: flex;
    align-items: center;
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    font-weight: 800;
    color: var(--color-primary);
    text-decoration: none;
}

.logo-image {
    height: 44px;
    width: auto;
}

.main-nav {
    display: none;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: var(--space-8);
    list-style: none;
}

.nav-link {
    color: var(--color-text-secondary);
    font-family: var(--font-heading);
    font-weight: 500;
    font-size: var(--text-sm);
    padding: var(--space-2) 0;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-primary);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-primary-gradient);
    border-radius: var(--radius-full);
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

.header-search-toggle {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    height: 44px;
    padding: 0 12px;
    border-radius: var(--radius-full);
    border: 1px solid var(--color-border);
    background: rgba(255, 255, 255, 0.85);
    color: var(--color-text);
    font-family: var(--font-heading);
    font-weight: 700;
    cursor: pointer;
    box-shadow: var(--shadow-xs);
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
    white-space: nowrap;
}

.header-search-toggle:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    border-color: rgba(124, 58, 237, 0.25);
}

.search-icon { font-size: 1rem; }
.search-label { display: none; font-size: 0.92rem; }

@media (min-width: 640px) {
    .search-label { display: inline; }
}

/* Search overlay */
.search-overlay {
    position: fixed;
    inset: 0;
    z-index: 2000;
    display: grid;
    place-items: start center;
    padding: 16px;
}

/* Ẩn overlay khi có thuộc tính hidden (khắc phục hiển thị luôn) */
.search-overlay[hidden] {
    display: none !important;
}

.search-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    backdrop-filter: blur(6px);
}

.search-panel {
    position: relative;
    width: min(720px, 100%);
    margin-top: 10vh;
    border-radius: var(--radius-2xl);
    background: radial-gradient(circle at top left, rgba(124,58,237,0.08), transparent 60%), rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(124, 58, 237, 0.18);
    box-shadow: var(--shadow-2xl);
    padding: 18px 20px 16px;
}

.search-panel-form {
    margin-top: var(--space-3);
}

.search-panel-input-wrap {
    position: relative;
    display: flex;
    align-items: center;
    gap: 0;
    border-radius: 999px;
    background: #FFFFFF;
    border: 1px solid rgba(191, 219, 254, 0.9);
    box-shadow: 0 4px 15px rgba(148, 163, 184, 0.35);
    padding: 3px;
}

.search-panel-input {
    height: 52px;
    border-radius: 999px;
    border: none;
    padding: 0 18px;
    font-family: var(--font-body);
    font-size: 1rem;
    outline: none;
    flex: 1;
    background: transparent;
}

.search-panel-input:focus {
    box-shadow: none;
}

.search-panel-submit {
    position: static;
    height: 46px;
    padding: 0 24px;
    border-radius: 999px;
    font-size: 0.95rem;
    white-space: nowrap;
}

.search-panel-close {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 34px;
    height: 34px;
    border-radius: var(--radius-full);
    border: 1px solid rgba(124, 58, 237, 0.16);
    background: rgba(255, 255, 255, 0.9);
    cursor: pointer;
    font-weight: 900;
}

.search-panel-hints {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 12px;
}

.search-chip {
    display: inline-flex;
    align-items: center;
    height: 34px;
    padding: 0 12px;
    border-radius: var(--radius-full);
    background: rgba(124, 58, 237, 0.10);
    border: 1px solid rgba(124, 58, 237, 0.14);
    color: var(--color-primary-dark);
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 0.9rem;
}

.search-chip:hover {
    background: rgba(124, 58, 237, 0.14);
}

@media (max-width: 420px) {
    .header-search-toggle { height: 40px; padding: 0 10px; }
    .search-panel { margin-top: 8vh; }
    .search-panel-input-wrap {
        padding: 2px;
    }
    .search-panel-input {
        height: 46px;
    }
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.header-auth-btn {
    height: 44px;
    padding: 0 14px;
    min-height: 44px;
    border-radius: var(--radius-full);
    font-size: 0.95rem;
}

@media (max-width: 420px) {
    .header-auth-btn {
        height: 40px;
        padding: 0 10px;
        font-size: 0.9rem;
    }
}

/* Icon buttons: always visible on mobile (icon-only), labels show on larger screens */
.header-iconbtn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    height: 44px;
    padding: 0 var(--space-3);
    border-radius: var(--radius-full);
    border: 1px solid var(--color-border);
    background: rgba(255, 255, 255, 0.85);
    color: var(--color-text);
    box-shadow: var(--shadow-xs);
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.header-iconbtn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    border-color: rgba(124, 58, 237, 0.25);
}

.header-iconbtn .icon {
    font-size: 1.1rem;
    line-height: 1;
}

.header-iconbtn .label {
    display: none;
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 0.9rem;
}

.header-iconbtn-register {
    background: var(--color-primary-gradient);
    border-color: transparent;
    color: var(--color-text-inverse);
}

.header-iconbtn-register:hover {
    box-shadow: var(--shadow-lg);
}

.header-iconbtn-login {
    border-color: rgba(124, 58, 237, 0.22);
}

.header-iconbtn-app {
    border-color: rgba(20, 184, 166, 0.25);
}

@media (min-width: 480px) {
    .header-iconbtn .label {
        display: inline;
    }
}

@media (max-width: 420px) {
    .header-actions {
        gap: 6px;
    }
    .logo-image {
        height: 40px;
    }
}

/* Mobile menu CTA block */
.nav-cta {
    margin-top: var(--space-4);
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border);
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-3);
}

.nav-cta-btn {
    width: 100%;
}

@media (min-width: 1024px) {
    /* CTA stays in header on desktop, hidden inside nav */
    .nav-cta {
        display: none;
    }
}

.mobile-menu-toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
    min-height: 48px;
    min-width: 48px;
    justify-content: center;
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 3px;
    background: var(--color-text);
    border-radius: var(--radius-full);
    transition: all var(--transition-base);
}

.mobile-menu-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: rotate(45deg) translate(7px, 7px);
}

.mobile-menu-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

.main-nav.is-open {
    display: block;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    padding: var(--space-4);
}

.main-nav.is-open .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
}

.main-nav.is-open .nav-link {
    display: block;
    padding: var(--space-4);
    border-radius: var(--radius-md);
}

.main-nav.is-open .nav-link:hover {
    background-color: var(--color-bg-alt);
}

/* Give mobile menu a nicer panel feel */
.main-nav.is-open {
    border-bottom-left-radius: var(--radius-xl);
    border-bottom-right-radius: var(--radius-xl);
    margin: 0 var(--container-padding);
    left: var(--container-padding);
    right: var(--container-padding);
}

@media (min-width: 1024px) {
    .main-nav.is-open {
        margin: 0;
        left: 0;
        right: 0;
        border-radius: 0;
    }
}

@media (min-width: 1024px) {
    .main-nav {
        display: block;
    }
    
    .mobile-menu-toggle {
        display: none;
    }
}

/* ========================================
   Footer - Styles moved to footer.php inline
======================================== */

/* ========================================
   Hero Section - Premium
======================================== */
.hero-section {
    padding: var(--space-20) 0 var(--space-16);
    position: relative;
    overflow: hidden;
    min-height: 90vh;
    display: flex;
    align-items: center;
}

/* Hero Background Layers */
.hero-background {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 25%, #4ade80 50%, #22c55e 75%, #16a34a 100%);
    background-size: 200% 200%;
    animation: gradientShift 20s ease infinite;
}

.hero-pattern {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(circle at 2px 2px, rgba(255,255,255,0.15) 1px, transparent 0);
    background-size: 40px 40px;
    opacity: 0.4;
}

.hero-glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.6;
    pointer-events: none;
    animation: float 20s ease-in-out infinite;
}

.hero-glow-1 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(34, 197, 94, 0.6) 0%, transparent 70%);
    top: -200px;
    left: -200px;
    animation-delay: 0s;
}

.hero-glow-2 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(22, 163, 74, 0.5) 0%, transparent 70%);
    bottom: -150px;
    right: -150px;
    animation-delay: 5s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-section .container {
    max-width: 1200px;
    position: relative;
    z-index: 1;
}

.hero-content {
    text-align: center;
    max-width: 1000px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    color: var(--color-text-inverse);
    border-radius: var(--radius-full);
    font-family: var(--font-heading);
    font-size: var(--text-sm);
    font-weight: 600;
    margin-bottom: var(--space-8);
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    animation: fadeInUp 0.8s ease;
}

.badge-icon {
    font-size: var(--text-lg);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 5.5rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: var(--space-8);
    color: var(--color-text-inverse);
    text-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 1s ease 0.2s both;
}

.title-line {
    display: block;
}

.title-highlight {
    background: linear-gradient(135deg, #ffffff 0%, #f0fdf4 50%, #ffffff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: none;
    position: relative;
}

.title-highlight::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.8), transparent);
    border-radius: var(--radius-full);
    animation: slideIn 1.5s ease 0.5s both;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        width: 0;
    }
    to {
        width: 100%;
    }
}

.hero-description {
    font-size: clamp(1.125rem, 3vw, 1.5rem);
    color: rgba(255, 255, 255, 0.95);
    line-height: 1.8;
    margin-bottom: var(--space-12);
    max-width: 750px;
    margin-left: auto;
    margin-right: auto;
    text-shadow: 0 2px 15px rgba(0, 0, 0, 0.2);
    animation: fadeInUp 1s ease 0.4s both;
    font-weight: 400;
}

.hero-actions {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-16);
    animation: fadeInUp 1s ease 0.6s both;
}

.hero-actions .btn {
    width: 100%;
    max-width: 280px;
    min-height: 60px;
    font-size: var(--text-lg);
    font-weight: 700;
    padding: 1.25rem 2.5rem;
}

.btn-hero-primary {
    background: linear-gradient(135deg, #ffffff 0%, #f0fdf4 100%);
    color: #16a34a;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3), 0 0 0 1px rgba(255, 255, 255, 0.2);
}

.btn-hero-primary:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 30px 70px rgba(0, 0, 0, 0.4), 0 0 0 1px rgba(255, 255, 255, 0.3);
    background: linear-gradient(135deg, #ffffff 0%, #dcfce7 100%);
}

.btn-hero-primary svg {
    transition: transform var(--transition-base);
}

.btn-hero-primary:hover svg {
    transform: translateX(4px);
}

.btn-hero-secondary {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 2px solid rgba(255, 255, 255, 0.4);
    color: rgba(255, 255, 255, 0.98);
}

.btn-hero-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.6);
    transform: translateY(-2px);
}

@media (min-width: 640px) {
    .hero-actions {
        flex-direction: row;
        gap: var(--space-6);
    }
    .hero-actions .btn {
        width: auto;
        min-width: 240px;
    }
}

@media (max-width: 420px) {
    .hero-title {
        font-size: clamp(2rem, 8vw, 3.5rem);
    }
    .hero-actions .btn {
        padding: 1rem 2rem;
        min-height: 56px;
        font-size: var(--text-base);
    }
}

.hero-trust {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
    justify-content: center;
    align-items: center;
    padding-top: var(--space-12);
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    animation: fadeInUp 1s ease 0.8s both;
}

@media (min-width: 640px) {
    .hero-trust {
        grid-template-columns: repeat(4, 1fr);
        gap: var(--space-6);
    }
}

@media (min-width: 768px) {
    .hero-content {
        max-width: 1100px;
    }
}

.trust-item {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-4) var(--space-5);
    background: rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(20px);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(255, 255, 255, 0.25);
    transition: all var(--transition-base);
    cursor: default;
}

.trust-item:hover {
    background: rgba(255, 255, 255, 0.18);
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.trust-icon {
    font-size: var(--text-2xl);
    line-height: 1;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

.trust-text {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.trust-text strong {
    font-family: var(--font-heading);
    font-size: var(--text-sm);
    font-weight: 700;
    color: rgba(255, 255, 255, 1);
    line-height: 1.2;
}

.trust-text span {
    font-size: var(--text-xs);
    color: rgba(255, 255, 255, 0.85);
    font-weight: 500;
}

/* ========================================
   Features Section
======================================== */
.features-section {
    padding: var(--space-20) 0;
    background-color: var(--color-bg);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-16);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.section-subtitle {
    display: inline-block;
    font-family: var(--font-heading);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-3);
    padding: var(--space-2) var(--space-4);
    background: var(--color-primary-light);
    border-radius: var(--radius-full);
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--space-4);
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 50%, #4ade80 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-card {
    text-align: center;
    padding: var(--space-8);
    background: var(--color-surface);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
}

.feature-card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-6px);
    border-color: var(--color-primary-light);
}

.feature-icon {
    width: 90px;
    height: 90px;
    margin: 0 auto var(--space-6);
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 50%, #4ade80 100%);
    border-radius: var(--radius-2xl);
    font-size: var(--text-4xl);
    box-shadow: 0 10px 30px rgba(22, 163, 74, 0.3);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.feature-card:hover .feature-icon {
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 15px 40px rgba(22, 163, 74, 0.4);
}

.feature-title {
    font-family: var(--font-heading);
    font-size: var(--text-xl);
    font-weight: 600;
    margin-bottom: var(--space-3);
}

.feature-description {
    color: var(--color-text-secondary);
    font-size: var(--text-base);
    line-height: 1.7;
}

/* ========================================
   Stats Section
======================================== */
.stats-section {
    padding: var(--space-20) 0;
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 50%, #4ade80 100%);
    color: var(--color-text-inverse);
    position: relative;
    overflow: hidden;
}

.stats-section::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 30% 50%, rgba(255,255,255,0.1) 0%, transparent 50%);
    pointer-events: none;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
}

@media (min-width: 768px) {
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.stat-item {
    text-align: center;
    padding: var(--space-8);
    position: relative;
    z-index: 1;
    transition: transform var(--transition-base);
}

.stat-item:hover {
    transform: translateY(-5px);
}

.stat-number {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 6vw, 5rem);
    font-weight: 900;
    line-height: 1;
    margin-bottom: var(--space-3);
    color: var(--color-text-inverse);
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    background: linear-gradient(135deg, #ffffff 0%, #f0fdf4 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: var(--text-lg);
    opacity: 0.95;
    font-weight: 600;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
    letter-spacing: 0.5px;
}

/* ========================================
   Testimonials Section
======================================== */
.testimonials-section {
    padding: var(--space-20) 0;
    background:
        radial-gradient(circle at 20% 10%, rgba(124, 58, 237, 0.12), transparent 55%),
        radial-gradient(circle at 80% 70%, rgba(20, 184, 166, 0.10), transparent 55%),
        linear-gradient(180deg, var(--color-bg-alt) 0%, #FFFFFF 100%);
}

.testimonial-card {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(10px);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    border: 1px solid rgba(124, 58, 237, 0.14);
    position: relative;
    overflow: hidden;
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.testimonial-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-2xl);
    border-color: rgba(124, 58, 237, 0.28);
}

.testimonial-card::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(124, 58, 237, 0.08), rgba(20, 184, 166, 0.06));
    opacity: 0;
    transition: opacity var(--transition-base);
    pointer-events: none;
}

.testimonial-card:hover::after {
    opacity: 1;
}

.testimonial-card::before {
    content: '"';
    position: absolute;
    top: var(--space-4);
    left: var(--space-6);
    font-family: var(--font-heading);
    font-size: 5rem;
    color: var(--color-primary-light);
    line-height: 1;
    opacity: 0.3;
}

.testimonial-rating {
    display: inline-flex;
    align-items: center;
    gap: 2px;
    font-family: var(--font-heading);
    font-weight: 700;
    letter-spacing: 0.08em;
    font-size: 0.95rem;
    color: #F59E0B;
    margin-bottom: var(--space-4);
    position: relative;
    z-index: 1;
}

.testimonial-text {
    font-size: var(--text-lg);
    line-height: 1.8;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
    font-style: italic;
    position: relative;
    z-index: 1;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border);
}

.testimonial-avatar {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-full);
    background: var(--color-primary-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-2xl);
    font-weight: 700;
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-md);
}

.testimonial-info h4 {
    font-family: var(--font-heading);
    font-size: var(--text-base);
    font-weight: 600;
    margin-bottom: var(--space-1);
}

.testimonial-info p {
    font-size: var(--text-sm);
    color: var(--color-text-muted);
    margin: 0;
}

/* ========================================
   Static Pages & Generic Sections
   (Giới thiệu, Hướng dẫn, Chính sách, Liên hệ...)
======================================== */
.section {
    padding: var(--space-16) 0;
    background-color: var(--color-bg);
}

.page-header {
    padding: var(--space-16) 0 var(--space-10);
    background:
        radial-gradient(circle at top left, rgba(124, 58, 237, 0.18), transparent 55%),
        linear-gradient(180deg, #0F172A 0%, #020617 60%, #020617 100%);
    color: var(--color-text-inverse);
}

.page-header .container {
    max-width: var(--container-narrow);
}

.page-header h1 {
    font-size: clamp(1.9rem, 4vw, 2.6rem);
    color: var(--color-text-inverse);
    margin-bottom: var(--space-3);
}

.page-header .lead {
    color: rgba(255, 255, 255, 0.8);
}

.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    list-style: none;
    font-size: var(--text-sm);
    margin-bottom: var(--space-4);
    padding: 0;
}

.breadcrumb-item a {
    color: rgba(226, 232, 240, 0.9);
}

.breadcrumb-item.active {
    color: rgba(148, 163, 184, 0.9);
}

.breadcrumb-item + .breadcrumb-item::before {
    content: '/';
    margin: 0 4px;
    color: rgba(148, 163, 184, 0.8);
}

.content {
    padding: var(--space-16) 0;
    background-color: var(--color-bg);
}

.content-body {
    background-color: var(--color-surface);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-border);
}

.content-body h2 {
    margin-top: var(--space-6);
}

.content-body p + h2,
.content-body p + h3 {
    margin-top: var(--space-8);
}

.content-body ul,
.content-body ol {
    margin-left: var(--space-4);
    margin-bottom: var(--space-4);
}

.content-body li {
    margin-bottom: var(--space-2);
}

/* ========================================
   Contact page (ho-tro)
======================================== */
.contact-section {
    display: grid;
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1.6fr);
    gap: var(--space-10);
    align-items: flex-start;
}

@media (max-width: 768px) {
    .contact-section {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }
}

.contact-info h3,
.contact-form h3 {
    font-size: var(--text-xl);
    margin-bottom: var(--space-3);
}

.contact-details {
    list-style: none;
    margin: var(--space-4) 0 0;
    padding: 0;
}

.contact-details li {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
}

.contact-icon {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-full);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
    flex: 0 0 auto;
}

.contact-form {
    background-color: var(--color-surface);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-border);
}

.form-group {
    margin-bottom: var(--space-4);
}

.form-label {
    display: block;
    font-weight: 600;
    margin-bottom: 6px;
}

.form-input,
.form-textarea {
    width: 100%;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    padding: var(--space-3);
    font-family: var(--font-body);
    font-size: 0.95rem;
    outline: none;
    background: #FFFFFF;
}

.form-input:focus,
.form-textarea:focus {
    border-color: rgba(124, 58, 237, 0.6);
    box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.18);
}

.form-textarea {
    min-height: 140px;
    resize: vertical;
}

/* FAQ block (trang Hướng dẫn) */
.faq-section {
    margin-top: var(--space-8);
}

.faq-item {
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    margin-bottom: var(--space-3);
    background-color: var(--color-surface);
    overflow: hidden;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-4) var(--space-5);
    cursor: pointer;
    font-weight: 600;
}

.faq-answer {
    padding: 0 var(--space-5) var(--space-4);
    border-top: 1px solid var(--color-border-light);
}

/* Keyword hero (trang Tin mới) */
.keyword-hero {
    padding: var(--space-16) 0 var(--space-12);
    background:
        radial-gradient(circle at top, rgba(15,23,42,1) 0, rgba(15,23,42,0.96) 45%, #020617 100%);
    color: var(--color-text-inverse);
    text-align: center;
}

.keyword-tag {
    display: inline-flex;
    padding: 6px 14px;
    border-radius: var(--radius-full);
    background: rgba(15, 118, 110, 0.18);
    border: 1px solid rgba(34, 211, 238, 0.35);
    font-size: var(--text-sm);
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.keyword-hero h1 {
    margin-top: var(--space-4);
    color: var(--color-text-inverse);
}

/* Post layout (trang chi tiết bài viết) */
.post-header {
    padding-bottom: var(--space-8);
}

.post-layout {
    padding: var(--space-16) 0;
}

.post-grid {
    display: grid;
    grid-template-columns: minmax(0, 2fr);
    gap: var(--space-8);
}

@media (min-width: 1024px) {
    .post-grid {
        grid-template-columns: minmax(0, 2.2fr) minmax(0, 1fr);
    }
}

.post-main,
.post-aside {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
}

.post-cover img {
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
}

.post-aside-card {
    background-color: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.post-aside-list li {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--space-2);
}

/* ========================================
   CTA Section
======================================== */
.cta-section {
    padding: var(--space-24) 0;
    background: linear-gradient(135deg, #16a34a 0%, #22c55e 50%, #4ade80 100%);
    color: var(--color-text-inverse);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.cta-content {
    max-width: 700px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.cta-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    margin-bottom: var(--space-4);
    color: var(--color-text-inverse);
}

.cta-description {
    font-size: var(--text-xl);
    margin-bottom: var(--space-10);
    opacity: 0.95;
    line-height: 1.7;
}

.cta-section .btn-primary {
    background: var(--color-text-inverse);
    color: var(--color-primary);
    font-size: var(--text-lg);
    padding: 1.25rem 2.5rem;
}

.cta-section .btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: var(--shadow-2xl);
}

/* ========================================
   Utility Classes
======================================== */
.text-center {
    text-align: center;
}

.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-10 { margin-top: var(--space-10); }
.mt-12 { margin-top: var(--space-12); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

/* ========================================
   Responsive
======================================== */
@media (min-width: 640px) {
    :root {
        --container-padding: 1.5rem;
    }
}

@media (min-width: 1024px) {
    :root {
        --container-padding: 2rem;
    }
}

/* ========================================
   Print Styles
======================================== */
@media print {
    .site-header,
    .site-footer,
    .btn {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
}