:root {
    --bg-dark: #050505;
    --bg-card: rgba(255, 255, 255, 0.03);
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --accent-red: #c91823;
    --accent-red-hover: #e01c28;
    --accent-gold: #d4af37;
    --border-color: rgba(255, 255, 255, 0.1);
    
    --font-heading: 'Inter', sans-serif;
    --font-body: 'Inter', sans-serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
    width: 100%;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-body);
    line-height: 1.6;
    overflow-x: hidden;
    width: 100%;
}

/* Background effects */
body::before {
    content: '';
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: radial-gradient(circle at 50% 0%, rgba(201, 24, 35, 0.15) 0%, transparent 50%),
                radial-gradient(circle at 100% 100%, rgba(212, 175, 55, 0.05) 0%, transparent 50%);
    z-index: -1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Typography */
h1, h2, h3 {
    font-family: var(--font-heading);
    font-weight: 800;
    line-height: 1.2;
}

.highlight {
    color: var(--accent-red);
    text-shadow: 0 0 20px rgba(201, 24, 35, 0.4);
}

.text-red {
    color: var(--accent-red);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 14px 28px;
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font-body);
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.3s ease;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-red), #99121a);
    color: #fff;
    border: none;
    box-shadow: 0 4px 15px rgba(201, 24, 35, 0.4);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--accent-red-hover), var(--accent-red));
    box-shadow: 0 6px 20px rgba(201, 24, 35, 0.6);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    border-color: var(--text-primary);
    background: rgba(255,255,255,0.05);
}

.btn-outline {
    background: transparent;
    color: var(--accent-red);
    border: 1px solid var(--accent-red);
    padding: 10px 20px;
}

.btn-outline:hover {
    background: var(--accent-red);
    color: #fff;
}

/* Glassmorphism */
.glass {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 12px;
}

/* Top Banner */
.top-banner {
    background: var(--accent-red);
    color: #fff;
    text-align: center;
    padding: 10px;
    font-size: 0.9rem;
    font-weight: 600;
}

.top-banner span {
    font-variant-numeric: tabular-nums;
    font-weight: 800;
}

/* Navbar */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 5%;
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(5, 5, 5, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: 2px;
}

.logo span {
    color: var(--accent-red);
}

.brand-symbol-link {
    width: 76px;
    height: 76px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
    border-radius: 18px;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(212, 175, 55, 0.22);
    transition: transform 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.brand-symbol-image {
    display: block;
    width: 68px;
    height: 68px;
    object-fit: contain;
}

.brand-symbol-link:hover {
    transform: translateY(-2px);
    border-color: rgba(212, 175, 55, 0.55);
    background: rgba(255, 255, 255, 0.07);
}

.brand-symbol-link:focus-visible {
    outline: 3px solid rgba(212, 175, 55, 0.65);
    outline-offset: 3px;
}

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

/* Hero Section */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
    min-height: 85vh;
    padding: 0 5%;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.hero-content .subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
    max-width: 90%;
}

.hero-actions {
    display: flex;
    gap: 15px;
    margin-bottom: 30px;
}

.social-proof {
    display: flex;
    align-items: center;
    gap: 15px;
}

.avatars {
    display: flex;
}

.avatars img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid var(--bg-dark);
    margin-left: -15px;
}

.avatars img:first-child {
    margin-left: 0;
}

.social-proof p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.hero-visual {
    position: relative;
    height: 600px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.book-mockup-cluster {
    position: relative;
    width: 100%;
    height: 100%;
}

.book-cover {
    position: absolute;
    border-radius: 4px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
}

.book-cover img {
    width: 100%;
    height: auto;
    border-radius: 4px;
    border: 1px solid rgba(255,255,255,0.1);
    transition: all 0.6s ease;
}

.b-1 {
    width: 290px;
    z-index: 10;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%) rotate(0deg);
    filter: brightness(1.1);
}

.b-1 img {
    border: 2px solid var(--accent-gold);
    box-shadow: 0 0 30px rgba(212, 175, 55, 0.6);
}

.b-2 {
    width: 200px;
    z-index: 2;
    left: 15%;
    top: 40%;
    transform: rotate(-10deg);
    filter: brightness(0.6);
}

.b-3 {
    width: 200px;
    z-index: 1;
    right: 15%;
    top: 45%;
    transform: rotate(15deg);
    filter: brightness(0.6);
}

.b-4 {
    width: 170px;
    z-index: 0;
    right: 0%;
    top: 55%;
    transform: rotate(25deg);
    filter: brightness(0.4);
}

.book-cover:not(.b-1):hover {
    filter: brightness(0.9);
    z-index: 5;
    transform: scale(1.05) rotate(0deg);
}

/* Pain Points */
.pain-points {
    padding: 100px 0;
    background: linear-gradient(to bottom, transparent, rgba(201, 24, 35, 0.03), transparent);
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.card {
    padding: 40px 30px;
    text-align: center;
    transition: transform 0.3s ease;
}

.card:hover {
    transform: translateY(-10px);
    border-color: rgba(201, 24, 35, 0.3);
}

.icon-red {
    font-size: 2.5rem;
    color: var(--accent-red);
    margin-bottom: 20px;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
}

.card p {
    color: var(--text-secondary);
}

/* Series Details */
.series-details {
    padding: 100px 0;
}

.book-row {
    display: flex;
    align-items: center;
    gap: 60px;
    margin-bottom: 100px;
}

.book-row.reverse {
    flex-direction: row-reverse;
}

.book-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.book-image img {
    max-width: 350px;
    border-radius: 8px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.6);
    transition: transform 0.4s ease;
}

.book-image img:hover {
    transform: scale(1.03) translateY(-10px);
}

.book-info {
    flex: 1;
}

.vol-badge {
    display: inline-block;
    padding: 5px 15px;
    border: 1px solid var(--accent-gold);
    color: var(--accent-gold);
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 2px;
    margin-bottom: 15px;
}

.book-info h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.quote {
    font-family: var(--font-heading);
    font-style: italic;
    font-size: 1.2rem;
    color: var(--text-secondary);
    border-left: 3px solid var(--accent-red);
    padding-left: 15px;
    margin-bottom: 20px;
}

.book-info p {
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.benefits-list {
    list-style: none;
}

.benefits-list li {
    margin-bottom: 10px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.benefits-list i {
    color: var(--accent-gold);
    margin-top: 5px;
}

/* Testimonials */
.testimonials {
    padding: 100px 0;
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.testimonial-card {
    padding: 40px;
}

.stars {
    color: var(--accent-gold);
    margin-bottom: 20px;
}

.testimonial-card p {
    font-size: 1.1rem;
    font-style: italic;
    margin-bottom: 20px;
    color: #e4e4e7;
}

.user-info {
    border-top: 1px solid var(--border-color);
    padding-top: 15px;
    color: var(--text-secondary);
}

.user-info strong {
    color: var(--text-primary);
}

.pagination {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 40px;
}

.page-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
}

.page-btn:hover, .page-btn.active {
    background: var(--accent-red);
    color: white;
    border-color: var(--accent-red);
}

/* Pricing Section */
.pricing-section {
    padding: 100px 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 30px;
    align-items: center;
    margin-top: 50px;
}

.pricing-card {
    padding: 40px;
    border-radius: 12px;
    text-align: left;
    position: relative;
    border: 1px solid var(--border-color);
}

.highlight-card {
    border: 2px solid var(--accent-red);
    box-shadow: 0 0 30px rgba(201, 24, 35, 0.2);
    transform: scale(1.05);
    background: linear-gradient(135deg, rgba(201, 24, 35, 0.05) 0%, rgba(212, 175, 55, 0.05) 100%);
    z-index: 2;
}

.best-value-badge {
    position: absolute;
    top: -15px;
    right: 20px;
    background: var(--accent-red);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-weight: bold;
    font-size: 0.9rem;
    box-shadow: 0 5px 15px rgba(201, 24, 35, 0.4);
}

.pricing-card h3 {
    font-size: 1.8rem;
    margin-bottom: 10px;
}

.pricing-desc {
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.pricing-card .price {
    margin-bottom: 30px;
    display: flex;
    align-items: baseline;
    gap: 15px;
}

.pricing-card .old-price {
    font-size: 1.5rem;
    color: var(--text-secondary);
    text-decoration: line-through;
}

.pricing-card .new-price {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
}

.pricing-card .unit {
    color: var(--text-secondary);
}

.disabled {
    opacity: 0.5;
}

/* About Author */
.about-author {
    padding: 100px 0;
    background-color: rgba(255, 255, 255, 0.02);
    border-top: 1px solid var(--border-color);
}

.author-grid {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 50px;
    align-items: center;
}

.author-image img {
    width: 100%;
    border-radius: 12px;
    box-shadow: 15px 15px 0 var(--accent-gold);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.author-image img:hover {
    transform: translate(-5px, -5px);
    box-shadow: 20px 20px 0 var(--accent-red);
}

.author-info p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 15px;
}

.author-info strong {
    color: var(--text-primary);
}

/* Removed duplicate floating-contact block */

/* CTA Section */
.final-cta {
    padding: 100px 0;
}

.cta-box {
    text-align: center;
    padding: 80px 40px;
    background: linear-gradient(135deg, rgba(201, 24, 35, 0.05) 0%, rgba(212, 175, 55, 0.05) 100%);
    border: 1px solid rgba(201, 24, 35, 0.2);
}

.cta-box h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.cta-box p {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1.1rem;
}

.price {
    margin-bottom: 30px;
}

.old-price {
    text-decoration: line-through;
    color: var(--text-secondary);
    margin-right: 15px;
    font-size: 1.2rem;
}

.new-price {
    color: var(--accent-gold);
    font-weight: 800;
    font-size: 1.5rem;
}

.guarantee {
    margin-top: 20px;
    font-size: 0.9rem !important;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.pulse {
    animation: pulse-red 2s infinite;
}

@keyframes pulse-red {
    0% {
        box-shadow: 0 0 0 0 rgba(201, 24, 35, 0.7);
    }
    70% {
        box-shadow: 0 0 0 15px rgba(201, 24, 35, 0);
    }
    100% {
        box-shadow: 0 0 0 0 rgba(201, 24, 35, 0);
    }
}

/* Footer */
footer {
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-logo {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 800;
    margin-bottom: 10px;
}
.footer-logo span { color: var(--accent-red); }
footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Animations */
.reveal {
    opacity: 0;
    transform: translateY(50px);
    transition: all 0.8s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Floating Contact Buttons */
.floating-contact {
    position: fixed;
    bottom: 30px;
    right: 30px;
    display: flex;
    flex-direction: column;
    gap: 15px;
    z-index: 999;
}

.contact-btn {
    width: 55px;
    height: 55px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    box-shadow: 0 4px 15px rgba(0,0,0,0.4);
    transition: transform 0.3s ease;
}

.contact-btn:hover {
    transform: scale(1.1);
    color: white;
}

.phone-btn {
    background: linear-gradient(135deg, var(--accent-gold), #b5952f);
    animation: pulse-gold 2s infinite;
}

.phone-btn i {
    font-size: 1.3rem;
    color: #000; /* Màu đen tạo sự tương phản sang trọng trên nền vàng */
}

.zalo-btn {
    background: linear-gradient(135deg, var(--accent-red), #99121a);
    animation: pulse-red-icon 2s infinite;
    animation-delay: 1s;
}

@keyframes pulse-gold {
    0% { box-shadow: 0 0 0 0 rgba(212, 175, 55, 0.7); }
    70% { box-shadow: 0 0 0 15px rgba(212, 175, 55, 0); }
    100% { box-shadow: 0 0 0 0 rgba(212, 175, 55, 0); }
}

@keyframes pulse-red-icon {
    0% { box-shadow: 0 0 0 0 rgba(201, 24, 35, 0.7); }
    70% { box-shadow: 0 0 0 15px rgba(201, 24, 35, 0); }
    100% { box-shadow: 0 0 0 0 rgba(201, 24, 35, 0); }
}

/* Responsive */
@media (max-width: 992px) {
    .hero {
        display: flex;
        flex-direction: column;
        text-align: center;
        margin-top: 40px;
        gap: 20px;
    }
    .hero-visual {
        order: -1; /* Hiển thị ảnh sách lên trước trên mobile */
        width: 100%;
        height: 450px;
    }
    .hero-content {
        order: 1;
    }
    .hero-content h1 {
        font-size: 2.8rem;
    }
    .hero-content .subtitle {
        margin: 0 auto 30px auto;
    }
    .hero-actions {
        justify-content: center;
    }
    .social-proof {
        justify-content: center;
    }
    .book-row, .book-row.reverse {
        flex-direction: column;
        text-align: center;
        gap: 30px;
    }
    .book-row .book-image, .book-row.reverse .book-image {
        order: -1; /* Luôn hiển thị ảnh sách trước thông tin trên mobile */
    }
    .benefits-list li {
        justify-content: center;
    }
    .pricing-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    .highlight-card {
        transform: scale(1);
    }
    .pricing-card {
        padding: 30px;
    }
}

@media (max-width: 768px) {
    .grid-3, .grid-2 {
        grid-template-columns: 1fr;
    }
    .hero-content h1 {
        font-size: 2.2rem;
    }
    .section-title {
        font-size: 2rem;
    }
    .hero-visual {
        height: 350px;
    }
    .b-1 { width: 190px; }
    .b-2 { width: 130px; left: 5%; top: 40%; }
    .b-3 { width: 130px; right: 5%; top: 45%; }
    .b-4 { width: 110px; right: -5%; top: 55%; }
    .pricing-card {
        padding: 20px;
    }
    .pricing-card h3 {
        font-size: 1.4rem;
    }
    .pricing-card .new-price {
        font-size: 2rem !important;
    }
    .pricing-card .old-price {
        font-size: 1.2rem;
    }
    .best-value-badge {
        font-size: 0.8rem;
        padding: 5px 10px;
        right: 10px;
    }
    
    .author-grid {
        grid-template-columns: 1fr;
    }
    
    .author-image {
        max-width: 300px;
        margin: 0 auto 40px;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 1.8rem;
    }
    .hero-content .subtitle {
        font-size: 0.95rem;
    }
    .section-title {
        font-size: 1.6rem;
    }
    .book-info h2 {
        font-size: 1.8rem;
    }
    .hero-visual {
        height: 250px;
    }
    .b-1 { width: 140px; }
    .b-2 { width: 90px; left: 5%; top: 35%; }
    .b-3 { width: 90px; right: 5%; top: 40%; }
    .b-4 { width: 75px; right: -2%; top: 50%; }
    
    .floating-contact {
        bottom: 20px;
        right: 20px;
    }
    .contact-btn {
        width: 45px;
        height: 45px;
    }
    .zalo-btn span {
        font-size: 0.7rem !important;
    }
    
    .book-image img {
        max-width: 220px;
    }
    
    .book-row {
        margin-bottom: 60px;
    }
    
    .navbar {
        display: flex;
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
        gap: 8px;
        padding: 10px 4%;
    }

    .brand-symbol-link {
        width: 54px;
        height: 54px;
        flex: 0 0 54px;
        border-radius: 12px;
        margin-left: 0;
        margin-right: auto;
    }

    .brand-symbol-image {
        width: 48px;
        height: 48px;
    }
    
    .nav-actions {
        display: flex;
        flex-direction: row;
        flex-wrap: wrap;
        gap: 6px;
        align-items: center;
        justify-content: flex-end;
        margin-left: auto;
    }
    .hero-actions {
        flex-direction: column;
        gap: 15px;
        padding: 0;
        width: 100%;
    }
    .hero-actions .btn {
        width: 100%;
        justify-content: center;
    }
    .btn {
        padding: 12px 20px;
        font-size: 0.9rem;
    }
    
    .nav-actions .btn {
        width: auto !important;
        padding: 6px 8px !important;
        font-size: 0.74rem !important;
        gap: 4px !important;
        white-space: nowrap;
    }
    
    .top-banner {
        font-size: 0.8rem;
        padding: 8px 10px;
    }
    
    .pricing-card h3 {
        font-size: 1.2rem;
    }
    .pricing-card .new-price {
        font-size: 1.8rem !important;
    }
    .pricing-card .old-price {
        font-size: 1rem;
    }
    
    .pain-points, .series-details, .testimonials, .pricing-section, .about-author {
        padding: 60px 0;
    }
}

/* Audio Books Section */
.audio-books-section {
    padding: 60px 0 100px;
}

.audio-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.audio-card {
    display: flex;
    padding: 30px;
    gap: 30px;
    align-items: center;
}

.audio-cover {
    width: 200px;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.audio-info {
    flex: 1;
}

.audio-info h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    font-family: var(--font-heading);
}

.player-container {
    margin-top: 20px;
}

.unlock-btn {
    width: 100%;
}

/* Video Course Player */
.video-course-container {
    margin-top: 20px;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.video-player-wrapper {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 Aspect Ratio */
    height: 0;
    background: #000;
}

.video-player-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.chapter-list {
    padding: 20px;
}

.chapter-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.chapter-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 12px 15px;
    border-radius: 6px;
    text-align: left;
    cursor: pointer;
    font-family: var(--font-body);
    font-size: 0.95rem;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.chapter-btn i {
    color: var(--accent-gold);
    font-size: 0.8rem;
}

.chapter-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--text-secondary);
}

.chapter-btn.active {
    background: var(--accent-red);
    border-color: var(--accent-red);
    color: #fff;
}

.chapter-btn.active i {
    color: #fff;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-dark);
    padding: 40px;
    width: 90%;
    max-width: 400px;
    border-radius: 12px;
    position: relative;
    border: 1px solid var(--border-color);
    box-shadow: 0 20px 50px rgba(0,0,0,0.5);
    text-align: center;
    animation: modalSlideIn 0.3s ease-out;
}

@keyframes modalSlideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.close-modal {
    color: var(--text-secondary);
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    position: absolute;
    top: 10px;
    right: 20px;
}

.close-modal:hover {
    color: var(--accent-red);
}

.form-input {
    width: 100%;
    padding: 12px 15px;
    margin-top: 10px;
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border-color);
    color: #fff;
    border-radius: 4px;
    font-family: var(--font-body);
    font-size: 1rem;
    outline: none;
    transition: all 0.3s;
}

.form-input:focus {
    border-color: var(--accent-red);
    box-shadow: 0 0 10px rgba(201, 24, 35, 0.2);
}

.shake {
    animation: shake 0.5s;
}

@keyframes shake {
    0% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    50% { transform: translateX(10px); }
    75% { transform: translateX(-10px); }
    100% { transform: translateX(0); }
}

/* Responsive Audio Grid */
@media (max-width: 992px) {
    .audio-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .audio-card {
        flex-direction: column;
        text-align: center;
    }
    
    .audio-cover {
        width: 150px;
    }
}

/* Audio Player Section specific styles */
.player-header {
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 15px;
}

.chapter-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    cursor: pointer;
    transition: all 0.3s ease;
}

.chapter-item:hover {
    background: rgba(255, 255, 255, 0.08);
}

.chapter-item.active {
    background: rgba(201, 24, 35, 0.1);
    border-color: var(--accent-red);
    box-shadow: inset 4px 0 0 var(--accent-red);
}

.chapter-item.active .chapter-title, .chapter-item.active .play-icon {
    color: var(--accent-red);
}

.chapter-info {
    display: flex;
    flex-direction: column;
}

.chapter-num {
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 4px;
}

.chapter-title {
    font-size: 1rem;
    font-weight: 600;
}

.play-icon {
    color: var(--text-secondary);
}

/* Custom Scrollbar */
.custom-scroll::-webkit-scrollbar {
    width: 6px;
}
.custom-scroll::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.02);
}
.custom-scroll::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 10px;
}
.custom-scroll::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* Fix mobile audio player layout */
@media (max-width: 768px) {
    .player-layout.grid-2 {
        grid-template-columns: 1fr !important;
        gap: 20px;
    }
    
    .playlist.glass {
        height: 400px !important;
    }
    
    #player-book-title {
        font-size: 1.1rem !important;
    }
}

/* =========================================================
   BOOK BUY ACTIONS – Nút mua + Google Play
   ========================================================= */
.book-buy-actions {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 15px;
}

.btn-outline-google {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 9px 18px;
    font-size: 0.85rem;
    font-weight: 600;
    font-family: var(--font-body);
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.3s ease;
    cursor: pointer;
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid rgba(255,255,255,0.15);
    letter-spacing: 0.5px;
    width: 100%;
    justify-content: center;
}

.btn-outline-google:hover {
    border-color: #4285f4;
    color: #4285f4;
    background: rgba(66, 133, 244, 0.05);
}

/* =========================================================
   CHECKOUT MODAL – Cửa sổ thanh toán
   ========================================================= */
.checkout-modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 2000;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    align-items: center;
    justify-content: center;
    padding: 16px;
    overflow-y: auto;
}

.checkout-modal-overlay.checkout-modal-open {
    animation: overlayFadeIn 0.25s ease-out;
}

@keyframes overlayFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.checkout-modal-box {
    background: #0d0d0d;
    border: 1px solid rgba(201, 24, 35, 0.3);
    border-radius: 16px;
    width: 100%;
    max-width: 520px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.7), 0 0 40px rgba(201, 24, 35, 0.1);
    animation: modalSlideUp 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    scroll-behavior: smooth;
}

.checkout-modal-box::-webkit-scrollbar {
    width: 4px;
}
.checkout-modal-box::-webkit-scrollbar-track {
    background: transparent;
}
.checkout-modal-box::-webkit-scrollbar-thumb {
    background: rgba(201, 24, 35, 0.4);
    border-radius: 2px;
}

@keyframes modalSlideUp {
    from {
        transform: translateY(40px) scale(0.95);
        opacity: 0;
    }
    to {
        transform: translateY(0) scale(1);
        opacity: 1;
    }
}

/* Header modal */
.checkout-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.checkout-modal-logo {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 800;
    letter-spacing: 2px;
    color: var(--text-primary);
}

.checkout-modal-logo span {
    color: var(--accent-red);
}

.checkout-close-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 28px;
    cursor: pointer;
    line-height: 1;
    padding: 4px 8px;
    border-radius: 4px;
    transition: color 0.2s, background 0.2s;
}

.checkout-close-btn:hover {
    color: var(--accent-red);
    background: rgba(201, 24, 35, 0.1);
}

/* Product info */
.checkout-product-info {
    display: flex;
    gap: 16px;
    padding: 20px 24px;
    background: linear-gradient(135deg, rgba(201, 24, 35, 0.04), rgba(212, 175, 55, 0.04));
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.checkout-product-img {
    width: 80px;
    height: 112px;
    object-fit: cover;
    border-radius: 6px;
    box-shadow: 0 8px 20px rgba(0,0,0,0.5);
    flex-shrink: 0;
}

.checkout-product-details {
    flex: 1;
    min-width: 0;
}

.checkout-product-badge {
    display: inline-block;
    padding: 3px 10px;
    border: 1px solid var(--accent-gold);
    color: var(--accent-gold);
    border-radius: 20px;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 1px;
    margin-bottom: 8px;
}

.checkout-product-details h3 {
    font-size: 1rem;
    font-weight: 800;
    margin-bottom: 6px;
    line-height: 1.3;
    color: var(--text-primary);
}

.checkout-price-display {
    margin-bottom: 10px;
}

.checkout-price-display span {
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--accent-red);
    text-shadow: 0 0 20px rgba(201, 24, 35, 0.3);
}

.checkout-benefits {
    list-style: none;
    padding: 0;
    margin: 0;
}

.checkout-benefits li {
    font-size: 0.82rem;
    color: var(--text-secondary);
    display: flex;
    align-items: flex-start;
    gap: 6px;
    margin-bottom: 4px;
}

.checkout-benefits li i {
    color: var(--accent-gold);
    margin-top: 2px;
    flex-shrink: 0;
    font-size: 0.75rem;
}

/* Form */
.checkout-form {
    padding: 24px;
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.required {
    color: var(--accent-red);
}

.checkout-form .form-input {
    width: 100%;
    padding: 13px 16px;
    background: rgba(255, 255, 255, 0.04);
    border: 1.5px solid rgba(255, 255, 255, 0.12);
    color: var(--text-primary);
    border-radius: 8px;
    font-family: var(--font-body);
    font-size: 1rem;
    outline: none;
    transition: all 0.25s;
    -webkit-appearance: none;
}

.checkout-form .form-input:focus {
    border-color: var(--accent-red);
    background: rgba(201, 24, 35, 0.04);
    box-shadow: 0 0 0 3px rgba(201, 24, 35, 0.12);
}

.checkout-form .form-input.input-error {
    border-color: #ff4d4f;
    background: rgba(255, 77, 79, 0.04);
}

.checkout-form .form-input::placeholder {
    color: rgba(255, 255, 255, 0.2);
}

.field-error {
    display: block;
    font-size: 0.8rem;
    color: #ff6b6b;
    margin-top: 5px;
    min-height: 18px;
}

/* Checkbox */
.checkbox-group {
    margin-bottom: 20px;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.checkbox-label input[type="checkbox"] {
    display: none;
}

.checkmark {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.03);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    margin-top: 2px;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark {
    background: var(--accent-red);
    border-color: var(--accent-red);
}

.checkbox-label input[type="checkbox"]:checked + .checkmark::after {
    content: '';
    width: 5px;
    height: 9px;
    border: 2px solid white;
    border-top: none;
    border-left: none;
    transform: rotate(45deg) translate(-1px, -1px);
    display: block;
}

.checkbox-label a {
    color: var(--accent-gold);
    text-decoration: underline;
}

/* Global error */
.checkout-global-error {
    background: rgba(255, 77, 79, 0.1);
    border: 1px solid rgba(255, 77, 79, 0.3);
    color: #ff6b6b;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 0.875rem;
    margin-bottom: 16px;
}

/* Submit button */
.checkout-submit-btn {
    width: 100%;
    padding: 16px;
    font-size: 1rem;
    border: none;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--accent-red), #99121a);
    color: #fff;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(201, 24, 35, 0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    min-height: 56px;
}

.checkout-submit-btn:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--accent-red-hover), var(--accent-red));
    box-shadow: 0 6px 25px rgba(201, 24, 35, 0.6);
    transform: translateY(-1px);
}

.checkout-submit-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

#checkout-btn-text,
#checkout-btn-loading {
    display: flex;
    align-items: center;
    gap: 8px;
}

.checkout-security-note {
    text-align: center;
    font-size: 0.78rem;
    color: var(--text-secondary);
    margin-top: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.checkout-security-note i {
    color: var(--accent-gold);
}

/* =========================================================
   PAYMENT RESULT PAGES – Trang kết quả
   ========================================================= */
.payment-result-page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    text-align: center;
}

.payment-result-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 50px 40px;
    max-width: 500px;
    width: 100%;
    animation: modalSlideUp 0.5s ease-out;
}

.payment-result-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.payment-result-icon.success {
    color: #52c41a;
    text-shadow: 0 0 30px rgba(82, 196, 26, 0.4);
}

.payment-result-icon.failure {
    color: var(--accent-red);
    text-shadow: 0 0 30px rgba(201, 24, 35, 0.4);
}

.payment-result-card h1 {
    font-size: 1.8rem;
    margin-bottom: 12px;
}

.payment-result-card .result-subtitle {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1rem;
    line-height: 1.6;
}

.order-info-table {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    overflow: hidden;
    margin: 20px 0 30px;
    text-align: left;
}

.order-info-row {
    display: flex;
    justify-content: space-between;
    padding: 14px 20px;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    font-size: 0.9rem;
    align-items: center;
    gap: 10px;
}

.order-info-row:last-child {
    border-bottom: none;
}

.order-info-label {
    color: var(--text-secondary);
    flex-shrink: 0;
}

.order-info-value {
    font-weight: 600;
    color: var(--text-primary);
    text-align: right;
    word-break: break-all;
}

.order-info-value.highlight {
    color: var(--accent-gold);
    font-size: 1.1rem;
}

.email-notice {
    background: linear-gradient(135deg, rgba(82, 196, 26, 0.08), rgba(82, 196, 26, 0.04));
    border: 1px solid rgba(82, 196, 26, 0.2);
    border-radius: 10px;
    padding: 16px 20px;
    margin: 20px 0;
    font-size: 0.9rem;
    color: #b7eb8f;
    text-align: left;
}

.email-notice i {
    color: #52c41a;
    margin-right: 8px;
}

.pending-notice {
    background: linear-gradient(135deg, rgba(250, 173, 20, 0.08), rgba(250, 173, 20, 0.04));
    border: 1px solid rgba(250, 173, 20, 0.2);
    border-radius: 10px;
    padding: 16px 20px;
    margin: 20px 0;
    font-size: 0.9rem;
    color: #ffc53d;
}

.pending-notice i {
    margin-right: 8px;
}

.result-actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
}

.btn-zalo-support {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 24px;
    background: #006AF5;
    color: #fff;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-family: var(--font-body);
    transition: all 0.3s;
    font-size: 0.95rem;
}

.btn-zalo-support:hover {
    background: #0057cc;
    color: #fff;
    transform: translateY(-1px);
}

.payment-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,0.2);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-right: 8px;
}

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

/* =========================================================
   RESPONSIVE – Checkout Modal Mobile
   ========================================================= */
@media (max-width: 540px) {
    .checkout-modal-overlay {
        padding: 0;
        align-items: flex-end;
    }

    .checkout-modal-box {
        max-width: 100%;
        max-height: 95vh;
        border-radius: 20px 20px 0 0;
        border-bottom: none;
        animation: modalSlideUpMobile 0.35s cubic-bezier(0.34, 1.2, 0.64, 1);
    }

    @keyframes modalSlideUpMobile {
        from { transform: translateY(100%); }
        to { transform: translateY(0); }
    }

    .checkout-product-info {
        padding: 16px 20px;
    }

    .checkout-product-img {
        width: 64px;
        height: 90px;
    }

    .checkout-product-details h3 {
        font-size: 0.95rem;
    }

    .checkout-price-display span {
        font-size: 1.4rem;
    }

    .checkout-form {
        padding: 20px;
    }

    .checkout-form .form-input {
        font-size: 16px; /* Tránh zoom trên iOS */
        padding: 14px 16px;
    }

    .checkout-submit-btn {
        font-size: 0.95rem;
        min-height: 54px;
    }
}

@media (max-width: 480px) {
    .payment-result-card {
        padding: 30px 20px;
    }

    .order-info-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }

    .order-info-value {
        text-align: left;
    }
}