:root {
    --blue: #0057b7;
    --yellow: #ffdd00;
    --dark-blue: #003b7e;
    --light-yellow: #fff5b8;
    --gray: #333333;
    --light-gray: #f8f8f8;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Montserrat', sans-serif;
}

body {
    font-family: 'Montserrat', sans-serif;
    line-height: 1.6;
    color: var(--gray);
    overflow-x: hidden;
}

header {
    background: linear-gradient(135deg, var(--blue) 0%, var(--blue) 50%, var(--yellow) 50%, var(--yellow) 100%);
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.container {
    width: 85%;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    text-decoration: none;
}

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

.nav-links li {
    margin-left: 2rem;
}

.nav-links a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.nav-links a:hover {
    opacity: 0.8;
}

.hero {
    background: url('img/spine.png') no-repeat center center/cover;
    height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-align: center;
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
}

.hero-content {
    position: relative;
    z-index: 10;
    max-width: 800px;
    padding: 0 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn {
    display: inline-block;
    background: var(--yellow);
    color: var(--blue);
    padding: 0.8rem 2rem;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.3);
}

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

.btn.outline:hover {
    background: var(--yellow);
    color: var(--blue);
}

section {
    padding: 5rem 0;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--blue);
}

.section-header p {
    max-width: 600px;
    margin: 0 auto;
    color: var(--gray);
}

.section-footer {
    text-align: center;
    margin-top: 3rem;
}

.ukrainian-cause {
    background-color: var(--light-gray);
}

.cause-content {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 2rem;
}

.cause-text {
    flex: 1;
    min-width: 300px;
}

.cause-text h3 {
    color: var(--blue);
    margin-bottom: 1rem;
    font-size: 1.8rem;
}

.cause-image {
    flex: 1;
    min-width: 300px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.cause-image img {
    width: 100%;
    height: auto;
    display: block;
}

.book {
    background-color: white;
}

.book-content {
    display: flex;
    align-items: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.book-cover {
    flex: 1;
    min-width: 250px;
    max-width: 350px;
    margin: 0 auto;
}

.book-cover img {
    width: 100%;
    height: auto;
    border-radius: 5px;
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.book-cover img:hover {
    transform: scale(1.02);
}

.book-details {
    flex: 2;
    min-width: 300px;
}

.book-details h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--blue);
}

.book-details p {
    margin-bottom: 1.5rem;
}

.buy-options {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 2rem;
}

.author {
    background-color: var(--light-gray);
}

.author-content {
    display: flex;
    align-items: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.author-image {
    flex: 1;
    min-width: 250px;
    max-width: 350px;
    margin: 0 auto;
}

.author-image img {
    width: 100%;
    height: auto;
    border-radius: 50%;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.author-bio {
    flex: 2;
    min-width: 300px;
}

.author-bio h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--blue);
}

.author-bio p {
    margin-bottom: 1.5rem;
}

.chapters {
    background-color: white;
}

.chapters-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
}

.chapter-card {
    background-color: var(--light-gray);
    border-radius: 10px;
    overflow: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    cursor: pointer;
}

.chapter-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.chapter-content {
    padding: 1.5rem;
}

.chapter-content h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--blue);
}

.language-switch {
    background-color: var(--blue);
    color: white;
}

.language-options {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.language-option {
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    opacity: 0.7;
    transition: all 0.3s ease;
}

.language-option:hover, .language-option.active {
    opacity: 1;
}

.language-option img {
    width: 50px;
    height: 33px;
    border-radius: 5px;
    margin-bottom: 0.5rem;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.audio-section {
    background-color: var(--light-yellow);
}

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

.audio-player {
    max-width: 600px;
    margin: 2rem auto;
    padding: 2rem;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.audio-player h3 {
    margin-bottom: 1.5rem;
    color: var(--blue);
}

.player-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
}

.chapter-selector {
    width: 100%;
    padding: 0.8rem;
    border-radius: 5px;
    border: 1px solid #ddd;
    margin-bottom: 1.5rem;
}

footer {
    background-color: var(--blue);
    color: white;
    padding: 3rem 0;
    text-align: center;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.social-links {
    display: flex;
    gap: 1.5rem;
    margin: 2rem 0;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    transition: all 0.3s ease;
}

.social-links a:hover {
    color: var(--yellow);
}

.footer-nav {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 2rem;
}

.footer-nav a {
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.footer-nav a:hover {
    color: var(--yellow);
}

.copyright {
    font-size: 0.9rem;
    opacity: 0.8;
}

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

    .hero p {
        font-size: 1rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

.ukraine-heart {
    display: inline-block;
    font-size: 1.8rem;
    margin: 0 0.5rem;
    animation: beat 1.2s infinite alternate;
    color: var(--yellow);
}

@keyframes beat {
    to {
        transform: scale(1.2);
    }
}

.quote-section {
    font-style: italic;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    color: var(--blue);
    font-size: 1.2rem;
    position: relative;
}

.quote-section::before,
.quote-section::after {
    content: '"';
    font-size: 4rem;
    position: absolute;
    opacity: 0.2;
    font-family: Georgia, serif;
}

.quote-section::before {
    top: 0;
    left: 0;
}

.quote-section::after {
    bottom: -20px;
    right: 0;
    transform: rotate(180deg);
}

.flag-icon {
    width: 24px;
    height: 16px;
    vertical-align: middle;
    margin-right: 0.5rem;
}