:root {
    --bg-dark: #0f111a;
    --bg-surface: rgba(255, 255, 255, 0.03);
    --bg-surface-hover: rgba(255, 255, 255, 0.08);
    --border-light: rgba(255, 255, 255, 0.05);

    --text-main: #ffffff;
    --text-muted: #a0aec0;
    
    --primary-gradient: linear-gradient(135deg, #a855f7, #ec4899);
    --primary-glow: rgba(168, 85, 247, 0.4);
    
    --font-main: 'Inter', sans-serif;
    --border-radius-lg: 24px;
    --border-radius-md: 16px;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-main);
    font-size: 18px; 
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 4rem;
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(15, 17, 26, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-light);
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.6rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.logo-icon { 
    font-size: 1.9rem; 
    color: #a855f7; 
    -webkit-text-fill-color: initial; 
}

.search-bar {
    display: flex;
    align-items: center;
    background: var(--bg-surface);
    border: 1px solid var(--border-light);
    border-radius: 50px;
    padding: 0.85rem 1.5rem;
    width: 550px;
    transition: var(--transition);
}

.search-bar:focus-within {
    background: var(--bg-surface-hover);
    border-color: rgba(168, 85, 247, 0.4);
    box-shadow: 0 0 15px rgba(168, 85, 247, 0.15);
}

.search-bar i {
    color: var(--text-muted);
    font-size: 1.3rem;
    margin-right: 12px;
}

.search-bar input {
    background: transparent;
    border: none;
    color: var(--text-main);
    font-family: var(--font-main);
    font-size: 0.95rem;
    width: 100%;
    outline: none;
}

.search-bar input::placeholder {
    color: var(--text-muted);
}

.btn-ai-toggle {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 0.8rem 1.6rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
    box-shadow: 0 4px 15px var(--primary-glow);
    font-family: var(--font-main);
}

.btn-ai-toggle:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(236, 72, 153, 0.5);
}

.hero {
    padding: 6rem 4rem 4rem;
    text-align: center;
    position: relative;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.2rem;
    background: linear-gradient(to right, #ffffff, #a0aec0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 650px;
    margin: 0 auto;
}

.book-feed { 
    padding: 2rem 4rem 6rem; 
}

.section-title { 
    font-size: 2rem; 
    font-weight: 700; 
    margin-bottom: 2rem; 
}

.loading-state {
    text-align: center;
    color: #a855f7;
    margin-bottom: 2rem;
    font-size: 1.1rem;
    display: none;
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.book-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-light);
    border-radius: var(--border-radius-lg);
    padding: 1.5rem;
    transition: var(--transition);
    cursor: pointer;
    text-align: center;
}

.book-card:hover {
    background: var(--bg-surface-hover);
    transform: translateY(-8px);
    border-color: rgba(168, 85, 247, 0.3);
    box-shadow: 0 10px 30px rgba(168, 85, 247, 0.1);
}

.book-cover {
    width: 60%;
    aspect-ratio: 13/20;
    border-radius: 8px;
    object-fit: cover;
    margin: 0 auto 1.2rem;
    display: block;
    box-shadow: 0 10px 20px rgba(0,0,0,0.4);
    transition: transform 0.3s;
}

.book-card:hover .book-cover {
    transform: scale(1.05);
}

.book-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 0.6rem;
}

.book-author {
    font-size: 0.95rem;
    color: var(--text-muted);
}

.btn-open-reader {
    margin-top: 1.5rem;
    background: var(--bg-surface-hover);
    border: 1px solid rgba(168, 85, 247, 0.3);
    color: #e9d5ff;
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    width: 100%;
    transition: 0.3s;
    font-family: inherit;
    cursor: pointer;
}

.book-card:hover .btn-open-reader {
    background: rgba(168, 85, 247, 0.3);
    color: white;
}

.pagination-actions {
    text-align: center;
    margin-top: 3.5rem;
}

#btn-load-more {
    display: inline-flex;
    justify-content: center;
    width: auto;
    padding: 0.8rem 2.5rem;
    font-size: 1.1rem;
    border-color: rgba(168, 85, 247, 0.5);
}

.reader-modal-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(5, 6, 8, 0.98);
    backdrop-filter: blur(15px);
    z-index: 1000; 
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
    display: flex;
    justify-content: center;
    align-items: center;
}

.reader-modal-overlay.active {
    opacity: 1;
    pointer-events: all;
}

.reader-container {
    width: 95%;
    max-width: 1400px;
    height: 90vh;
    background: rgba(20, 23, 35, 0.9);
    border: 1px solid var(--border-light);
    border-radius: var(--border-radius-lg);
    box-shadow: 0 20px 60px rgba(0,0,0,0.8);
    position: relative;
    overflow: hidden;
    transform: translateY(20px) scale(0.98);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.reader-modal-overlay.active .reader-container {
    transform: translateY(0) scale(1);
}

.reader-close-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    background: rgba(236, 72, 153, 0.1);
    border: 1px solid rgba(236, 72, 153, 0.3);
    color: #fbcfe8;
    padding: 0.6rem 1.2rem;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    z-index: 10;
    transition: 0.3s;
    display: flex; 
    align-items: center; 
    gap: 5px;
    font-family: inherit;
}

.reader-close-btn:hover { 
    background: rgba(236, 72, 153, 0.4); 
    color: white; 
}

.reader-layout {
    display: flex;
    height: 100%;
}

.reader-sidebar {
    width: 300px;
    background: rgba(15, 17, 26, 0.5);
    border-right: 1px solid var(--border-light);
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.sidebar-cover {
    width: 120px;
    border-radius: 6px;
    align-self: center;
    margin-bottom: 1rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.5);
}

.sidebar-title {
    font-size: 1.2rem; 
    font-weight: 700; 
    text-align: center; 
    line-height: 1.3; 
    margin-bottom: 0.2rem;
}

.sidebar-author {
    font-size: 0.9rem; 
    color: var(--text-muted); 
    text-align: center; 
    margin-bottom: 2rem;
}

.sidebar-links {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
    margin-bottom: 2rem;
}

.sidebar-btn {
    text-decoration: none;
    padding: 0.8rem 1rem;
    border-radius: 12px;
    font-size: 0.95rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: var(--transition);
}

.btn-buy {
    background: rgba(236, 72, 153, 0.1);
    color: #fbcfe8;
    border: 1px solid rgba(236, 72, 153, 0.3);
}

.btn-buy:hover {
    background: #ec4899;
    color: white;
    box-shadow: 0 4px 15px rgba(236, 72, 153, 0.4);
}

.btn-audio {
    background: rgba(168, 85, 247, 0.1);
    color: #e9d5ff;
    border: 1px solid rgba(168, 85, 247, 0.3);
}

.btn-audio:hover {
    background: #a855f7;
    color: white;
    box-shadow: 0 4px 15px rgba(168, 85, 247, 0.4);
}

.sidebar-chapters {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.chapter-item {
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-muted);
    padding: 0.8rem 1rem;
    border-radius: 12px;
    text-align: left;
    font-size: 0.95rem;
    cursor: pointer;
    transition: 0.2s;
    font-family: inherit;
}

.chapter-item:hover { 
    background: var(--bg-surface-hover); 
    color: white; 
}

.chapter-item.active {
    background: rgba(168, 85, 247, 0.15);
    border-color: rgba(168, 85, 247, 0.4);
    color: #e9d5ff;
    font-weight: 600;
}

.reader-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: 3rem 5rem;
    position: relative;
    overflow-y: auto;
}

.content-header {
    border-bottom: 1px solid var(--border-light);
    padding-bottom: 2rem;
    margin-bottom: 3rem;
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
}

.content-header h2 {
    font-size: 2.2rem;
    font-weight: 700;
    max-width: 70%;
    color: white;
}

.content-actions { 
    display: flex; 
    gap: 10px; 
}

.btn-reader-action {
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    display: flex; 
    align-items: center; 
    gap: 8px;
    transition: 0.3s; 
    border: none; 
    font-family: inherit; 
    font-size: 1rem;
}

.play-action { 
    background: #a855f7; 
    color: white; 
    box-shadow: 0 4px 15px rgba(168, 85, 247, 0.4); 
}

.play-action:hover { 
    background: #9333ea; 
    transform: translateY(-2px); 
}

.pause-action { 
    background: #ec4899; 
    color: white; 
    box-shadow: 0 4px 15px rgba(236, 72, 153, 0.4); 
}

.pause-action:hover { 
    background: #db2777; 
    transform: translateY(-2px); 
}

.content-body {
    font-size: 1.3rem; 
    line-height: 1.8;
    color: #cbd5e1;
    max-width: 850px;
    margin: 0 auto;
    padding-bottom: 5rem;
}

.content-body p { 
    margin-bottom: 1.5rem; 
}

.tts-status {
    position: fixed; 
    top: 95px; 
    left: 50%; 
    transform: translateX(-50%);
    background: rgba(20, 23, 35, 0.95); 
    backdrop-filter: blur(10px);
    border: 1px solid rgba(168, 85, 247, 0.4); 
    padding: 0.8rem 1.5rem; 
    border-radius: 50px;
    z-index: 2000; 
    display: flex; 
    align-items: center; 
    gap: 1rem; 
    box-shadow: 0 10px 25px rgba(168, 85, 247, 0.2);
}

.tts-status.hidden { 
    display: none; 
}

.tts-status span { 
    font-size: 0.95rem; 
    color: #e9d5ff; 
    font-weight: 500; 
}

.tts-stop {
    background: rgba(236, 72, 153, 0.2); 
    color: #fbcfe8; 
    border: 1px solid transparent;
    border-radius: 20px; 
    padding: 0.3rem 0.8rem; 
    cursor: pointer; 
    transition: 0.2s;
    font-family: inherit;
}

.tts-stop:hover { 
    background: rgba(236, 72, 153, 0.5); 
    color: white; 
}

.wave { 
    display: flex; 
    align-items: center; 
    gap: 3px; 
    height: 15px; 
}

.wave .bar { 
    width: 3px; 
    background-color: #ec4899; 
    animation: wave-anim 1s ease-in-out infinite; 
    border-radius: 2px; 
}

.wave .bar:nth-child(1) { height: 6px; animation-delay: 0s; }
.wave .bar:nth-child(2) { height: 15px; animation-delay: -0.2s; }
.wave .bar:nth-child(3) { height: 10px; animation-delay: -0.4s; }

@keyframes wave-anim {
    0%, 100% { transform: scaleY(0.7); }
    50% { transform: scaleY(1.5); }
}

.ai-widget {
    position: fixed; 
    bottom: 30px; 
    right: 30px; 
    width: 360px;
    background: rgba(20, 23, 35, 0.95); 
    backdrop-filter: blur(15px);
    border: 1px solid var(--border-light); 
    border-radius: var(--border-radius-lg);
    box-shadow: 0 15px 40px rgba(0,0,0,0.4); 
    display: flex; 
    flex-direction: column;
    z-index: 2000; 
    transform: translateY(150%) scale(0.9); 
    opacity: 0; 
    transition: all 0.4s ease;
}

.ai-widget.open { 
    transform: translateY(0) scale(1); 
    opacity: 1; 
}

.ai-header { 
    display: flex; 
    justify-content: space-between; 
    padding: 1rem 1.5rem; 
    border-bottom: 1px solid var(--border-light); 
}

.ai-title { 
    font-weight: 600; 
    display: flex; 
    align-items: center; 
    gap: 0.5rem; 
    color: #e9d5ff; 
}

.close-ai-btn { 
    background: none; 
    border: none; 
    color: var(--text-muted); 
    cursor: pointer; 
    font-size: 1.2rem; 
}

.ai-body { 
    padding: 1.5rem; 
    max-height: 450px; 
    overflow-y: auto; 
    display: flex; 
    flex-direction: column; 
    gap: 1rem; 
}

.chat-message { 
    padding: 1rem; 
    border-radius: 16px; 
    font-size: 0.95rem; 
}

.ai-message { 
    background: rgba(168, 85, 247, 0.1); 
    border: 1px solid rgba(168, 85, 247, 0.2); 
    border-top-left-radius: 4px; 
}

.user-message { 
    background: var(--bg-surface-hover); 
    align-self: flex-end; 
    border-top-right-radius: 4px; 
    margin-left: 2rem; 
}

.mood-chips { 
    display: flex; 
    flex-wrap: wrap; 
    gap: 0.5rem; 
    margin-top: 0.5rem; 
}

.mood-chip {
    background: rgba(255, 255, 255, 0.05); 
    border: 1px solid var(--border-light); 
    color: var(--text-main);
    padding: 0.5rem 0.8rem; 
    border-radius: 50px; 
    cursor: pointer; 
    transition: 0.2s; 
    font-family: inherit;
}

.mood-chip:hover { 
    background: rgba(255, 255, 255, 0.1); 
}

.typing-indicator { 
    display: none; 
    align-items: center; 
    gap: 4px; 
    padding: 0.8rem 1rem; 
    background: rgba(168, 85, 247, 0.05); 
    border-radius: 16px; 
    width: fit-content; 
}

.typing-indicator span { 
    width: 6px; 
    height: 6px; 
    background: #a855f7; 
    border-radius: 50%; 
    animation: typing 1.4s infinite ease-in-out both; 
}

.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }

::-webkit-scrollbar { 
    width: 8px; 
}

::-webkit-scrollbar-track { 
    background: transparent; 
}

::-webkit-scrollbar-thumb { 
    background: rgba(255, 255, 255, 0.1); 
    border-radius: 10px; 
}

::-webkit-scrollbar-thumb:hover { 
    background: rgba(255, 255, 255, 0.3); 
}