:root {
    --bg: #060918;
    --bg2: #0a0d1d;
    --surface: rgba(15, 18, 37, 0.8);
    --surface-hover: rgba(20, 24, 50, 0.9);
    --border: rgba(255, 255, 255, 0.06);
    --border-hover: rgba(255, 255, 255, 0.12);
    --text: #e2e8f0;
    --text2: #94a3b8;
    --text3: #64748b;
    --primary: #6366f1;
    --primary-light: #818cf8;
    --primary-dark: #4f46e5;
    --secondary: #a855f7;
    --accent: #22d3ee;
    --gold: #f59e0b;
    --success: #10b981;
    --danger: #ef4444;
    --warn: #f59e0b;
    --radius: 16px;
    --radius-sm: 10px;
    --radius-xs: 8px;
    --shadow: 0 4px 24px rgba(0,0,0,0.3);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.5);
    --header-h: 64px;
    --transition: 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    --transition-slow: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -2;
    background:
        radial-gradient(ellipse 80% 60% at 50% -20%, rgba(99,102,241,0.12), transparent 60%),
        radial-gradient(ellipse 60% 50% at 85% 80%, rgba(168,85,247,0.08), transparent 60%),
        radial-gradient(ellipse 50% 40% at 15% 70%, rgba(34,211,238,0.05), transparent 60%);
}

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

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

::-webkit-scrollbar { width:6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius:3px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.2); }

::selection { background: rgba(99,102,241,0.4); color: #fff; }

/* ===== Header ===== */
.site-header {
    position: sticky; top:0; z-index:100;
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    background: rgba(6,9,24,0.75);
    border-bottom: 1px solid var(--border);
    height: var(--header-h);
    transition: all var(--transition);
}
.site-header.scrolled { background: rgba(6,9,24,0.9); box-shadow: 0 2px 20px rgba(0,0,0,0.3); }

.header-inner {
    max-width: 1280px; margin:0 auto; padding:0 24px;
    height:100%; display:flex; align-items:center; gap:24px;
}

.logo {
    font-size: 24px; font-weight: 800;
    background: linear-gradient(135deg, #6366f1, #a855f7, #ec4899);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
    white-space: nowrap;
    transition: transform var(--transition);
}
.logo:hover { transform: scale(1.05); }

.nav-links { display:flex; gap:4px; flex:1; }
.nav-links a {
    padding: 8px 16px; border-radius: 10px; font-size:14px; font-weight:500;
    color: var(--text2); transition: all var(--transition);
}
.nav-links a:hover, .nav-links a.active {
    color: var(--text); background: rgba(255,255,255,0.05);
}

.search-bar {
    position: relative; flex: 0 1 360px;
}
.search-bar input {
    width:100%; padding:10px 44px 10px 16px;
    background: rgba(255,255,255,0.04); border:1px solid var(--border); border-radius:24px;
    color: var(--text); font-size:14px; outline:none;
    transition: all var(--transition);
}
.search-bar input:focus {
    border-color: var(--primary); box-shadow: 0 0 0 3px rgba(99,102,241,0.1);
    background: rgba(255,255,255,0.06);
}
.search-bar input::placeholder { color: var(--text3); }
.search-bar .search-btn {
    position:absolute; right:4px; top:50%; transform:translateY(-50%);
    width:36px; height:36px; border-radius:50%; border:none;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color:#fff; cursor:pointer; font-size:16px;
    display:flex; align-items:center; justify-content:center;
    transition: all var(--transition);
}
.search-bar .search-btn:hover { transform:translateY(-50%) scale(1.08); }

.mobile-menu-btn {
    display:none; width:40px; height:40px; border-radius:10px; border:none;
    background: rgba(255,255,255,0.04); color:var(--text); cursor:pointer; font-size:20px;
    align-items:center; justify-content:center;
}

/* ===== Hero Section ===== */
.hero {
    max-width: 1280px; margin: 0 auto; padding: 60px 24px 40px;
    text-align: center; position:relative;
}
.hero-title {
    font-size: clamp(32px, 5vw, 56px); font-weight:900; line-height:1.15;
    background: linear-gradient(135deg, #e2e8f0 0%, #818cf8 40%, #a855f7 70%, #e2e8f0 100%);
    background-size: 200% auto;
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
    animation: gradientShift 4s ease-in-out infinite;
    margin-bottom: 16px;
}
@keyframes gradientShift {
    0%, 100% { background-position: 0% center; }
    50% { background-position: 100% center; }
}
.hero-subtitle {
    color: var(--text2); font-size: 18px; max-width:600px; margin:0 auto 32px;
    line-height:1.7;
}
.hero-stats {
    display:flex; gap:32px; justify-content:center; flex-wrap:wrap;
}
.hero-stat {
    text-align:center;
    animation: fadeUp 0.6s var(--ease-spring) both;
}
.hero-stat:nth-child(1) { animation-delay: 0.1s; }
.hero-stat:nth-child(2) { animation-delay: 0.2s; }
.hero-stat:nth-child(3) { animation-delay: 0.3s; }
.hero-stat .num {
    font-size:36px; font-weight:800;
    background: linear-gradient(135deg, var(--primary-light), var(--secondary));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.hero-stat .label { font-size:13px; color:var(--text3); margin-top:4px; }

@keyframes fadeUp {
    from { opacity:0; transform: translateY(24px); }
    to { opacity:1; transform: translateY(0); }
}

/* ===== Main Container ===== */
.main-container {
    max-width: 1280px; margin: 0 auto; padding: 0 24px 60px;
}

/* ===== Section Title ===== */
.section-header {
    display:flex; align-items:center; justify-content:space-between; margin-bottom: 24px;
}
.section-title {
    font-size:22px; font-weight:700;
    display:flex; align-items:center; gap:10px;
}
.section-title .icon { font-size:26px; }
.section-more {
    font-size:13px; color:var(--text3); padding:6px 14px; border-radius:20px;
    border:1px solid var(--border); transition: all var(--transition);
}
.section-more:hover { border-color:var(--primary); color:var(--primary-light); }

/* ===== Category Pills ===== */
.category-scroll {
    display:flex; gap:10px; overflow-x:auto; padding-bottom:8px; margin-bottom:32px;
    scrollbar-width: none; -ms-overflow-style: none;
}
.category-scroll::-webkit-scrollbar { display:none; }
.cat-pill {
    display:flex; align-items:center; gap:6px;
    padding:8px 18px; border-radius:24px; border:1px solid var(--border);
    background: var(--surface); color:var(--text2); font-size:13px; font-weight:500;
    white-space:nowrap; cursor:pointer; user-select:none;
    transition: all var(--transition);
    backdrop-filter: blur(10px);
}
.cat-pill:hover { border-color: var(--primary); color: var(--text); background: rgba(99,102,241,0.1); }
.cat-pill.active {
    border-color: var(--primary); color: #fff;
    background: linear-gradient(135deg, rgba(99,102,241,0.25), rgba(168,85,247,0.2));
    box-shadow: 0 2px 12px rgba(99,102,241,0.2);
}
.cat-pill .emoji { font-size:16px; }

/* ===== Book Grid ===== */
.book-grid {
    display:grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap:20px;
}

.book-card {
    position:relative;
    background: var(--surface);
    border:1px solid var(--border);
    border-radius: var(--radius);
    overflow:hidden;
    cursor:pointer;
    transition: all var(--transition-slow);
    backdrop-filter: blur(12px);
    animation: fadeUp 0.5s var(--ease-spring) both;
}
.book-card:hover {
    transform: translateY(-6px);
    border-color: var(--border-hover);
    box-shadow: 0 12px 40px rgba(99,102,241,0.1), 0 4px 12px rgba(0,0,0,0.3);
}
.book-card:active { transform: scale(0.98); }

.book-cover {
    position:relative; aspect-ratio: 3/4; overflow:hidden;
    background: linear-gradient(135deg, #1a1d35, #151830);
}
.book-cover img {
    width:100%; height:100%; object-fit:cover;
    transition: transform 0.5s var(--ease-out-expo);
}
.book-card:hover .book-cover img { transform: scale(1.08); }

.book-cover .cover-overlay {
    position:absolute; inset:0; opacity:0;
    background: linear-gradient(to top, rgba(0,0,0,0.7) 0%, transparent 60%);
    transition: opacity var(--transition);
    display:flex; align-items:flex-end; padding:16px;
}
.book-card:hover .cover-overlay { opacity:1; }

.book-overlay-actions {
    display:flex; gap:8px; width:100%; justify-content:center;
    transform: translateY(10px); transition: transform var(--transition);
}
.book-card:hover .book-overlay-actions { transform: translateY(0); }

.book-overlay-btn {
    padding:8px 16px; border-radius:20px; border:none;
    font-size:12px; font-weight:600; cursor:pointer;
    backdrop-filter: blur(10px);
    transition: all var(--transition);
}
.book-overlay-btn.read {
    background: rgba(255,255,255,0.95); color: #1e1b4b;
}
.book-overlay-btn.download {
    background: rgba(99,102,241,0.9); color: #fff;
}
.book-overlay-btn:hover { transform: scale(1.08); }

.book-format-badge {
    position:absolute; top:10px; right:10px;
    padding:3px 10px; border-radius:12px; font-size:11px; font-weight:700;
    text-transform: uppercase;
    background: rgba(0,0,0,0.5); backdrop-filter: blur(8px);
    color: rgba(255,255,255,0.9); letter-spacing: 0.5px;
}

.book-info { padding:14px 16px; }
.book-title {
    font-size:14px; font-weight:600; line-height:1.4;
    display: -webkit-box; -webkit-line-clamp:2; -webkit-box-orient:vertical;
    overflow:hidden; margin-bottom:6px;
}
.book-author {
    font-size:12px; color:var(--text3);
    display:flex; align-items:center; gap:4px;
}

.book-meta {
    display:flex; align-items:center; gap:12px; margin-top:8px; font-size:11px; color:var(--text3);
}
.book-meta span { display:flex; align-items:center; gap:3px; }

/* ===== Book Detail Modal ===== */
.modal-overlay {
    position:fixed; inset:0; z-index:200; display:flex; align-items:center; justify-content:center;
    background: rgba(0,0,0,0.6); backdrop-filter: blur(8px);
    opacity:0; visibility:hidden; transition: all 0.3s var(--ease-smooth);
    padding: 20px;
}
.modal-overlay.active { opacity:1; visibility:visible; }
.modal-content {
    background: var(--surface); border:1px solid var(--border); border-radius:20px;
    max-width:700px; width:100%; max-height:85vh; overflow-y:auto;
    transform: scale(0.9) translateY(20px);
    transition: transform 0.4s var(--ease-spring);
    backdrop-filter: blur(30px);
}
.modal-overlay.active .modal-content { transform: scale(1) translateY(0); }

.modal-close {
    position:absolute; top:16px; right:16px; width:36px; height:36px;
    border-radius:50%; border:none; background:rgba(255,255,255,0.08);
    color:var(--text); font-size:18px; cursor:pointer;
    transition: all var(--transition); z-index:10;
}
.modal-close:hover { background:rgba(239,68,68,0.3); }

.modal-book-layout { display:flex; gap:24px; padding:28px; }
.modal-cover { width:180px; flex-shrink:0; border-radius:12px; overflow:hidden; box-shadow:var(--shadow-lg); }
.modal-cover img { width:100%; aspect-ratio:3/4; object-fit:cover; }
.modal-info { flex:1; }
.modal-info h2 { font-size:24px; font-weight:700; margin-bottom:8px; }
.modal-info .author { color:var(--text2); margin-bottom:16px; }
.modal-info .desc { color:var(--text2); font-size:14px; line-height:1.8; margin-bottom:20px; }
.modal-meta-grid {
    display:grid; grid-template-columns: 1fr 1fr; gap:10px; margin-bottom:20px;
}
.modal-meta-item { font-size:13px; color:var(--text3); }
.modal-meta-item strong { color:var(--text2); display:block; font-size:11px; text-transform:uppercase; letter-spacing:0.5px; margin-bottom:3px; }
.modal-actions { display:flex; gap:10px; flex-wrap:wrap; }

.btn {
    display:inline-flex; align-items:center; gap:6px; padding:10px 22px;
    border:none; border-radius:24px; font-size:14px; font-weight:600; cursor:pointer;
    transition: all var(--transition); text-decoration:none; font-family:inherit;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color:#fff; box-shadow: 0 4px 16px rgba(99,102,241,0.3);
}
.btn-primary:hover { transform:translateY(-2px); box-shadow: 0 8px 24px rgba(99,102,241,0.5); }
.btn-outline {
    background:transparent; border:1px solid var(--border); color:var(--text);
}
.btn-outline:hover { border-color:var(--primary); color:var(--primary-light); }
.btn-sm { padding:6px 14px; font-size:12px; }
.btn-danger { background:var(--danger); color:#fff; }

/* ===== Pagination ===== */
.pagination {
    display:flex; justify-content:center; gap:8px; margin-top:40px;
}
.pagination a, .pagination span {
    width:38px; height:38px; display:flex; align-items:center; justify-content:center;
    border-radius:10px; border:1px solid var(--border); font-size:14px; font-weight:500;
    transition: all var(--transition);
    background: var(--surface); color: var(--text2);
}
.pagination a:hover { border-color:var(--primary); color:var(--primary-light); }
.pagination .current { border-color:var(--primary); background:rgba(99,102,241,0.15); color:var(--primary-light); }

/* ===== Empty State ===== */
.empty-state { text-align:center; padding:60px 20px; }
.empty-state .icon { font-size:64px; margin-bottom:16px; animation: float 3s ease-in-out infinite; }
@keyframes float {
    0%, 100% { transform:translateY(0); }
    50% { transform:translateY(-10px); }
}
.empty-state h3 { font-size:20px; margin-bottom:8px; }
.empty-state p { color:var(--text3); }

/* ===== Breadcrumb ===== */
.breadcrumb {
    display:flex; gap:6px; align-items:center; font-size:13px; color:var(--text3); margin-bottom:24px; flex-wrap:wrap;
}
.breadcrumb a { color:var(--text3); }
.breadcrumb a:hover { color:var(--primary-light); }
.breadcrumb .sep { color:var(--text3); }

/* ===== Skeleton Loading ===== */
.skeleton {
    background: linear-gradient(90deg, rgba(255,255,255,0.03) 25%, rgba(255,255,255,0.06) 50%, rgba(255,255,255,0.03) 75%);
    background-size: 200% 100%;
    animation: skeletonPulse 1.5s ease-in-out infinite;
    border-radius: var(--radius-xs);
}
@keyframes skeletonPulse {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* ===== Toast ===== */
.toast-container { position:fixed; top:80px; right:20px; z-index:300; display:flex; flex-direction:column; gap:8px; }
.toast {
    padding:12px 20px; border-radius:12px; font-size:14px; font-weight:500;
    backdrop-filter: blur(20px); border:1px solid var(--border);
    animation: toastIn 0.4s var(--ease-spring);
    display:flex; align-items:center; gap:8px;
}
.toast.success { background:rgba(16,185,129,0.15); border-color:rgba(16,185,129,0.3); color:#6ee7b7; }
.toast.error { background:rgba(239,68,68,0.15); border-color:rgba(239,68,68,0.3); color:#fca5a5; }
.toast.info { background:rgba(99,102,241,0.15); border-color:rgba(99,102,241,0.3); color:#a5b4fc; }
@keyframes toastIn { from { opacity:0; transform: translateX(40px); } to { opacity:1; transform: translateX(0); } }

/* ===== Footer ===== */
.site-footer {
    text-align:center; padding:32px 24px; border-top:1px solid var(--border);
    color:var(--text3); font-size:13px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .nav-links { display:none; }
    .nav-links.open {
        display:flex; flex-direction:column; position:absolute; top:var(--header-h);
        left:0; right:0; background:rgba(6,9,24,0.95); backdrop-filter:blur(30px);
        padding:16px; border-bottom:1px solid var(--border); z-index:99;
    }
    .mobile-menu-btn { display:flex; }
    .search-bar { flex:1; }
    .book-grid { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap:14px; }
    .modal-book-layout { flex-direction:column; }
    .modal-cover { width:140px; margin:0 auto; }
    .hero-stats { gap:20px; }
    .hero-stat .num { font-size:28px; }
}

@media (max-width: 480px) {
    .header-inner { padding:0 12px; gap:12px; }
    .book-grid { grid-template-columns: repeat(2, 1fr); gap:10px; }
    .book-info { padding:10px 12px; }
    .book-title { font-size:13px; }
}

/* ===== Scroll Animations ===== */
.animate-on-scroll {
    opacity: 0; transform: translateY(30px);
    transition: opacity 0.6s var(--ease-out-expo), transform 0.6s var(--ease-out-expo);
}
.animate-on-scroll.visible { opacity: 1; transform: translateY(0); }

/* ===== Star Particles ===== */
#particles-canvas {
    position:fixed; inset:0; z-index:-1; pointer-events:none;
}