@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800;900&display=swap');

:root {
    /* Base Color Tokens (Modern Indigo/Violet theme) */
    --primary-hue: 239;
    --primary: hsl(var(--primary-hue), 84%, 67%); /* Modern Indigo */
    --primary-dark: hsl(var(--primary-hue), 84%, 57%);
    --primary-light: hsl(var(--primary-hue), 100%, 96%);
    --primary-glow: rgba(99, 102, 241, 0.25);
    
    --success: #10b981;
    --danger: #f43f5e;
    --warning: #f59e0b;
    --info: #06b6d4;
    
    /* Design Tokens - Default Light Mode */
    --bg: #f8fafc;
    --surface: #ffffff;
    --surface-glass: rgba(255, 255, 255, 0.75);
    --surface-glass-hover: rgba(255, 255, 255, 0.9);
    --border: rgba(226, 232, 240, 0.8);
    --border-focus: hsl(var(--primary-hue), 84%, 75%);
    --text: #0f172a;
    --text-muted: #64748b;
    
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow: 0 4px 16px rgba(99, 102, 241, 0.05), 0 2px 4px rgba(0, 0, 0, 0.02);
    --shadow-md: 0 10px 24px rgba(99, 102, 241, 0.08), 0 4px 8px rgba(0, 0, 0, 0.03);
    --shadow-lg: 0 20px 40px rgba(99, 102, 241, 0.12), 0 8px 16px rgba(0, 0, 0, 0.04);
    
    --radius: 18px;
    --radius-sm: 12px;
    --radius-lg: 24px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode Tokens */
[data-theme="dark"] {
    --bg: #090d16;
    --surface: #111827;
    --surface-glass: rgba(17, 24, 39, 0.75);
    --surface-glass-hover: rgba(24, 32, 51, 0.85);
    --border: rgba(30, 41, 59, 0.7);
    --border-focus: hsl(var(--primary-hue), 84%, 67%);
    --text: #f8fafc;
    --text-muted: #94a3b8;
    
    --primary-light: hsl(var(--primary-hue), 30%, 15%);
    --primary-glow: rgba(99, 102, 241, 0.4);
    
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow: 0 4px 16px rgba(0, 0, 0, 0.25), 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 10px 24px rgba(0, 0, 0, 0.3), 0 4px 8px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.4), 0 8px 16px rgba(0, 0, 0, 0.2);
}

/* Global Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Outfit', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background 0.4s ease, color 0.4s ease, border-color 0.4s ease;
}

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

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}
::-webkit-scrollbar-track {
    background: var(--bg);
}
::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 99px;
    border: 3px solid var(--bg);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Theme Switcher Button Style */
.theme-toggle-btn {
    border: none;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    color: var(--text);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
    backdrop-filter: blur(8px);
}
.theme-toggle-btn:hover {
    transform: rotate(30deg) scale(1.1);
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 0 12px var(--primary-glow);
}

/* ---- NAVBAR ---- */
.navbar {
    background: var(--surface-glass);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}
.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.4rem;
    color: var(--primary);
    letter-spacing: -0.5px;
}
.nav-logo i {
    font-size: 1.5rem;
    filter: drop-shadow(0 2px 8px var(--primary-glow));
    animation: pulseLogo 3s infinite;
}
@keyframes pulseLogo {
    0%, 100% { transform: scale(1); filter: drop-shadow(0 2px 8px var(--primary-glow)); }
    50% { transform: scale(1.08); filter: drop-shadow(0 4px 14px var(--primary)); }
}
.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
    align-items: center;
}
.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-muted);
    position: relative;
    padding: 6px 0;
}
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    border-radius: 99px;
}
.nav-links a:hover {
    color: var(--text);
}
.nav-links a:hover::after, .nav-links a.active::after {
    width: 100%;
}
.nav-links a.active {
    color: var(--primary);
    font-weight: 600;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

/* ---- BUTTONS ---- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 22px;
    border-radius: var(--radius-sm);
    font-size: .9rem;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid transparent;
    transition: var(--transition);
    font-family: inherit;
    box-shadow: var(--shadow-sm);
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: #fff;
    border: none;
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}
.btn-primary:active {
    transform: translateY(0);
}
.btn-outline {
    background: var(--surface-glass);
    border: 1px solid var(--border);
    color: var(--text);
}
.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 4px 12px var(--primary-glow);
    transform: translateY(-1px);
}
.btn-danger {
    background: linear-gradient(135deg, var(--danger) 0%, #be123c 100%);
    color: #fff;
    border: none;
}
.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(244, 63, 94, 0.35);
}
.btn-success {
    background: linear-gradient(135deg, var(--success) 0%, #047857 100%);
    color: #fff;
    border: none;
}
.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.35);
}

/* ---- HERO ---- */
.hero {
    background: radial-gradient(circle at 10% 20%, var(--primary-light) 0%, transparent 60%),
                radial-gradient(circle at 90% 80%, rgba(168, 85, 247, 0.08) 0%, transparent 60%);
    padding: 90px 0 70px;
    position: relative;
    overflow: hidden;
}
.hero-inner {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 48px;
    align-items: center;
    position: relative;
    z-index: 2;
}
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--primary-light);
    border: 1px solid rgba(99, 102, 241, 0.2);
    color: var(--primary);
    padding: 6px 16px;
    border-radius: 99px;
    font-size: .82rem;
    font-weight: 700;
    margin-bottom: 20px;
    box-shadow: var(--shadow-sm);
    letter-spacing: 0.5px;
    text-transform: uppercase;
}
.hero h1 {
    font-size: 3.4rem;
    font-weight: 900;
    line-height: 1.15;
    letter-spacing: -1.5px;
}
.hero h1 span {
    background: linear-gradient(135deg, var(--primary) 20%, #a855f7 80%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero p {
    color: var(--text-muted);
    margin: 20px 0 32px;
    font-size: 1.1rem;
    max-width: 540px;
}
.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}
.hero-actions .btn {
    padding: 12px 28px;
    border-radius: var(--radius-sm);
}

/* Floating 3D Graphic container */
.hero-img {
    border-radius: var(--radius-lg);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    min-height: 340px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    backdrop-filter: blur(16px);
    overflow: visible;
}
.hero-img::before {
    content: '';
    position: absolute;
    width: 240px;
    height: 240px;
    background: radial-gradient(circle, var(--primary) 0%, transparent 70%);
    opacity: 0.18;
    filter: blur(20px);
    z-index: 1;
    animation: pulseGlow 6s infinite ease-in-out;
}
@keyframes pulseGlow {
    0%, 100% { transform: scale(1); opacity: 0.15; }
    50% { transform: scale(1.2); opacity: 0.25; }
}

/* Abstract floating shapes for premium look */
.hero-img i.fa-graduation-cap {
    font-size: 7.5rem;
    background: linear-gradient(135deg, var(--primary) 0%, #a855f7 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 8px 16px var(--primary-glow));
    z-index: 2;
    animation: floatCap 4s infinite ease-in-out;
}
@keyframes floatCap {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-15px) rotate(-3deg); }
}

/* Layered glass cards floating */
.hero-img::after {
    content: '📄 Tài liệu thi';
    position: absolute;
    top: 40px;
    left: -20px;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    padding: 10px 18px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 600;
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(12px);
    z-index: 3;
    animation: floatPlate 5s infinite ease-in-out;
}
.floating-glass-plate-2 {
    position: absolute;
    bottom: 50px;
    right: -15px;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    padding: 10px 18px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 600;
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(12px);
    z-index: 3;
    animation: floatPlate 6s infinite ease-in-out reverse;
}
@keyframes floatPlate {
    0%, 100% { transform: translateY(0) translateX(0); }
    50% { transform: translateY(-12px) translateX(6px); }
}

.hero-stats {
    display: flex;
    gap: 36px;
    margin-top: 36px;
    border-top: 1px solid var(--border);
    padding-top: 24px;
}
.stat-item {
    text-align: left;
}
.stat-num {
    font-size: 1.8rem;
    font-weight: 900;
    color: var(--primary);
    letter-spacing: -0.5px;
}
.stat-label {
    font-size: .85rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* ---- FEATURED SCROLL ---- */
.featured-section {
    background: linear-gradient(90deg, var(--primary) 0%, #7c3aed 100%);
    padding: 18px 0;
    overflow: hidden;
    position: relative;
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.15);
}
.featured-label {
    color: rgba(255, 255, 255, 0.9);
    font-size: .8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.scroll-track {
    overflow: hidden;
    position: relative;
    /* Soft fade mask on both edges */
    -webkit-mask-image: linear-gradient(to right, transparent 0%, black 10%, black 90%, transparent 100%);
    mask-image: linear-gradient(to right, transparent 0%, black 10%, black 90%, transparent 100%);
}
.scroll-track-inner {
    display: flex;
    gap: 16px;
    white-space: nowrap;
    animation: scrollX 30s linear infinite;
}
.scroll-track:hover .scroll-track-inner {
    animation-play-state: paused;
}
@keyframes scrollX {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}
.scroll-tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: #fff;
    padding: 8px 18px;
    border-radius: 99px;
    font-size: .85rem;
    font-weight: 500;
    white-space: nowrap;
    cursor: pointer;
    transition: var(--transition);
    backdrop-filter: blur(8px);
}
.scroll-tag:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

/* ---- SEARCH SECTION ---- */
.search-section {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 30px 0;
    position: relative;
    z-index: 10;
}
.search-wrap {
    display: flex;
    gap: 14px;
    align-items: center;
    flex-wrap: wrap;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    padding: 12px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    backdrop-filter: blur(8px);
}
.search-box {
    flex: 2;
    min-width: 260px;
    position: relative;
}
.search-box i {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-size: 1rem;
}
.search-box input {
    width: 100%;
    padding: 12px 16px 12px 46px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: .95rem;
    transition: var(--transition);
}
.search-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-glow);
}
.filter-select {
    flex: 1;
    min-width: 160px;
    padding: 12px 16px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: .9rem;
    cursor: pointer;
    transition: var(--transition);
}
.filter-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-glow);
}

/* ---- MAIN SECTION ---- */
.main-section {
    padding: 50px 0 80px;
}
.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 32px;
}
.section-title {
    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    position: relative;
    padding-left: 14px;
}
.section-title::before {
    content: '';
    position: absolute;
    left: 0;
    top: 15%;
    width: 4px;
    height: 70%;
    background: var(--primary);
    border-radius: 99px;
}
.results-count {
    font-size: .9rem;
    color: var(--text-muted);
    font-weight: 500;
    background: var(--primary-light);
    color: var(--primary);
    padding: 4px 12px;
    border-radius: 99px;
}

/* ---- DOCUMENT CARDS ---- */
.docs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
}
.doc-card {
    background: var(--surface-glass);
    backdrop-filter: blur(12px);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    padding: 24px;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow);
}
.doc-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary) 0%, #a855f7 100%);
    opacity: 0;
    transition: var(--transition);
}
.doc-card:hover {
    border-color: var(--border-focus);
    box-shadow: var(--shadow-lg);
    transform: translateY(-6px);
}
.doc-card:hover::after {
    opacity: 1;
}
.card-top {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    margin-bottom: 16px;
}
.file-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}
.icon-pdf {
    background: rgba(244, 63, 94, 0.12);
    color: var(--danger);
}
.icon-docx {
    background: rgba(59, 130, 246, 0.12);
    color: #2563eb;
}
.icon-pptx {
    background: rgba(245, 158, 11, 0.12);
    color: var(--warning);
}
.icon-xlsx {
    background: rgba(16, 185, 129, 0.12);
    color: var(--success);
}
.icon-default {
    background: rgba(100, 116, 139, 0.12);
    color: var(--secondary);
}

.doc-card:hover .file-icon {
    transform: scale(1.08) rotate(-5deg);
}

.card-meta {
    flex: 1;
    min-width: 0;
}
.card-title {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    letter-spacing: -0.2px;
}
.card-subject {
    font-size: .82rem;
    color: var(--primary);
    font-weight: 600;
    margin-top: 3px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.card-desc {
    font-size: .88rem;
    color: var(--text-muted);
    margin-bottom: 18px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    min-height: 44px;
}
.card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-top: 1px solid var(--border);
    padding-top: 14px;
}
.card-stats {
    display: flex;
    gap: 14px;
    align-items: center;
}
.stat {
    font-size: .8rem;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 4px;
}
.badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 99px;
    font-size: .75rem;
    font-weight: 700;
    letter-spacing: 0.5px;
}
.badge-pdf {
    background: rgba(244, 63, 94, 0.12);
    color: var(--danger);
}
.badge-docx {
    background: rgba(59, 130, 246, 0.12);
    color: #2563eb;
}
.badge-pptx {
    background: rgba(245, 158, 11, 0.12);
    color: var(--warning);
}
.badge-default {
    background: rgba(100, 116, 139, 0.12);
    color: var(--secondary);
}
.stars {
    font-size: .8rem;
    display: flex;
    gap: 2px;
}
.star-on {
    color: var(--warning);
}
.star-off {
    color: var(--border);
}

/* ---- SKELETON ---- */
.skeleton-card {
    background: var(--surface);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    padding: 24px;
}
.sk {
    background: linear-gradient(90deg, var(--border) 25%, var(--bg) 50%, var(--border) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite linear;
    border-radius: var(--radius-sm);
}
.sk-icon {
    width: 52px;
    height: 52px;
    margin-bottom: 16px;
}
.sk-title {
    height: 16px;
    width: 75%;
    margin-bottom: 12px;
}
.sk-line {
    height: 12px;
    width: 100%;
    margin-bottom: 8px;
}
.sk-line.short {
    width: 55%;
}
.sk-foot {
    height: 12px;
    width: 40%;
    margin-top: 18px;
    border-radius: 99px;
}
@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* ---- MODAL ---- */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(9, 13, 22, 0.6);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 500;
    align-items: center;
    justify-content: center;
    padding: 20px;
    opacity: 0;
    transition: opacity 0.3s ease;
}
.modal-overlay.active {
    display: flex;
    opacity: 1;
}
.modal-box {
    background: var(--surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    width: 100%;
    max-width: 640px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    transform: scale(0.9) translateY(20px);
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.modal-overlay.active .modal-box {
    transform: scale(1) translateY(0);
}
.modal-header {
    padding: 22px 28px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    background: var(--surface);
    z-index: 10;
}
.modal-title {
    font-size: 1.15rem;
    font-weight: 800;
    letter-spacing: -0.2px;
}
.modal-close {
    background: var(--bg);
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-muted);
    width: 34px;
    height: 34px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}
.modal-close:hover {
    background: var(--primary-light);
    color: var(--primary);
    transform: rotate(90deg);
}
.modal-body {
    padding: 28px;
}
.modal-footer {
    padding: 18px 28px;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 12px;
    justify-content: flex-end;
    background: var(--bg);
    border-bottom-left-radius: var(--radius-lg);
    border-bottom-right-radius: var(--radius-lg);
}

.detail-icon {
    width: 72px;
    height: 72px;
    border-radius: var(--radius-sm);
    font-size: 2.2rem;
    margin-bottom: 20px;
}
.detail-title {
    font-size: 1.35rem;
    font-weight: 800;
    margin-bottom: 6px;
    line-height: 1.3;
}
.detail-meta {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
    gap: 12px;
    margin: 20px 0;
    padding: 18px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
}
.dmeta-item {
    display: flex;
    flex-direction: column;
    gap: 3px;
}
.meta-label {
    font-size: .7rem;
    color: var(--text-muted);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.8px;
}
.meta-val {
    font-size: .9rem;
    font-weight: 600;
}
.detail-desc {
    font-size: .95rem;
    color: var(--text-muted);
    line-height: 1.7;
    margin-top: 14px;
}

/* Dynamic glowing button in modal */
#modal-download {
    position: relative;
    overflow: hidden;
}
#modal-download::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -60%;
    width: 20%;
    height: 200%;
    background: rgba(255, 255, 255, 0.25);
    transform: rotate(30deg);
    transition: 0.8s;
    animation: buttonLight 3s infinite;
}
@keyframes buttonLight {
    0% { left: -60%; }
    100% { left: 140%; }
}

/* ---- EMPTY STATE ---- */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}
.empty-state i {
    font-size: 3rem;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--text-muted) 0%, var(--border) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    opacity: 0.7;
    display: block;
}
.empty-state h3 {
    font-size: 1.1rem;
    margin-bottom: 6px;
    color: var(--text);
    font-weight: 700;
}

/* ---- PAGINATION ---- */
.pagination {
    display: flex;
    gap: 8px;
    justify-content: center;
    margin-top: 40px;
    flex-wrap: wrap;
}
.pg-btn {
    padding: 10px 16px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: .9rem;
    font-weight: 600;
    transition: var(--transition);
    min-width: 42px;
    font-family: inherit;
    box-shadow: var(--shadow-sm);
}
.pg-btn:hover:not([disabled]) {
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-1px);
}
.pg-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
    box-shadow: 0 4px 12px var(--primary-glow);
}
.pg-btn[disabled] {
    opacity: .35;
    cursor: not-allowed;
}
.pg-dots {
    padding: 10px 4px;
    color: var(--text-muted);
    font-weight: 600;
}

/* ---- TOAST ---- */
#toast-wrap {
    position: fixed;
    bottom: 24px;
    right: 24px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.toast-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 22px;
    border-radius: var(--radius-sm);
    background: var(--surface-glass);
    backdrop-filter: blur(12px);
    box-shadow: var(--shadow-lg);
    font-size: .9rem;
    font-weight: 600;
    cursor: pointer;
    min-width: 260px;
    border-left: 4px solid;
    animation: slideUp 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    border-top: 1px solid var(--border);
    border-right: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}
.toast-success {
    border-left-color: var(--success);
    color: var(--success);
}
.toast-error {
    border-left-color: var(--danger);
    color: var(--danger);
}
.toast-info {
    border-left-color: var(--primary);
    color: var(--primary);
}
.toast-warning {
    border-left-color: var(--warning);
    color: var(--warning);
}
@keyframes slideUp {
    from { transform: translateY(30px) scale(0.9); opacity: 0; }
    to { transform: translateY(0) scale(1); opacity: 1; }
}

/* ---- FOOTER ---- */
footer {
    background: #0b0f19;
    color: #64748b;
    padding: 60px 0 0;
    margin-top: 80px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 48px;
    padding-bottom: 48px;
}
.footer-brand {
    color: #fff;
    font-size: 1.3rem;
    font-weight: 800;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.footer-brand i {
    color: var(--primary);
}
.footer-desc {
    font-size: .9rem;
    line-height: 1.7;
    max-width: 380px;
}
.footer-heading {
    color: #fff;
    font-weight: 700;
    margin-bottom: 16px;
    font-size: 1rem;
}
.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.footer-links a {
    font-size: .9rem;
    color: #94a3b8;
}
.footer-links a:hover {
    color: var(--primary);
    transform: translateX(3px);
}
.footer-links i {
    margin-right: 6px;
    font-size: 0.8rem;
}
.footer-bottom {
    text-align: center;
    padding: 20px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    font-size: .85rem;
}

/* ==========================================================================
   ADMIN LAYOUT & DASHBOARD STYLE
   ========================================================================== */
.admin-layout {
    display: flex;
    min-height: 100vh;
}

/* Sidebar Modern Glassmorphic Look */
.sidebar {
    width: 260px;
    background: #0b0f19;
    color: #94a3b8;
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    z-index: 200;
    transition: var(--transition);
    border-right: 1px solid rgba(255, 255, 255, 0.05);
}
.sidebar-logo {
    padding: 24px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: #fff;
    font-weight: 800;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 10px;
}
.sidebar-logo i {
    color: var(--primary);
    filter: drop-shadow(0 0 8px var(--primary));
}
.sidebar-nav {
    flex: 1;
    padding: 16px 12px;
    overflow-y: auto;
}
.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 18px;
    border-radius: var(--radius-sm);
    font-size: .95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    color: #94a3b8;
    border: none;
    background: none;
    width: 100%;
    text-align: left;
    font-family: inherit;
    margin-bottom: 6px;
}
.nav-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: #fff;
}
.nav-item.active {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: #fff;
    box-shadow: 0 4px 14px var(--primary-glow);
}
.nav-item i {
    width: 18px;
    text-align: center;
}
.sidebar-footer {
    padding: 20px 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.user-info {
    display: flex;
    align-items: center;
    gap: 12px;
}
.user-avatar {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary) 0%, #a855f7 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
    font-size: .95rem;
    box-shadow: 0 0 10px var(--primary-glow);
}
.user-name {
    font-size: .9rem;
    color: #e2e8f0;
    font-weight: 600;
}

/* Admin Main Core */
.admin-main {
    margin-left: 260px;
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: var(--transition);
}
.admin-header {
    background: var(--surface-glass);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    padding: 0 32px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}
.admin-header h2 {
    font-size: 1.3rem;
    font-weight: 800;
    letter-spacing: -0.3px;
}
.admin-content {
    padding: 32px;
    flex: 1;
}

/* Page states */
.admin-page {
    display: none;
    animation: fadeIn 0.4s ease;
}
.admin-page.active {
    display: block;
}

/* Dashboard Premium Widgets */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}
.stat-card {
    background: var(--surface-glass);
    backdrop-filter: blur(8px);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    padding: 24px;
    display: flex;
    align-items: center;
    gap: 18px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}
.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--border-focus);
}
.stat-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
}
.stat-icon.blue {
    background: rgba(99, 102, 241, 0.12);
    color: var(--primary);
}
.stat-icon.green {
    background: rgba(16, 185, 129, 0.12);
    color: var(--success);
}
.stat-icon.orange {
    background: rgba(245, 158, 11, 0.12);
    color: var(--warning);
}
.stat-icon.purple {
    background: rgba(168, 85, 247, 0.12);
    color: #9333ea;
}
.stat-info .label {
    font-size: .82rem;
    color: var(--text-muted);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.stat-info .value {
    font-size: 1.7rem;
    font-weight: 800;
    color: var(--text);
    line-height: 1.2;
    margin-top: 2px;
}

/* Recent Documents list in dashboard */
.dash-card {
    background: var(--surface);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    padding: 28px;
    box-shadow: var(--shadow);
}
.dash-card-title {
    margin-bottom: 20px;
    font-size: 1.15rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Elegant Table */
.table-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 14px;
}
.table-wrap {
    background: var(--surface);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow: auto;
    box-shadow: var(--shadow);
}
table {
    width: 100%;
    border-collapse: collapse;
    font-size: .92rem;
}
thead th {
    background: var(--bg);
    padding: 14px 20px;
    text-align: left;
    font-weight: 700;
    font-size: .78rem;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--text-muted);
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}
tbody td {
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    vertical-align: middle;
    color: var(--text);
}
tbody tr:last-child td {
    border-bottom: none;
}
tbody tr {
    transition: var(--transition);
}
tbody tr:hover {
    background: var(--primary-light);
}

.tbl-title {
    font-weight: 600;
    max-width: 240px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.tbl-actions {
    display: flex;
    gap: 8px;
}

/* Circle Action Buttons */
.btn-icon {
    width: 34px;
    height: 34px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-muted);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: .85rem;
    transition: var(--transition);
}
.btn-icon:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 0 8px var(--primary-glow);
    transform: scale(1.05);
}
.btn-icon.del:hover {
    border-color: var(--danger);
    color: var(--danger);
    box-shadow: 0 0 8px rgba(244, 63, 94, 0.2);
}

/* Dot glowing status */
.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}
.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: inline-block;
}
.status-dot.active {
    background-color: var(--success);
    box-shadow: 0 0 8px var(--success);
    animation: pulseDot 2s infinite;
}
.status-dot.inactive {
    background-color: var(--text-muted);
}
@keyframes pulseDot {
    0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
    70% { box-shadow: 0 0 0 6px rgba(16, 185, 129, 0); }
    100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

/* Premium Admin Form */
.form-card {
    background: var(--surface);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    padding: 32px;
    max-width: 800px;
    box-shadow: var(--shadow);
}
.form-title {
    font-size: 1.25rem;
    font-weight: 800;
    margin-bottom: 28px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 8px;
}
.form-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.form-group.full {
    grid-column: 1 / -1;
}
label {
    font-size: .85rem;
    font-weight: 700;
    color: var(--text);
    letter-spacing: 0.2px;
}
.required {
    color: var(--danger);
}
input[type="text"], input[type="password"], input[type="url"], input[type="number"], select, textarea {
    padding: 12px 16px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: .95rem;
    transition: var(--transition);
    width: 100%;
}
input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-glow);
}
.field-error {
    font-size: .8rem;
    color: var(--danger);
    font-weight: 600;
    margin-top: 2px;
}
.input-error {
    border-color: var(--danger) !important;
    box-shadow: 0 0 0 3px rgba(244, 63, 94, 0.15) !important;
}
textarea {
    resize: vertical;
    min-height: 120px;
}
.form-actions {
    display: flex;
    gap: 12px;
    margin-top: 12px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

/* Live Link Preview Panel in Admin Form */
#url-preview {
    margin: 20px 0;
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: var(--bg);
}

/* Premium Login Overlay */
.login-overlay {
    position: fixed;
    inset: 0;
    background: radial-gradient(circle at 30% 20%, #eff6ff 0%, #dbeafe 50%, #bfdbfe 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}
[data-theme="dark"] .login-overlay {
    background: radial-gradient(circle at 30% 20%, #090d16 0%, #0f172a 60%, #1e293b 100%);
}
.login-card {
    background: var(--surface-glass);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 46px 40px;
    width: 100%;
    max-width: 420px;
    box-shadow: var(--shadow-lg);
    animation: fadeInScale 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}
@keyframes fadeInScale {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}
.login-logo {
    text-align: center;
    margin-bottom: 32px;
}
.login-logo i {
    font-size: 3rem;
    color: var(--primary);
    filter: drop-shadow(0 4px 12px var(--primary-glow));
}
.login-logo h1 {
    font-size: 1.6rem;
    font-weight: 900;
    margin-top: 12px;
    letter-spacing: -0.5px;
}
.login-logo p {
    font-size: .9rem;
    color: var(--text-muted);
    margin-top: 4px;
}
.login-error {
    background: rgba(244, 63, 94, 0.12);
    color: var(--danger);
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: .88rem;
    font-weight: 600;
    margin-bottom: 20px;
    display: none;
    border: 1px solid rgba(244, 63, 94, 0.2);
}
.input-group {
    position: relative;
}
.input-group i.eye {
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
    cursor: pointer;
    color: var(--text-muted);
    transition: var(--transition);
}
.input-group i.eye:hover {
    color: var(--text);
}
@keyframes shake {
    0%, 100% { transform: none; }
    20%, 60% { transform: translateX(-8px); }
    40%, 80% { transform: translateX(8px); }
}
.shake {
    animation: shake .4s ease;
}

/* ==========================================================================
   RESPONSIVE & MOBILE POLISHING
   ========================================================================== */
@media (max-width: 992px) {
    .hero h1 {
        font-size: 2.8rem;
    }
}

@media (max-width: 768px) {
    /* Hide desktop admin sidebar, enable toggle */
    .sidebar {
        transform: translateX(-100%);
    }
    .sidebar.open {
        transform: translateX(0);
    }
    #sidebar-toggle {
        display: inline-flex !important;
    }
    .admin-main {
        margin-left: 0;
    }
    
    /* Responsive Hero Grid */
    .hero-inner {
        grid-template-columns: 1fr;
        gap: 36px;
        text-align: center;
    }
    .hero-badge {
        margin-left: auto;
        margin-right: auto;
    }
    .hero p {
        margin-left: auto;
        margin-right: auto;
    }
    .hero-actions {
        justify-content: center;
    }
    .hero-img {
        display: none;
    }
    .hero-stats {
        justify-content: center;
        gap: 24px;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .form-grid {
        grid-template-columns: 1fr;
    }
    .stats-grid {
        grid-template-columns: 1fr 1fr;
    }
    .nav-links {
        display: none;
    }
    .section-controls {
        flex-wrap: wrap;
        gap: 8px;
    }
    .books-grid {
        grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    }
}

/* ============================
   CARD IMAGE & THUMBNAIL
============================ */
.doc-card {
    padding: 0;
    display: flex;
    flex-direction: column;
}
.card-image {
    width: 100%;
    height: 160px;
    overflow: hidden;
    position: relative;
    border-radius: var(--radius) var(--radius) 0 0;
    background: var(--bg);
    flex-shrink: 0;
}
.card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s cubic-bezier(0.4,0,0.2,1);
    display: block;
}
.doc-card:hover .card-image img {
    transform: scale(1.07);
}
.card-image-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, transparent 50%, rgba(0,0,0,0.45) 100%);
    pointer-events: none;
}
.card-image-error {
    display: none !important;
}
/* Placeholder khi không có ảnh */
.card-image-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3.5rem;
    flex-shrink: 0;
}
.card-image-placeholder.icon-pdf { background: rgba(244,63,94,0.08); color: var(--danger); }
.card-image-placeholder.icon-docx { background: rgba(59,130,246,0.08); color: #2563eb; }
.card-image-placeholder.icon-pptx { background: rgba(245,158,11,0.08); color: var(--warning); }
.card-image-placeholder.icon-xlsx { background: rgba(16,185,129,0.08); color: var(--success); }
.card-image-placeholder.icon-default { background: rgba(100,116,139,0.08); color: var(--text-muted); }

/* Badge trên ảnh */
.card-ext-badge {
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: .7rem;
    z-index: 2;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.card-body {
    padding: 18px 20px 16px;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

/* Cập nhật card-top trong card-body */
.doc-card .card-top {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 0;
}
.doc-card .card-meta {
    flex: 1;
    min-width: 0;
}
.doc-card .card-subject {
    display: flex;
    align-items: center;
    gap: 5px;
}
.doc-card .card-desc {
    margin-bottom: 0;
    flex: 1;
}
.doc-card .card-footer {
    padding-top: 12px;
    align-items: center;
    gap: 8px;
}

/* Card date */
.card-date {
    font-size: .75rem;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 4px;
    white-space: nowrap;
}

/* Nút yêu thích trên card */
.card-fav-btn {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--border);
    font-size: 1.1rem;
    padding: 4px 6px;
    border-radius: 50%;
    transition: var(--transition);
    flex-shrink: 0;
    line-height: 1;
}
.card-fav-btn:hover {
    color: var(--danger);
    transform: scale(1.2);
}
.card-fav-btn.faved {
    color: var(--danger);
    animation: heartPop 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}
@keyframes heartPop {
    0% { transform: scale(1); }
    50% { transform: scale(1.4); }
    100% { transform: scale(1); }
}

/* ============================
   SECTION CONTROLS (Sort + View)
============================ */
.section-controls {
    display: flex;
    align-items: center;
    gap: 12px;
}
.sort-select {
    padding: 8px 14px;
    font-size: .85rem;
    min-width: 160px;
}
.view-toggle {
    display: flex;
    gap: 4px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 4px;
}
.view-btn {
    background: none;
    border: none;
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    transition: var(--transition);
    font-size: .9rem;
}
.view-btn:hover {
    color: var(--primary);
    background: var(--primary-light);
}
.view-btn.active {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 2px 8px var(--primary-glow);
}

/* ============================
   LIST VIEW MODE
============================ */
.docs-grid.list-view {
    grid-template-columns: 1fr;
    gap: 14px;
}
.docs-grid.list-view .doc-card {
    flex-direction: row;
    max-height: 130px;
}
.docs-grid.list-view .card-image,
.docs-grid.list-view .card-image-placeholder {
    width: 140px;
    min-width: 140px;
    height: 130px;
    border-radius: var(--radius) 0 0 var(--radius);
}
.docs-grid.list-view .card-body {
    padding: 14px 18px;
    gap: 6px;
}
.docs-grid.list-view .card-desc {
    -webkit-line-clamp: 1;
    min-height: unset;
}

/* ============================
   FAVORITES
============================ */
.fav-count-badge {
    position: absolute;
    top: -4px;
    right: -4px;
    background: var(--danger);
    color: #fff;
    border-radius: 99px;
    font-size: .65rem;
    font-weight: 800;
    min-width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 4px;
    border: 2px solid var(--surface);
}
#favorites-nav-btn {
    position: relative;
}
#favorites-nav-btn.has-fav {
    color: var(--danger);
    border-color: rgba(244,63,94,0.3);
}
.fav-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.fav-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--bg);
    transition: var(--transition);
}
.fav-item:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-sm);
}
.fav-thumb {
    width: 56px;
    height: 56px;
    object-fit: cover;
    border-radius: 8px;
    flex-shrink: 0;
}
.fav-thumb-placeholder {
    width: 56px;
    height: 56px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}
.fav-info {
    flex: 1;
    min-width: 0;
}
.fav-title {
    font-weight: 700;
    font-size: .95rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.fav-subject {
    font-size: .8rem;
    color: var(--primary);
    font-weight: 600;
    margin-top: 3px;
}
.fav-actions {
    display: flex;
    gap: 8px;
    flex-shrink: 0;
}
.fav-actions .btn {
    padding: 6px 12px;
    font-size: .8rem;
}

/* ============================
   MODAL THUMBNAIL
============================ */
.modal-thumb {
    width: 100%;
    height: 200px;
    overflow: hidden;
    border-radius: var(--radius-sm);
    margin-bottom: 20px;
}
.modal-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: var(--radius-sm);
}

/* ============================
   BOOKS SECTION
============================ */
.books-section {
    padding: 50px 0 80px;
    background: linear-gradient(180deg, var(--bg) 0%, rgba(99,102,241,0.03) 100%);
    border-top: 1px solid var(--border);
}
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 24px;
    margin-top: 8px;
}
.book-card {
    background: var(--surface-glass);
    backdrop-filter: blur(12px);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow: hidden;
    transition: var(--transition);
    box-shadow: var(--shadow);
    opacity: 0;
    transform: translateY(24px);
}
.book-card.visible {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.4s ease, transform 0.4s cubic-bezier(0.4,0,0.2,1), box-shadow 0.3s, border-color 0.3s;
}
.book-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--border-focus);
}
.book-cover {
    width: 100%;
    height: 200px;
    overflow: hidden;
    position: relative;
}
.book-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}
.book-card:hover .book-cover img {
    transform: scale(1.08);
}
.book-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, transparent 40%, rgba(0,0,0,0.6) 100%);
    display: flex;
    align-items: flex-end;
    padding: 14px;
}
.book-tag {
    background: var(--primary);
    color: #fff;
    font-size: .72rem;
    font-weight: 700;
    padding: 3px 10px;
    border-radius: 99px;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}
.book-info {
    padding: 18px 18px 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.book-cat {
    font-size: .73rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--primary);
}
.book-title {
    font-size: 1.05rem;
    font-weight: 800;
    line-height: 1.3;
    color: var(--text);
    letter-spacing: -0.2px;
}
.book-author {
    font-size: .82rem;
    color: var(--text-muted);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 5px;
}
.book-desc {
    font-size: .85rem;
    color: var(--text-muted);
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.book-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 6px;
    padding-top: 12px;
    border-top: 1px solid var(--border);
}
.book-search-btn {
    padding: 7px 14px;
    font-size: .8rem;
    border-radius: var(--radius-sm);
}

/* ============================
   BACK TO TOP
============================ */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary) 0%, #a855f7 100%);
    color: #fff;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 20px var(--primary-glow);
    z-index: 999;
    opacity: 0;
    transform: translateY(20px) scale(0.8);
    pointer-events: none;
    transition: opacity 0.3s ease, transform 0.3s cubic-bezier(0.34,1.56,0.64,1);
}
.back-to-top.visible {
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: all;
}
.back-to-top:hover {
    transform: translateY(-3px) scale(1.1);
    box-shadow: 0 8px 28px var(--primary-glow);
}

/* ============================
   STUDYNOTES UPGRADE PACK
============================ */
:root {
    --secondary: var(--text-muted);
}

.hero-upgraded {
    padding: 74px 0 58px;
}

.hero-upgraded .hero-inner {
    grid-template-columns: minmax(0, 1fr) 430px;
}

.hero-upgraded h1 {
    font-size: clamp(2.6rem, 6vw, 5.2rem);
    letter-spacing: 0;
}

.hero-panel {
    background: var(--surface-glass);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 24px;
    backdrop-filter: blur(16px);
}

.hero-panel-top,
.progress-label,
.bar-row-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.hero-panel-top {
    margin-bottom: 18px;
    font-weight: 800;
}

.hero-panel-top span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.hero-panel-top strong {
    color: var(--success);
    font-size: .85rem;
}

.hero-metric-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.hero-metric-grid > div {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 16px;
}

.hero-metric-grid span {
    display: block;
    color: var(--text-muted);
    font-size: .78rem;
    font-weight: 700;
    text-transform: uppercase;
}

.hero-metric-grid strong {
    display: block;
    color: var(--text);
    font-size: 1.35rem;
    margin-top: 4px;
}

.hero-progress {
    margin-top: 18px;
}

.progress-label {
    color: var(--text-muted);
    font-size: .86rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.progress-track,
.bar-track {
    height: 10px;
    background: var(--bg);
    border-radius: 999px;
    overflow: hidden;
    border: 1px solid var(--border);
}

.progress-track > div,
.bar-track > div {
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, var(--primary), var(--success));
    border-radius: inherit;
    transition: width .45s ease;
}

.upgraded-search {
    align-items: stretch;
}

.quick-filter-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 14px;
}

.quick-chip {
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-muted);
    border-radius: 999px;
    padding: 8px 14px;
    font-family: inherit;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.quick-chip:hover,
.quick-chip.active {
    color: #fff;
    border-color: var(--primary);
    background: var(--primary);
    box-shadow: 0 8px 18px var(--primary-glow);
}

.section-subtitle {
    color: var(--text-muted);
    font-size: .92rem;
    margin-top: 6px;
}

.insights-section {
    padding: 56px 0;
    background: var(--surface);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.insight-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 20px;
}

.insight-card {
    background: var(--surface-glass);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 22px;
}

.insight-card h3 {
    font-size: 1rem;
    margin-bottom: 18px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.bar-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.bar-row-top {
    color: var(--text);
    font-size: .9rem;
    font-weight: 700;
    margin-bottom: 7px;
}

.bar-row-top strong {
    color: var(--primary);
}

.mini-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.mini-item {
    width: 100%;
    display: grid;
    grid-template-columns: 36px 1fr;
    grid-template-areas: "icon title" "icon sub";
    gap: 2px 10px;
    text-align: left;
    border: 1px solid var(--border);
    background: var(--surface);
    border-radius: var(--radius-sm);
    padding: 10px;
    color: var(--text);
    cursor: pointer;
    transition: var(--transition);
}

.mini-item:hover {
    border-color: var(--primary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.mini-item span {
    grid-area: icon;
    width: 36px;
    height: 36px;
    border-radius: 10px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-light);
    color: var(--primary);
}

.mini-item strong {
    grid-area: title;
    font-size: .9rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.mini-item small {
    grid-area: sub;
    color: var(--text-muted);
}

.card-share-btn {
    width: 30px;
    height: 30px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-muted);
    border-radius: 999px;
    cursor: pointer;
    transition: var(--transition);
}

.card-share-btn:hover {
    color: var(--primary);
    border-color: var(--primary);
}

.empty-state.compact {
    padding: 18px;
}

#toast-wrap {
    position: fixed;
    right: 20px;
    bottom: 20px;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast-item {
    background: var(--surface);
    color: var(--text);
    border: 1px solid var(--border);
    border-left: 4px solid var(--primary);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
    padding: 12px 14px;
    min-width: 260px;
    font-weight: 700;
}

.toast-success { border-left-color: var(--success); }
.toast-error { border-left-color: var(--danger); }
.toast-warning { border-left-color: var(--warning); }

@media (max-width: 992px) {
    .hero-upgraded .hero-inner,
    .insight-grid {
        grid-template-columns: 1fr;
    }

    .hero-panel {
        max-width: 560px;
        margin: 0 auto;
    }
}

@media (max-width: 640px) {
    .hero-metric-grid,
    .stats-grid {
        grid-template-columns: 1fr;
    }

    .nav-actions {
        gap: 8px;
    }

    .nav-actions .btn {
        padding: 9px 12px;
    }

    .section-header {
        align-items: flex-start;
        flex-direction: column;
        gap: 14px;
    }

    .section-controls {
        width: 100%;
    }

    .sort-select {
        min-width: 0;
        flex: 1;
    }

    #toast-wrap {
        left: 14px;
        right: 14px;
    }

    .toast-item {
        min-width: 0;
    }
}

.admin-dashboard-grid {
    display: grid;
    grid-template-columns: 1.2fr .8fr;
    gap: 20px;
}

.admin-mini-doc {
    display: grid;
    grid-template-columns: 42px 1fr;
    gap: 12px;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.admin-mini-doc:last-child {
    border-bottom: 0;
}

.admin-mini-doc .file-icon {
    width: 42px;
    height: 42px;
    font-size: 1.05rem;
}

.admin-mini-doc strong,
.admin-mini-doc span {
    display: block;
}

.admin-mini-doc strong {
    font-size: .92rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.admin-mini-doc span {
    color: var(--text-muted);
    font-size: .8rem;
    margin-top: 2px;
}

.admin-filter-toolbar {
    justify-content: flex-start;
}

.admin-filter-toolbar .search-box {
    flex: 1 1 260px;
}

.admin-filter-toolbar .filter-select {
    flex: 0 1 190px;
}

.thumb-preview {
    margin-top: 10px;
    width: 100%;
    max-width: 360px;
    min-height: 120px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: var(--bg);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    font-weight: 700;
}

.thumb-preview img {
    width: 100%;
    height: 180px;
    object-fit: cover;
    display: block;
}

@media (max-width: 992px) {
    .admin-dashboard-grid {
        grid-template-columns: 1fr;
    }
}