/* ==========================================================================
   UNIVERSAL SLEEK CUSTOM SCROLLBARS
   ========================================================================== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: #f1f5f9;
    border-radius: 6px;
}
::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 6px;
    border: 2px solid #f1f5f9;
    transition: background 0.2s ease;
}
::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}
* {
    scrollbar-width: thin;
    scrollbar-color: #cbd5e1 #f1f5f9;
}

:root {
    --navy: #0f172a;
    --blue: #1d4ed8;
    --orange: #f97316;
    --orange-hover: #ea580c;
    --green: #10b981;
    --bg-light: #f8fafc;
    --text-main: #334155;
}

body {
    font-family: 'Poppins', sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--bg-light);
    /* Beautiful Dot-Matrix Graphic Background */
    background-image: radial-gradient(#cbd5e1 1.5px, transparent 1.5px);
    background-size: 30px 30px;
    color: var(--text-main);
}

/* --- NAVIGATION --- */
nav {
    background-color: var(--navy);
    padding: 15px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    position: relative;
    z-index: 100;
}

.logo-img {
    height: 52px;
    width: auto;
    max-width: 220px;
    object-fit: contain;
    display: block;
}

.nav-links a {
    color: white;
    text-decoration: none;
    margin-left: 25px;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--orange);
}

/* --- LAYOUT & CONTAINERS --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
    position: relative;
    z-index: 10;
}

.hero {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, var(--navy) 0%, #1e293b 100%);
    color: white;
    text-align: center;
    padding: 70px 20px;
    border-bottom: 4px solid var(--orange);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.2);
}

/* Floating Aesthetic Hero Graphics */
.hero::before {
    content: '';
    position: absolute;
    top: -50px; 
    left: -50px; 
    width: 250px; 
    height: 250px;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 50%;
}
.hero::after {
    content: '';
    position: absolute;
    bottom: -100px; 
    right: 5%; 
    width: 300px; 
    height: 300px;
    background: rgba(249, 115, 22, 0.1);
    border-radius: 50%;
    filter: blur(20px);
}

.form-card {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    max-width: 500px;
    margin: 0 auto;
}

/* --- FORMS & INPUTS --- */
input[type="text"], input[type="email"], input[type="password"], input[type="url"], select, textarea {
    width: 100%;
    padding: 12px;
    margin: 8px 0 20px 0;
    display: inline-block;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

button, .btn-submit {
    background-color: var(--orange);
    color: white;
    padding: 12px 20px;
    margin: 8px 0;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1em;
    transition: background 0.3s, transform 0.1s;
    font-family: 'Poppins', sans-serif;
}

button:hover {
    background-color: var(--orange-hover);
}

button:active {
    transform: scale(0.98);
}

/* --- BOOK CATALOG (GRID) --- */
.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 20px;
}

.book-card {
    background: white;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: transform 0.2s, box-shadow 0.2s;
    position: relative;
}

.book-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 20px rgba(0,0,0,0.1);
}

.search-bar {
    padding: 15px;
    width: 100%;
    max-width: 600px;
    border-radius: 30px;
    border: none;
    font-size: 1.1em;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    outline: none;
}

/* --- BADGES --- */
.badge {
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.8em;
    font-weight: 600;
}
.badge-catalog { background: #e0f2fe; color: #0284c7; }
.badge-pending { background: #fef3c7; color: #d97706; }
.badge-success { background: #dcfce3; color: #166534; }

/* --- GOOGLE BUTTON --- */
.btn-google {
    background-color: white;
    color: #334155;
    border: 1px solid #cbd5e1;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 500;
}
.btn-google:hover { background-color: #f8fafc; }
.social-logo { height: 20px; margin-right: 10px; }

/* --- AESTHETIC AUTHENTICATION UI (TABS) --- */
.nav-btn-highlight {
    background: var(--orange);
    color: white !important;
    padding: 8px 20px;
    border-radius: 25px;
    font-weight: 600 !important;
    transition: transform 0.2s, background 0.3s;
}
.nav-btn-highlight:hover {
    background: var(--orange-hover);
    transform: translateY(-2px);
}

.auth-container {
    max-width: 550px;
    margin: 40px auto;
    background: white;
    border-radius: 16px;
    box-shadow: 0 20px 40px rgba(11, 28, 58, 0.08);
    overflow: hidden;
    border-top: 5px solid var(--orange);
}

.auth-tabs {
    display: flex;
    background: #f8fafc;
    border-bottom: 1px solid #e2e8f0;
}

.auth-tab {
    flex: 1;
    padding: 18px 10px;
    text-align: center;
    border: none;
    background: transparent;
    font-size: 0.95em;
    font-weight: 600;
    color: #64748b;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'Poppins', sans-serif;
}

.auth-tab:hover {
    color: var(--navy);
    background: #f1f5f9;
}

.auth-tab.active {
    background: white;
    color: var(--orange);
    border-bottom: 3px solid var(--orange);
}

.auth-content {
    display: none;
    padding: 40px;
    animation: fadeIn 0.4s ease-in-out;
}

.auth-content.active {
    display: block;
}

.auth-icon {
    font-size: 2.5em;
    margin-bottom: 15px;
    display: inline-block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- UTILITIES & DASHBOARD --- */
.scroll-progress-container {
    width: 100%;
    height: 4px;
    background: #e2e8f0;
    position: fixed;
    top: 0;
    z-index: 1000;
}
.scroll-progress-bar {
    height: 4px;
    background: var(--orange);
    width: 0%;
}
.admin-panel {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    margin-bottom: 30px;
}
.admin-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.admin-list li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    border-bottom: 1px solid #e2e8f0;
}
.admin-list li:last-child {
    border-bottom: none;
}
/* --- SIDEBAR MENU (HAMBURGER) --- */
.hamburger-btn {
    font-size: 28px;
    cursor: pointer;
    color: white;
    background: none;
    border: none;
    padding: 0 15px 0 0;
    transition: color 0.3s;
}
.hamburger-btn:hover { color: var(--orange); }

.sidebar {
    height: 100%;
    width: 0;
    position: fixed;
    z-index: 3000;
    top: 0;
    left: 0;
    background-color: var(--navy);
    overflow-x: hidden;
    transition: 0.3s;
    padding-top: 60px;
    box-shadow: 5px 0 15px rgba(0,0,0,0.5);
}
.sidebar a {
    padding: 15px 30px;
    text-decoration: none;
    font-size: 1.1em;
    color: white;
    display: block;
    transition: 0.2s;
    border-bottom: 1px solid rgba(255,255,255,0.05);
}
.sidebar a:hover {
    color: var(--orange);
    background: rgba(255,255,255,0.05);
    padding-left: 40px; /* Slight slide effect on hover */
}
.sidebar .close-btn {
    position: absolute;
    top: 15px;
    right: 25px;
    font-size: 36px;
    margin-left: 50px;
    border: none;
    border-bottom: none;
}
.sidebar .close-btn:hover {
    background: transparent;
    padding-left: 30px;
}
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 23, 42, 0.6);
    z-index: 2500;
    backdrop-filter: blur(3px);
}
/* PustakVerse visual refresh */
:root { --surface: #ffffff; --muted: #64748b; }
body { font-family: 'DM Sans', sans-serif; background-color: #f7f5f0; background-image: radial-gradient(rgba(194,183,160,.28) 1px, transparent 1px); background-size: 26px 26px; }
nav { background: rgba(15,23,42,.94); position: sticky; top: 0; backdrop-filter: blur(14px); }
.nav-brand { display: flex; align-items: center; }
.theme-toggle { margin: 0 0 0 18px; padding: 7px 10px; background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.18); border-radius: 50%; line-height: 1; }
.theme-toggle:hover { background: rgba(255,255,255,.2); }
.sidebar h3 { color: #94a3b8; padding-left: 30px; font-size: .75rem; text-transform: uppercase; letter-spacing: .14em; margin-top: 22px; }
.sidebar .close-btn { position: absolute; top: 12px; right: 17px; width: 38px; height: 38px; padding: 0; font-size: 2rem; line-height: 1; background: transparent; }
.flash-container { padding-bottom: 0; }.flash-message { padding: 14px 16px; margin-bottom: 14px; border-radius: 10px; text-align: center; font-weight: 600; background: #dcfce7; color: #166534; }.flash-message.error { background: #fee2e2; color: #991b1b; }
.hero { padding: 92px 20px 72px; }.hero-content { position: relative; z-index: 1; max-width: 840px; margin: 0 auto; }.hero h1 { font-family: 'Playfair Display', serif; font-size: clamp(2.7rem, 6vw, 4.9rem) !important; letter-spacing: -2px !important; line-height: 1.08; margin: 14px 0; }.hero-subtitle { max-width: 650px; margin: 0 auto; font-size: 1.15rem !important; line-height: 1.75; opacity: .88; }.eyebrow { color: var(--orange); font-size: .72rem; font-weight: 700; letter-spacing: .16em; }.hero .eyebrow { color: #fdba74; }.hero-stats { position: relative; z-index: 1; display: flex; justify-content: center; flex-wrap: wrap; gap: 12px 28px; margin-top: 32px; color: #dbeafe; font-size: .9rem; }.hero-stats strong { color: #fff; }
.search-wrap { position: relative; max-width: 560px; margin: 25px auto 0; }.search-bar { width: 100%; box-sizing: border-box; padding: 16px 54px 16px 20px; border-radius: 14px; box-shadow: 0 12px 28px rgba(0,0,0,.16); }.voice-search { position: absolute; right: 9px; top: 9px; margin: 0; padding: 6px 11px; background: transparent; color: var(--navy); font-size: 1.6rem; }.voice-search:hover { background: #f1f5f9; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 8px; }.section-heading h2 { font-family: 'Playfair Display', serif; font-size: 2rem; margin: 5px 0; color: var(--navy); }.search-status { color: var(--muted); font-size: .9rem; }
.book-card { background: var(--surface); border-radius: 18px; box-shadow: 0 8px 24px rgba(15,23,42,.07); border: 1px solid rgba(15,23,42,.06); overflow: hidden; }.book-card > img { width: 100%; height: 250px; object-fit: cover; border-radius: 10px; margin-bottom: 15px; transition: transform .4s ease; }.book-card:hover > img { transform: scale(1.025); }.book-card h3 { margin: 14px 0 6px; font-family: 'Playfair Display', serif; font-size: 1.35rem; }.book-author { color: var(--muted); font-size: .95rem; }.read-book { display: flex; justify-content: space-between; align-items: center; margin-top: 15px; padding: 10px 13px; border-radius: 9px; text-decoration: none; font-weight: 700; color: white; background: var(--orange); }.read-book:hover { background: var(--orange-hover); }.save-book { width: 100%; background: transparent; color: var(--navy); border: 2px solid var(--navy); padding: 8px; margin-top: 7px; }.save-book:hover { color: #fff; background: var(--navy); }.btn-share { width: 100%; background: transparent; color: var(--muted); padding: 8px; margin: 8px 0 0; font-size: .85rem; }.btn-share:hover { color: var(--navy); background: #f1f5f9; }.empty-state { background: var(--surface); padding: 30px; border-radius: 14px; grid-column: 1 / -1; text-align: center; }
.popup-overlay { opacity: 0; visibility: hidden; position: fixed; inset: 0; z-index: 4000; display: grid; place-items: center; padding: 20px; background: rgba(15,23,42,.68); backdrop-filter: blur(8px); transition: opacity .25s ease, visibility .25s ease; }.popup-overlay.is-visible { opacity: 1; visibility: visible; }.popup-content { width: min(100%, 500px); position: relative; overflow: hidden; border: 1px solid rgba(255,255,255,.6); border-radius: 24px; padding: 42px 38px 30px; text-align: center; background: linear-gradient(145deg,#fffdf8,#f8f1e6); box-shadow: 0 30px 70px rgba(0,0,0,.28); }.popup-content::before { content: ''; position: absolute; width: 260px; height: 260px; top: -160px; right: -120px; border-radius: 50%; background: rgba(249,115,22,.16); }.popup-close { position: absolute; top: 13px; right: 16px; padding: 0; width: 34px; height: 34px; border-radius: 50%; background: #fff; color: var(--navy); font-size: 1.65rem; line-height: 1; }.popup-kicker { position: relative; color: var(--orange); font-size: .66rem; letter-spacing: .16em; font-weight: 700; }.popup-orbit { position: relative; width: 92px; height: 92px; margin: 17px auto; border: 1px solid rgba(249,115,22,.25); border-radius: 50%; animation: float 4s ease-in-out infinite; }.popup-orbit span { position: absolute; color: var(--orange); font-size: .7rem; }.popup-orbit span:nth-child(1) { left: 8px; top: 17px; }.popup-orbit span:nth-child(2) { right: 8px; top: 40px; }.popup-orbit span:nth-child(3) { left: 28px; bottom: 5px; }.popup-book { position: absolute; inset: 19px; display: grid; place-items: center; border-radius: 14px 5px 5px 14px; background: var(--navy); color: #fff; font-family: 'Playfair Display', serif; font-size: 1.15rem; box-shadow: 6px 6px 0 #f97316; }.popup-content h2 { position: relative; font-family: 'Playfair Display', serif; color: var(--navy); font-size: 2rem; margin: 0 0 10px; }.popup-content p { position: relative; margin: 0 auto; max-width: 390px; color: var(--muted); line-height: 1.65; }.popup-perks { position: relative; display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; margin: 19px 0; }.popup-perks span { padding: 6px 9px; border-radius: 99px; background: rgba(255,255,255,.75); color: #475569; font-size: .75rem; }.popup-btn { position: relative; display: flex; justify-content: center; gap: 28px; align-items: center; background: var(--navy); color: #fff; border-radius: 12px; padding: 14px 18px; text-decoration: none; font-weight: 700; transition: transform .2s, background .2s; }.popup-btn:hover { background: #1e293b; transform: translateY(-2px); }.popup-btn span { font-size: 1.2rem; }.close-popup { background: transparent; color: var(--muted); margin-top: 7px; font-size: .82rem; }.close-popup:hover { background: transparent; color: var(--navy); }.back-to-top { position: fixed; right: 20px; bottom: 20px; z-index: 2000; width: 44px; height: 44px; padding: 0; border-radius: 50%; opacity: 0; pointer-events: none; transform: translateY(10px); box-shadow: 0 8px 20px rgba(15,23,42,.25); transition: .2s; }.back-to-top.is-visible { opacity: 1; pointer-events: auto; transform: translateY(0); } @keyframes float { 50% { transform: translateY(-7px) rotate(4deg); } }
.dark-theme { --surface: #1e293b; --text-main: #dbeafe; --muted: #aab7c9; background-color: #111827; background-image: radial-gradient(rgba(148,163,184,.18) 1px,transparent 1px); }.dark-theme .book-card, .dark-theme .form-card, .dark-theme .auth-container, .dark-theme .admin-panel { border-color: rgba(255,255,255,.09); }.dark-theme .section-heading h2, .dark-theme .book-card h3 { color: #f8fafc; }.dark-theme .btn-share:hover { background: #334155; color: #fff; }

/* Warm Sepia Eye-Care Theme */
.sepia-theme { --surface: #fdf6e2; --text-main: #382c1e; --muted: #796855; background-color: #f4ecd8; background-image: radial-gradient(rgba(138,109,59,.18) 1px, transparent 1px); }
.sepia-theme .book-card, .sepia-theme .form-card, .sepia-theme .auth-container, .sepia-theme .admin-panel, .sepia-theme .checkout-card { background: #fdf6e2; border-color: #e5d8b8; color: #382c1e; }
.sepia-theme .section-heading h2, .sepia-theme .book-card h3, .sepia-theme h1, .sepia-theme h2 { color: #2b1f11; }
.sepia-theme nav { background: rgba(43,33,24,.95); }
.sepia-theme .read-book { background: #b45309; }
.sepia-theme .read-book:hover { background: #92400e; }

/* Global Search Autocomplete Dropdown */
.nav-search { position: relative; }
.search-autocomplete-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    left: 0;
    right: 0;
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    box-shadow: 0 12px 30px rgba(0,0,0,0.15);
    z-index: 2000;
    max-height: 380px;
    overflow-y: auto;
    display: none;
}
.dark-theme .search-autocomplete-dropdown { background: #1e293b; border-color: #334155; }
.sepia-theme .search-autocomplete-dropdown { background: #fdf6e2; border-color: #e5d8b8; }
.autocomplete-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 14px;
    text-decoration: none;
    color: inherit;
    border-bottom: 1px solid rgba(0,0,0,0.05);
    transition: background 0.15s;
}
.autocomplete-item:last-child { border-bottom: none; }
.autocomplete-item:hover { background: rgba(249,115,22,0.08); }
.autocomplete-thumb {
    width: 36px;
    height: 48px;
    object-fit: cover;
    border-radius: 4px;
    background: #e2e8f0;
}
.autocomplete-info { flex: 1; min-width: 0; }
.autocomplete-title { font-weight: 700; font-size: 0.9rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: #0f172a; }
.dark-theme .autocomplete-title { color: #f8fafc; }
.sepia-theme .autocomplete-title { color: #2b1f11; }
.autocomplete-meta { font-size: 0.78rem; color: #64748b; }
.autocomplete-price { font-weight: 700; font-size: 0.85rem; color: #16a34a; }

@media (max-width: 720px) { nav { padding: 12px 18px; }.nav-links a:not(.nav-btn-highlight) { display: none; }.logo-img { height: 42px; }.theme-toggle { margin-left: 8px; }.hero { padding: 68px 18px 54px; }.container { padding: 30px 16px; }.section-heading { align-items: flex-start; flex-direction: column; gap: 4px; }.popup-content { padding: 38px 23px 25px; }.popup-content h2 { font-size: 1.65rem; } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; transition-duration: .01ms !important; } }
.pricing-box { margin-top: 18px; padding: 15px; border: 1px solid #fed7aa; border-radius: 10px; background: #fff7ed; }.paid-toggle { display: flex; align-items: center; gap: 9px; color: var(--navy); font-weight: 700; cursor: pointer; }.paid-toggle input { width: auto; margin: 0; accent-color: var(--orange); }.pricing-box small { display: block; margin-top: 6px; color: #64748b; line-height: 1.45; }.price-tag { display: inline-block; margin: 10px 0 0; padding: 5px 10px; border-radius: 99px; background: #fff7ed; color: #c2410c; font-weight: 700; font-size: .9rem; }.checkout-card { width: min(100%, 520px); margin: 30px auto; padding: 34px; background: var(--surface); border: 1px solid rgba(15,23,42,.08); border-radius: 18px; box-shadow: 0 16px 38px rgba(15,23,42,.1); }.checkout-card h1 { margin: 8px 0 28px; color: var(--navy); font-family: 'Playfair Display', serif; }.checkout-line, .checkout-total { display: flex; justify-content: space-between; gap: 20px; padding: 12px 0; color: var(--muted); }.checkout-total { border-top: 1px solid #e2e8f0; margin-top: 8px; color: var(--navy); font-size: 1.2rem; }.checkout-note { margin: 20px 0; color: var(--muted); line-height: 1.55; }.checkout-card button { width: 100%; }.checkout-cancel { display: block; margin-top: 12px; text-align: center; color: var(--muted); text-decoration: none; font-size: .9rem; }




/* ==========================================================================
   PUSTAKVERSE UNIVERSAL MOBILE APP-GRADE RESPONSIVENESS (< 768px & < 480px)
   ========================================================================== */

/* Universal Touch & Smoothness */
* {
    -webkit-tap-highlight-color: transparent;
    box-sizing: border-box;
}

/* Prevent auto-zooming on input focus on iOS Safari */
input, textarea, select {
    font-size: 16px !important;
}

@media (max-width: 768px) {
    /* Base Body padding for bottom bar */
    

    /* Modern Mobile Header Navbar */
    nav, .navbar {
        padding: 10px 14px !important;
        height: 60px !important;
        display: flex !important;
        flex-direction: row !important;
        align-items: center !important;
        justify-content: space-between !important;
        gap: 8px !important;
        position: sticky !important;
        top: 0 !important;
        z-index: 1000 !important;
        background: #1e293b !important;
        box-shadow: 0 4px 15px rgba(0,0,0,0.15) !important;
    }

    .nav-brand, .navbar-brand {
        display: flex !important;
        align-items: center !important;
        gap: 10px !important;
    }

    .logo-img, .navbar-brand img {
        height: 38px !important;
        max-width: 140px !important;
    }

    /* Hide desktop nav links on mobile (accessible via bottom dock & drawer) */
    .nav-links, .navbar-links {
        display: none !important;
    }

    .nav-search {
        display: none !important; /* Replaced by hero search & bottom search */
    }

    /* Hero Section Responsive */
    .hero, .hero-section {
        padding: 34px 16px 26px !important;
        text-align: center !important;
    }

    .hero h1, .hero-section h1 {
        font-size: 1.95rem !important;
        line-height: 1.18 !important;
        letter-spacing: -0.5px !important;
        margin-bottom: 6px !important;
    }

    .hero-subtitle, .hero-section p {
        font-size: 0.9rem !important;
        line-height: 1.45 !important;
        color: #94a3b8 !important;
        margin-bottom: 18px !important;
    }

    .search-container, .search-wrap {
        width: 100% !important;
        max-width: 100% !important;
        margin: 12px 0 0 !important;
        padding: 4px 12px !important;
        border-radius: 28px !important;
        box-shadow: 0 4px 15px rgba(0,0,0,0.12) !important;
    }

    .search-container input, .search-bar {
        font-size: 0.95rem !important;
        padding: 10px 6px !important;
    }

    /* Filter & Category Carousel */
    .filter-nav, .filter-nav-scroll {
        display: flex !important;
        gap: 8px !important;
        overflow-x: auto !important;
        white-space: nowrap !important;
        padding: 10px 14px !important;
        scrollbar-width: none !important;
        -webkit-overflow-scrolling: touch !important;
        justify-content: flex-start !important;
    }
    .filter-nav::-webkit-scrollbar, .filter-nav-scroll::-webkit-scrollbar { display: none !important; }

    .filter-nav a, .filter-nav-scroll a {
        padding: 6px 14px !important;
        border-radius: 20px !important;
        font-size: 0.8rem !important;
        min-height: 36px !important;
        flex-shrink: 0 !important;
    }

    /* Container & Layout */
    .container {
        padding: 16px 12px !important;
        max-width: 100% !important;
    }

    /* Sleek 2-Column Mobile Book Catalog Grid */
    .book-grid {
        display: grid !important;
        grid-template-columns: repeat(2, 1fr) !important;
        gap: 12px !important;
        margin-top: 10px !important;
    }

    .book-card {
        padding: 8px !important;
        border-radius: 14px !important;
        box-shadow: 0 4px 12px rgba(0,0,0,0.06) !important;
    }

    .book-cover, .book-card > img {
        width: 100% !important;
        height: auto !important;
        aspect-ratio: 2 / 3 !important;
        border-radius: 10px !important;
        object-fit: cover !important;
    }

    .book-info {
        padding: 8px 4px 4px !important;
    }

    .book-tag {
        font-size: 0.68rem !important;
        margin-bottom: 3px !important;
    }

    .book-title, .book-card h3 {
        font-size: 0.88rem !important;
        line-height: 1.25 !important;
        margin: 0 0 3px 0 !important;
        display: -webkit-box !important;
        -webkit-line-clamp: 2 !important;
        -webkit-box-orient: vertical !important;
        overflow: hidden !important;
    }

    .book-author {
        font-size: 0.76rem !important;
        margin-bottom: 8px !important;
        white-space: nowrap !important;
        overflow: hidden !important;
        text-overflow: ellipsis !important;
    }

    .book-actions {
        flex-direction: column !important;
        gap: 5px !important;
        margin-top: auto !important;
    }

    .btn, .btn-read, .btn-save, .btn-premium {
        padding: 8px 0 !important;
        font-size: 0.82rem !important;
        min-height: 38px !important;
        border-radius: 8px !important;
    }

    /* GranthMind AI Floating Badge adjustment on mobile */
    .floating-granthmind-btn {
        display: none !important; /* Replaced by bottom navigation center AI tab */
    }

    /* Modals & Popups on Mobile */
    .popup-box, .auth-modal-box {
        width: 92% !important;
        max-width: 92% !important;
        padding: 24px 18px !important;
        border-radius: 18px !important;
    }

    .popup-box h2 {
        font-size: 1.4rem !important;
    }

    /* Forms, Login & Register on Mobile */
    .auth-card, .login-box, .register-box, .checkout-card {
        width: 100% !important;
        padding: 22px 16px !important;
        margin: 16px auto !important;
        border-radius: 16px !important;
    }