/* reading.css (Жаңартылған нұсқа) */

/* Негізгі контейнер */
.reading-container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 20px;
    padding-bottom: 40px;
}

.reading-header {
    text-align: center;
    margin-bottom: 40px;
}

/* Footer - кітаптар көзі туралы ақпарат */
.reading-footer {
    margin-top: 60px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color, #e2e8f0);
    text-align: center;
}

.reading-footer-text {
    font-size: 14px;
    color: var(--primary-color, #64748b);
    line-height: 1.6;
    margin: 0;
}

.reading-footer-link {
    color: var(--primary-color, #3b82f6);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.reading-footer-link:hover {
    color: var(--primary-color, #2563eb);
    text-decoration: underline;
}

.reading-title {
    font-size: 2.5rem;
    font-weight: 800;
}

.reading-subtitle {
    font-size: 1.1rem;
    color: #666;
}

/* Пән сүзгілері (Фильтр) */
.subject-filters {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    margin-bottom: 50px;
}

.filter-btn {
    padding: 9px 18px;
    font-size: 0.95rem;
    font-weight: 600;
    border: 1px solid var(--border-color);
    background: transparent;
    color: var(--primary-color);
    border-radius: 100px;
    cursor: pointer;
    transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.filter-btn:hover {
    background: var(--hover-color);
}

.filter-btn.active {
    background: var(--primary-color);
    color: var(--secondary-color);
    border-color: var(--primary-color);
}

/* Пән түстері арқылы активті filter батырмалары */
.filter-btn.active[data-subject="history"] {
    background-color: var(--color-history);
    color: white;
}

.filter-btn.active[data-subject="world_history"] {
    background-color: var(--color-world_history);
    color: white;
}

.filter-btn.active[data-subject="informatics"] {
    background-color: var(--color-informatics);
    color: white;
}

.filter-btn.active[data-subject="physics"] {
    background-color: var(--color-physics);
    color: white;
}

.filter-btn.active[data-subject="chemistry"] {
    background-color: var(--color-chemistry);
    color: white;
}

.filter-btn.active[data-subject="law_basics"] {
    background-color: var(--color-law_basics);
    color: white;
}

.filter-btn.active[data-subject="biology"] {
    background-color: var(--color-biology);
    color: white;
}

.filter-btn.active[data-subject="geography"] {
    background-color: var(--color-geography);
    color: white;
}

.filter-btn.active[data-subject="english"] {
    background-color: var(--color-english);
    color: white;
}

.filter-btn.active[data-subject="kazakh_language"] {
    background-color: var(--color-kazakh_language);
    color: white;
}

.filter-btn.active[data-subject="kazakh_literature"] {
    background-color: var(--color-kazakh_literature);
    color: white;
}

.filter-btn.active[data-subject="russian_language_and_literature"] {
    background-color: var(--color-russian_language_and_literature);
    color: white;
}

.filter-btn.active[data-subject="Барлығы"] {
    background-color: #333;
    color: white;
}

/* Кітаптар тобы */
.book-group {
    margin-bottom: 56px;
}

.subject-title {
    font-size: 1.45rem;
    font-weight: 700;
    margin-bottom: 22px;
    color: var(--primary-color);
    letter-spacing: -0.02em;
}

.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 22px;
}

/* Кітап карточкасы — flat, заманауи */
.book-card {
    border-radius: 20px;
    cursor: pointer;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    background: var(--ekinshi-color);
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.book-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 14px 30px rgba(0, 0, 0, 0.13);
    border-color: transparent;
}

/* Мұқаба — біртұтас жалпақ түс */
.book-cover {
    height: 300px;
    color: #fff;
    padding: 22px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: relative;
    font-family: 'Outfit', sans-serif;
    overflow: hidden;
}

/* Мәтін оқылуы үшін жұқа scrim (flat, бірақ контрастты) */
.book-cover::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.10) 0%, transparent 28%, transparent 62%, rgba(0, 0, 0, 0.20) 100%);
    pointer-events: none;
}

/* Пән түстері үшін CSS Variables */
:root {
    --color-biology: #34C759;
    --color-physics: #8A2BE2;
    --color-history: #A52A2A;
    --color-informatics: #4682B4;
    --color-chemistry: #00B7EB;
    --color-world_history: #FF4500;
    --color-geography: #2E8B57;
    --color-english: #FF69B4;
    --color-kazakh_language: #b64861;
    --color-kazakh_literature: #bb8f53;
    --color-law_basics: #1fcbcb;
    --color-russian_language_and_literature: #5164ae;
    --color-default: #777;
    
    /* Жаңа түстер PDF оқу интерфейсі үшін */
    --pdf-header-bg: #ffffff;
    --pdf-body-bg: #f0f2f5;
    --pdf-footer-bg: #ffffff;
    --pdf-controls-bg: #e9ecef;
    --pdf-controls-hover: #dbe0e4;
    --pdf-controls-active: #c6cfd8;
    --pdf-text: #333333;
    --pdf-border: #e5e5e5;
    --pdf-shadow: rgba(0, 0, 0, 0.15);
    --pdf-button-primary: #3498db;
    --pdf-button-primary-hover: #2980b9;
}

    /* Түсін пәнге сәйкестендіру (PDF modal үшін) */
    .pdf-modal[data-subject-key="history"] { --pdf-button-primary: var(--color-history); }
    .pdf-modal[data-subject-key="world_history"] { --pdf-button-primary: var(--color-world_history); }
    .pdf-modal[data-subject-key="informatics"] { --pdf-button-primary: var(--color-informatics); }
    .pdf-modal[data-subject-key="physics"] { --pdf-button-primary: var(--color-physics); }
    .pdf-modal[data-subject-key="chemistry"] { --pdf-button-primary: var(--color-chemistry); }
    .pdf-modal[data-subject-key="law_basics"] { --pdf-button-primary: var(--color-law_basics); }
    .pdf-modal[data-subject-key="biology"] { --pdf-button-primary: var(--color-biology); }
    .pdf-modal[data-subject-key="geography"] { --pdf-button-primary: var(--color-geography); }
    .pdf-modal[data-subject-key="english"] { --pdf-button-primary: var(--color-english); }
    .pdf-modal[data-subject-key="kazakh_language"] { --pdf-button-primary: var(--color-kazakh_language); }
    .pdf-modal[data-subject-key="kazakh_literature"] { --pdf-button-primary: var(--color-kazakh_literature); }
    .pdf-modal[data-subject-key="russian_language_and_literature"] { --pdf-button-primary: var(--color-russian_language_and_literature); }
    .pdf-modal[data-subject-key="default"] { --pdf-button-primary: var(--color-default); }

/* Түстерді фонға қолдану */
.cover-history { background-color: var(--color-history); }
.cover-world_history { background-color: var(--color-world_history); }
.cover-informatics { background-color: var(--color-informatics); }
.cover-physics { background-color: var(--color-physics); }
.cover-chemistry { background-color: var(--color-chemistry); }
.cover-law_basics { background-color: var(--color-law_basics); }
.cover-biology { background-color: var(--color-biology); }
.cover-geography { background-color: var(--color-geography); }
.cover-english { background-color: var(--color-english); }
.cover-kazakh_language { background-color: var(--color-kazakh_language); }
.cover-kazakh_literature { background-color: var(--color-kazakh_literature); }
.cover-russian_language_and_literature { background-color: var(--color-russian_language_and_literature); }
.cover-default { background-color: var(--color-default); }


.cover-grade {
    font-size: 0.8rem;
    font-weight: 700;
    background: rgba(255, 255, 255, 0.22);
    padding: 6px 14px;
    border-radius: 100px;
    align-self: flex-start;
    position: relative;
    z-index: 2;
}

.cover-title {
    font-size: 1.95rem;
    font-weight: 800;
    line-height: 1.12;
    margin: 0;
    position: relative;
    z-index: 2;
    letter-spacing: -0.02em;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.18);
}

/* Ұзын атаулар үшін кіші өлшем */
.cover-title.long-title {
    font-size: 1.4rem;
}

.cover-title.very-long-title {
    font-size: 1.2rem;
}

.cover-publisher {
    font-size: 0.9rem;
    font-weight: 600;
    opacity: 0.95;
    position: relative;
    z-index: 2;
    align-self: flex-start;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.18);
}

.book-details {
    padding: 15px 18px;
    background: var(--ekinshi-color);
    flex-grow: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border-top: 1px solid var(--border-color);
}

.book-details .authors {
    font-size: 0.88rem;
    color: var(--primary-color);
    opacity: 0.6;
    margin: 0;
    font-weight: 500;
    line-height: 1.4;
    text-align: center;
}

/* PDF Viewer стильдері - Жаңартылған */
.pdf-modal {
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
    display: none;
    justify-content: center;
    align-items: center;
    overscroll-behavior: contain;
}

.pdf-modal-content {
    /* Fullscreen transparent container over dark overlay */
    position: relative;
    background-color: transparent;
    width: 100%;
    max-width: none;
    height: 100vh;
    border-radius: 0;
    display: flex;
    flex-direction: column;
    box-shadow: none;
    overflow: hidden;
}

.pdf-header { display: none; }

#pdf-title { display: none; }

.close-btn {
    position: fixed;
    top: 16px;
    right: 16px;
    width: 44px;
    height: 44px;
    border: 1.5px solid rgba(255, 255, 255, 0.65); /* circular line */
    background: rgba(0, 0, 0, 0.55);
    color: #fff;
    border-radius: 50%;
    cursor: pointer;
    display: inline-flex; /* allow perfect centering */
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s ease, transform 0.1s ease, border-color 0.2s ease;
    z-index: 1002;
    box-shadow: 0 2px 8px rgba(0,0,0,0.35);
}

.close-btn svg {
    width: 22px;
    height: 22px;
    display: block;
}

.close-btn:hover { background: rgba(0, 0, 0, 0.7); border-color: rgba(255,255,255,0.8); }
.close-btn:active { transform: scale(0.95); }

/* Zoom toggle button */
.zoom-toggle-btn {
    position: fixed;
    top: 16px;
    right: 76px;
    width: 44px;
    height: 44px;
    border: 1.5px solid rgba(255, 255, 255, 0.65);
    background: rgba(0, 0, 0, 0.55);
    color: #fff;
    border-radius: 50%;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s ease, transform 0.1s ease, border-color 0.2s ease;
    z-index: 1002;
}

.zoom-toggle-btn svg {
    width: 20px;
    height: 20px;
    display: block;
}

.zoom-toggle-btn:hover { background: rgba(0, 0, 0, 0.7); border-color: rgba(255,255,255,0.8); }
.zoom-toggle-btn:active { transform: scale(0.95); }

/* Толық экран батырмасы — zoom-нан сол жақта (батырмалар арасы кеңейтілді) */
#fullscreen-btn { right: 136px; }

/* "1/2 бет" ауыстырғышы — тек кең экранда (десктоп/ноут) */
#twopage-btn { right: 196px; }
@media (max-width: 1023px) {
    #twopage-btn { display: none; }
}

/* Белсенді ауыстырғыш күйі (екі бет қосулы) */
.zoom-toggle-btn.active {
    background: rgba(102, 126, 234, 0.85);
    border-color: rgba(255, 255, 255, 0.9);
}

/* ===== Кітап жүктелу кезінде артық элементтерді жасыру (тек ✕ қалады) ===== */
#zoom-toggle-btn, #fullscreen-btn, #twopage-btn { transition: opacity 0.35s ease, transform 0.35s ease; }
.pdf-footer { transition: opacity 0.35s ease, transform 0.35s ease; }
.pdf-modal.pdf-loading #zoom-toggle-btn,
.pdf-modal.pdf-loading #fullscreen-btn,
.pdf-modal.pdf-loading #twopage-btn {
    opacity: 0;
    transform: translateY(-8px);
    pointer-events: none;
}
.pdf-modal.pdf-loading .pdf-footer {
    opacity: 0;
    transform: translateX(-50%) translateY(12px);
    pointer-events: none;
}

/* ===== Shimmer skeleton (кітап оқу / үйрену беттері) ===== */
@keyframes skel-shimmer {
    0%   { background-position: 100% 0; }
    100% { background-position: -100% 0; }
}
.skeleton {
    background: linear-gradient(90deg,
        var(--hover-color, #eee) 25%,
        rgba(var(--primary-color-rgb, 0, 0, 0), 0.06) 37%,
        var(--hover-color, #eee) 63%);
    background-size: 400% 100%;
    animation: skel-shimmer 1.4s ease-in-out infinite;
    border-radius: 10px;
}
.skeleton-grid {
    display: grid;
    gap: 22px;
    padding: 8px 0 20px;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
}
.skeleton-card { display: flex; flex-direction: column; gap: 12px; }
.skel-cover-34 { width: 100%; aspect-ratio: 3 / 4; border-radius: 16px; }
.skel-cover-11 { width: 100%; aspect-ratio: 1 / 1; border-radius: 12px; }
.skel-line { height: 14px; width: 75%; }
.skel-line.short { height: 12px; width: 45%; }
@media (prefers-reduced-motion: reduce) {
    .skeleton { animation: none; }
}

.zoom-toggle-btn.zoomed-in {
    background: rgba(102, 126, 234, 0.8);
    border-color: rgba(255, 255, 255, 0.9);
}

.zoom-toggle-btn.zoomed-in svg path:nth-child(3) {
    display: none; /* Жақындатылған кезде + белгісіндегі вертикаль сызықты жасыру */
}

.pdf-body {
    flex-grow: 1;
    overflow: auto;
    background-color: transparent; /* Only canvas is visible over dark overlay */
    padding: 0;
    position: relative;
    scrollbar-width: thin;
    scrollbar-color: #555 transparent;
}

.pdf-body::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

.pdf-body::-webkit-scrollbar-track {
    background: #f1f1f1;
}

.pdf-body::-webkit-scrollbar-thumb {
    background: #bbb;
    border-radius: 4px;
}

.pdf-body::-webkit-scrollbar-thumb:hover {
    background: #999;
}

#viewer-container {
    display: flex;
    justify-content: center;
    align-items: center; /* center the page vertically */
    min-height: 100%;
    position: relative;
    transition: transform 0.3s ease;
    padding: 24px 0 96px; /* space for top close and bottom controls */
}

#pdf-canvas {
    box-shadow: 0 10px 40px rgba(0,0,0,0.5);
    transition: transform 0.3s ease;
    border-radius: 6px;
    background-color: #fff;
}

/* Жаңа PDF зум контейнері */
.zoom-container { display: none !important; }

.zoom-button {
    width: 40px;
    height: 40px;
    border: none;
    background-color: transparent;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--pdf-text);
    font-size: 1.5rem;
    transition: background-color 0.2s;
}

.zoom-button:hover {
    background-color: var(--pdf-controls-hover);
}

.zoom-level {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: bold;
    color: var(--pdf-text);
    width: 60px;
}

.pdf-footer {
    position: fixed;
    left: 50%;
    bottom: max(16px, env(safe-area-inset-bottom) + 10px);
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 6px;
    background: rgba(0, 0, 0, 0.55);
    border: 1.5px solid rgba(255, 255, 255, 0.16);
    border-radius: 100px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.35);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    z-index: 1001;
}

.pdf-controls-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.pdf-footer .nav-btn {
    background: transparent;
    border: none;
    color: #fff;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    width: 46px;
    height: 46px;
    cursor: pointer;
    transition: background-color 0.18s ease, transform 0.1s ease;
}

.pdf-footer .nav-btn:hover:not(:disabled) { background: rgba(255, 255, 255, 0.15); }

.pdf-footer .nav-btn:active:not(:disabled) { transform: scale(0.9); }

.pdf-footer .nav-btn:disabled { opacity: 0.3; cursor: default; }

.pdf-footer .nav-btn svg { width: 23px; height: 23px; display: block; }

/* Масштабтау батырмалары */
.zoom-controls { display: none !important; }

.zoom-btn {
    background: var(--pdf-controls-bg);
    border: none;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.2rem;
    font-weight: bold;
    transition: background-color 0.2s;
}

.zoom-btn:hover {
    background-color: var(--pdf-controls-hover);
}

.zoom-info { display: none !important; }

/* Бет навигациясы — симметриялы орталық */
.page-info {
    display: flex;
    align-items: center;
    gap: 3px;
    justify-content: center;
    min-width: 78px;
    padding: 0 4px;
    font-size: 0.95rem;
    font-weight: 600;
    color: #fff;
}

#page-count { opacity: 0.65; }

.page-input {
    width: 40px;
    text-align: center;
    padding: 6px 2px;
    border-radius: 8px;
    border: none;
    font-size: 0.95rem;
    font-weight: 700;
    margin: 0 1px;
    background: rgba(255,255,255,0.14);
    color: #fff;
    transition: background 0.18s ease;
    box-shadow: none;
}

.page-input:hover { background: rgba(255,255,255,0.2); }

.page-input:focus {
    outline: none;
    background: rgba(255,255,255,0.24);
}

.page-count {
    margin-left: 5px;
}

/* Жүктеу индикаторы */
.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    padding: 50px;
    font-size: 1.2rem;
    color: #eee;
    position: absolute;
    top: 0;
    left: 0;
    background-color: rgba(0, 0, 0, 0.3);
    z-index: 5;
}

.spinner {
    border: 4px solid rgba(0,0,0,0.1);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border-left-color: var(--pdf-button-primary);
    margin-bottom: 15px;
    animation: spin 1s linear infinite;
}

@keyframes spin { 
    to { transform: rotate(360deg); } 
}

/* Прогресс индикатор стилі */
.progress-container {
    width: 100%;
    max-width: 300px;
    height: 8px;
    background-color: #f1f1f1;
    border-radius: 4px;
    margin: 15px 0;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--pdf-button-primary);
    border-radius: 4px;
    transition: width 0.3s ease;
}

#loading-progress {
    font-size: 0.95rem;
    font-weight: 700;
    color: rgba(255, 255, 255, 0.85);
    margin-top: 4px;
    letter-spacing: 0.02em;
}

/* ===== Жүктеу анимациясы — мөлдір (қара фонсыз), заманауи ===== */
#pdf-loader { background: transparent; }

#pdf-loader .loading-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 18px;
    padding: 0;
    background: transparent;
    border: none;
    box-shadow: none;
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
}

/* Жұмсақ із қалдыратын сақина + майда көлеңке (оқылуы үшін) */
#pdf-loader .spinner {
    width: 62px;
    height: 62px;
    border: none;
    border-radius: 50%;
    margin: 0;
    background: conic-gradient(from 90deg, transparent 0%, var(--pdf-button-primary, #4682B4) 88%, transparent 100%);
    -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 5px), #000 calc(100% - 5px));
    mask: radial-gradient(farthest-side, transparent calc(100% - 5px), #000 calc(100% - 5px));
    animation: spin 0.9s cubic-bezier(0.55, 0.15, 0.45, 0.85) infinite;
    filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.35));
}

#pdf-loader .loading-text {
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0.01em;
    margin: 0;
    text-shadow: 0 1px 5px rgba(0, 0, 0, 0.5);
    animation: pdf-load-pulse 1.4s ease-in-out infinite;
}

@keyframes pdf-load-pulse {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

#pdf-loader .progress-container {
    width: 200px;
    max-width: 60vw;
    height: 5px;
    background: rgba(255, 255, 255, 0.18);
    border-radius: 100px;
    overflow: hidden;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}

#pdf-loader .progress-bar {
    height: 100%;
    background: var(--pdf-button-primary, #4682B4);
    border-radius: 100px;
    transition: width 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

/* Мобильді құрылғылар үшін адаптивтік */
@media (max-width: 768px) {
    .reading-title {
        font-size: 2rem;
    }
    
    .subject-title {
        font-size: 1.5rem;
    }
    
    .books-grid {
        grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
        gap: 1.8rem;
    }
    
    .book-cover {
        height: 260px;
        padding: 18px;
    }
    
    .cover-title {
        font-size: 1.6rem;
    }
    
    .cover-title.long-title {
        font-size: 1.2rem;
    }
    
    .cover-title.very-long-title {
        font-size: 1.1rem;
    }
    
    .cover-grade {
        font-size: 0.9rem;
        padding: 6px 12px;
    }
    
    .cover-publisher {
        font-size: 0.95rem;
        padding: 6px 10px;
    }
    
    .pdf-modal-content { width: 100%; height: 100%; border-radius: 0; }
    
    .pdf-header {
        padding: 12px 15px;
    }
    
    .pdf-footer { gap: 10px; }
    
    .pdf-footer .nav-btn {
        width: 40px;
        height: 40px;
    }
    
    .page-info {
        font-size: 0.9rem;
    }
    
    .page-input {
        width: clamp(40px, 12vw, 64px);
        text-align: center;
        padding: 6px 10px;
    }

    .zoom-container { display: none; }
    
    .zoom-button {
        width: 36px;
        height: 36px;
    }
    
    /* Кішкентай экрандарда zoom панелі PDF үстінде көрсетілмейді */
    .zoom-controls {
        display: none;
    }
    
    /* Мобильді опциялар панелі көрсетіледі */
    .mobile-options {
        display: flex;
        position: fixed;
        bottom: 20px;
        right: 20px;
        background-color: rgba(255, 255, 255, 0.9);
        border-radius: 30px;
        padding: 8px;
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
        z-index: 1001;
    }
    
    /* PDF режимінде ғана көрсетіледі */
    .mobile-options {
        display: none;
    }
    
    .pdf-modal[style*="display: flex"] + .mobile-options {
        display: flex;
    }

    #pdf-canvas {
        width: 100% !important;
        height: auto !important;
        max-width: 100vw;
        image-rendering: -webkit-optimize-contrast;
        image-rendering: optimize-contrast;
        -ms-interpolation-mode: bicubic;
    }
    
    .pdf-viewer-content { padding: 10px; overflow-x: auto; }
    
    .reading-footer {
        margin-top: 40px;
        padding-top: 20px;
    }
    
    .reading-footer-text {
        font-size: 12px;
    }
}

/* Кішкентай мобильді құрылғылар үшін */
@media (max-width: 480px) {
    .reading-container {
        padding: 15px;
    }
    
    .subject-filters {
        gap: 8px;
        margin-bottom: 30px;
    }
    
    .filter-btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }
    
    .books-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 1.5rem;
    }
    
    .book-cover {
        height: 220px;
        padding: 15px;
    }
    
    .cover-title {
        font-size: 1.4rem;
    }
    
    .cover-title.long-title {
        font-size: 1.1rem;
    }
    
    .cover-title.very-long-title {
        font-size: 1rem;
    }
    
    .cover-grade {
        font-size: 0.85rem;
        padding: 5px 10px;
    }
    
    .cover-publisher {
        font-size: 0.85rem;
        padding: 5px 8px;
    }
    
    .book-details {
        padding: 15px 18px 18px 18px;
    }
    
    .book-details .authors {
        font-size: 0.85rem;
    }
    
    /* PDF просмотрщик на малых экранах */
    .pdf-body {
        padding: 10px 0;
    }
    
    .pdf-footer { grid-template-columns: auto auto auto; }
    
    .pdf-controls-group:last-child {
        margin-top: 5px;
        width: 100%;
        justify-content: center;
    }
}

/* Альбомный режим на телефонах */
@media (max-height: 500px) and (orientation: landscape) {
    .pdf-modal-content { height: 100%; width: 100%; border-radius: 0; }
    
    .pdf-header {
        padding: 8px 15px;
    }
    
    .pdf-footer { gap: 8px; }
    
    .pdf-footer .nav-btn {
        width: 36px;
        height: 36px;
    }
}