/* EPUB Reader / Viewer Layout and Themes */

/* Release EPUB Reader View from parent App-View transform containment bug on mobile */
#epubReaderView.app-view.active {
    transform: none !important;
}

#epubReaderMain {
    display: flex;
    width: 100%;
    height: 100vh;
    overflow: hidden;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 900;
    font-family: 'Inter', Georgia, serif;
    background: var(--reader-bg);
    color: var(--reader-text);
    transition: background 0.3s ease, color 0.3s ease;
    
    /* Theme Defaults - Light Mode */
    --reader-bg: #faf7f2;
    --reader-text: #2d2d2d;
    --reader-sidebar-bg: #f2ede2;
    --reader-border: #e3dbcb;
    --reader-muted: #7d7260;
    --reader-active-item: #eae1d0;
    --reader-font-size: 1.15rem;
}

/* Theme Configurations */
#epubReaderMain.theme-light {
    --reader-bg: #fcfbfa;
    --reader-text: #222222;
    --reader-sidebar-bg: #f5f4f0;
    --reader-border: #e6e5e0;
    --reader-muted: #70706b;
    --reader-active-item: #e8e7e1;
}

#epubReaderMain.theme-dark {
    --reader-bg: #141416;
    --reader-text: #e2e2e8;
    --reader-sidebar-bg: #1c1c1f;
    --reader-border: #2c2c35;
    --reader-muted: #888896;
    --reader-active-item: #282830;
}

#epubReaderMain.theme-sepia {
    --reader-bg: #f4ecd8;
    --reader-text: #5b4636;
    --reader-sidebar-bg: #eae0c7;
    --reader-border: #decfa9;
    --reader-muted: #8a735c;
    --reader-active-item: #dfd4b7;
}

#epubReaderMain.theme-bw {
    --reader-bg: #000000;
    --reader-text: #ffffff;
    --reader-sidebar-bg: #111111;
    --reader-border: #333333;
    --reader-muted: #aaaaaa;
    --reader-active-item: #222222;
}

/* Sidebar Styling */
#epubReaderSidebar {
    width: 300px;
    height: 100%;
    background: var(--reader-sidebar-bg);
    border-right: 1px solid var(--reader-border);
    display: flex;
    flex-direction: column;
    min-height: 0;
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.25, 1, 0.5, 1);
    flex-shrink: 0;
}

#epubReaderSidebar.collapsed {
    margin-left: -300px;
}

.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid var(--reader-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar-title {
    font-size: 1.15rem;
    font-weight: 700;
    margin: 0;
    color: var(--reader-text);
}

.toc-list {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 15px;
    list-style: none;
    margin: 0;
}

.toc-item {
    padding: 10px 14px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.95rem;
    margin-bottom: 6px;
    transition: all 0.2s ease;
    color: var(--reader-text);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.toc-item:hover {
    background: var(--reader-active-item);
}

.toc-item.active {
    background: var(--reader-active-item);
    font-weight: 700;
    border-left: 3px solid var(--primary, #00f5ff);
}

/* Content Panel Styling */
#epubReaderContentArea {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    position: relative;
}

#epubReaderHeader {
    height: 64px;
    border-bottom: 1px solid var(--reader-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 24px;
    background: var(--reader-bg);
    z-index: 10;
    
    /* Support safe area safe top padding on mobile screens with notches */
    padding-top: env(safe-area-inset-top, 0px);
    height: calc(64px + env(safe-area-inset-top, 0px));
}

.reader-header-left, .reader-header-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.reader-btn {
    background: transparent;
    border: 1px solid var(--reader-border);
    color: var(--reader-text);
    padding: 8px 14px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s ease;
}

.reader-btn:hover {
    background: var(--reader-active-item);
    border-color: var(--reader-text);
}

.reader-btn svg {
    width: 16px;
    height: 16px;
    stroke: currentColor;
    stroke-width: 2.2;
    fill: none;
}

/* Tool Panel / Options Dropdowns */
.reader-controls-dropdown {
    position: absolute;
    top: 70px;
    right: 24px;
    background: var(--reader-sidebar-bg);
    border: 1px solid var(--reader-border);
    border-radius: 12px;
    padding: 16px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    z-index: 20;
    display: none;
    flex-direction: column;
    gap: 14px;
    width: 280px;
    max-height: calc(100vh - 96px);
    overflow-y: auto;
    overscroll-behavior: contain;
    -webkit-overflow-scrolling: touch;
}

.reader-controls-dropdown.active {
    display: flex;
}

.control-group-title {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--reader-muted);
    letter-spacing: 0.05em;
    margin-bottom: 6px;
}

.theme-options {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
}

.theme-btn {
    height: 36px;
    border-radius: 8px;
    border: 2px solid transparent;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.8rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.theme-btn.light { background: #fcfbfa; color: #222222; }
.theme-btn.dark { background: #141416; color: #e2e2e8; }
.theme-btn.sepia { background: #f4ecd8; color: #5b4636; }
.theme-btn.bw { background: #000000; color: #ffffff; border-color: #333; }

.theme-btn.active {
    border-color: var(--primary, #00f5ff);
}

.layout-options {
    display: flex;
    gap: 8px;
}

.layout-btn {
    flex: 1;
    padding: 8px;
    border-radius: 8px;
    border: 1px solid var(--reader-border);
    background: transparent;
    color: var(--reader-text);
    cursor: pointer;
    font-weight: 600;
    text-align: center;
    font-size: 0.85rem;
}

.layout-btn.active {
    background: var(--reader-active-item);
    border-color: var(--primary, #00f5ff);
    font-weight: 700;
}

/* TTS Controls Section */
.tts-controls-section {
    border-top: 1px solid var(--reader-border);
    padding-top: 12px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.tts-sliders {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.slider-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
}

.slider-row input[type="range"] {
    flex: 1;
    margin-left: 12px;
    accent-color: var(--primary, #00f5ff);
}

.tts-buttons {
    display: flex;
    gap: 6px;
}

.tts-btn {
    flex: 1;
    padding: 6px;
    border-radius: 6px;
    border: 1px solid var(--reader-border);
    background: transparent;
    color: var(--reader-text);
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
}

.tts-btn:hover {
    background: var(--reader-active-item);
}

/* Main Font Families Mapping */
#epubReaderMain.font-sans { --reader-font-family: 'Inter', system-ui, -apple-system, sans-serif; }
#epubReaderMain.font-serif { --reader-font-family: Georgia, 'Times New Roman', serif; }
#epubReaderMain.font-mono { --reader-font-family: 'Fira Code', 'Courier New', monospace; }
#epubReaderMain.font-dyslexic { --reader-font-family: 'Comic Sans MS', cursive, sans-serif; }

#epubReaderMain {
    font-family: var(--reader-font-family, 'Inter', system-ui, sans-serif) !important;
}

#epubReaderContentBody {
    font-family: var(--reader-font-family, 'Inter', system-ui, sans-serif) !important;
}

/* Immersive Screen State */
#epubReaderMain.immersive-reading #epubReaderHeader,
#epubReaderMain.header-hidden #epubReaderHeader {
    display: none;
}

/* Main Reader Viewing Windows */
#epubReaderViewport {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden; /* Prevent horizontal scrolling layout breaks */
    position: relative;
    padding: 40px 24px;
    box-sizing: border-box;
    display: block; /* Native block layout handles vertical mouse wheel scrolling flawlessly */
    -webkit-overflow-scrolling: touch;
    overscroll-behavior-y: contain;
    touch-action: pan-y;
}

#epubReaderContentBody {
    width: 100%;
    max-width: 750px;
    line-height: 1.8;
    font-size: var(--reader-font-size, 1.15rem);
    box-sizing: border-box;
    margin: 0 auto; /* Horizontal alignment inside block layout */
    
    /* Strong word breaking to prevent long URLs from breaking layout */
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
}

#epubReaderContentBody img,
#epubReaderContentBody video,
#epubReaderContentBody svg {
    max-width: 100% !important;
    height: auto !important;
    object-fit: contain;
    display: block;
    margin: 0 auto;
}

#epubReaderContentBody pre,
#epubReaderContentBody table {
    max-width: 100% !important;
    overflow-x: auto;
    box-sizing: border-box;
}

#epubReaderContentBody p {
    margin-bottom: 1.6em;
    text-indent: 1.5em;
    text-align: justify;
}

/* Page Turn Layout Mode Override */
#epubReaderViewport.page-turn-mode {
    overflow-y: hidden;
    overflow-x: hidden;
    padding: 30px 48px;
}

#epubReaderViewport.page-turn-mode #epubReaderContentBody {
    column-fill: auto;
    column-width: 100%;
    column-gap: 48px;
    height: 100%;
    max-width: 100%;
    margin: 0;
    overflow-x: hidden;
    transition: transform 0.3s cubic-bezier(0.25, 1, 0.5, 1);
    display: block;
}

@media (min-width: 900px) {
    #epubReaderViewport.page-turn-mode #epubReaderContentBody {
        column-width: calc(50% - 24px); /* Display double column page on wide screens */
    }
}

/* Custom visual reading enhancements */
.tts-active-paragraph {
    background: rgba(0, 245, 255, 0.12);
    border-left: 4px solid var(--primary, #00f5ff);
    padding-left: 12px;
    margin-left: -16px !important;
    border-radius: 0 4px 4px 0;
    transition: all 0.25s ease;
}

/* Page Navigation Arrows for Page Turn mode */
.page-nav-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--reader-sidebar-bg);
    border: 1px solid var(--reader-border);
    color: var(--reader-text);
    display: none;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    transition: all 0.2s ease;
    z-index: 5;
}

#epubReaderViewport.page-turn-mode ~ .page-nav-arrow {
    display: flex;
}

.page-nav-arrow:hover {
    background: var(--reader-active-item);
    transform: translateY(-50%) scale(1.08);
}

.page-nav-arrow.left { left: 12px; }
.page-nav-arrow.right { right: 12px; }

.page-nav-arrow svg {
    width: 20px;
    height: 20px;
    stroke: currentColor;
    stroke-width: 2.5;
    fill: none;
}

/* Reader Footer Navigation */
#epubReaderFooter {
    height: 48px;
    border-top: 1px solid var(--reader-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 24px;
    background: var(--reader-bg);
    font-size: 0.85rem;
    color: var(--reader-muted);
}

/* Reader Cover page rendering */
.reader-cover-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    text-align: center;
    padding: 40px;
    box-sizing: border-box;
    width: 100%;
    max-width: 100%;
    overflow: hidden;
}

.reader-cover-img {
    max-height: 60vh;
    max-width: 100%;
    border-radius: 12px;
    box-shadow: 0 8px 30px rgba(0,0,0,0.3);
    margin-bottom: 24px;
}

.reader-cover-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 8px;
    box-sizing: border-box;
    max-width: 100%;
    word-wrap: break-word;
    word-break: break-word;
    overflow-wrap: break-word;
}

.reader-cover-author {
    font-size: 1.25rem;
    color: var(--reader-muted);
}

/* Chapter Scroll Divider for Continuous Reading */
.chapter-scroll-divider {
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 80px 0 50px;
    position: relative;
    text-align: center;
    width: 100%;
    box-sizing: border-box;
}

.chapter-scroll-divider::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--reader-border) 20%, var(--reader-border) 80%, transparent);
    z-index: 1;
}

.chapter-scroll-divider span {
    background: var(--reader-bg);
    padding: 8px 24px;
    color: var(--primary, #00f5ff);
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    position: relative;
    z-index: 2;
    border: 1px solid var(--reader-border);
    border-radius: 20px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    transition: background 0.3s ease, border-color 0.3s ease;
}

/* Mobile Sidebar Backdrop Overlay */
#epubReaderSidebarOverlay {
    display: none;
}

/* Mobile View Optimizations for Ebook Reader */
@media (max-width: 768px) {
    /* 1. Sidebar overlay drawer styling & backdrop overlay */
    #epubReaderSidebar {
        position: fixed;
        top: 0;
        left: 0;
        width: 280px !important;
        height: 100%;
        min-height: 100dvh;
        z-index: 9990 !important; /* Overlay absolutely on top of everything */
        box-shadow: 5px 0 25px rgba(0, 0, 0, 0.4);
        max-width: 85vw; /* Don't cover entire screen, leave edge to click out */
        transform: translateX(0);
        transition: transform 0.3s cubic-bezier(0.25, 1, 0.5, 1);
    }

    .toc-list {
        padding-bottom: calc(24px + env(safe-area-inset-bottom, 0px));
    }

    /* Force solid non-transparent background-colors for each theme on mobile */
    #epubReaderMain.theme-light #epubReaderSidebar {
        background-color: #f5f4f0 !important;
        background: #f5f4f0 !important;
    }
    #epubReaderMain.theme-dark #epubReaderSidebar {
        background-color: #1c1c1f !important;
        background: #1c1c1f !important;
    }
    #epubReaderMain.theme-sepia #epubReaderSidebar {
        background-color: #eae0c7 !important;
        background: #eae0c7 !important;
    }
    #epubReaderMain.theme-bw #epubReaderSidebar {
        background-color: #111111 !important;
        background: #111111 !important;
    }

    #epubReaderSidebar.collapsed {
        transform: translateX(-100%) !important;
        margin-left: 0 !important; /* Override desktop margin-left */
    }

    #epubReaderSidebarOverlay {
        display: block;
        position: fixed;
        top: 0;
        left: 0;
        width: 100vw;
        height: 100vh;
        background: rgba(0, 0, 0, 0.6) !important;
        z-index: 9980 !important; /* Positioned directly under sidebar */
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.3s ease;
    }

    #epubReaderSidebarOverlay.active {
        opacity: 1;
        pointer-events: auto;
    }

    #epubReaderSidebarOverlay,
    #readerExitImmersiveBtn,
    #readerShowHeaderBtn {
        backdrop-filter: none !important;
    }

    /* 2. Header layout simplification on small screens */
    #epubReaderHeader {
        padding: 0 12px;
        padding-top: env(safe-area-inset-top, 0px);
        height: calc(56px + env(safe-area-inset-top, 0px));
    }

    .reader-header-left, .reader-header-right {
        gap: 8px;
    }

    #readerCurrentChapterName {
        font-size: 0.9rem;
        max-width: 110px !important;
    }

    /* Hide text labels on header buttons, leaving clean and intuitive icons */
    #readerBackBtn {
        padding: 8px;
        font-size: 0 !important; /* Hides the "Home" text */
    }
    #readerBackBtn svg {
        margin-right: 0 !important;
        width: 20px;
        height: 20px;
    }

    #readerToggleSidebarTrigger {
        padding: 8px;
        font-size: 0 !important; /* Hides "TOC" text */
    }
    #readerToggleSidebarTrigger svg {
        width: 20px;
        height: 20px;
    }

    /* Target the file upload label inside header */
    label[for="epubReaderUploadInput"] {
        padding: 8px;
        font-size: 0 !important; /* Hides "Open Local EPUB" text */
    }
    label[for="epubReaderUploadInput"] svg {
        margin-right: 0 !important;
        width: 20px;
        height: 20px;
    }

    #readerSettingsBtn {
        padding: 8px;
    }
    #readerSettingsBtn svg {
        width: 20px;
        height: 20px;
    }

    /* 3. Dropdown Controls Dialog */
    .reader-controls-dropdown {
        top: 62px;
        right: 12px;
        width: calc(100% - 24px);
        max-width: 320px;
        padding: 12px;
        box-sizing: border-box;
    }

    /* 4. Viewport padding optimizations */
    #epubReaderViewport {
        padding: 24px 16px;
        -webkit-overflow-scrolling: touch;
        scroll-behavior: auto;
    }

    #epubReaderMain,
    #epubReaderViewport,
    #epubReaderContentBody {
        will-change: auto;
    }

    #epubReaderContentBody {
        font-size: var(--reader-font-size, 1.05rem); /* Slightly smaller default base font on mobile */
    }

    #epubReaderContentBody p {
        text-align: left; /* Avoid awkward word justification gaps on narrow mobile screens */
        text-indent: 1em;
        margin-bottom: 1.2em;
    }

    /* 5. Page Turn Viewport layout on mobile */
    #epubReaderViewport.page-turn-mode {
        padding: 20px 16px;
    }

    #epubReaderViewport.page-turn-mode #epubReaderContentBody {
        column-count: 1 !important;
        column-width: auto !important;
        column-gap: 16px !important;
    }

    /* Hide the huge desktop side nav arrows on mobile since clicking screen margins or footer works much better */
    .page-nav-arrow {
        display: none !important;
    }

    /* 6. Footer layout optimization */
    #epubReaderFooter {
        height: 40px;
        padding: 0 12px;
        font-size: 0.75rem;
    }

    /* 7. Cover page image scale */
    .reader-cover-container {
        padding: 20px;
    }

    .reader-cover-img {
        max-height: 45vh;
    }

    .reader-cover-title {
        font-size: 1.5rem;
    }
}

/* TTS Mode Active Text Selection & Hover Styles */
.tts-mode-active p,
.tts-mode-active h1,
.tts-mode-active h2,
.tts-mode-active h3,
.tts-mode-active h4,
.tts-mode-active li,
.tts-mode-active blockquote {
    cursor: pointer !important;
    transition: background-color 0.2s ease, border-left-color 0.2s ease;
}

.tts-mode-active p:hover,
.tts-mode-active h1:hover,
.tts-mode-active h2:hover,
.tts-mode-active h3:hover,
.tts-mode-active h4:hover,
.tts-mode-active li:hover,
.tts-mode-active blockquote:hover {
    background-color: rgba(0, 245, 255, 0.05);
}