/* On Trust and AI — online reader (paper/sepia design system) */

/* ── Theme tokens ─────────────────────────────────────────────── */
.book-reader-app[data-theme="paper"],
.book-reader-body.book-reader-gate-body {
    --rd-bg: oklch(0.972 0.012 82);
    --rd-chrome-bg: oklch(0.98 0.01 82);
    --rd-fg: oklch(0.22 0.012 60);
    --rd-muted: oklch(0.52 0.012 70);
    --rd-hairline: oklch(0.88 0.012 75);
    --rd-accent: oklch(0.55 0.13 45);
    --rd-accent-soft: oklch(0.94 0.045 50);
    --rd-body-font: "Source Serif 4", "Source Serif Pro", Georgia, serif;
    --rd-ui-font: "Inter", system-ui, -apple-system, sans-serif;
    --rd-mono-font: "JetBrains Mono", ui-monospace, monospace;
    --rd-font-scale: 1;
}

.book-reader-app[data-theme="sepia"] {
    --rd-bg: oklch(0.93 0.028 78);
    --rd-chrome-bg: oklch(0.94 0.025 78);
    --rd-fg: oklch(0.26 0.018 55);
    --rd-muted: oklch(0.50 0.022 60);
    --rd-hairline: oklch(0.84 0.022 70);
    --rd-accent: oklch(0.55 0.13 45);
    --rd-accent-soft: oklch(0.90 0.055 50);
}

/* ── Page shell ───────────────────────────────────────────────── */
.book-reader-body {
    margin: 0;
    background: var(--rd-bg, oklch(0.972 0.012 82));
    color: var(--rd-fg, oklch(0.22 0.012 60));
    font-family: var(--rd-body-font, Georgia, serif);
    overflow: hidden;
    height: 100dvh;
    -webkit-font-smoothing: antialiased;
}

.book-reader-body:not(.book-reader-gate-body) {
    overflow: hidden;
}

/* ── Gate / denied pages ──────────────────────────────────────── */
.book-reader-gate-body {
    --rd-bg: oklch(0.972 0.012 82);
    --rd-fg: oklch(0.22 0.012 60);
    --rd-muted: oklch(0.52 0.012 70);
    --rd-hairline: oklch(0.88 0.012 75);
    --rd-accent: oklch(0.55 0.13 45);
    --rd-accent-soft: oklch(0.94 0.045 50);
    --rd-body-font: "Source Serif 4", "Source Serif Pro", Georgia, serif;
    --rd-ui-font: "Inter", system-ui, sans-serif;
}

.book-reader-denied {
    min-height: 100dvh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: max(1.5rem, env(safe-area-inset-top)) 1.5rem max(1.5rem, env(safe-area-inset-bottom));
    background: var(--rd-bg);
}

.book-reader-denied-card {
    background: var(--rd-chrome-bg, var(--rd-bg));
    border: 1px solid var(--rd-hairline);
    border-radius: 12px;
    padding: 2rem 1.75rem;
    max-width: 420px;
    width: 100%;
    text-align: center;
    box-shadow: 0 18px 40px -12px rgba(40, 28, 12, 0.12);
}

.book-reader-denied-card h1 {
    font-family: var(--rd-body-font);
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--rd-fg);
    margin: 0 0 0.75rem;
}

.book-reader-denied-card p {
    font-family: var(--rd-ui-font);
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--rd-muted);
    margin: 0 0 0.75rem;
}

.book-reader-denied-card a {
    color: var(--rd-accent);
    text-decoration: none;
}

.book-reader-denied-card a:hover {
    text-decoration: underline;
}

.book-reader-gate-card {
    max-width: 480px;
    text-align: left;
}

.book-reader-gate-card h1 {
    text-align: center;
    font-size: 1.5rem;
    line-height: 1.25;
    margin-bottom: 0.75rem;
}

.book-reader-gate-card h1 em {
    font-style: italic;
}

.book-reader-gate-lead {
    font-family: var(--rd-ui-font);
    color: var(--rd-muted);
    font-size: 0.92rem;
    line-height: 1.65;
    margin-bottom: 1.25rem;
}

.book-reader-gate-error {
    background: oklch(0.95 0.04 25);
    border: 1px solid oklch(0.85 0.08 25);
    color: oklch(0.45 0.12 25);
    border-radius: 8px;
    padding: 0.65rem 0.85rem;
    font-family: var(--rd-ui-font);
    font-size: 0.85rem;
    margin-bottom: 1rem;
}

.book-reader-gate-form label {
    display: block;
    font-family: var(--rd-ui-font);
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--rd-muted);
    margin-bottom: 0.4rem;
}

.book-reader-gate-form input[type="text"] {
    width: 100%;
    box-sizing: border-box;
    padding: 0.7rem 0.85rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 8px;
    font-size: 0.88rem;
    font-family: var(--rd-mono-font, ui-monospace, monospace);
    background: var(--rd-bg);
    color: var(--rd-fg);
    margin-bottom: 0.85rem;
}

.book-reader-gate-form input[type="text"]:focus {
    outline: 2px solid var(--rd-accent);
    outline-offset: 1px;
    border-color: var(--rd-accent);
}

.book-reader-gate-submit {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--rd-fg);
    color: var(--rd-bg);
    border: none;
    border-radius: 999px;
    font-family: var(--rd-ui-font);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: opacity 0.15s;
}

.book-reader-gate-submit:hover {
    opacity: 0.88;
}

.book-reader-gate-help,
.book-reader-gate-back {
    font-family: var(--rd-ui-font);
    font-size: 0.82rem;
    color: var(--rd-muted);
    line-height: 1.55;
    margin-top: 1rem;
}

.book-reader-gate-help a,
.book-reader-gate-back a {
    color: var(--rd-accent);
}

.book-reader-gate-section {
    margin-bottom: 0.25rem;
}

.book-reader-gate-section-label {
    font-family: var(--rd-ui-font);
    font-size: 0.68rem;
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--rd-accent);
    margin: 0 0 0.35rem;
}

.book-reader-gate-divider {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin: 1.1rem 0;
    color: var(--rd-muted);
    font-family: var(--rd-ui-font);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.book-reader-gate-divider::before,
.book-reader-gate-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--rd-hairline);
}

.book-reader-gate-notice {
    border-radius: 8px;
    padding: 0.75rem 0.9rem;
    font-family: var(--rd-ui-font);
    font-size: 0.85rem;
    line-height: 1.55;
}

.book-reader-gate-notice-pending {
    background: oklch(0.96 0.03 85);
    border: 1px solid oklch(0.88 0.06 80);
    color: var(--rd-fg);
}

.book-reader-gate-notice strong {
    display: block;
    margin-bottom: 0.25rem;
}

.book-reader-gate-field-hint {
    font-family: var(--rd-ui-font);
    font-size: 0.75rem;
    color: var(--rd-muted);
    margin: -0.5rem 0 0.85rem;
}

.book-reader-verify-form textarea,
.book-reader-verify-form input[type="file"],
.book-reader-verify-form input[type="date"] {
    width: 100%;
    box-sizing: border-box;
    padding: 0.7rem 0.85rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 8px;
    font-size: 0.88rem;
    font-family: var(--rd-ui-font);
    background: var(--rd-bg);
    color: var(--rd-fg);
    margin-bottom: 0.85rem;
}

.book-reader-verify-card {
    max-width: 520px;
}

.book-reader-gate-alt {
    margin-top: 1.25rem;
    padding-top: 1rem;
    border-top: 1px solid var(--rd-hairline);
}

.book-reader-gate-alt-title {
    font-family: var(--rd-ui-font);
    font-size: 0.68rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--rd-muted);
    margin: 0 0 0.5rem;
}

.book-reader-gate-alt-list {
    margin: 0;
    padding-left: 1.1rem;
    font-family: var(--rd-ui-font);
    font-size: 0.85rem;
    color: var(--rd-muted);
    line-height: 1.65;
}

/* ── Reader app layout ─────────────────────────────────────────── */
.book-reader-app {
    display: flex;
    flex-direction: row;
    height: 100dvh;
    max-height: 100dvh;
    background: var(--rd-bg);
    color: var(--rd-fg);
    font-family: var(--rd-body-font);
    overflow: hidden;
}

.reader-surface {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    position: relative;
    background: var(--rd-bg);
}

/* ── Desktop sidebar ───────────────────────────────────────────── */
.reader-sidebar {
    display: none;
    flex-direction: column;
    width: 280px;
    flex-shrink: 0;
    border-right: 1px solid var(--rd-hairline);
    background: var(--rd-bg);
    font-family: var(--rd-ui-font);
    overflow: hidden;
}

@media (min-width: 1024px) {
    .reader-sidebar {
        display: flex;
    }

    .reader-toc-mobile {
        display: none !important;
    }
}

.reader-sidebar-header {
    padding: 1.5rem 1.375rem 1.125rem;
    flex-shrink: 0;
}

.reader-sidebar-kicker,
.reader-sheet-kicker {
    font-size: 0.66rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--rd-muted);
    margin-bottom: 0.35rem;
}

.reader-sidebar-title {
    font-family: var(--rd-body-font);
    font-size: 1.0625rem;
    line-height: 1.25;
    font-weight: 600;
    color: var(--rd-fg);
}

.reader-sidebar-author {
    font-family: var(--rd-body-font);
    font-style: italic;
    font-size: 0.78rem;
    color: var(--rd-muted);
    margin-top: 0.25rem;
}

.reader-toc-list {
    flex: 1;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 0.5rem 0 1rem;
}

.reader-toc-item {
    display: block;
    width: 100%;
    padding: 0.75rem 1.375rem;
    border: none;
    border-left: 2px solid transparent;
    background: transparent;
    cursor: pointer;
    text-align: left;
    font-family: inherit;
    color: inherit;
    transition: background 0.12s;
}

.reader-toc-item:hover {
    background: var(--rd-accent-soft);
}

.reader-toc-item.is-current {
    border-left-color: var(--rd-accent);
    background: var(--rd-accent-soft);
}

.reader-toc-item-label {
    font-family: var(--rd-body-font);
    font-size: 0.875rem;
    line-height: 1.3;
    color: var(--rd-fg);
}

.reader-toc-item.is-current .reader-toc-item-label {
    font-weight: 600;
}

/* ── Top bar ───────────────────────────────────────────────────── */
.reader-topbar {
    position: relative;
    flex-shrink: 0;
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 0.75rem;
    padding: max(0.875rem, env(safe-area-inset-top)) 1rem 0.75rem;
    padding-left: max(1rem, env(safe-area-inset-left));
    padding-right: max(1rem, env(safe-area-inset-right));
    background: var(--rd-bg);
    border-bottom: 1px solid var(--rd-hairline);
    font-family: var(--rd-ui-font);
    z-index: 5;
}

@media (min-width: 640px) {
    .reader-topbar {
        padding-top: 0.875rem;
        padding-left: 1.375rem;
        padding-right: 1.375rem;
    }
}

.reader-topbar-center {
    min-width: 0;
    text-align: center;
}

.reader-chapter-num {
    display: none;
}

.reader-chapter-title {
    font-family: var(--rd-body-font);
    font-size: 0.78rem;
    font-weight: 500;
    color: var(--rd-fg);
    margin-top: 0.0625rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

@media (min-width: 640px) {
    .reader-chapter-title {
        font-size: 0.84rem;
    }
}

.reader-topbar-actions {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.reader-icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    padding: 0;
    border: none;
    border-radius: 0.5rem;
    background: transparent;
    color: var(--rd-fg);
    cursor: pointer;
    text-decoration: none;
    flex-shrink: 0;
}

.reader-icon-btn:hover {
    background: var(--rd-accent-soft);
}

.reader-progress-strip {
    position: absolute;
    left: 0;
    right: 0;
    bottom: -1px;
    height: 1px;
    background: var(--rd-hairline);
    pointer-events: none;
}

.reader-progress-fill {
    height: 100%;
    background: var(--rd-accent);
    opacity: 0.85;
    transition: width 0.12s ease-out;
}

/* ── Main reading area ─────────────────────────────────────────── */
.reader-main {
    flex: 1;
    min-height: 0;
    position: relative;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.reader-loading,
.reader-error {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    font-family: var(--rd-ui-font);
    font-size: 0.9rem;
    color: var(--rd-muted);
    z-index: 2;
    pointer-events: none;
    padding: 0 1.5rem;
}

.reader-error {
    color: oklch(0.45 0.12 25);
}

.reader-content {
    flex: 1;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    box-sizing: border-box;
    width: 100%;
    max-width: none;
    margin: 0;
    padding: 1.75rem clamp(1.375rem, 4vw, 3.5rem) 5rem;
    color: var(--rd-fg);
    font-family: var(--rd-body-font);
    font-size: calc(1.03125rem * var(--rd-font-scale, 1));
    line-height: 1.68;
    hyphens: auto;
    text-wrap: pretty;
}

@media (min-width: 640px) {
    .reader-content {
        font-size: calc(1.125rem * var(--rd-font-scale, 1));
    }
}

@media (min-width: 1024px) {
    .reader-content {
        padding-top: 2.75rem;
        font-size: calc(1.1875rem * var(--rd-font-scale, 1));
    }
}

.reader-content img {
    max-width: 100%;
    height: auto;
    cursor: zoom-in;
}

.reader-content h1,
.reader-content h2,
.reader-content h3,
.reader-content h4 {
    font-family: var(--rd-body-font);
    line-height: 1.25;
    margin: 1.5rem 0 0.75rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.reader-content p {
    margin: 0 0 1.1em;
    text-align: justify;
}

.reader-content a {
    color: var(--rd-accent);
}

.reader-content blockquote {
    margin: 1.6em 0;
    padding-left: 1rem;
    border-left: 2px solid var(--rd-accent);
    font-style: italic;
}

/* Tables: white cell canvas in paper/sepia (EPUB highlights assume a white base).
   Layered so unlayered EPUB stylesheet rules for colored cells still win. */
@layer reader-epub-tables {
    .book-reader-app[data-theme="paper"] .reader-content table,
    .book-reader-app[data-theme="sepia"] .reader-content table,
    .book-reader-app[data-theme="paper"] .reader-spread-content table,
    .book-reader-app[data-theme="sepia"] .reader-spread-content table,
    .book-reader-app[data-theme="paper"] .reader-content table thead,
    .book-reader-app[data-theme="paper"] .reader-content table tbody,
    .book-reader-app[data-theme="sepia"] .reader-content table thead,
    .book-reader-app[data-theme="sepia"] .reader-content table tbody,
    .book-reader-app[data-theme="paper"] .reader-spread-content table thead,
    .book-reader-app[data-theme="paper"] .reader-spread-content table tbody,
    .book-reader-app[data-theme="sepia"] .reader-spread-content table thead,
    .book-reader-app[data-theme="sepia"] .reader-spread-content table tbody,
    .book-reader-app[data-theme="paper"] .reader-content table tr,
    .book-reader-app[data-theme="sepia"] .reader-content table tr,
    .book-reader-app[data-theme="paper"] .reader-spread-content table tr,
    .book-reader-app[data-theme="sepia"] .reader-spread-content table tr {
        background-color: #fff;
    }

    .book-reader-app[data-theme="paper"] .reader-content table td:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="paper"] .reader-content table th:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="sepia"] .reader-content table td:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="sepia"] .reader-content table th:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="paper"] .reader-spread-content table td:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="paper"] .reader-spread-content table th:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="sepia"] .reader-spread-content table td:not([style*="background"]):not([bgcolor]),
    .book-reader-app[data-theme="sepia"] .reader-spread-content table th:not([style*="background"]):not([bgcolor]) {
        background-color: #fff;
    }
}

.reader-chapter-loading {
    text-align: center;
    font-family: var(--rd-ui-font);
    color: var(--rd-muted);
    padding: 2rem 1rem;
}

/* ── Bottom bar ────────────────────────────────────────────────── */
.reader-bottombar {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.625rem 1.125rem max(1rem, env(safe-area-inset-bottom));
    padding-left: max(1.125rem, env(safe-area-inset-left));
    padding-right: max(1.125rem, env(safe-area-inset-right));
    border-top: 1px solid var(--rd-hairline);
    background: var(--rd-bg);
    font-family: var(--rd-ui-font);
    font-size: 0.6875rem;
    letter-spacing: 0.04em;
    color: var(--rd-muted);
    z-index: 5;
}

@media (min-width: 640px) {
    .reader-bottombar {
        padding-bottom: 1rem;
        padding-left: 1.5rem;
        padding-right: 1.5rem;
    }
}

.reader-bottombar-nav {
    display: none;
    flex: 0 0 4.75rem;
    border: none;
    background: transparent;
    padding: 0.35rem 0;
    font-family: var(--rd-ui-font);
    font-size: 0.6875rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    color: var(--rd-muted);
    cursor: pointer;
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    transition: color 0.12s;
}

.reader-bottombar-nav:hover:not(.is-unavailable),
.reader-bottombar-nav:focus-visible:not(.is-unavailable) {
    color: var(--rd-fg);
    outline: none;
}

.reader-bottombar-nav:focus-visible:not(.is-unavailable) {
    outline: 2px solid var(--rd-accent);
    outline-offset: 2px;
    border-radius: 4px;
}

.reader-bottombar-nav.is-unavailable {
    visibility: hidden;
    pointer-events: none;
}

.reader-bottombar-prev {
    text-align: left;
}

.reader-bottombar-next {
    text-align: right;
}

.reader-bottombar-center {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-width: 0;
}

@media (max-width: 1023px) {
    .reader-bottombar {
        gap: 0.5rem;
    }

    .reader-bottombar-nav {
        display: block;
    }

    .reader-bottombar-center {
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 0.15rem;
        text-align: center;
    }

    .reader-min-left {
        flex: none;
        text-align: center;
        white-space: normal;
    }

    .reader-progress-pct {
        margin-left: 0;
    }
}

@media (min-width: 1024px) {
    .reader-bottombar-nav {
        display: none !important;
    }
}

.reader-min-left {
    flex: 1;
    min-width: 0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.reader-progress-pct {
    font-family: var(--rd-mono-font);
    font-size: 0.66rem;
    letter-spacing: 0.08em;
    flex-shrink: 0;
    margin-left: 0.75rem;
}

/* ── Overlay sheets (mobile TOC, settings) ─────────────────────── */
.reader-overlays {
    position: absolute;
    inset: 0;
    z-index: 100;
    pointer-events: none;
}

.reader-overlays:not([hidden]) {
    pointer-events: auto;
}

.reader-overlays[hidden] {
    display: none !important;
}

.reader-overlay-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(40, 28, 12, 0.35);
    z-index: 0;
    pointer-events: auto;
    animation: rd-fade-in 0.2s ease;
}

.reader-toc-sheet,
.reader-settings-sheet {
    position: absolute;
    inset: 0;
    z-index: 1;
    display: flex;
    flex-direction: column;
    background: var(--rd-bg);
    font-family: var(--rd-ui-font);
    animation: rd-slide-up 0.24s cubic-bezier(0.2, 0.9, 0.3, 1);
    overflow: hidden;
    pointer-events: auto;
}

.reader-toc-sheet[hidden],
.reader-settings-sheet[hidden] {
    display: none !important;
    pointer-events: none !important;
}

@media (min-width: 1024px) {
    .reader-toc-sheet {
        display: none !important;
    }
}

.reader-sheet-header {
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: max(0.875rem, env(safe-area-inset-top)) 1.125rem 0.75rem;
    border-bottom: 1px solid var(--rd-hairline);
    flex-shrink: 0;
}

.reader-sheet-close {
    position: relative;
    z-index: 3;
    min-width: 2.75rem;
    min-height: 2.75rem;
    touch-action: manipulation;
}

.reader-sheet-close svg {
    pointer-events: none;
}

.reader-sheet-book {
    padding: 1.25rem 1.375rem 0.875rem;
    flex-shrink: 0;
}

.reader-toc-list-sheet {
    flex: 1;
    overflow-y: auto;
}

/* Settings sheet */
.reader-settings-sheet {
    max-width: 100%;
}

@media (min-width: 480px) {
    .reader-settings-sheet {
        inset: auto;
        top: auto;
        left: 50%;
        bottom: 0;
        transform: translateX(-50%);
        width: min(420px, 100%);
        max-height: 70dvh;
        border-radius: 16px 16px 0 0;
        border: 1px solid var(--rd-hairline);
        box-shadow: 0 -18px 40px -12px rgba(40, 28, 12, 0.18);
    }
}

.reader-settings-body {
    padding: 1.25rem 1.375rem 1.5rem;
    overflow-y: auto;
}

.reader-settings-group {
    border: none;
    margin: 0 0 1.25rem;
    padding: 0;
}

.reader-settings-group legend {
    font-size: 0.66rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--rd-muted);
    margin-bottom: 0.65rem;
    padding: 0;
}

.reader-settings-options {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.reader-settings-chip {
    padding: 0.5rem 1rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 999px;
    background: var(--rd-bg);
    color: var(--rd-fg);
    font-family: var(--rd-ui-font);
    font-size: 0.8125rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.12s, border-color 0.12s;
}

.reader-settings-chip:hover {
    border-color: var(--rd-muted);
}

.reader-settings-chip.is-active {
    background: var(--rd-fg);
    color: var(--rd-bg);
    border-color: var(--rd-fg);
}

/* ── Animations ────────────────────────────────────────────────── */
@keyframes rd-slide-up {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes rd-fade-in {
    from { opacity: 0; }
    to { opacity: 1; }
}

@media (min-width: 480px) {
    .reader-settings-sheet {
        animation: rd-slide-up-sheet 0.22s cubic-bezier(0.2, 0.9, 0.3, 1);
    }

    @keyframes rd-slide-up-sheet {
        from {
            opacity: 0;
            transform: translateX(-50%) translateY(100%);
        }
        to {
            opacity: 1;
            transform: translateX(-50%) translateY(0);
        }
    }
}

/* Lock scroll and ignore pointer events on reading surface while overlay open */
.book-reader-app.reader-overlay-open .reader-main,
.book-reader-app.reader-overlay-open .reader-topbar,
.book-reader-app.reader-overlay-open .reader-bottombar {
    pointer-events: none;
}

.book-reader-app.reader-overlay-open .reader-content {
    overflow: hidden;
}

/* ── Image zoom modal ─────────────────────────────────────────── */
.reader-image-zoom {
    position: fixed;
    inset: 0;
    z-index: 200;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: center;
    background: rgba(28, 20, 10, 0.88);
    animation: rd-fade-in 0.18s ease;
    touch-action: none;
}

.reader-image-zoom[hidden] {
    display: none !important;
}

.reader-image-zoom-close {
    position: absolute;
    top: max(0.75rem, env(safe-area-inset-top));
    right: max(0.75rem, env(safe-area-inset-right));
    z-index: 2;
    color: oklch(0.92 0.02 75);
    background: rgba(40, 28, 12, 0.45);
    border: 1px solid rgba(255, 248, 235, 0.2);
    min-width: 2.75rem;
    min-height: 2.75rem;
    touch-action: manipulation;
}

.reader-image-zoom-close:hover {
    background: rgba(40, 28, 12, 0.65);
}

.reader-image-zoom-close svg {
    pointer-events: none;
}

.reader-image-zoom-stage {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 0;
    padding: max(3.25rem, env(safe-area-inset-top)) max(0.75rem, env(safe-area-inset-right))
        max(1rem, env(safe-area-inset-bottom)) max(0.75rem, env(safe-area-inset-left));
    overflow: hidden;
    touch-action: none;
    cursor: grab;
}

.reader-image-zoom-stage.is-dragging {
    cursor: grabbing;
}

.reader-image-zoom-img {
    display: block;
    max-width: none;
    max-height: none;
    width: auto;
    height: auto;
    transform-origin: center center;
    will-change: transform;
    user-select: none;
    -webkit-user-drag: none;
    pointer-events: none;
}

.reader-image-zoom-stage.is-zoomed {
    cursor: grab;
}

.book-reader-body.reader-image-zoom-open {
    overflow: hidden;
}

.book-reader-app.reader-image-zoom-open .reader-content {
    overflow: hidden;
}

/* ── Footnote reference links ───────────────────────────────────── */
.reader-content sup a[href^="#"] {
    cursor: pointer;
    text-decoration: none;
    color: var(--rd-accent);
    font-weight: 600;
    font-size: 0.78em;
    line-height: 0;
    vertical-align: super;
    padding: 0 0.12em;
    border-radius: 0.2em;
    transition: background 0.12s, color 0.12s;
}

.reader-content sup a[href^="#"]:hover {
    text-decoration: underline;
    background: var(--rd-accent-soft);
}

/* ── Footnote modal ─────────────────────────────────────────────── */
.reader-footnote-modal {
    position: fixed;
    inset: 0;
    z-index: 190;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: max(1rem, env(safe-area-inset-top)) max(1rem, env(safe-area-inset-right))
        max(1rem, env(safe-area-inset-bottom)) max(1rem, env(safe-area-inset-left));
    pointer-events: none;
}

.reader-footnote-modal[hidden] {
    display: none !important;
}

.reader-footnote-modal:not([hidden]) {
    pointer-events: auto;
}

.reader-footnote-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(40, 28, 12, 0.38);
    animation: rd-fade-in 0.18s ease;
}

.reader-footnote-card {
    position: relative;
    z-index: 1;
    width: min(34rem, 100%);
    max-height: min(70dvh, 28rem);
    display: flex;
    flex-direction: column;
    background: var(--rd-bg);
    color: var(--rd-fg);
    border: 1px solid var(--rd-hairline);
    border-radius: 12px;
    box-shadow: 0 18px 40px -12px rgba(40, 28, 12, 0.22);
    animation: rd-fade-in 0.2s ease;
    overflow: hidden;
}

.reader-footnote-close {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    z-index: 2;
    min-width: 2.75rem;
    min-height: 2.75rem;
    touch-action: manipulation;
}

.reader-footnote-close svg {
    pointer-events: none;
}

.reader-footnote-label {
    flex-shrink: 0;
    padding: 1rem 3rem 0 1.25rem;
    font-family: var(--rd-mono-font);
    font-size: 0.72rem;
    letter-spacing: 0.08em;
    color: var(--rd-muted);
}

.reader-footnote-body {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 0.25rem 1.25rem 1.25rem;
    font-family: var(--rd-body-font);
    font-size: calc(0.95rem * var(--rd-font-scale, 1));
    line-height: 1.62;
}

.reader-footnote-body:only-child,
.reader-footnote-label[hidden] + .reader-footnote-body {
    padding-top: 2.75rem;
}

.reader-footnote-body p {
    margin: 0 0 0.85em;
    text-align: left;
}

.reader-footnote-body a {
    color: var(--rd-accent);
    word-break: break-word;
}

.book-reader-body.reader-footnote-open {
    overflow: hidden;
}

.book-reader-app.reader-footnote-open .reader-content {
    overflow: hidden;
}

/* ── Text selection menu ─────────────────────────────────────────── */
@keyframes rd-pop {
    from {
        opacity: 0;
        transform: translate(-50%, -100%) scale(0.92);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -100%) scale(1);
    }
}

@keyframes rd-pop-below {
    from {
        opacity: 0;
        transform: translate(-50%, 12px) scale(0.92);
    }
    to {
        opacity: 1;
        transform: translate(-50%, 12px) scale(1);
    }
}

.reader-selection-menu {
    position: absolute;
    z-index: 60;
    pointer-events: auto;
    transform: translate(-50%, -100%);
    transform-origin: 50% 100%;
    animation: rd-pop 180ms cubic-bezier(0.2, 0.9, 0.3, 1.1);
}

.reader-selection-menu.is-below {
    transform: translate(-50%, 12px);
    transform-origin: 50% 0%;
    animation-name: rd-pop-below;
}

.reader-selection-menu[hidden] {
    display: none !important;
}

.reader-selection-menu-panel {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.5rem 0.625rem;
    background: var(--rd-chrome-bg);
    color: var(--rd-fg);
    border: 1px solid var(--rd-hairline);
    border-radius: 14px;
    box-shadow: 0 10px 30px -8px rgba(40, 28, 12, 0.22), 0 2px 6px rgba(40, 28, 12, 0.08);
    font-family: var(--rd-ui-font);
    font-size: 0.75rem;
    white-space: nowrap;
}

.reader-selection-colors {
    display: flex;
    gap: 0.375rem;
    padding-right: 0.5rem;
    margin-right: 0.125rem;
    border-right: 1px solid var(--rd-hairline);
}

.reader-selection-color {
    width: 1.375rem;
    height: 1.375rem;
    padding: 0;
    border-radius: 999px;
    border: 1px solid rgba(40, 28, 12, 0.15);
    cursor: pointer;
    flex-shrink: 0;
    transition: transform 0.12s;
}

.reader-selection-color:hover {
    transform: scale(1.08);
}

.reader-selection-color[data-color="sun"] { background: oklch(0.92 0.10 85); }
.reader-selection-color[data-color="rose"] { background: oklch(0.86 0.09 30); }
.reader-selection-color[data-color="sage"] { background: oklch(0.88 0.06 145); }
.reader-selection-color[data-color="sky"] { background: oklch(0.88 0.06 230); }

.reader-selection-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.3125rem;
    padding: 0.375rem 0.5625rem;
    border: none;
    border-radius: 8px;
    background: transparent;
    color: var(--rd-fg);
    font-family: inherit;
    font-size: inherit;
    font-weight: 500;
    cursor: pointer;
    flex-shrink: 0;
}

.reader-selection-btn:hover {
    background: var(--rd-accent-soft);
}

.reader-selection-btn svg {
    flex-shrink: 0;
}

.reader-selection-menu-tail {
    position: absolute;
    left: 50%;
    bottom: -6px;
    transform: translateX(-50%) rotate(45deg);
    width: 10px;
    height: 10px;
    background: var(--rd-chrome-bg);
    border-right: 1px solid var(--rd-hairline);
    border-bottom: 1px solid var(--rd-hairline);
    pointer-events: none;
}

.reader-selection-menu.is-below .reader-selection-menu-tail {
    bottom: auto;
    top: -6px;
    border-right: 1px solid var(--rd-hairline);
    border-top: 1px solid var(--rd-hairline);
    border-bottom: none;
}

/* ── In-text highlights ──────────────────────────────────────────── */
.reader-content mark.reader-highlight {
    padding: 0.05em 0;
    border-radius: 0.15em;
    color: inherit;
}

.reader-highlight--sun { background: oklch(0.92 0.10 85 / 0.45); }
.reader-highlight--rose { background: oklch(0.86 0.09 30 / 0.45); }
.reader-highlight--sage { background: oklch(0.88 0.06 145 / 0.45); }
.reader-highlight--sky { background: oklch(0.88 0.06 230 / 0.45); }

/* ── Note / comment composer ─────────────────────────────────────── */
.reader-note-composer {
    position: absolute;
    inset: 0;
    z-index: 185;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding: 0 1rem max(1.5rem, env(safe-area-inset-bottom));
    pointer-events: none;
}

.reader-note-composer:not([hidden]) {
    pointer-events: auto;
}

.reader-note-composer[hidden] {
    display: none !important;
}

.reader-note-composer-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(40, 28, 12, 0.28);
    animation: rd-fade-in 0.18s ease;
}

.reader-note-composer-sheet {
    position: relative;
    z-index: 1;
    width: min(26.25rem, 100%);
    background: var(--rd-chrome-bg);
    border: 1px solid var(--rd-hairline);
    border-radius: 16px;
    box-shadow: 0 18px 40px -12px rgba(40, 28, 12, 0.22);
    padding: 0.875rem;
    font-family: var(--rd-ui-font);
    animation: rd-slide-up 220ms cubic-bezier(0.2, 0.9, 0.3, 1.1);
}

.reader-note-composer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.625rem;
}

.reader-note-composer-kicker {
    font-size: 0.66rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--rd-muted);
}

.reader-note-composer-close {
    min-width: 2rem;
    min-height: 2rem;
}

.reader-note-composer-quote {
    margin: 0 0 0.75rem;
    padding-left: 0.625rem;
    border-left: 2px solid var(--rd-accent);
    font-family: var(--rd-body-font);
    font-style: italic;
    font-size: 0.8125rem;
    line-height: 1.55;
    color: var(--rd-fg);
    max-height: 4.375rem;
    overflow: hidden;
}

.reader-note-composer-input {
    display: block;
    width: 100%;
    box-sizing: border-box;
    min-height: 4rem;
    padding: 0.625rem 0.75rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 10px;
    background: var(--rd-bg);
    color: var(--rd-fg);
    font-family: var(--rd-ui-font);
    font-size: 0.8125rem;
    line-height: 1.5;
    resize: vertical;
}

.reader-note-composer-input:focus {
    outline: 2px solid var(--rd-accent);
    outline-offset: 1px;
}

.reader-note-composer-footer {
    display: flex;
    justify-content: flex-end;
    margin-top: 0.625rem;
}

.reader-note-composer-save {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 999px;
    background: var(--rd-fg);
    color: var(--rd-bg);
    font-family: inherit;
    font-size: 0.75rem;
    font-weight: 500;
    cursor: pointer;
}

.reader-note-composer-save:hover {
    opacity: 0.88;
}

.reader-note-composer-save:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* ── Comment visibility (composer) ───────────────────────────────── */
.reader-comment-visibility {
    margin-bottom: 0.75rem;
}

.reader-comment-disclaimer {
    margin: 0 0 0.625rem;
    font-family: var(--rd-ui-font);
    font-size: 0.75rem;
    line-height: 1.45;
    color: var(--rd-muted);
}

.reader-comment-visibility-options {
    margin: 0;
    padding: 0;
    border: none;
}

.reader-comment-visibility-legend {
    font-family: var(--rd-ui-font);
    font-size: 0.66rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--rd-muted);
    margin-bottom: 0.375rem;
}

.reader-comment-visibility-option {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--rd-ui-font);
    font-size: 0.8125rem;
    color: var(--rd-fg);
    margin-bottom: 0.375rem;
    cursor: pointer;
}

/* ── Chapter comments (readers) ──────────────────────────────────── */
.reader-chapter-comments {
    margin: 0 1rem 1rem;
    padding: 0.875rem 1rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 12px;
    background: color-mix(in oklch, var(--rd-chrome-bg) 92%, var(--rd-accent));
}

.reader-chapter-comment {
    padding: 0.625rem 0;
    border-bottom: 1px solid var(--rd-hairline);
}

.reader-chapter-comment:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.reader-chapter-comment-badge {
    display: inline-block;
    margin-bottom: 0.375rem;
    font-family: var(--rd-ui-font);
    font-size: 0.625rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--rd-muted);
}

.reader-chapter-comment-quote {
    margin: 0 0 0.375rem;
    padding-left: 0.5rem;
    border-left: 2px solid var(--rd-accent);
    font-size: 0.8125rem;
    font-style: italic;
    color: var(--rd-muted);
}

.reader-chapter-comment-text {
    margin: 0;
    font-family: var(--rd-body-font);
    font-size: 0.875rem;
    line-height: 1.55;
}

.reader-chapter-comment-reply {
    margin-top: 0.5rem;
    padding: 0.5rem 0.625rem;
    border-radius: 8px;
    background: var(--rd-bg);
    font-family: var(--rd-body-font);
    font-size: 0.8125rem;
    line-height: 1.5;
}

.reader-chapter-comment-reply-label {
    display: block;
    margin-bottom: 0.25rem;
    font-family: var(--rd-ui-font);
    font-size: 0.625rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--rd-accent);
    font-weight: 600;
}

/* ── Author comments sheet ───────────────────────────────────────── */
.reader-comments-sheet {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(24rem, 100%);
    z-index: 2;
    display: flex;
    flex-direction: column;
    background: var(--rd-chrome-bg);
    border-left: 1px solid var(--rd-hairline);
    box-shadow: -8px 0 24px rgba(40, 28, 12, 0.08);
    font-family: var(--rd-ui-font);
}

.reader-comments-sheet[hidden] {
    display: none !important;
}

.reader-comments-toolbar {
    display: flex;
    align-items: flex-end;
    gap: 0.625rem;
    padding: 0 1rem 0.75rem;
    border-bottom: 1px solid var(--rd-hairline);
}

.reader-comments-filter {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    font-size: 0.66rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--rd-muted);
}

.reader-comments-select {
    width: 100%;
    padding: 0.375rem 0.5rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 8px;
    background: var(--rd-bg);
    color: var(--rd-fg);
    font-family: inherit;
    font-size: 0.8125rem;
}

.reader-comments-refresh {
    padding: 0.4375rem 0.75rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 999px;
    background: transparent;
    color: var(--rd-fg);
    font-family: inherit;
    font-size: 0.75rem;
    cursor: pointer;
}

.reader-comments-list {
    flex: 1;
    overflow-y: auto;
    padding: 0.75rem 1rem 1.5rem;
    -webkit-overflow-scrolling: touch;
}

.reader-comments-empty,
.reader-comments-loading {
    margin: 0;
    font-size: 0.8125rem;
    color: var(--rd-muted);
    text-align: center;
    padding: 2rem 0;
}

.reader-author-comment {
    padding: 0.875rem 0;
    border-bottom: 1px solid var(--rd-hairline);
}

.reader-author-comment-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem 0.625rem;
    margin-bottom: 0.5rem;
    font-size: 0.6875rem;
    color: var(--rd-muted);
}

.reader-author-comment-chapter {
    font-weight: 600;
    color: var(--rd-fg);
}

.reader-author-comment-vis {
    padding: 0.125rem 0.375rem;
    border-radius: 4px;
    background: var(--rd-bg);
}

.reader-author-comment-quote {
    margin: 0 0 0.375rem;
    padding-left: 0.5rem;
    border-left: 2px solid var(--rd-accent);
    font-family: var(--rd-body-font);
    font-size: 0.8125rem;
    font-style: italic;
}

.reader-author-comment-text {
    margin: 0 0 0.625rem;
    font-family: var(--rd-body-font);
    font-size: 0.875rem;
    line-height: 1.55;
}

.reader-author-comment-reply {
    padding: 0.5rem 0.625rem;
    border-radius: 8px;
    background: var(--rd-bg);
}

.reader-author-comment-reply-label {
    font-size: 0.625rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--rd-accent);
    margin-bottom: 0.25rem;
}

.reader-author-comment-reply-form {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.reader-author-reply-input {
    width: 100%;
    box-sizing: border-box;
    padding: 0.5rem 0.625rem;
    border: 1px solid var(--rd-hairline);
    border-radius: 8px;
    background: var(--rd-bg);
    color: var(--rd-fg);
    font-family: var(--rd-ui-font);
    font-size: 0.8125rem;
    resize: vertical;
}

.reader-author-reply-btn {
    align-self: flex-end;
    padding: 0.4375rem 0.875rem;
    border: none;
    border-radius: 999px;
    background: var(--rd-fg);
    color: var(--rd-bg);
    font-family: inherit;
    font-size: 0.75rem;
    cursor: pointer;
}

.reader-author-reply-btn:disabled {
    opacity: 0.5;
}

/* ── Action toast ────────────────────────────────────────────────── */
.reader-selection-toast {
    position: absolute;
    left: 50%;
    bottom: max(4.5rem, calc(env(safe-area-inset-bottom) + 3.5rem));
    transform: translateX(-50%) translateY(8px);
    z-index: 65;
    padding: 0.5rem 0.875rem;
    background: var(--rd-fg);
    color: var(--rd-bg);
    border-radius: 999px;
    font-family: var(--rd-ui-font);
    font-size: 0.75rem;
    font-weight: 500;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.18s ease, transform 0.18s ease;
}

.reader-selection-toast.is-visible {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

@media (max-width: 639px) {
    .reader-selection-menu-panel {
        max-width: calc(100vw - 2rem);
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
}

/* ── Glossary terms (EPUB span.u) ───────────────────────────────── */
.reader-content span.u[data-glossary-id],
.reader-content a[data-glossary-id] {
    text-decoration: underline;
    text-decoration-color: color-mix(in oklch, var(--rd-accent) 55%, transparent);
    text-underline-offset: 0.14em;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
}

.reader-content span.u[data-glossary-id]:hover,
.reader-content a[data-glossary-id]:hover {
    color: var(--rd-accent);
}

/* ── Glossary modal (matches footnote popup UX) ─────────────────── */
.reader-glossary-modal {
    position: fixed;
    inset: 0;
    z-index: 190;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: max(1rem, env(safe-area-inset-top)) max(1rem, env(safe-area-inset-right))
        max(1rem, env(safe-area-inset-bottom)) max(1rem, env(safe-area-inset-left));
    pointer-events: none;
}

.reader-glossary-modal[hidden] {
    display: none !important;
}

.reader-glossary-modal:not([hidden]) {
    pointer-events: auto;
}

.reader-glossary-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(40, 28, 12, 0.38);
    animation: rd-fade-in 0.18s ease;
}

.reader-glossary-card {
    position: relative;
    z-index: 1;
    width: min(34rem, 100%);
    max-height: min(70dvh, 28rem);
    display: flex;
    flex-direction: column;
    background: var(--rd-bg);
    color: var(--rd-fg);
    border: 1px solid var(--rd-hairline);
    border-radius: 12px;
    box-shadow: 0 18px 40px -12px rgba(40, 28, 12, 0.22);
    animation: rd-fade-in 0.2s ease;
    overflow: hidden;
}

.reader-glossary-close {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    z-index: 2;
    min-width: 2.75rem;
    min-height: 2.75rem;
    touch-action: manipulation;
}

.reader-glossary-close svg {
    pointer-events: none;
}

.reader-glossary-title {
    flex-shrink: 0;
    padding: 1rem 3rem 0.35rem 1.25rem;
    font-family: var(--rd-body-font);
    font-size: calc(1.05rem * var(--rd-font-scale, 1));
    font-weight: 600;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.reader-glossary-body {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 0 1.25rem 1.25rem;
    font-family: var(--rd-body-font);
    font-size: calc(0.95rem * var(--rd-font-scale, 1));
    line-height: 1.62;
}

.reader-glossary-body p {
    margin: 0;
    text-align: left;
}

.book-reader-body.reader-glossary-open {
    overflow: hidden;
}

.book-reader-app.reader-glossary-open .reader-content {
    overflow: hidden;
}