/* =========================================================
   Reveal.js Slide Layout
   Used by learning topic slide decks
   ========================================================= */

.reveal {
    font-family: Inter, Arial, sans-serif;
}

.reveal h1,
.reveal h2,
.reveal h3 {
    letter-spacing: -0.03em;
    line-height: 1.1;
}

.reveal h1,
.reveal h2,
.reveal h3,
.reveal p,
.reveal li {
    color: inherit;
}

.reveal section {
    text-align: left;
    padding: 2rem;
}

.reveal section > ul,
.reveal section > ol {
    margin-top: 1rem;
    /*max-width: 780px;*/
}

.reveal li {
    margin-bottom: 1rem;
}

/* =========================================================
   Slide Wrapper
   Outer frame around Reveal.js
   ========================================================= */

.slides-wrapper {
    background: linear-gradient(135deg, #0f172a, #1e293b);
    padding: 1rem;
    border-radius: 28px;

    width: 100%;
    min-height: 680px;
    box-sizing: border-box;

    box-shadow:
        0 20px 50px rgba(15, 23, 42, 0.25),
        inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.slides-wrapper .reveal {
    width: 100%;
    height: 650px !important;

    background: #eef2f7; /*#ffffff;*/
    border-radius: 20px;
    overflow: hidden;

    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.12);
}

.slides-wrapper .reveal .slides {
    width: 100%;
    height: 100%;
}

/* Fullscreen version */
.slides-wrapper .reveal:fullscreen {
    width: 100vw !important;
    height: 100vh !important;
    border-radius: 0;
}

/* =========================================================
   Light / Dark Slide Themes
   ========================================================= */

.slides-wrapper .reveal.slide-light {
    background:
        linear-gradient(rgba(238, 242, 247, 0.55), rgba(238, 242, 247, 0.55)),
        url("../images/slide-bg-light.png");

    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;

    color: #0f172a;

}

.slides-wrapper .reveal.slide-dark {
    background: #0f172a;
    color: #e5e7eb;
}

.reveal.slide-light {
    color: #5b5fa8;
}

.reveal.slide-light h1,
.reveal.slide-light h2,
.reveal.slide-light h3,
.reveal.slide-light p,
.reveal.slide-light li {
    color: #5b5fa8;
}

.reveal .stress-word {
    color: #e6004f;
    font-weight: 800;
}

.reveal.slide-dark h1,
.reveal.slide-dark h2,
.reveal.slide-dark h3,
.reveal.slide-dark p,
.reveal.slide-dark li,
.reveal.slide-dark td,
.reveal.slide-dark th {
    color: #e5e7eb;
}

/* Optional slide-level dark style */
.reveal section.dark-slide h1,
.reveal section.dark-slide h2,
.reveal section.dark-slide h3,
.reveal section.dark-slide p,
.reveal section.dark-slide li {
    color: #e5e7eb;
}

/* =========================================================
   Slide Index / Menu
   Used on first slide to jump to lesson sections
   ========================================================= */

.reveal .slide-subtitle {
    margin-top: -0.5rem;
    color: #64748b;
    font-size: 1.2rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.reveal .slide-note {
    margin-top: 1.5rem;
    color: #64748b;
    font-size: 1rem;
}

/* =========================================================
   Scrollable Lesson Menu
   ========================================================= */

.reveal .slide-menu {
    display: grid !important;
    grid-template-columns: 1fr !important;
    gap: 1.25rem !important;

    width: min(980px, 88%);
    margin: 1.5rem auto 1.2rem;

    /* Keep long menus inside the slide */
    max-height: 410px;
    overflow-y: auto;
    overflow-x: hidden;

    /* Space between menu items and scrollbar */
    padding: 0.25rem 0.7rem 0.25rem 0.25rem;
    box-sizing: border-box;

    /* Prevent layout jumping when scrollbar appears */
    scrollbar-gutter: stable;

    /* Better touch scrolling on tablets */
    -webkit-overflow-scrolling: touch;

    /* Keep scrolling inside the menu */
    overscroll-behavior: contain;
}

.reveal .slide-menu a {
    display: flex !important;
    align-items: center;

    width: 100%;
    min-height: 76px;
    box-sizing: border-box;

    padding: 1.25rem 1.6rem;
    border-radius: 22px;

    background: #f8fafc;
    border: 1px solid #e2e8f0;

    color: #0f172a !important;
    text-decoration: none !important;

    font-size: 1.28rem;
    font-weight: 700;
    line-height: 1.35;

    box-shadow: 0 10px 28px rgba(15, 23, 42, 0.08);
    transition: all 0.2s ease;
}

.reveal .slide-menu a:hover {
    transform: translateY(-3px);
    background: #0f172a;
    color: white !important;
    border-color: #0f172a;
    box-shadow: 0 18px 40px rgba(15, 23, 42, 0.2);
}

/* Chrome / Edge / Safari */
.reveal .slide-menu::-webkit-scrollbar {
    width: 10px;
}

.reveal .slide-menu::-webkit-scrollbar-track {
    background: #e2e8f0;
    border-radius: 999px;
}

.reveal .slide-menu::-webkit-scrollbar-thumb {
    background: #94a3b8;
    border-radius: 999px;
}

.reveal .slide-menu::-webkit-scrollbar-thumb:hover {
    background: #64748b;
}

/* Firefox */
.reveal .slide-menu {
    scrollbar-width: thin;
    scrollbar-color: #94a3b8 #e2e8f0;
}

/* =========================================================
   Scrollable Frame
   ========================================================= */
.reveal .slide-scroll-frame {
    max-height: 470px;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 0.4rem 0.9rem 0.4rem 0.2rem;
    box-sizing: border-box;
    scrollbar-gutter: stable;
}

/* =========================================================
   Pedagogical Slide Elements
   ========================================================= */

.reveal .slide-objective-box {
    max-width: 1050px;

    border-radius: 24px;
    background: #eff6ff;
    border: 2px solid #bfdbfe;

    color: #1e3a8a;
    font-weight: 700;

    margin: 1.1rem auto 1.3rem;
    padding: 1.2rem 1.5rem;
    font-size: 1.2rem;
    line-height: 1.32;

    box-shadow: 0 12px 32px rgba(37, 99, 235, 0.08);
}

.reveal .slide-objective-box ul {
    margin: 0;
    padding-left: 1.4rem;
}

.reveal .slide-objective-box li {
    font-size: 1.65rem;
    line-height: 1.4;
    font-weight: 800;

    margin-bottom: 1rem;
    padding: 0.7rem 1rem;

    border-radius: 18px;

    background: rgba(91, 95, 168, 0.10);
    color: #34387f;
}

.reveal .slide-objective-box li:last-child {
    margin-bottom: 0;
}

.reveal .slide-objective-box li::marker {
    color: #e6004f;
    font-size: 1.5em;
}

.reveal .warning-box,
.reveal .exam-tip-box,
.reveal .key-term-box {
    max-width: 1050px;
    margin: 1.6rem auto;
    padding: 1.35rem 1.7rem;

    border-radius: 24px;
    font-size: 1.32rem;
    line-height: 1.5;
    text-align: left;

    box-shadow: 0 12px 30px rgba(15, 23, 42, 0.08);
}

/* Common mistake / warning */
.reveal .warning-box {
    background: #fff7ed;
    border: 1px solid #fed7aa;
    color: #7c2d12;
}

/* Exam tip / useful advice */
.reveal .exam-tip-box {
    background: rgba(91, 95, 168, 0.10);
    border: 1px solid rgba(91, 95, 168, 0.28);
    color: #4b4f9c;
}

/* Key term / definition */
.reveal .key-term-box {
    background: #f8fafc;
    border: 1px solid #cbd5e1;
    color: #334155;
}

/* Dark mode versions */
.reveal.slide-dark .slide-objective-box {
    background: #172554;
    border-color: #1d4ed8;
    color: #dbeafe;
}

.reveal.slide-dark .warning-box {
    background: #431407;
    border-color: #9a3412;
    color: #fed7aa;
}

.reveal.slide-dark .exam-tip-box {
    background: #052e16;
    border-color: #15803d;
    color: #bbf7d0;
}

.reveal.slide-dark .key-term-box {
    background: #1e293b;
    border-color: #475569;
    color: #e2e8f0;
}

/* =========================================================
   Numbers, Digits, and Equations
   ========================================================= */

.reveal .big-number {
    display: inline-block;

    margin: 1rem 0;
    padding: 0.65rem 1.45rem;

    border-radius: 20px;
    background: #f8fafc;
    border: 2px solid #e2e8f0;

    color: #0f172a;
    font-size: 3rem;
    font-weight: 850;
    letter-spacing: 0.05em;

    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.06);
}

.reveal .digit-row {
    margin: 1.3rem auto;
    padding: 1.15rem 1.7rem;

    max-width: fit-content;

    border-radius: 24px;
    background: #f8fafc;
    border: 2px solid #e2e8f0;

    color: #0f172a;
    font-size: 1.9rem;
    font-weight: 800;
    letter-spacing: 0.18em;

    box-shadow: 0 10px 26px rgba(15, 23, 42, 0.07);
}

.reveal .keywords-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: 0.8rem;
}

.reveal .keywords-title {
    font-size: 1.4rem;
    white-space: nowrap;
}

.reveal .keyword-line {
    display: inline-block;
    margin: 0;

    padding: 0.65rem 1rem;
    border-radius: 18px;

    background: #f8fafc;
    border: 1px solid #e2e8f0;

    color: #334155;
    font-size: 1.15rem;
    font-weight: 700;
    line-height: 1.4;
}
.reveal .slide-equation {
    margin: 1.4rem auto;
    padding: 1rem 1.45rem;

    max-width: fit-content;

    border-radius: 20px;
    background: #f8fafc;
    border: 2px solid #cbd5e1;

    color: #0f172a;
    font-size: 1.55rem;
    font-weight: 800;

    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.07);
}
/* Dark mode versions */
.reveal.slide-dark .big-number,
.reveal.slide-dark .digit-row,
.reveal.slide-dark .slide-equation {
    background: #1e293b;
    border-color: #475569;
    color: #f8fafc;
}

.reveal.slide-dark .keyword-line {
    color: #cbd5e1;
}

/* =========================================================
   Slide Tables
   ========================================================= */

.reveal .slide-table {
    width: 100%;
    max-width: 1100px;
    margin: 1.6rem auto;

    border-collapse: separate;
    border-spacing: 0;
    overflow: hidden;

    border-radius: 22px;
    box-shadow: 0 14px 36px rgba(15, 23, 42, 0.10);

    font-size: 1.25rem;
}

.reveal .slide-table th,
.reveal .slide-table td {
    padding: 1rem 1.25rem;
    text-align: center;
    border: 1px solid #e2e8f0;
}

.reveal .slide-table th {
    background: #f1f5f9;
    color: #334155;
    font-weight: 800;
}

.reveal .slide-table td {
    background: white;
    color: #0f172a;
    font-weight: 700;
}

.reveal .slide-table td:first-child,
.reveal .slide-table th:first-child {
    text-align: left;
    background: #f8fafc;
    color: #334155;
    font-weight: 800;
}

/* Rounded table corners */
.reveal .slide-table tr:first-child th:first-child,
.reveal .slide-table tr:first-child td:first-child {
    border-top-left-radius: 22px;
}

.reveal .slide-table tr:first-child th:last-child,
.reveal .slide-table tr:first-child td:last-child {
    border-top-right-radius: 22px;
}

.reveal .slide-table tr:last-child th:first-child,
.reveal .slide-table tr:last-child td:first-child {
    border-bottom-left-radius: 22px;
}

.reveal .slide-table tr:last-child th:last-child,
.reveal .slide-table tr:last-child td:last-child {
    border-bottom-right-radius: 22px;
}

/* Dark mode table */
.reveal.slide-dark .slide-table {
    box-shadow: 0 14px 36px rgba(0, 0, 0, 0.35);
}

.reveal.slide-dark .slide-table th {
    background: #334155;
    border-color: #475569;
    color: #e5e7eb;
}

.reveal.slide-dark .slide-table td {
    background: #1e293b;
    border-color: #475569;
    color: #e5e7eb;
}

.reveal.slide-dark .slide-table td:first-child,
.reveal.slide-dark .slide-table th:first-child {
    background: #0f172a;
    color: #e5e7eb;
}

/* =========================================================
   Responsive Adjustments
   ========================================================= */

@media (max-width: 768px) {
    .slides-wrapper {
        min-height: 560px;
        padding: 0.65rem;
        border-radius: 22px;
    }

    .slides-wrapper .reveal {
        height: 540px !important;
        border-radius: 16px;
    }

    .reveal section {
        padding: 1.25rem;
    }

    .reveal .big-number {
        font-size: 2rem;
    }

    .reveal .digit-row {
        font-size: 1.15rem;
        letter-spacing: 0.04em;
    }

    .reveal .slide-objective-box {
        font-size: 1.05rem;
    }

    .reveal .slide-table {
        font-size: 0.75rem;
    }

    .reveal .slide-table th,
    .reveal .slide-table td {
        padding: 0.45rem 0.5rem;
    }

    .reveal .slide-menu {
        width: 94%;
        max-height: 320px;
        gap: 0.75rem !important;
        margin-top: 1rem;
    }

    .reveal .slide-menu a {
        min-height: 58px;
        padding: 0.8rem 1rem;
        font-size: 1rem;
    }
}

/* =========================================================
   Small corner images for slides
   ========================================================= */

.reveal section {
    position: relative;
}

.reveal .slide-corner-image {
    position: absolute;
    top: 2rem;
    right: 2rem;

    width: 260px;
    max-width: 28%;
    height: auto;

    border-radius: 22px;
    object-fit: cover;

    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.18);
}

.reveal .slide-corner-image.small {
    width: 210px;
}

.reveal .slide-corner-image.medium {
    width: 280px;
}

.reveal .slide-corner-image.large {
    width: 340px;
}

.reveal .slide-with-corner-image {
    padding-right: 22rem;
}

/* =========================================================
   Two-column slide layout
   ========================================================= */

.reveal .slide-two-column {
    display: grid;
    grid-template-columns: 1.25fr 0.75fr;
    gap: 2rem;
    align-items: start;
}

.reveal .compact-binary-slide p {
    margin-top: 0.7rem;
    margin-bottom: 0.7rem;
}

.reveal .compact-binary-slide .slide-image-group {
    margin-top: 0.0rem;
    margin-bottom: 2rem;
}

.reveal .compact-binary-slide .slide-image {
    margin-bottom: 0.0rem;
}

.reveal .binary-visual-side {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.2rem;
}

.reveal .binary-visual-side .slide-image {
    width: 100%;
    max-width: 360px;
    max-height: 220px;
    object-fit: cover;
    border-radius: 22px;
    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.18);
}

.reveal .binary-state-card {
    width: 100%;
    max-width: 360px;

    display: grid;
    gap: 0.65rem;

    padding: 1rem 1.2rem;
    border-radius: 22px;

    background: #f8fafc;
    border: 2px solid #e2e8f0;

    color: #0f172a;
    font-size: 1.35rem;
    font-weight: 700;
    line-height: 1.3;

    box-shadow: 0 10px 26px rgba(15, 23, 42, 0.08);
}

.reveal.slide-dark .binary-state-card {
    background: #1e293b;
    border-color: #475569;
    color: #e5e7eb;
}

/* Image attribution under slide images */
.reveal .slide-image-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}

.reveal .image-caption {
    margin: 0;
    font-size: 0.72rem;
    color: #64748b;
    text-align: center;
    line-height: 1.2;
}

/* =========================================================
   Large image in the center
   ========================================================= */
.reveal .single-image-slide {
    min-height: 460px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.reveal .slide-main-image {
    width: min(820px, 88%);
    max-height: 430px;
    object-fit: contain;
    border-radius: 24px;
    box-shadow: 0 16px 38px rgba(15, 23, 42, 0.18);
}
.reveal .slide-image-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}
.reveal .image-caption {
    margin: 0;
    font-size: 0.72rem;
    color: #64748b;
    text-align: center;
    line-height: 1.2;
}

/* =========================================================
   Embedded image zoom for Reveal.js
   Works inside normal slides and fullscreen slides
   ========================================================= */

.reveal .zoomable-slide-image,
.reveal .zoomable-slide-image img {
    cursor: zoom-in;
}

.reveal .slide-image-lightbox {
    position: absolute;
    inset: 0;
    z-index: 99999;

    display: none;
    align-items: center;
    justify-content: center;

    background: rgba(15, 23, 42, 0.9);
    padding: 2rem;
}

.reveal .slide-image-lightbox.active {
    display: flex;
}

.reveal .slide-image-lightbox img {
    max-width: 92%;
    max-height: 88%;
    object-fit: contain;

    border-radius: 24px;
    background: white;
    box-shadow: 0 24px 70px rgba(0, 0, 0, 0.45);
}

.reveal .slide-image-lightbox-close {
    position: absolute;
    top: 1.2rem;
    right: 1.2rem;

    width: 44px;
    height: 44px;

    border: none;
    border-radius: 999px;

    background: white;
    color: #0f172a;

    font-size: 1.8rem;
    cursor: pointer;
}

.reveal .slide-image-lightbox img.pixelated-image {
    image-rendering: pixelated;
    image-rendering: crisp-edges;
}

/* =========================================================
   Zoomable table for Reveal.js slides
   ========================================================= */

.reveal .zoomable-table-wrapper {
    width: min(1050px, 94%);
    max-width: none;
    margin: 0.8rem auto;
    cursor: zoom-in;
}

.reveal .zoomable-table-wrapper .slide-table {
    width: 100%;
    max-width: none;
}

.reveal .zoom-hint {
    margin: 0 0 0.4rem;
    text-align: center;
    font-size: 0.85rem;
    color: #64748b;
    font-weight: 700;
}

.reveal .compact-table {
    font-size: 0.9rem;
    margin: 0 auto;
}

.reveal .compact-table th,
.reveal .compact-table td {
    padding: 0.35rem 0.55rem;
}

.reveal .table-lightbox {
    position: fixed;
    inset: 0;
    z-index: 999999;

    display: none;
    align-items: center;
    justify-content: center;

    background: rgba(15, 23, 42, 0.92);
    padding: 2rem;
}

.reveal .table-lightbox.active {
    display: flex;
}

.reveal .table-lightbox-content {
    background: white;
    color: #0f172a;
    padding: 2rem;
    border-radius: 28px;
    max-width: 92vw;
    max-height: 88vh;
    overflow: auto;
    box-shadow: 0 24px 70px rgba(0, 0, 0, 0.45);
    cursor: zoom-out;
}

.reveal .table-lightbox-content table {
    font-size: 1.45rem;
    min-width: 520px;
}

.reveal .table-lightbox-content th,
.reveal .table-lightbox-content td {
    padding: 0.8rem 1.4rem;
}

/* ===== Reveal PDF / Print Mode Fix ===== */

@media print {
    body {
        margin: 0 !important;
        background: white !important;
    }

    header,
    nav,
    footer,
    .navbar,
    .topic-top-nav,
    .learning-label,
    .topic-page h1,
    .slides-controls,
    #studyMode,
    #allDecks {
        display: none !important;
    }

    .topic-page,
    .learning-shell,
    #slidesMode,
    .slides-wrapper {
        width: 100% !important;
        max-width: none !important;
        margin: 0 !important;
        padding: 0 !important;
        background: white !important;
        box-shadow: none !important;
        border-radius: 0 !important;
    }

    .slides-wrapper .reveal {
        width: 100vw !important;
        height: 100vh !important;
        border-radius: 0 !important;
        box-shadow: none !important;
        overflow: visible !important;
    }

    .reveal .slide-menu {
        max-height: none !important;
        overflow: visible !important;
    }

    .topic-side-toc,
    .show-topic-toc-btn,
    .back-to-top-btn {
        display: none !important;
    }

    .topic-reading-main {
        width: 100% !important;
        max-width: none !important;
        margin: 0 !important;
    }

    .reveal .slide-menu,
    .reveal .slide-scroll-frame {
        max-height: none !important;
        height: auto !important;
        overflow: visible !important;
        scrollbar-gutter: auto !important;
    }
}

@page {
    size: landscape;
    margin: 0;
}

.reveal .slide-number {
    left: 24px !important;
    right: auto !important;
    bottom: 18px !important;

    width: auto !important;
    min-width: 0 !important;

    display: inline-flex !important;
    align-items: center;
    justify-content: center;

    padding: 0.25rem 0.65rem;
    border-radius: 999px;

    background: rgba(255, 255, 255, 0.75);
    color: #5b5fa8;

    font-size: 0.9rem;
    font-weight: 700;

    cursor: pointer;
}

/* =========================================================
   BCD Title Slide
   ========================================================= */

.reveal .title-slide {
    display: flex;
    align-items: center;
    justify-content: center;

    text-align: center;
    height: 100%;

    background:
        radial-gradient(circle at top left,
            rgba(91, 95, 168, 0.10),
            transparent 35%),
        radial-gradient(circle at bottom right,
            rgba(230, 0, 79, 0.08),
            transparent 35%);
}

.reveal .title-content {
    max-width: 900px;
}

.reveal .topic-label {
    display: inline-block;

    padding: 0.45rem 1rem;
    margin-bottom: 1.8rem;

    border-radius: 999px;

    background: rgba(91, 95, 168, 0.10);
    border: 1px solid rgba(91, 95, 168, 0.22);

    color: #5b5fa8;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.reveal .title-slide h1 {
    margin: 0;

    font-size: clamp(4rem, 8vw, 6.5rem);
    font-weight: 900;
    line-height: 0.95;
    letter-spacing: -0.05em;

    color: #0f172a;
}

.reveal .title-slide h3 {
    margin-top: 1rem;
    margin-bottom: 1.8rem;

    font-size: 2rem;
    font-weight: 700;

    color: #5b5fa8;
}

.reveal .title-line {
    width: 180px;
    height: 6px;

    margin: 0 auto 1.6rem;

    border-radius: 999px;

    background: linear-gradient(
        90deg,
        #5b5fa8,
        #e6004f
    );
}

.reveal .title-subtitle {
    font-size: 1.35rem;
    font-weight: 600;
    color: #475569;
}

/* =========================================================
   EXIT TICKET - QR Code
   ========================================================= */

/* Reusable Exit Ticket Container */
.exit-ticket-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 50px;
    margin-top: 30px;
}

/* Text and Link Wrapper */
.exit-ticket-info {
    text-align: left;
}

.exit-ticket-link {
    font-size: 0.8em;
    color: #3498db;
}

/* Large, Scannable QR Code Styling */
.exit-ticket-qr {
    width: 400px;
    height: 400px;
    border: 5px solid #fff;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

/* =========================================================
   Reveal.js Optional Branch / Fork Slides
   ========================================================= */

.reveal .branch-choice-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

.reveal .branch-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;

    padding: 0.65rem 1.1rem;
    border-radius: 999px;

    background: #5b5fa8;
    color: white !important;

    font-size: 1rem;
    font-weight: 800;
    text-decoration: none !important;

    box-shadow: 0 10px 24px rgba(91, 95, 168, 0.18);
    transition: all 0.2s ease;
}

.reveal .branch-button:hover {
    transform: translateY(-2px);
    background: #4b4f9c;
}

.reveal .branch-button.secondary {
    background: #0f172a;
}

.reveal .branch-button.secondary:hover {
    background: #1e293b;
}

.reveal .branch-instruction-box {
    margin: 1.4rem auto;
    padding: 1.2rem 1.5rem;

    border-radius: 22px;
    background: rgba(91, 95, 168, 0.10);
    border: 1px solid rgba(91, 95, 168, 0.28);

    color: #4b4f9c;
    font-size: 1.25rem;
    font-weight: 700;
    line-height: 1.5;
}

.reveal .recall-answer {
    display: inline-block;
    margin-top: 0.15rem;
    font-size: 0.68em;
    line-height: 1.25;
    color: #64748b;
    font-weight: 700;
}

.reveal .recall-answer strong {
    font-size: 0.9em;
}


/* =========================================================
   Reveal.js A-B-C-D answer options
   ========================================================= */
.reveal ol.answer-options {
    list-style-type: upper-alpha !important;
}

/* =========================================================
   Large image demonstration
   Same display area for normal and pixel-zoom images
   ========================================================= */

.reveal .image-demo-frame {
    width: min(1000px, 92%);
    height: 440px;

    margin: 0.8rem auto;

    display: flex;
    align-items: center;
    justify-content: center;

    overflow: hidden;
}

.reveal .image-demo-frame img {
    width: 100%;
    height: 100%;

    object-fit: contain;

    border-radius: 18px;
}

/* Use nearest-neighbour scaling for pixel demonstrations */
.reveal .pixelated-image {
    image-rendering: pixelated;
    image-rendering: crisp-edges;
}

.reveal .image-demo-frame.compact {
    height: 270px;
    margin: 0.2rem auto 0.4rem;
}