/* ============================================================
   BNU AI Presentation — Premium Design System
   ============================================================ */

/* —— Google Fonts —— */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

/* —— Design Tokens —— */
:root {
    color-scheme: dark;
    --primary: #00e5ff;
    --primary-glow: rgba(0, 229, 255, 0.25);
    --accent: #e040fb;
    --accent-glow: rgba(224, 64, 251, 0.2);
    --bg-deep: #07080c;
    --bg-card: rgba(255, 255, 255, 0.03);
    --text-primary: #f0f0f5;
    --text-secondary: rgba(255, 255, 255, 0.55);
    --text-dim: rgba(255, 255, 255, 0.35);
    --border-subtle: rgba(255, 255, 255, 0.08);
    --border-glow: rgba(0, 229, 255, 0.2);
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    /* Layout Standard V1.2 (Wide Canvas) */
    --safe-x: clamp(24px, 2vw, 52px);
    --safe-y: clamp(24px, 3vh, 52px);
    --content-max-single: 1480px;
    --content-max-two-col: 1600px;
    --content-max-table: 1680px;
    --title-anchor-up-step: 10px;
    /* Vertical Rhythm V1 */
    --space-title-bottom: 16px;
    --space-subtitle-bottom: 14px;
    --space-block-gap: 18px;
    --space-list-item: 6px;
    --leading-body: 1.45;
    --leading-list: 1.4;
    --ease-standard: cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: color 0.25s var(--ease-standard),
        background-color 0.25s var(--ease-standard),
        border-color 0.25s var(--ease-standard),
        box-shadow 0.3s var(--ease-standard),
        transform 0.3s var(--ease-standard),
        opacity 0.25s var(--ease-standard);
}

/* —— Reveal.js Global Overrides —— */
.reveal {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: 24px;
    color: var(--text-primary);
    letter-spacing: -0.01em;
    text-rendering: optimizeLegibility;
}

.reveal .slides>section {
    padding: var(--safe-y) var(--safe-x);
    box-sizing: border-box;
}

/* —— Typography —— */
.reveal h1 {
    font-size: 2.8em;
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.15;
    background: linear-gradient(135deg, var(--primary) 0%, #a78bfa 50%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-transform: none;
    margin-bottom: 20px;
    text-wrap: balance;
}

.reveal h2 {
    font-size: 2em;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
    color: var(--primary);
    text-transform: none;
    margin-bottom: var(--space-title-bottom);
    text-shadow: 0 0 40px var(--primary-glow);
    text-wrap: balance;
}

.reveal h3 {
    font-size: 1.45em;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.3;
    color: var(--primary);
    text-transform: none;
    margin-bottom: var(--space-title-bottom);
    text-shadow: 0 0 30px var(--primary-glow);
    text-wrap: balance;
}

.reveal p {
    font-weight: 400;
    line-height: var(--leading-body);
    color: var(--text-primary);
    margin: 0;
}

.reveal li {
    font-weight: 400;
    line-height: var(--leading-list);
    color: var(--text-primary);
}

.reveal p+p {
    margin-top: var(--space-block-gap);
}

.reveal ul,
.reveal ol {
    margin: 0;
    padding-left: 1.25em;
}

.reveal ul li,
.reveal ol li {
    margin-bottom: var(--space-list-item);
}

.reveal ul li:last-child,
.reveal ol li:last-child {
    margin-bottom: 0;
}

.reveal small,
.reveal .dim {
    color: var(--text-dim);
    font-size: 0.85em;
}

/* —— Accent Styles —— */
.reveal .highlight {
    color: var(--accent);
    font-weight: 600;
}

.reveal .subtitle {
    font-size: 1.15em;
    color: var(--text-secondary);
    font-weight: 300;
    letter-spacing: 0.01em;
    margin-bottom: var(--space-subtitle-bottom);
}

/* —— Slide Layout —— */
.slide-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: clamp(18px, 2vw, 32px);
    width: 100%;
}

/* —— Title Anchor Baseline (No Downward Drift) —— */
/* Keep the first heading on each slide at a stable default Y position.
   For dense slides, only allow upward adjustments via helper classes. */
.reveal .slides section>:is(h1, h2, h3):first-child {
    margin-top: 0;
}

.reveal .slides section.title-shift-up>:is(h1, h2, h3):first-child {
    margin-top: calc(-1 * var(--title-anchor-up-step)) !important;
}

.reveal .slides section.title-shift-up-strong>:is(h1, h2, h3):first-child {
    margin-top: calc(-2 * var(--title-anchor-up-step)) !important;
}

/* Vertical baseline for all real slides (exclude reveal stack containers). */
.reveal .slides section:not(.stack) {
    display: flex !important;
    flex-direction: column !important;
    height: 100% !important;
    min-height: 100% !important;
}

.reveal .slides section:not(.stack)>:first-child {
    margin-top: auto !important;
}

.reveal .slides section:not(.stack)>:last-child {
    margin-bottom: auto !important;
}

/* Top-title slides: pin title to anchor, center the content block below it. */
.reveal .slides section:not(.stack)>:is(h1, h2, h3):first-child {
    margin-top: 0 !important;
}

.reveal .slides section:not(.stack)>:is(h1, h2, h3):first-child+* {
    margin-top: auto !important;
}

/* Exception: end/quote/transition slides should be centered as a whole block. */
.reveal .slides section.full-center-slide>:is(h1, h2, h3):first-child {
    margin-top: auto !important;
}

/* —— Standard Layout Helpers (V1) —— */
.layout-single {
    width: min(100%, var(--content-max-single));
    margin: 0 auto;
}

.layout-two-col {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.layout-table {
    width: min(100%, var(--content-max-table));
    margin: 0 auto;
}

.stack>*+* {
    margin-top: var(--space-block-gap);
}

.text-block {
    flex: 1.15;
    text-align: left;
}

.img-block {
    flex: 0.85;
    display: flex;
    justify-content: center;
    align-items: center;
}

.img-block img,
.img-block video {
    max-width: 100%;
    max-height: 480px;
    border-radius: var(--radius-md);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
    border: 1px solid var(--border-glow);
    object-fit: contain;
    transition: var(--transition-base);
}

.img-block img:hover,
.img-block video:hover {
    transform: scale(1.02);
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.5),
        0 0 80px var(--primary-glow);
}

/* —— Speaker Profile Slide (Intro) —— */
.reveal .slides section.page-speaker-profile .slide-content {
    align-items: flex-start;
    gap: 36px;
}

.reveal .slides section.page-speaker-profile .text-block {
    flex: 1.2;
    font-size: 0.8em;
}

.reveal .slides section.page-speaker-profile .speaker-intro {
    margin-bottom: 8px !important;
    line-height: 1.3;
    font-size: 1.02em;
}

.reveal .slides section.page-speaker-profile .speaker-resume-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page-speaker-profile .speaker-resume-list li {
    margin-bottom: 0.2em;
    line-height: 1.34;
}

.reveal .slides section.page-speaker-profile .speaker-tags {
    margin-top: 10px;
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.reveal .slides section.page-speaker-profile .speaker-tags span {
    display: inline-flex;
    align-items: center;
    padding: 5px 12px;
    border-radius: 999px;
    border: 1px solid rgba(0, 229, 255, 0.35);
    background: rgba(0, 229, 255, 0.1);
    color: var(--primary);
    font-size: 0.72em;
    font-weight: 600;
    letter-spacing: 0.01em;
}

.reveal .slides section.page-speaker-profile .img-block {
    flex: 0.8;
    align-items: flex-start;
}

.reveal .slides section.page-speaker-profile .speaker-profile-panel {
    width: min(100%, 420px);
    padding: 12px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-glow);
    background: rgba(255, 255, 255, 0.04);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
}

.reveal .slides section.page-speaker-profile .speaker-avatar img {
    width: 100%;
    max-height: 250px;
    object-fit: cover;
    border-radius: 12px;
}

.reveal .slides section.page-speaker-profile .speaker-books {
    margin-top: 10px;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.reveal .slides section.page-speaker-profile .speaker-books img {
    width: 100%;
    max-height: 170px;
    object-fit: cover;
    border-radius: 10px;
}

/* —— Chapter 0 Standardization (V1) —— */
.reveal .chapter0-slides section>h2,
.reveal .chapter0-slides section>h3,
.reveal .chapter0-slides section>.subtitle {
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter0-slides section .slide-content {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.reveal .chapter0-slides section ul li,
.reveal .chapter0-slides section ol li {
    margin-bottom: var(--space-list-item);
    line-height: var(--leading-list);
}

.reveal .chapter0-slides .cover-dimline {
    margin-top: calc(var(--space-block-gap) + 8px);
}

.reveal .chapter0-slides .lead-paragraph {
    margin-bottom: var(--space-subtitle-bottom) !important;
}

.reveal .chapter0-slides .insight-card {
    margin-top: var(--space-subtitle-bottom);
    padding: 14px 16px;
}

.reveal .chapter0-slides .insight-note {
    font-size: 0.85em;
    line-height: var(--leading-body);
}

.reveal .chapter0-slides .clickable-poster {
    cursor: pointer;
}

.reveal .chapter0-slides .page3-video-player {
    display: none;
}

.reveal .chapter0-slides .video-flag {
    display: inline-flex;
    align-items: center;
    margin-left: 10px;
    padding: 3px 10px;
    border-radius: 999px;
    border: 1px solid rgba(0, 229, 255, 0.34);
    background: rgba(0, 229, 255, 0.12);
    color: var(--primary);
    font-size: 0.48em;
    font-weight: 700;
    letter-spacing: 0.01em;
    vertical-align: middle;
    transform: translateY(-1px);
    white-space: nowrap;
}

.reveal .chapter0-slides .page3-quote {
    font-size: 1.18em;
    line-height: 1.4;
    margin-bottom: var(--space-block-gap) !important;
}

.reveal .chapter0-slides section.page6-transition {
    text-align: center;
}

.reveal .chapter0-slides .transition-title {
    font-size: 1.6em;
    line-height: 1.5;
    margin-bottom: var(--space-block-gap);
}

.reveal .chapter0-slides .transition-subline {
    margin-top: calc(var(--space-block-gap) + 8px) !important;
    color: var(--accent);
    font-size: 1.18em;
    font-weight: 600;
}

.reveal .chapter0-slides .evolution-conclusion {
    margin-top: var(--space-block-gap) !important;
    font-weight: 600;
}

.reveal .chapter0-slides .bmad-dim {
    margin-top: var(--space-subtitle-bottom) !important;
}

.reveal .chapter0-slides section.page-human-hiring h3,
.reveal .chapter0-slides section.page-agent-core h3,
.reveal .chapter0-slides section.page-stanford-town h3 {
    margin-bottom: var(--space-title-bottom);
}

.reveal .chapter0-slides section.page-human-hiring .text-block p,
.reveal .chapter0-slides section.page-stanford-town .stanford-keyline {
    margin-bottom: var(--space-subtitle-bottom) !important;
}

/* —— Page 2 Carousel —— */
.page2-carousel {
    position: relative;
    width: min(100%, 640px);
    height: 480px;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-glow);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
    background: rgba(7, 8, 12, 0.55);
}

.page2-carousel-item {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 0;
    border: none !important;
    border-radius: 0 !important;
    box-shadow: none !important;
    transition: opacity 0.45s var(--ease-standard);
}

.page2-carousel-item.is-active {
    opacity: 1;
}

.page2-carousel .page2-carousel-item:hover {
    transform: none;
    box-shadow: none !important;
}

.page2-carousel-dots {
    position: absolute;
    left: 50%;
    bottom: 12px;
    transform: translateX(-50%);
    display: flex;
    gap: 8px;
    z-index: 2;
}

.page2-carousel-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.35);
    border: 1px solid rgba(255, 255, 255, 0.6);
    transition: var(--transition-base);
}

.page2-carousel-dot.is-active {
    background: var(--primary);
    border-color: var(--primary);
    box-shadow: 0 0 10px var(--primary-glow);
}

/* —— Page 8 Carousel —— */
.page8-carousel {
    position: relative;
    width: min(100%, 640px);
    height: 480px;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-glow);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
    background: rgba(7, 8, 12, 0.55);
}

.page8-carousel-item {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 0;
    border: none !important;
    border-radius: 0 !important;
    box-shadow: none !important;
    transition: opacity 0.45s var(--ease-standard);
}

.page8-carousel-item.is-active {
    opacity: 1;
}

.page8-carousel .page8-carousel-item:hover {
    transform: none;
    box-shadow: none !important;
}

.page8-carousel-dots {
    position: absolute;
    left: 50%;
    bottom: 12px;
    transform: translateX(-50%);
    display: flex;
    gap: 8px;
    z-index: 2;
}

.page8-carousel-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.35);
    border: 1px solid rgba(255, 255, 255, 0.6);
    transition: var(--transition-base);
}

.page8-carousel-dot.is-active {
    background: var(--primary);
    border-color: var(--primary);
    box-shadow: 0 0 10px var(--primary-glow);
}

/* —— Human Hiring Compact Slide —— */
.reveal .slides section.page-human-hiring h3 {
    /* Keep same visual hierarchy as other chapter titles; only shrink slightly on narrow screens */
    font-size: clamp(1.28em, 2.2vw, 1.45em);
    margin-bottom: var(--space-title-bottom);
}

.reveal .slides section.page-human-hiring .slide-content {
    align-items: flex-start;
    gap: 28px;
}

.reveal .slides section.page-human-hiring .text-block {
    flex: 1.4;
    /* Default body size aligned with chapter baseline, with mild responsive downscale */
    font-size: clamp(0.8em, 1.15vw, 0.88em);
}

.reveal .slides section.page-human-hiring .text-block p {
    line-height: var(--leading-body);
    margin-bottom: var(--space-subtitle-bottom) !important;
}

.reveal .slides section.page-human-hiring .text-block ul {
    padding-left: 1.3em;
}

.reveal .slides section.page-human-hiring .text-block ul li {
    margin-bottom: var(--space-list-item);
    line-height: var(--leading-list);
}

.reveal .slides section.page-human-hiring .img-block {
    flex: 0.7;
    align-items: flex-start;
}

.reveal .slides section.page-human-hiring .img-block img {
    max-height: 300px;
}

/* —— Agent Core Slide (Page 9) —— */
.reveal .slides section.page-agent-core .slide-content {
    gap: 34px;
}

.reveal .slides section.page-agent-core .text-block {
    flex: 1;
}

.reveal .slides section.page-agent-core .img-block {
    flex: 1.15;
}

.reveal .slides section.page-agent-core .img-block img {
    width: min(100%, 760px);
    max-width: 760px;
    max-height: 540px;
}

/* —— Stanford Town Slide (Page 11) —— */
.reveal .slides section.page-stanford-town h3 {
    font-size: 1.2em;
    margin-bottom: 0.45em;
}

.reveal .slides section.page-stanford-town .slide-content {
    align-items: flex-start;
    gap: 32px;
}

.reveal .slides section.page-stanford-town .text-block {
    flex: 1.08;
    font-size: 0.82em;
}

.reveal .slides section.page-stanford-town .img-block {
    flex: 0.92;
    align-items: flex-start;
}

.reveal .slides section.page-stanford-town .img-block img {
    max-height: 430px;
}

.reveal .slides section.page-stanford-town .stanford-keyline {
    margin-bottom: 10px !important;
    line-height: 1.45;
    color: var(--text-secondary);
}

.reveal .slides section.page-stanford-town .stanford-events {
    list-style: none;
    margin: 0;
    padding-left: 0;
}

.reveal .slides section.page-stanford-town .stanford-events li {
    margin-bottom: 8px;
    padding: 10px 12px 10px 14px;
    border-left: 3px solid var(--accent);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.04);
    line-height: 1.38;
}

.reveal .slides section.page-stanford-town .stanford-events li::before {
    content: none !important;
}

.reveal .slides section.page-stanford-town .stanford-tag {
    display: inline-block;
    margin-right: 8px;
    padding: 2px 8px;
    border-radius: 999px;
    background: rgba(0, 229, 255, 0.14);
    color: var(--primary);
    font-size: 0.82em;
    font-weight: 700;
}

.reveal .slides section.page-stanford-town .stanford-warning {
    margin-top: 10px;
    padding: 10px 14px;
    border-radius: 10px;
    border: 1px solid rgba(224, 64, 251, 0.45);
    background: rgba(224, 64, 251, 0.08);
}

.reveal .slides section.page-stanford-town .stanford-warning p {
    margin: 0;
    line-height: 1.42;
}

/* —— Chapter 1 Page 14/15 —— */
.reveal .slides section.page14-scenes .slide-content {
    align-items: flex-start;
}

.reveal .slides section.page14-scenes .text-block {
    flex: 1;
    font-size: 0.8em;
}

.reveal .slides section.page14-scenes .text-block ul li {
    margin-bottom: 0.28em;
    line-height: 1.35;
}

.reveal .slides section.page14-scenes .scene-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px 14px;
    padding-left: 0;
    margin-top: 6px;
}

.reveal .slides section.page14-scenes .scene-grid li {
    margin-bottom: 0;
    padding: 7px 10px;
    border-radius: 8px;
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
    line-height: 1.32;
}

.reveal .slides section.page14-scenes .scene-grid li::before {
    content: none !important;
}

.reveal .slides section.page15-full-image .slide-content {
    height: 100%;
    justify-content: center;
    align-items: center;
}

.reveal .slides section.page15-full-image .img-block {
    flex: 1;
    width: 100%;
}

.reveal .slides section.page15-full-image .img-block img {
    width: min(100%, 1500px);
    max-width: 1500px;
    max-height: 86vh;
}

/* —— Chapter 1 Standardization (V1) —— */
.reveal .chapter1-slides section>h2,
.reveal .chapter1-slides section>h3,
.reveal .chapter1-slides section>.subtitle {
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter1-slides section .slide-content {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.reveal .chapter1-slides .lead-paragraph {
    margin-bottom: var(--space-subtitle-bottom) !important;
}

.reveal .chapter1-slides .scene-lead {
    margin-top: var(--space-subtitle-bottom) !important;
    margin-bottom: 8px !important;
    font-weight: 700;
    color: var(--accent);
}

.reveal .chapter1-slides .video-flag {
    display: inline-flex;
    align-items: center;
    margin-left: 10px;
    padding: 3px 10px;
    border-radius: 999px;
    border: 1px solid rgba(0, 229, 255, 0.34);
    background: rgba(0, 229, 255, 0.12);
    color: var(--primary);
    font-size: 0.48em;
    font-weight: 700;
    letter-spacing: 0.01em;
    vertical-align: middle;
    transform: translateY(-1px);
    white-space: nowrap;
}

/* —— Chapter 2 Standardization (V1) —— */
.reveal .chapter2-slides section>h2,
.reveal .chapter2-slides section>h3,
.reveal .chapter2-slides section>.subtitle {
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter2-slides section .slide-content {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.reveal .chapter2-slides .lead-paragraph {
    margin-bottom: var(--space-subtitle-bottom) !important;
}

.reveal .chapter2-slides .question-lead {
    font-size: 1.02em;
    margin-bottom: 10px !important;
}

.reveal .chapter2-slides .term-lead {
    margin-bottom: 8px !important;
}

.reveal .chapter2-slides .case-lead {
    margin-top: 8px !important;
    margin-bottom: 6px !important;
}

.reveal .chapter2-slides .video-flag {
    display: inline-flex;
    align-items: center;
    margin-left: 10px;
    padding: 3px 10px;
    border-radius: 999px;
    border: 1px solid rgba(0, 229, 255, 0.34);
    background: rgba(0, 229, 255, 0.12);
    color: var(--primary);
    font-size: 0.48em;
    font-weight: 700;
    letter-spacing: 0.01em;
    vertical-align: middle;
    transform: translateY(-1px);
    white-space: nowrap;
}

/* —— Chapter 3 Standardization (V1.2) —— */
.reveal .chapter3-slides section>h2,
.reveal .chapter3-slides section>h3,
.reveal .chapter3-slides section>.subtitle {
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter3-slides section .slide-content {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.reveal .chapter3-slides .lead-paragraph {
    margin-bottom: var(--space-subtitle-bottom) !important;
}

.reveal .chapter3-slides .role-note {
    margin-top: 12px !important;
}

/* —— Chapter 4 Standardization (V1.2) —— */
.reveal .chapter4-slides section>h2,
.reveal .chapter4-slides section>h3,
.reveal .chapter4-slides section>.subtitle {
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter4-slides section .slide-content {
    width: min(100%, var(--content-max-two-col));
    margin: 0 auto;
}

.reveal .chapter4-slides .ai-question-subtitle {
    font-size: 1.4em;
    margin-bottom: 40px !important;
    color: var(--text-secondary);
}

.reveal .chapter4-slides .ai-question-main {
    font-size: 2.2em;
    background: linear-gradient(135deg, #ff6b6b, #ee5a24);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.reveal .chapter4-slides .closing-quote {
    margin: 30px 0 !important;
    line-height: 1.7;
    font-size: 1.05em;
}

.reveal .chapter4-slides .final-subtitle {
    margin-top: 16px !important;
}

.reveal .chapter4-slides .final-nav-end {
    margin-top: 50px !important;
}

/* —— Chapter 1 Page 19 (Yiwu Digital Boss Lady) —— */
.reveal .slides section.page19-yiwu h3 {
    font-size: clamp(1.02em, 2.2vw, 1.36em);
    line-height: 1.22;
}

.reveal .slides section.page19-yiwu .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page19-yiwu .text-block {
    font-size: 0.84em;
}

.reveal .slides section.page19-yiwu .img-block {
    flex: 0.9;
}

.reveal .slides section.page19-yiwu .yiwu-video {
    width: min(100%, 640px);
    max-height: 500px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-glow);
    background: rgba(7, 8, 12, 0.62);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
    object-fit: contain;
}

/* —— Chapter 1 Page 21 (Xiaomi Embodied Robot) —— */
.reveal .slides section.page21-xiaomi .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page21-xiaomi .text-block {
    font-size: 0.84em;
}

.reveal .slides section.page21-xiaomi .img-block {
    flex: 0.9;
}

.reveal .slides section.page21-xiaomi .xiaomi-robot-video {
    width: min(100%, 640px);
    max-height: 500px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-glow);
    background: rgba(7, 8, 12, 0.62);
    box-shadow:
        0 4px 6px rgba(0, 0, 0, 0.4),
        0 0 50px var(--primary-glow);
    object-fit: contain;
}

/* —— Chapter 1 Page 24 (World Model) —— */
.reveal .slides section.page24-worldmodel .text-block {
    font-size: 0.8em;
}

.reveal .slides section.page24-worldmodel .text-block ul li {
    line-height: 1.35;
    margin-bottom: 0.34em;
}

/* —— Chapter 1 Page 26 (Space Computing) —— */
.reveal .slides section.page26-spacecompute .text-block {
    font-size: 0.78em;
}

.reveal .slides section.page26-spacecompute .text-block ul li {
    line-height: 1.32;
    margin-bottom: 0.3em;
}

/* —— Chapter 2 Page 27 (Turing Test) —— */
.reveal .slides section.page27-turing h3 {
    font-size: 1.26em;
    margin-bottom: 0.5em;
}

.reveal .slides section.page27-turing .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page27-turing .text-block {
    flex: 1.16;
    font-size: 0.88em;
}

.reveal .slides section.page27-turing .text-block p {
    line-height: 1.42;
}

.reveal .slides section.page27-turing .turing-core-list,
.reveal .slides section.page27-turing .turing-case-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page27-turing .turing-core-list li,
.reveal .slides section.page27-turing .turing-case-list li {
    margin-bottom: 0.26em;
    line-height: 1.38;
}

.reveal .slides section.page27-turing .img-block {
    flex: 0.92;
    align-items: center;
}

.reveal .slides section.page27-turing .img-block img {
    max-height: 460px;
}

/* —— Chapter 2 Page 28 (Origins & Pioneers) —— */
.reveal .slides section.page28-origins h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page28-origins .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page28-origins .text-block {
    flex: 1.16;
    font-size: 0.84em;
}

.reveal .slides section.page28-origins .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page28-origins .origins-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page28-origins .origins-list li {
    margin-bottom: 0.24em;
    line-height: 1.36;
}

.reveal .slides section.page28-origins .origins-list li .highlight {
    display: inline-block;
    margin-bottom: 1px;
}

.reveal .slides section.page28-origins .img-block {
    flex: 0.92;
    align-items: center;
}

.reveal .slides section.page28-origins .img-block img {
    max-height: 440px;
}

/* —— Chapter 2 Page 29 (AI Winters) —— */
.reveal .slides section.page29-winters h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page29-winters .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page29-winters .text-block {
    flex: 1.16;
    font-size: 0.86em;
}

.reveal .slides section.page29-winters .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page29-winters .winter-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page29-winters .winter-list li {
    margin-bottom: 0.25em;
    line-height: 1.36;
}

.reveal .slides section.page29-winters .img-block {
    flex: 0.92;
    align-items: center;
}

.reveal .slides section.page29-winters .img-block img {
    max-height: 460px;
}

/* —— Chapter 2 Page 30 (AlexNet) —— */
.reveal .slides section.page30-alexnet h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page30-alexnet .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page30-alexnet .text-block {
    flex: 1.2;
    font-size: 0.9em;
}

.reveal .slides section.page30-alexnet .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page30-alexnet .alexnet-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page30-alexnet .alexnet-list li {
    margin-bottom: 0.25em;
    line-height: 1.36;
}

.reveal .slides section.page30-alexnet .img-block {
    flex: 0.88;
    align-items: center;
}

.reveal .slides section.page30-alexnet .img-block img {
    max-height: 420px;
}

.reveal .slides section.page30-alexnet .page30-image-stack {
    width: min(100%, 520px);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.reveal .slides section.page30-alexnet .page30-image-stack img {
    width: 100%;
    max-height: 205px;
    object-fit: contain;
}

/* —— Chapter 2 Page 31 (Attention/Transformer) —— */
.reveal .slides section.page31-attention h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page31-attention .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page31-attention .text-block {
    flex: 1.18;
    font-size: 0.84em;
}

.reveal .slides section.page31-attention .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page31-attention .attention-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page31-attention .attention-list li {
    margin-bottom: 0.24em;
    line-height: 1.36;
}

.reveal .slides section.page31-attention .img-block {
    flex: 0.9;
    align-items: center;
}

.reveal .slides section.page31-attention .img-block img {
    max-height: 440px;
}

/* —— Chapter 2 Page 32 (Next-Token / Black Box / Scaling) —— */
.reveal .slides section.page32-nexttoken h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page32-nexttoken .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page32-nexttoken .text-block {
    flex: 1.18;
    font-size: 0.86em;
}

.reveal .slides section.page32-nexttoken .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page32-nexttoken .nexttoken-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page32-nexttoken .nexttoken-list li {
    margin-bottom: 0.24em;
    line-height: 1.36;
}

.reveal .slides section.page32-nexttoken .img-block {
    flex: 0.9;
    align-items: center;
}

.reveal .slides section.page32-nexttoken .img-block img {
    max-height: 440px;
}

/* —— Chapter 2 Page 33 (Singularity) —— */
.reveal .slides section.page33-singularity h3 {
    font-size: 1.24em;
    margin-bottom: 0.48em;
}

.reveal .slides section.page33-singularity .slide-content {
    align-items: center;
    gap: 40px;
}

.reveal .slides section.page33-singularity .text-block {
    flex: 1.18;
    font-size: 0.84em;
}

.reveal .slides section.page33-singularity .text-block p {
    line-height: 1.4;
}

.reveal .slides section.page33-singularity .singularity-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page33-singularity .singularity-list li {
    margin-bottom: 0.24em;
    line-height: 1.36;
}

.reveal .slides section.page33-singularity .img-block {
    flex: 0.9;
    align-items: center;
}

.reveal .slides section.page33-singularity .img-block img {
    max-height: 440px;
}

/* —— Chapter 3 Report Slides (Formal Style) —— */
.reveal .chapter3-slides section.report-slide h3 {
    font-size: 1.18em;
    margin-bottom: 0.56em;
    text-align: center;
    width: min(100%, var(--content-max-single));
    margin-left: auto;
    margin-right: auto;
}

.reveal .chapter3-slides section.report-slide .slide-content {
    align-items: center;
    gap: 42px;
}

.reveal .chapter3-slides section.report-slide .text-block {
    flex: 1.05;
    font-size: 0.95em;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.reveal .chapter3-slides section.report-slide .text-block p {
    line-height: 1.42;
}

.reveal .chapter3-slides section.report-slide .text-block ul {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .chapter3-slides section.report-slide .text-block ul li {
    margin-bottom: 0.28em;
    line-height: 1.4;
}

.reveal .chapter3-slides section.report-slide .img-block {
    flex: 0.95;
    align-items: center;
}

.reveal .chapter3-slides section.report-slide .img-block img {
    width: min(100%, 860px);
    max-height: 540px;
    object-fit: contain;
}

/* —— Chapter 3 Page 48 (Org Future) —— */
.reveal .slides section.page48-org-future .slide-content {
    align-items: center;
    gap: 32px;
}

.reveal .slides section.page48-org-future .text-block {
    flex: 1.08;
    font-size: 0.9em;
}

.reveal .slides section.page48-org-future .img-block {
    flex: 0.92;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    justify-content: center;
    gap: 8px;
}

.reveal .slides section.page48-org-future .future-org-thumb {
    width: min(100%, 700px);
    max-height: 360px;
    object-fit: contain;
    cursor: zoom-in;
    transition: var(--transition-base);
}

.reveal .slides section.page48-org-future .future-org-tip {
    margin: 0 !important;
    font-size: 0.64em;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}

/* —— Chapter 4 Page 45 (Productivity VS) —— */
.reveal .slides section.page45-productivity-vs h3 {
    margin-bottom: 0.75em;
}

.reveal .slides section.page45-productivity-vs .vs-compare-wrap {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    align-items: stretch;
    gap: 20px;
    width: min(100%, 1220px);
    margin: 8px auto 0;
}

.reveal .slides section.page45-productivity-vs .vs-card {
    padding: 28px 30px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.04);
    box-shadow:
        0 6px 20px rgba(0, 0, 0, 0.28),
        0 0 26px rgba(0, 229, 255, 0.08);
    text-align: left;
}

.reveal .slides section.page45-productivity-vs .vs-card.vs-before {
    border-color: rgba(0, 229, 255, 0.3);
    background:
        linear-gradient(160deg, rgba(0, 229, 255, 0.12), rgba(0, 229, 255, 0.03) 45%, rgba(255, 255, 255, 0.02) 100%);
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.3),
        0 0 30px rgba(0, 229, 255, 0.14);
}

.reveal .slides section.page45-productivity-vs .vs-card.vs-after {
    border-color: rgba(224, 64, 251, 0.32);
    background:
        linear-gradient(160deg, rgba(224, 64, 251, 0.13), rgba(224, 64, 251, 0.03) 45%, rgba(255, 255, 255, 0.02) 100%);
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.3),
        0 0 30px rgba(224, 64, 251, 0.14);
}

.reveal .slides section.page45-productivity-vs .vs-card-title {
    margin: 0 0 12px !important;
    font-size: 1.02em;
    font-weight: 700;
    color: var(--primary);
}

.reveal .slides section.page45-productivity-vs .vs-card.vs-after .vs-card-title {
    color: var(--accent);
}

.reveal .slides section.page45-productivity-vs .vs-card-list {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page45-productivity-vs .vs-card-list li {
    margin-bottom: 0.34em;
    line-height: 1.45;
    font-size: 0.9em;
    color: var(--text-primary);
}

.reveal .slides section.page45-productivity-vs .vs-key {
    font-weight: 700;
    letter-spacing: 0.005em;
}

.reveal .slides section.page45-productivity-vs .vs-key-blue {
    color: #7fefff;
    text-shadow: 0 0 14px rgba(0, 229, 255, 0.35);
}

.reveal .slides section.page45-productivity-vs .vs-key-purple {
    color: #f2a4ff;
    text-shadow: 0 0 14px rgba(224, 64, 251, 0.35);
}

.reveal .slides section.page45-productivity-vs .vs-core {
    align-self: center;
    font-size: clamp(2.2em, 6vw, 4.2em);
    font-weight: 800;
    letter-spacing: 0.12em;
    color: #ffffff;
    text-shadow:
        0 0 16px rgba(224, 64, 251, 0.65),
        0 0 34px rgba(0, 229, 255, 0.45);
    animation: vsPulse 1.1s ease-in-out infinite;
    user-select: none;
}

@keyframes vsPulse {
    0%,
    100% {
        opacity: 1;
        transform: scale(1);
    }

    50% {
        opacity: 0.35;
        transform: scale(1.08);
    }
}

/* —— Chapter 4 Page 46 (Engineer Levels) —— */
.reveal .slides section.page46-engineer-levels h3 {
    margin-bottom: 0.4em;
}

.reveal .slides section.page46-engineer-levels .level-intro {
    margin-bottom: 12px !important;
    font-size: 0.88em;
}

.reveal .slides section.page46-engineer-levels .levels-table-wrap {
    width: min(100%, 1240px);
    margin: 0 auto;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
    box-shadow:
        0 6px 20px rgba(0, 0, 0, 0.28),
        0 0 20px rgba(0, 229, 255, 0.08);
    overflow: hidden;
}

.reveal .slides section.page46-engineer-levels .levels-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.reveal .slides section.page46-engineer-levels .levels-table th,
.reveal .slides section.page46-engineer-levels .levels-table td {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 8px 10px;
    text-align: left;
    vertical-align: top;
    line-height: 1.35;
}

.reveal .slides section.page46-engineer-levels .levels-table thead th {
    font-size: 0.74em;
    font-weight: 700;
    color: var(--primary);
    background: rgba(0, 229, 255, 0.06);
}

.reveal .slides section.page46-engineer-levels .levels-table tbody td {
    font-size: 0.68em;
    color: var(--text-primary);
}

.reveal .slides section.page46-engineer-levels .levels-table tbody tr:nth-child(even) td {
    background: rgba(255, 255, 255, 0.02);
}

.reveal .slides section.page46-engineer-levels .levels-table th:nth-child(1),
.reveal .slides section.page46-engineer-levels .levels-table td:nth-child(1) {
    width: 10%;
    font-weight: 700;
    color: var(--accent);
}

.reveal .slides section.page46-engineer-levels .levels-table th:nth-child(2),
.reveal .slides section.page46-engineer-levels .levels-table td:nth-child(2) {
    width: 16%;
    font-weight: 600;
}

.reveal .slides section.page46-engineer-levels .levels-table th:nth-child(3),
.reveal .slides section.page46-engineer-levels .levels-table td:nth-child(3) {
    width: 74%;
}

/* —— Chapter 4 Page 47 (Xiong Ladder) —— */
.reveal .slides section.page47-xiong-ladder h3 {
    margin-bottom: 0.5em;
}

.reveal .slides section.page47-xiong-ladder .xiong-intro {
    margin-bottom: 16px !important;
    font-size: 0.76em;
    line-height: 1.4;
}

.reveal .slides section.page47-xiong-ladder .xiong-table-wrap {
    width: min(100%, 1240px);
    margin: 4px auto 0;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.03);
    overflow: hidden;
}

.reveal .slides section.page47-xiong-ladder .xiong-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.reveal .slides section.page47-xiong-ladder .xiong-table th,
.reveal .slides section.page47-xiong-ladder .xiong-table td {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 7px 9px;
    text-align: left;
    vertical-align: top;
    line-height: 1.35;
}

.reveal .slides section.page47-xiong-ladder .xiong-table thead th {
    font-size: 0.7em;
    font-weight: 700;
    color: var(--primary);
    background: rgba(0, 229, 255, 0.06);
}

.reveal .slides section.page47-xiong-ladder .xiong-table tbody td {
    font-size: 0.62em;
    color: var(--text-primary);
}

.reveal .slides section.page47-xiong-ladder .xiong-table tbody tr:nth-child(even) td {
    background: rgba(255, 255, 255, 0.02);
}

.reveal .slides section.page47-xiong-ladder .xiong-table th:nth-child(1),
.reveal .slides section.page47-xiong-ladder .xiong-table td:nth-child(1) {
    width: 16%;
}

.reveal .slides section.page47-xiong-ladder .xiong-table th:nth-child(2),
.reveal .slides section.page47-xiong-ladder .xiong-table td:nth-child(2) {
    width: 16%;
}

.reveal .slides section.page47-xiong-ladder .xiong-table th:nth-child(3),
.reveal .slides section.page47-xiong-ladder .xiong-table td:nth-child(3) {
    width: 68%;
}

.reveal .slides section.page47-xiong-ladder .xiong-insight {
    margin: 18px auto 0;
    width: min(100%, 1240px);
    border: 1px solid rgba(224, 64, 251, 0.4);
    border-radius: 12px;
    background: rgba(224, 64, 251, 0.08);
    padding: 12px 16px;
    display: grid;
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 14px;
    align-items: stretch;
}

.reveal .slides section.page47-xiong-ladder .xiong-insight-left {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 10px 12px;
    border-radius: 10px;
    background: rgba(224, 64, 251, 0.12);
    border: 1px solid rgba(224, 64, 251, 0.35);
    margin: 0;
    font-size: 0.88em;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 0.02em;
}

.reveal .slides section.page47-xiong-ladder .xiong-insight-right {
    min-width: 0;
}

.reveal .slides section.page47-xiong-ladder .xiong-insight-right ul {
    margin: 0;
    padding-left: 1.35em;
}

.reveal .slides section.page47-xiong-ladder .xiong-insight-right ul li {
    margin-bottom: 0.16em;
    font-size: 0.72em;
    line-height: 1.36;
}

/* —— Chapter 4 Page 48 (Industry Rebuild) —— */
.reveal .slides section.page48-industry-rebuild h3 {
    margin-bottom: 0.5em;
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-subtitle {
    margin-bottom: 16px !important;
    font-size: 0.92em;
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table-wrap {
    width: min(100%, 1240px);
    margin: 4px auto 0;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.03);
    overflow: hidden;
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table td {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 12px 14px;
    text-align: left;
    vertical-align: top;
    line-height: 1.46;
    font-size: 0.7em;
    color: var(--text-primary);
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table tr:nth-child(even) td {
    background: rgba(255, 255, 255, 0.02);
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table td:first-child {
    width: 14%;
    font-size: 0.76em;
    color: var(--accent);
    font-weight: 700;
    letter-spacing: 0.01em;
}

.reveal .slides section.page48-industry-rebuild .industry-rebuild-table td:last-child {
    width: 86%;
}

/* —— Chapter 4 Page 49 (Preparation) —— */
.reveal .slides section.page49-prep h3 {
    margin-bottom: 0.35em;
}

.reveal .slides section.page49-prep .prep-subtitle {
    margin-bottom: 12px !important;
    font-size: 0.88em;
}

.reveal .slides section.page49-prep .prep-table-wrap {
    width: min(100%, 1180px);
    margin: 0 auto;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.03);
    overflow: hidden;
}

.reveal .slides section.page49-prep .prep-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.reveal .slides section.page49-prep .prep-table th,
.reveal .slides section.page49-prep .prep-table td {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 10px 12px;
    text-align: left;
    vertical-align: top;
    line-height: 1.4;
}

.reveal .slides section.page49-prep .prep-table thead th {
    font-size: 0.76em;
    font-weight: 700;
    color: var(--primary);
    background: rgba(0, 229, 255, 0.06);
}

.reveal .slides section.page49-prep .prep-table tbody td {
    font-size: 0.7em;
    color: var(--text-primary);
}

.reveal .slides section.page49-prep .prep-table tbody tr:nth-child(even) td {
    background: rgba(255, 255, 255, 0.02);
}

.reveal .slides section.page49-prep .prep-table th:nth-child(1),
.reveal .slides section.page49-prep .prep-table td:nth-child(1) {
    width: 30%;
}

.reveal .slides section.page49-prep .prep-table th:nth-child(2),
.reveal .slides section.page49-prep .prep-table td:nth-child(2) {
    width: 16%;
    text-align: center;
    letter-spacing: 0.05em;
}

.reveal .slides section.page49-prep .prep-table th:nth-child(3),
.reveal .slides section.page49-prep .prep-table td:nth-child(3) {
    width: 54%;
}

/* —— Chapter 4 Page 50 (AI Amplifier) —— */
.reveal .slides section.page50-ai-amplifier h3 {
    margin-bottom: 0.35em;
}

.reveal .slides section.page50-ai-amplifier .amplifier-subtitle {
    margin-bottom: 10px !important;
    font-size: 0.88em;
}

.reveal .slides section.page50-ai-amplifier .amplifier-quote {
    margin: 0 auto 12px;
    width: min(100%, 980px);
    padding: 12px 16px;
    border-left: 4px solid var(--accent);
    border-radius: 10px;
    background: rgba(224, 64, 251, 0.08);
    text-align: left;
}

.reveal .slides section.page50-ai-amplifier .amplifier-quote strong {
    font-size: 0.98em;
    line-height: 1.45;
    color: var(--text-primary);
}

.reveal .slides section.page50-ai-amplifier .amplifier-formula-card {
    width: min(100%, 980px);
    margin: 0 auto 12px;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(0, 229, 255, 0.35);
    background: rgba(0, 229, 255, 0.08);
    text-align: center;
}

.reveal .slides section.page50-ai-amplifier .amplifier-formula-label {
    margin: 0 0 6px !important;
    font-size: 0.72em;
    color: var(--primary);
    font-weight: 700;
    letter-spacing: 0.03em;
}

.reveal .slides section.page50-ai-amplifier .amplifier-formula {
    margin: 0 !important;
    font-size: 1.02em;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: 0.01em;
}

.reveal .slides section.page50-ai-amplifier .amplifier-list {
    width: min(100%, 980px);
    margin: 0 auto;
    padding-left: 1.35em;
}

.reveal .slides section.page50-ai-amplifier .amplifier-list li {
    margin-bottom: 0.34em;
    font-size: 0.82em;
    line-height: 1.42;
}

/* —— Chapter 4 Page 51 (AI Roadmap) —— */
.reveal .slides section.page51-roadmap h3 {
    margin-bottom: 0.32em;
}

.reveal .slides section.page51-roadmap .roadmap-block {
    width: min(100%, 1180px);
    margin: 0 auto 10px;
}

.reveal .slides section.page51-roadmap .roadmap-heading {
    margin: 0 0 8px !important;
    font-size: 0.8em;
    font-weight: 700;
    color: var(--primary);
}

.reveal .slides section.page51-roadmap .roadmap-stage-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.reveal .slides section.page51-roadmap .roadmap-stage-card {
    padding: 12px 14px;
    border-radius: 12px;
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
    text-align: left;
}

.reveal .slides section.page51-roadmap .roadmap-stage-title {
    margin: 0 0 6px !important;
    font-size: 0.72em;
    font-weight: 700;
    color: var(--accent);
    line-height: 1.3;
}

.reveal .slides section.page51-roadmap .roadmap-stage-list {
    margin: 0;
    padding-left: 1.2em;
}

.reveal .slides section.page51-roadmap .roadmap-stage-list li {
    margin-bottom: 0.14em;
    font-size: 0.62em;
    line-height: 1.34;
}

.reveal .slides section.page51-roadmap .roadmap-tools-wrap {
    width: min(100%, 1180px);
    margin: 0 auto;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.03);
    overflow: hidden;
}

.reveal .slides section.page51-roadmap .roadmap-tools-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.reveal .slides section.page51-roadmap .roadmap-tools-table th,
.reveal .slides section.page51-roadmap .roadmap-tools-table td {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 9px 12px;
    text-align: left;
    vertical-align: top;
    line-height: 1.36;
}

.reveal .slides section.page51-roadmap .roadmap-tools-table thead th {
    font-size: 0.72em;
    font-weight: 700;
    color: var(--primary);
    background: rgba(0, 229, 255, 0.06);
}

.reveal .slides section.page51-roadmap .roadmap-tools-table tbody td {
    font-size: 0.64em;
}

.reveal .slides section.page51-roadmap .roadmap-tools-table tbody tr:nth-child(even) td {
    background: rgba(255, 255, 255, 0.02);
}

.reveal .slides section.page51-roadmap .roadmap-tools-table th:nth-child(1),
.reveal .slides section.page51-roadmap .roadmap-tools-table td:nth-child(1) {
    width: 24%;
}

.reveal .slides section.page51-roadmap .roadmap-tools-table th:nth-child(2),
.reveal .slides section.page51-roadmap .roadmap-tools-table td:nth-child(2) {
    width: 76%;
}

.reveal .slides section.page51-roadmap .roadmap-highlights {
    width: min(100%, 1180px);
    margin: 10px auto 8px;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.reveal .slides section.page51-roadmap .roadmap-highlight-item {
    padding: 10px 12px;
    border-radius: 12px;
    border: 1px solid rgba(224, 64, 251, 0.35);
    background: rgba(224, 64, 251, 0.08);
    text-align: left;
}

.reveal .slides section.page51-roadmap .roadmap-highlight-item p {
    margin: 0;
    font-size: 0.62em;
    line-height: 1.36;
}

.reveal .slides section.page51-roadmap .roadmap-trend {
    width: min(100%, 1180px);
    margin: 0 auto;
    font-size: 0.62em;
    line-height: 1.36;
    color: var(--text-secondary);
}

/* —— Chapter 4 Page 52 (Practice Tips) —— */
.reveal .slides section.page52-practice-tips h3 {
    margin-bottom: 0.35em;
}

.reveal .slides section.page52-practice-tips .practice-tips-grid {
    width: min(100%, 1180px);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
}

.reveal .slides section.page52-practice-tips .practice-tip-card {
    padding: 14px 14px 12px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
    text-align: left;
}

.reveal .slides section.page52-practice-tips .practice-tip-title {
    margin: 0 0 8px !important;
    font-size: 0.78em;
    font-weight: 700;
    color: var(--accent);
}

.reveal .slides section.page52-practice-tips .practice-tip-list {
    margin: 0;
    padding-left: 1.2em;
}

.reveal .slides section.page52-practice-tips .practice-tip-list li {
    margin-bottom: 0.22em;
    font-size: 0.64em;
    line-height: 1.36;
}

/* —— Image Lightbox —— */
.slide-image-lightbox {
    position: fixed;
    inset: 0;
    z-index: 10000;
    background: rgba(2, 4, 10, 0.86);
    display: none;
    align-items: center;
    justify-content: center;
    padding: 38px 24px 24px;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}

.slide-image-lightbox.is-open {
    display: flex;
}

.slide-image-lightbox img {
    max-width: min(96vw, 1500px);
    max-height: 88vh;
    width: auto;
    height: auto;
    border-radius: 14px;
    border: 1px solid var(--border-glow);
    box-shadow:
        0 10px 40px rgba(0, 0, 0, 0.6),
        0 0 60px rgba(0, 229, 255, 0.24);
}

.slide-image-lightbox-close {
    position: absolute;
    right: 16px;
    top: 12px;
    width: 40px;
    height: 40px;
    border: 1px solid var(--border-subtle);
    border-radius: 999px;
    background: rgba(7, 8, 12, 0.82);
    color: var(--text-primary);
    font-size: 26px;
    line-height: 1;
    cursor: pointer;
    transition: var(--transition-base);
}

.slide-image-lightbox-close:hover {
    border-color: var(--primary);
    box-shadow: 0 0 20px var(--primary-glow);
}

/* —— Lists —— */
.reveal ul {
    list-style: none;
    padding-left: 1.6em;
    margin: 0;
}

.reveal ul li {
    position: relative;
    margin-bottom: 0.5em;
    padding-left: 0;
}

.reveal ul li::before {
    content: "▸";
    position: absolute;
    left: -1.4em;
    color: var(--primary);
    font-size: 0.9em;
    top: 0.08em;
}

.reveal ol {
    padding-left: 1.8em;
}

.reveal ol li {
    margin-bottom: 0.5em;
}

/* —— Cards & Boxes —— */
.glass-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 30px;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.matrix-box {
    border: 1px solid var(--border-glow);
    padding: 20px 28px;
    margin: 12px auto;
    border-radius: var(--radius-md);
    background: rgba(0, 229, 255, 0.04);
    box-shadow: 0 0 20px rgba(0, 229, 255, 0.06);
    max-width: 700px;
    transition: var(--transition-base);
}

.matrix-box:hover {
    border-color: var(--primary);
    box-shadow: 0 0 40px rgba(0, 229, 255, 0.15);
}

/* —— Floating Home Button —— */
.home-btn {
    position: fixed;
    top: 18px;
    left: 18px;
    z-index: 9999;
    background: rgba(7, 8, 12, 0.7);
    color: var(--text-secondary);
    padding: 8px 18px;
    border-radius: 100px;
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.02em;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    transition: var(--transition-base);
    font-family: 'Inter', 'Noto Sans SC', sans-serif;
}

.home-btn:hover {
    background: var(--primary);
    color: var(--bg-deep);
    border-color: var(--primary);
    box-shadow: 0 0 25px var(--primary-glow);
}

.home-btn:focus-visible,
.nav-end a:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 3px;
    box-shadow: 0 0 0 4px rgba(0, 229, 255, 0.2);
}

/* —— Chapter End Navigation —— */
.nav-end {
    display: flex;
    gap: 24px;
    justify-content: center;
    align-items: center;
    margin-top: 40px;
}

.nav-end a {
    padding: 14px 32px;
    border-radius: 100px;
    text-decoration: none;
    font-size: 0.65em;
    font-weight: 600;
    transition: var(--transition-base);
    letter-spacing: 0.02em;
}

.nav-end .nav-home {
    background: var(--bg-card);
    color: var(--text-secondary);
    border: 1px solid var(--border-subtle);
}

.nav-end .nav-home:hover {
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

.nav-end .nav-next {
    background: linear-gradient(135deg, var(--primary), #a78bfa);
    color: var(--bg-deep);
    border: none;
    box-shadow: 0 4px 20px var(--primary-glow);
}

.nav-end .nav-next:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px var(--primary-glow);
}

/* —— Cover Slide Overlay —— */
.cover-overlay {
    background: rgba(7, 8, 12, 0.75);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 50px 60px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-subtle);
}

/* —— Placeholder for Missing Images —— */
.placeholder-img {
    background: var(--bg-card);
    border: 1px dashed var(--border-glow);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    height: 350px;
    color: var(--text-dim);
    font-size: 0.8em;
}

/* —— Image + Video Stack —— */
.media-stack {
    display: flex;
    flex-direction: column;
    gap: 14px;
    width: min(100%, 640px);
}

.media-item {
    padding: 10px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
}

.media-label {
    margin: 0 0 8px 0 !important;
    font-size: 0.58em;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}

.media-stack img,
.media-stack video {
    display: block;
    width: 100%;
    max-height: 220px;
    border-radius: 10px;
    border: 1px solid var(--border-glow);
    object-fit: contain;
    background: rgba(7, 8, 12, 0.6);
}

/* —— Fragment Animations —— */
.reveal .fragment {
    transition: opacity 0.35s var(--ease-standard), transform 0.35s var(--ease-standard);
}

/* —— Slide Number Styling —— */
.reveal .slide-number {
    font-family: 'Inter', sans-serif;
    font-size: 12px;
    color: var(--text-dim);
    background: rgba(7, 8, 12, 0.6);
    padding: 4px 10px;
    border-radius: 8px;
    border: 1px solid var(--border-subtle);
}

/* —— Progress Bar —— */
.reveal .progress {
    height: 3px;
    color: var(--primary);
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .img-block img:hover,
    .nav-end .nav-next:hover {
        transform: none;
    }
}

/* —— Responsive Tweaks —— */
@media (max-width: 768px) {
    :root {
        --safe-x: 24px;
        --safe-y: 24px;
        --space-title-bottom: 12px;
        --space-subtitle-bottom: 10px;
        --space-block-gap: 12px;
        --space-list-item: 4px;
    }

    .slide-content {
        flex-direction: column;
    }

    .reveal h1 {
        font-size: 2em;
    }

    .reveal h3 {
        font-size: 1.2em;
    }

    .reveal .chapter0-slides .page3-quote {
        font-size: 1.02em;
    }

    .reveal .chapter0-slides .transition-title {
        font-size: 1.28em;
        line-height: 1.42;
    }

    .reveal .chapter0-slides .transition-subline {
        font-size: 0.96em;
    }

    .reveal .chapter0-slides .insight-note {
        font-size: 0.8em;
    }

    .img-block img,
    .img-block video {
        max-height: 300px;
    }

    .reveal .slides section.page-speaker-profile .text-block {
        font-size: 0.92em;
    }

    .reveal .slides section.page-speaker-profile .speaker-profile-panel {
        width: min(100%, 520px);
    }

    .reveal .slides section.page-speaker-profile .speaker-avatar img {
        max-height: 210px;
    }

    .reveal .slides section.page-speaker-profile .speaker-books img {
        max-height: 130px;
    }

    .page2-carousel {
        width: min(100%, 520px);
        height: 300px;
    }

    .page8-carousel {
        width: min(100%, 520px);
        height: 300px;
    }

    .reveal .slides section.page-human-hiring .text-block {
        font-size: 0.92em;
    }

    .reveal .slides section.page-human-hiring .img-block img {
        max-height: 240px;
    }

    .reveal .slides section.page-agent-core .img-block img {
        width: min(100%, 560px);
        max-width: 560px;
        max-height: 320px;
    }

    .reveal .slides section.page-stanford-town .text-block {
        font-size: 0.92em;
    }

    .reveal .slides section.page-stanford-town .img-block img {
        max-height: 250px;
    }

    .reveal .slides section.page14-scenes .text-block {
        font-size: 0.9em;
    }

    .reveal .slides section.page14-scenes .scene-grid {
        grid-template-columns: 1fr;
    }

    .reveal .slides section.page15-full-image .img-block img {
        width: min(100%, 96vw);
        max-width: 96vw;
        max-height: 72vh;
    }

    .reveal .slides section.page19-yiwu h3 {
        font-size: clamp(0.9em, 4.4vw, 1.08em);
    }

    .reveal .slides section.page19-yiwu .text-block {
        font-size: 0.9em;
    }

    .reveal .slides section.page19-yiwu .yiwu-video {
        width: min(100%, 520px);
        max-height: 320px;
    }

    .reveal .slides section.page21-xiaomi .text-block {
        font-size: 0.9em;
    }

    .reveal .slides section.page21-xiaomi .xiaomi-robot-video {
        width: min(100%, 520px);
        max-height: 320px;
    }

    .reveal .slides section.page24-worldmodel .text-block {
        font-size: 0.88em;
    }

    .reveal .slides section.page26-spacecompute .text-block {
        font-size: 0.86em;
    }

    .reveal .slides section.page27-turing .text-block {
        font-size: 0.9em;
    }

    .reveal .slides section.page27-turing .img-block img {
        max-height: 240px;
    }

    .reveal .slides section.page28-origins .text-block {
        font-size: 0.88em;
    }

    .reveal .slides section.page28-origins .img-block img {
        max-height: 240px;
    }

    .reveal .slides section.page29-winters .text-block {
        font-size: 0.88em;
    }

    .reveal .slides section.page29-winters .img-block img {
        max-height: 240px;
    }

    .reveal .slides section.page30-alexnet .text-block {
        font-size: 0.92em;
    }

    .reveal .slides section.page30-alexnet .img-block img {
        max-height: 240px;
    }

    .reveal .slides section.page30-alexnet .page30-image-stack {
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    .reveal .slides section.page30-alexnet .page30-image-stack img {
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    .reveal .slides section.page31-attention .img-block img {
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    .reveal .slides section.page32-nexttoken .img-block img {
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    .reveal .slides section.page33-singularity .img-block img {
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        max-height: 250px;
        width: min(100%, 560px);
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        grid-template-columns: 1fr;
        gap: 12px;
        width: min(100%, 92vw);
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        padding: 18px 18px;
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    .reveal .slides section.page48-industry-rebuild .industry-rebuild-table-wrap {
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    .reveal .slides section.page48-industry-rebuild .industry-rebuild-table {
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    .slide-image-lightbox img {
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    .media-stack {
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    .media-stack img,
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}