/* Lecture 19: training-time attack storyboards (Lecture 18 visual system). */
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.reveal .l19-slide .l19-drop.is-scene-visible { animation: l19-drop .6s cubic-bezier(.2,.9,.3,1.2) both; }
.reveal .l19-slide .l19-pulse.is-scene-visible, .reveal .l19-slide .is-scene-visible .l19-pulse { animation: l19-pulse 1.2s ease-in-out 3; transform-box: fill-box; transform-origin: center; }
.reveal .l19-slide .search-figure { margin-top: 40px; }
.reveal .l19-slide .bb-takeaway { margin-top: 18px; padding-top: 14px; }
.reveal .l19-slide .l19-sources { position: absolute; left: 76px; bottom: 26px; width: 1300px; display: grid; gap: 3px; }
.reveal .l19-slide .l19-sources .source-line { position: static; width: auto; }
/* Equation line under a storyboard. */
.reveal .l19-slide .l19-eq { width:1400px; margin:12px 0 0; color:#000f46; font-size:24px; text-align:center; }
.reveal .l19-slide .l19-eq mjx-container { margin:0 !important; }
@keyframes l19-rise { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }
@keyframes l19-drop { from { opacity: 0; transform: translateY(-40px); } to { opacity: 1; transform: none; } }
@keyframes l19-pulse { 0%,100% { transform: scale(1); } 50% { transform: scale(1.25); } }
@media (prefers-reduced-motion: reduce) {
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}
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.reveal .l19-clean-vs-flip .l19-cf-lb { transition:transform 1s ease; transform-box:view-box; transform-origin:345px 210px; }
.reveal .l19-clean-vs-flip[data-active-scene="2"] .l19-cf-lb,.reveal .l19-clean-vs-flip[data-active-scene="3"] .l19-cf-lb,.reveal .l19-clean-vs-flip[data-active-scene="4"] .l19-cf-lb,.reveal .l19-clean-vs-flip[data-active-scene="5"] .l19-cf-lb { transform:translate(-110px,0) rotate(-6deg); }
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.reveal .l19-clean-vs-flip .l19-cf-rb { transition:transform 1s ease; transform-box:view-box; transform-origin:1045px 210px; }
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.reveal .l19-frogs-optimise .l19-eq { width:1400px; margin:12px 0 0; color:#000f46; font-size:24px; text-align:center; }
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.reveal .l19-witches-brew:is([data-active-scene="4"],[data-active-scene="5"]) .l19-wb-gp { transform:rotate(-31deg); }
.reveal .l19-sponge-poisoning .l19-sp-n { fill:#f3f3f6; transition: fill .8s ease; }
.reveal .l19-sponge-poisoning .l19-sp-on { fill:#2563c9; }
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@keyframes l19-do-draw { from { stroke-dashoffset:1; } to { stroke-dashoffset:0; } }

/* Larger text for the back row. */
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.reveal .l19-slide .bb-takeaway { font-size: 28px; }
.reveal .l19-slide .l19-eq { font-size: 27px; }

/* Layout: centre the storyboard block (figure, equation, takeaway) vertically
   in the space between the lead and the reference line. */
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.reveal .slides > section.l19-slide > .kicker { align-self:flex-start; }
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.reveal .slides > section.l19-slide > .bb-takeaway { margin-top:20px; flex-shrink:0; }

/* Palette: navy + blue (normal/clean) + red (attack) + purple (second class). No teal. */
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.reveal .l19-slide .search-accepted { color:#2563c9; }
.reveal .l19-biggio-surface .l19-bs-bound { transform-box:view-box; transform-origin:330px 193px; transition:transform 1s ease; }
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/* Takeaway that appears only on the last scene. */
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.reveal .l19-frogs-threat[data-active-scene="6"] .l19-late-takeaway { visibility:visible; opacity:1; }

/* Poison Frogs threat model: use the full slide width so the six cards are larger. */
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.reveal .l19-frogs-threat .search-figure > svg { width:1448px; height:434px; }
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.reveal .l19-frogs-optimise[data-active-scene="2"] .l19-fo2-pt { transform: translate(142px,0px); }
.reveal .l19-frogs-optimise[data-active-scene="3"] .l19-fo2-pt { transform: translate(310px,0px); }
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.reveal .l19-frogs-optimise[data-active-scene="5"] .l19-fo2-pt { transform: translate(398px,0px); }
/* Slides with many references: two-column, smaller text */
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.reveal .slides > section.l19-slide.l19-bd-triggers-vision:has(.l19-sources) { padding-bottom: 104px; }
.reveal .l19-bd-dataset-urls[data-active-scene="2"] .l19-late-takeaway { visibility:visible; opacity:1; }
/* BadEncoder slide: short pipeline figure + Hugging Face stats (from Lecture 18) */
.reveal .l19-bd-badencoder .search-figure { height: 260px; margin-top: 24px; }
.reveal .l19-bd-badencoder .search-figure > svg { height: 260px; }
.reveal .l19-bd-badencoder .l19-practicality { margin-top: 18px; padding-top: 14px; flex-shrink: 0; }
.reveal .l19-bd-badencoder .l19-practicality h3 { color: var(--blue, #2563c9); }
/* Lecture 20: part dividers and late equation */
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.reveal .l20-part .composite-points { margin-top: 40px; }
.reveal .l19-d-dada .search-figure, .reveal .l19-d-dada .search-figure svg { height: 560px; }
/* Hide scene elements instantly (no fade-out flash when a slide is entered); showing still animates. */
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/* Keep the AT comparison in one position; only its PGD steps appear in place. */
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  top: 281px;
  left: 76px;
  margin: 0;
}
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.reveal.l20-deck .l19-d-at-pgd [data-scene] { transition: opacity .18s ease, visibility .18s ease; }
/* Lecture 20 readability */
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.reveal .l20-atvariants .l20-var-group { margin-top: 6px; padding: 4px 0; color: var(--blue); font-size: 20px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; border-bottom: 2px solid var(--blue); }
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.reveal .l20-atvariants .l20-var-name em { display: block; color: var(--muted, #8290aa); font-size: 18px; font-style: normal; font-weight: 600; }
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.reveal .l20-atvariants .l20-var-body p { margin: 2px 0 0; color: var(--ink-2); font-size: 20px; line-height: 1.25; }
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/* Shared APA source style (L15–18 14px/600 baseline; L18 left 76 + hanging indent). */
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  left: 76px;
  right: auto;
  bottom: 10px;
  z-index: 4;
  display: block;
  width: 1400px;
  max-width: none;
  margin: 0;
  box-sizing: border-box;
  padding: 0 0 0 1.25em;
  border: 0;
  border-bottom: 1px solid rgba(0, 15, 70, 0.28);
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  font-size: 14px;
  font-weight: 600;
  line-height: 1.25;
  text-align: left;
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  bottom: 10px;
  z-index: 4;
  display: grid;
  gap: 2px;
  width: 1400px;
  max-width: none;
  margin: 0;
  box-sizing: border-box;
  overflow: visible;
}
.reveal:is(.l20-deck, .course-deck) .l19-slide .l19-sources .source-line,
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/* Lecture 20: all input transformations share one pipeline and detail area. */
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  top: 218px;
  left: 76px;
  display: grid;
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  align-items: center;
  width: 1400px;
  height: 68px;
  color: #000f46;
  font-size: 22px;
  font-weight: 700;
}
.reveal.l20-deck .l20-preprocess-flow > span {
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  height: 68px;
  padding: 10px 16px;
  border: 2px solid #b7c3d8;
  border-radius: 10px;
  background: white;
  text-align: center;
}
.reveal.l20-deck .l20-preprocess-flow > .flow-arrow {
  padding: 0;
  border: 0;
  background: none;
  font-size: 30px;
}
.reveal.l20-deck .l20-preprocess-flow > .flow-transform {
  border-color: #2563c9;
  background: #eef4ff;
  color: #2563c9;
}
.reveal.l20-deck .l20-preprocess-flow > .flow-model {
  border-color: #000f46;
  background: #000f46;
  color: white;
}
.reveal.l20-deck .l20-preprocess > .search-figure {
  position: absolute;
  top: 306px;
  left: 76px;
  height: 445px;
  margin: 0;
}
.reveal.l20-deck .l20-preprocess > .search-figure > svg {
  height: 445px;
}
.reveal.l20-deck .l20-preprocess > .bb-takeaway {
  position: absolute;
  top: 765px;
  left: 76px;
  margin: 0;
}

/* Keep later-lecture headings clear of the corner brand. */
.reveal.course-deck h2 {
  max-width: 1320px;
}

/* Lecture 20: the same PGD computation as a graph and short pseudocode. */
.reveal.l20-deck .l19-d-at-graph > .l20-graph-code {
  display: grid;
  grid-template-columns: 680px 680px;
  gap: 40px;
  width: 1400px;
  height: 420px;
  margin: auto 0;
  flex-shrink: 0;
}
.reveal.l20-deck .l20-graph-panel,
.reveal.l20-deck .l20-pseudo-panel {
  box-sizing: border-box;
  height: 420px;
  padding: 14px;
  border: 2px solid #b7c3d8;
  border-radius: 14px;
  background: white;
  color: #000f46;
}
.reveal.l20-deck .l20-graph-head { display: flex; justify-content: space-between; align-items: center; height: 36px; font-size: 23px; }
.reveal.l20-deck .l20-graph-head strong { font-weight: 800; }
.reveal.l20-deck .l20-graph-stage { padding: 5px 12px; border-radius: 18px; background: #000f46; color: white; font-size: 19px; font-weight: 700; }
.reveal.l20-deck .l20-graph-stage-red { background: #ff4756; }
.reveal.l20-deck .l20-graph-stage-blue { background: #2563c9; }
.reveal.l20-deck .l20-graph-head { position: relative; }
.reveal.l20-deck .l20-graph-head .l20-graph-stage { position: absolute; right: 0; }
.reveal.l20-deck .l20-graph-canvas { position: relative; width: 650px; height: 288px; margin: 2px auto 0; }
.reveal.l20-deck .l20-graph-arrows { position: absolute; inset: 0; width: 650px; height: 288px; }
.reveal.l20-deck .l20-graph-arrows g { fill: none; stroke-width: 3; stroke-linecap: round; stroke-linejoin: round; }
.reveal.l20-deck .l20-graph-arrows .l20-gc-muted { stroke: #b7c3d8; }
.reveal.l20-deck .l20-graph-arrows .l20-gc-muted path { marker-end: url(#l20-gc-muted); }
.reveal.l20-deck .l20-graph-arrows .l20-gc-forward { stroke: #000f46; stroke-width: 4; }
.reveal.l20-deck .l20-graph-arrows .l20-gc-forward path { marker-end: url(#l20-gc-forward); }
.reveal.l20-deck .l20-graph-arrows .l20-gc-red { stroke: #ff4756; stroke-width: 4; }
.reveal.l20-deck .l20-graph-arrows .l20-gc-red path { marker-end: url(#l20-gc-red); }
.reveal.l20-deck .l20-graph-arrows .l20-gc-blue { stroke: #2563c9; stroke-width: 4; }
.reveal.l20-deck .l20-graph-arrows .l20-gc-blue path { marker-end: url(#l20-gc-blue); }
.reveal.l20-deck .l20-gc-node { position: absolute; z-index: 1; box-sizing: border-box; display: flex; gap: 6px; justify-content: center; align-items: center; height: 48px; border: 3px solid #000f46; border-radius: 11px; background: white; font-size: 25px; font-weight: 800; white-space: nowrap; }
.reveal.l20-deck .l20-gc-node mjx-container, .reveal.l20-deck .l20-pseudo-row mjx-container, .reveal.l20-deck .l20-pseudo-key mjx-container { margin: 0 !important; }
.reveal.l20-deck .l20-gc-x { left: 18px; top: 60px; width: 76px; }
.reveal.l20-deck .l20-gc-delta { left: 18px; top: 192px; width: 76px; border-color: #ff4756; color: #ff4756; }
.reveal.l20-deck .l20-gc-delta span[data-scene] { position: absolute; }
.reveal.l20-deck .l20-gc-plus { left: 124px; top: 125px; width: 47px; height: 47px; border-radius: 50%; }
.reveal.l20-deck .l20-gc-input { left: 204px; top: 127px; width: 96px; }
.reveal.l20-deck .l20-gc-model { left: 358px; top: 127px; width: 109px; background: #000f46; color: white; font-size: 22px; }
.reveal.l20-deck .l20-gc-loss { left: 542px; top: 127px; width: 88px; }
.reveal.l20-deck .l20-gc-weights { left: 358px; top: 22px; width: 109px; border-color: #2563c9; color: #2563c9; font-size: 18px; }
.reveal.l20-deck .l20-gc-label { left: 542px; top: 236px; width: 88px; font-size: 18px; }
.reveal.l20-deck .l20-graph-caption { position: relative; height: 44px; color: #000f46; font-size: 21px; font-weight: 700; text-align: center; }
.reveal.l20-deck .l20-graph-caption span[data-scene] { position: absolute; inset: 0; display: block; line-height: 44px; text-align: center; }
.reveal.l20-deck .l20-pseudo-panel { border-color: #2563c9; }
.reveal.l20-deck .l20-pseudo-panel h3 { margin: 0 0 8px; color: #2563c9; font-size: 23px; line-height: 36px; }
.reveal.l20-deck .l20-pseudo-list { padding: 4px 0; border-radius: 8px; background: #f3f3f6; }
.reveal.l20-deck .l20-pseudo-row { position: relative; display: flex; align-items: center; height: 40px; padding: 0 8px; font-size: 21px; white-space: nowrap; }
.reveal.l20-deck .l20-pseudo-row > span:not(.l20-pseudo-highlight) { position: relative; z-index: 1; }
.reveal.l20-deck .l20-pseudo-row small { font-family: inherit; font-size: 18px; color: #8290aa; }
.reveal.l20-deck .l20-pseudo-number { flex: 0 0 27px; color: #8290aa; font-size: 18px; font-weight: 700; }
.reveal.l20-deck .l20-pseudo-indent { padding-left: 24px; }
.reveal.l20-deck .l20-pseudo-highlight { position: absolute; inset: 0; border-left: 5px solid #000f46; border-radius: 5px; background: rgba(0, 15, 70, .10); }
.reveal.l20-deck .l20-pseudo-highlight-red { border-color: #ff4756; background: rgba(255, 71, 86, .12); }
.reveal.l20-deck .l20-pseudo-highlight-blue { border-color: #2563c9; background: rgba(37, 99, 201, .12); }
.reveal.l20-deck .l20-pseudo-key { margin-top: 12px; font-size: 18px; color: #333f6a; white-space: nowrap; }

/* Lecture 21: the same backdoor example before and after training. */
.reveal.l21-deck .l21-defence-problem .l21-problem-body { display: grid; width: 1400px; margin: auto 0; border-top: 2px solid var(--blue); }
.reveal.l21-deck .l21-defence-problem .l21-problem-row { display: grid; grid-template-columns: 370px minmax(0, 1fr); gap: 28px; align-items: center; box-sizing: border-box; min-height: 235px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.reveal.l21-deck .l21-defence-problem .l21-problem-heading { display: grid; grid-template-columns: 58px 1fr; column-gap: 18px; align-items: start; }
.reveal.l21-deck .l21-defence-problem .l21-problem-index { grid-row: span 2; color: var(--red); font-size: 25px; font-weight: 900; line-height: 1.2; }
.reveal.l21-deck .l21-defence-problem .l21-problem-heading h3 { margin: 0; color: var(--blue); font-size: 32px; line-height: 1.16; }
.reveal.l21-deck .l21-defence-problem .l21-problem-stage { grid-column: 2; margin-top: 9px; color: var(--ink-2); font-size: 23px; }
.reveal.l21-deck .l21-defence-problem .l21-problem-content { min-width: 0; }
.reveal.l21-deck .l21-defence-problem .l21-problem-action { display: block; margin: 0 0 14px; color: var(--ink); font-size: 33px; line-height: 1.2; }
.reveal.l21-deck .l21-defence-problem .l21-problem-detail { margin: 0; color: var(--ink-2); font-size: 27px; line-height: 1.33; }