/* ==========================================================================
   Signal deck engine — shared design system
   Semantic colour: every hue names a concept, so diagrams teach by colour.
   ========================================================================== */

:root {
  /* surfaces */
  --bg: #0b1030;
  --bg-2: #10173f;
  --surface: #151d4a;
  --surface-2: #1b2459;
  --line: rgba(173, 186, 255, 0.14);
  --line-2: rgba(173, 186, 255, 0.26);

  /* text */
  --ink: #eef0fb;
  --ink-2: #c3c9e8;
  --muted: #8d96c4;
  --faint: #59639a;

  /* semantic hues */
  --agent: #7fa8ff;     /* agents, retrievers, orchestration */
  --tool: #f6c350;      /* tools, functions, external calls */
  --state: #4fd6a8;     /* state, session, memory, index */
  --model: #ff8c74;     /* LLM / model calls */
  --human: #c8a2ff;     /* user, human-in-the-loop */
  --risk: #ff5f86;      /* failure, risk, anti-pattern */

  --agent-soft: rgba(127, 168, 255, 0.14);
  --tool-soft: rgba(246, 195, 80, 0.14);
  --state-soft: rgba(79, 214, 168, 0.14);
  --model-soft: rgba(255, 140, 116, 0.14);
  --human-soft: rgba(200, 162, 255, 0.15);
  --risk-soft: rgba(255, 95, 134, 0.14);

  --aurora: var(--agent);

  /* type */
  --f-display: "Geist", "Inter", system-ui, sans-serif;
  --f-body: "Geist", "Inter", system-ui, sans-serif;
  --f-mono: "JetBrains Mono", ui-monospace, "Cascadia Code", monospace;

  --r-s: 8px;
  --r-m: 14px;
  --r-l: 22px;
}

:root[data-theme="light"] {
  --bg: #ffffff;
  --bg-2: #ffffff;
  --surface: #f7f8fc;
  --surface-2: #ffffff;
  --line: rgba(22, 32, 90, 0.11);
  --line-2: rgba(22, 32, 90, 0.22);
  --ink: #0f1430;
  --ink-2: #333a5e;
  --muted: #646b8f;
  --faint: #a3a9c7;
  --agent: #2557e8;
  --tool: #c27c00;
  --state: #079669;
  --model: #e2502b;
  --human: #7b45dc;
  --risk: #d81f57;
  --agent-soft: rgba(37, 87, 232, 0.08);
  --tool-soft: rgba(194, 124, 0, 0.09);
  --state-soft: rgba(7, 150, 105, 0.08);
  --model-soft: rgba(226, 80, 43, 0.08);
  --human-soft: rgba(123, 69, 220, 0.08);
  --risk-soft: rgba(216, 31, 87, 0.08);
}
:root[data-theme="light"] .stage {
  background: #ffffff;
}
:root[data-theme="light"] .stage::before { display: none; }
:root[data-theme="light"] .stage::after { display: none; }
:root[data-theme="light"] .node { box-shadow: 0 1px 2px rgba(15, 20, 48, 0.06), 0 12px 32px -18px rgba(15, 20, 48, 0.28); }
:root[data-theme="light"] .panel { background: var(--surface); backdrop-filter: none; }
:root[data-theme="light"] .code-wrap { box-shadow: 0 24px 60px -30px rgba(15, 20, 48, 0.45); }
:root[data-theme="light"] .tag { background: #fff; }
:root[data-theme="light"] .cite { background: #fff; }

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--f-body);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }

/* ---------- stage + ambient background ---------- */

.stage {
  position: fixed;
  inset: 0;
  overflow: hidden;
  background:
    radial-gradient(1200px 700px at 85% -10%, color-mix(in oklab, var(--aurora) 22%, transparent), transparent 60%),
    radial-gradient(900px 600px at -10% 110%, color-mix(in oklab, var(--aurora) 12%, transparent), transparent 60%),
    linear-gradient(180deg, var(--bg), var(--bg-2));
  transition: background 1.2s ease;
}

.stage::before {
  /* faint engineering dot grid */
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(var(--line) 1px, transparent 1.2px);
  background-size: 32px 32px;
  mask-image: radial-gradient(ellipse at 60% 40%, #000 20%, transparent 75%);
  opacity: 0.7;
  pointer-events: none;
}

.stage::after {
  /* film grain */
  content: "";
  position: absolute;
  inset: -50%;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/></filter><rect width='100%' height='100%' filter='url(%23n)' opacity='.5'/></svg>");
  opacity: 0.05;
  pointer-events: none;
  mix-blend-mode: overlay;
}

.deck {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 1600px;
  height: 900px;
  transform-origin: 50% 50%;
}

/* ---------- slide ---------- */

.slide {
  position: absolute;
  inset: 0;
  padding: 84px 104px 76px;
  display: flex;
  flex-direction: column;
  gap: 28px;
  visibility: hidden;
  opacity: 0;
}
.slide.active { visibility: visible; opacity: 1; z-index: 2; }
.slide.leaving { visibility: visible; z-index: 1; }
.slide .notes { display: none; }

.slide.center { justify-content: center; }
.slide.tight { gap: 18px; }
.fill { flex: 1; min-height: 0; }

/* ---------- typography ---------- */

.display {
  font-family: var(--f-display);
  font-weight: 600;
  font-size: 104px;
  line-height: 1.0;
  letter-spacing: -0.045em;
  margin: 0;
}

.title {
  font-family: var(--f-display);
  font-weight: 600;
  font-size: 52px;
  line-height: 1.08;
  letter-spacing: -0.035em;
  margin: 0;
  max-width: 1300px;
  text-wrap: balance;
}
.title.sm { font-size: 48px; }

h3, .h3 {
  font-family: var(--f-display);
  font-weight: 600;
  font-size: 29px;
  line-height: 1.15;
  letter-spacing: -0.022em;
  margin: 0;
}
h4, .h4 {
  font-family: var(--f-body);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.2;
  margin: 0;
  color: var(--ink);
}

.lede {
  font-size: 28px;
  line-height: 1.4;
  color: var(--ink-2);
  max-width: 1120px;
  margin: 0;
  text-wrap: pretty;
}

p, li { font-size: 23px; line-height: 1.45; color: var(--ink-2); margin: 0; text-wrap: pretty; }
.small, .small p, .small li { font-size: 19px; line-height: 1.42; }
.tiny { font-size: 16px; line-height: 1.4; color: var(--muted); }
.muted { color: var(--muted); }
strong, b { color: var(--ink); font-weight: 650; }
em { font-style: normal; color: var(--ink); font-weight: 600; }

ul.clean, ol.clean { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
ul.ticks { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
ul.ticks > li { padding-left: 30px; position: relative; }
ul.ticks > li::before {
  content: ""; position: absolute; left: 4px; top: 0.58em; width: 12px; height: 12px;
  border-radius: 3px; background: var(--aurora); transform: rotate(45deg) scale(0.75);
}
ol.seq { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; counter-reset: s; }
ol.seq > li { counter-increment: s; padding-left: 52px; position: relative; }
ol.seq > li::before {
  content: counter(s); position: absolute; left: 0; top: -2px;
  width: 36px; height: 36px; border-radius: 50%;
  display: grid; place-items: center;
  font: 700 17px/1 var(--f-mono); color: var(--bg);
  background: var(--aurora);
}

code, .mono { font-family: var(--f-mono); font-size: 0.86em; }
:not(pre) > code {
  background: var(--surface-2);
  border: 1px solid var(--line);
  padding: 0.08em 0.38em;
  border-radius: 6px;
  color: var(--ink);
  white-space: nowrap;
}

/* semantic text */
.c-agent { color: var(--agent); } .c-tool { color: var(--tool); } .c-state { color: var(--state); }
.c-model { color: var(--model); } .c-human { color: var(--human); } .c-risk { color: var(--risk); }

/* ---------- layout ---------- */

.row { display: flex; gap: 28px; align-items: flex-start; }
.row.middle { align-items: center; }
.grid { display: grid; gap: 24px; }
.g2 { grid-template-columns: 1fr 1fr; }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g4 { grid-template-columns: repeat(4, 1fr); }
.g5 { grid-template-columns: repeat(5, 1fr); }
.g-12 { grid-template-columns: 1fr 2fr; }
.g-21 { grid-template-columns: 2fr 1fr; }
.g-32 { grid-template-columns: 3fr 2fr; }
.g-23 { grid-template-columns: 2fr 3fr; }
.stack { display: flex; flex-direction: column; gap: 16px; }
.stack.lg { gap: 26px; }
.push { margin-top: auto; }

/* ---------- surfaces ---------- */

.panel {
  background: color-mix(in oklab, var(--surface) 78%, transparent);
  border: 1px solid var(--line);
  border-radius: var(--r-l);
  padding: 26px 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  backdrop-filter: blur(6px);
}
.panel.flat { background: transparent; }
.panel.tight { padding: 18px 20px; gap: 8px; border-radius: var(--r-m); }
.panel.hot { border-color: var(--aurora); box-shadow: 0 0 0 1px var(--aurora), 0 18px 60px -20px color-mix(in oklab, var(--aurora) 60%, transparent); }

/* semantic accents on a panel: a coloured top rule + tinted surface */
.panel[class*="k-"] { border-top-width: 3px; }
.k-agent { border-top-color: var(--agent) !important; --aurora: var(--agent); }
.k-tool { border-top-color: var(--tool) !important; --aurora: var(--tool); }
.k-state { border-top-color: var(--state) !important; --aurora: var(--state); }
.k-model { border-top-color: var(--model) !important; --aurora: var(--model); }
.k-human { border-top-color: var(--human) !important; --aurora: var(--human); }
.k-risk { border-top-color: var(--risk) !important; --aurora: var(--risk); }

.tag {
  display: inline-flex; align-items: center; gap: 8px;
  font: 600 15px/1 var(--f-mono);
  padding: 7px 11px 7px 9px;
  border-radius: 999px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  color: var(--ink-2);
  white-space: nowrap;
}
.tag::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--aurora); }
.tag.t-agent { --aurora: var(--agent); } .tag.t-tool { --aurora: var(--tool); } .tag.t-state { --aurora: var(--state); }
.tag.t-model { --aurora: var(--model); } .tag.t-human { --aurora: var(--human); } .tag.t-risk { --aurora: var(--risk); }
.tag.new { background: color-mix(in oklab, var(--state) 18%, transparent); border-color: color-mix(in oklab, var(--state) 50%, transparent); color: var(--ink); --aurora: var(--state); }

.tags { display: flex; flex-wrap: wrap; gap: 10px; }

/* ---------- big numbers ---------- */

.stat { display: flex; flex-direction: column; gap: 6px; }
.stat .n {
  font-family: var(--f-display);
  font-weight: 600;
  font-size: 76px;
  line-height: 0.95;
  letter-spacing: -0.045em;
  color: var(--aurora);
}
.stat .l { font-size: 19px; color: var(--ink-2); line-height: 1.35; }

/* ---------- quote + citations ---------- */

.quote {
  font-family: var(--f-display);
  font-size: 34px; line-height: 1.25; font-weight: 500;
  letter-spacing: -0.025em;
  color: var(--ink);
  margin: 0;
  padding-left: 28px;
  border-left: 4px solid var(--aurora);
  text-wrap: balance;
}

.cite {
  display: inline-flex; align-items: center; gap: 10px;
  font: 500 16px/1.3 var(--f-body);
  color: var(--muted);
  text-decoration: none;
  padding: 8px 14px 8px 10px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: color-mix(in oklab, var(--surface) 60%, transparent);
  max-width: 100%;
  transition: border-color .2s, color .2s;
}
.cite:hover { border-color: var(--line-2); color: var(--ink); }
.cite b { color: var(--ink-2); font-weight: 600; }
.cite::before {
  content: ""; flex: none; width: 22px; height: 22px; border-radius: 6px;
  background: var(--src-c, var(--agent));
  -webkit-mask: var(--src-i) center/16px no-repeat, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude;
}
.cite.codelab { --src-c: var(--state); --src-i: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M8 6l-6 6 6 6M16 6l6 6-6 6' fill='none' stroke='black' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/></svg>"); }
.cite.repo { --src-c: var(--ink-2); --src-i: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><circle cx='6' cy='5' r='2.5' fill='black'/><circle cx='6' cy='19' r='2.5' fill='black'/><circle cx='18' cy='8' r='2.5' fill='black'/><path d='M6 7v10M18 10c0 4-6 4-11 7' fill='none' stroke='black' stroke-width='2.4'/></svg>"); }
.cite.doc { --src-c: var(--agent); --src-i: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M6 3h8l4 4v14H6z' fill='black'/></svg>"); }
.cite.video { --src-c: var(--model); --src-i: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M8 5l11 7-11 7z' fill='black'/></svg>"); }
.cite.paper { --src-c: var(--human); --src-i: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M4 4h16v4H4zM4 10h16v2H4zM4 14h11v2H4zM4 18h13v2H4z' fill='black'/></svg>"); }
.cites { display: flex; flex-wrap: wrap; gap: 10px; }

/* ---------- code ---------- */

.code-wrap {
  align-self: start;
  position: relative;
  border-radius: var(--r-m);
  background: #070b22;
  border: 1px solid var(--line);
  overflow: hidden;
  box-shadow: 0 30px 80px -40px rgba(0, 0, 0, 0.8);
}
:root[data-theme="light"] .code-wrap { background: #0f1433; }
.code-wrap .code-head {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 16px;
  border-bottom: 1px solid rgba(173, 186, 255, 0.12);
  font: 500 15px/1 var(--f-mono);
  color: #8d96c4;
}
.code-wrap .code-head::before {
  content: ""; width: 10px; height: 10px; border-radius: 50%;
  background: var(--aurora);
  box-shadow: 0 0 12px var(--aurora);
}
pre.code {
  font-variant-ligatures: none;
  margin: 0;
  padding: 18px 22px 20px;
  font: 400 18px/1.55 var(--f-mono);
  color: #dfe3fb;
  white-space: pre;
  overflow: hidden;
  position: relative;
  z-index: 1;
  tab-size: 4;
}
pre.code.sm { font-size: 16px; }
pre.code.xs { font-size: 14.5px; }
pre.code code { font: inherit; background: none; border: 0; padding: 0; white-space: pre; color: inherit; }
.code-wrap .band {
  position: absolute; left: 0; right: 0; z-index: 0;
  background: color-mix(in oklab, var(--aurora) 16%, transparent);
  border-left: 3px solid var(--aurora);
  opacity: 0;
  pointer-events: none;
}
.code-wrap.focusing pre.code { color: #8d96c4; }

/* prism tokens, tuned to the semantic palette */
.token.comment, .token.prolog { color: #6670a6; font-style: italic; }
.token.keyword, .token.boolean, .token.important { color: #c8a2ff; }
.token.string, .token.triple-quoted-string, .token.char { color: #8fe3bf; }
.token.function, .token.class-name { color: #7fb0ff; }
.token.number, .token.constant { color: #ffb38a; }
.token.decorator, .token.annotation, .token.builtin { color: #f6c350; }
.token.operator, .token.punctuation { color: #9aa3cf; }
.token.property, .token.attr-name { color: #7fd6ff; }
.token.parameter { color: #e8ebff; }

/* terminal */
.term { background: #050818; }
.term pre.code { color: #cfd5f5; }
.term .prompt { color: var(--state); user-select: none; }
.term .out { color: #8d96c4; }

/* ---------- diagram system ---------- */

.diagram { position: relative; flex: none; }
.diagram > svg.wires {
  position: absolute; inset: 0; width: 100%; height: 100%;
  overflow: visible; pointer-events: none; z-index: 0;
}
.wires path.w { fill: none; stroke: var(--line-2); stroke-width: 2.2; stroke-linecap: round; }
.wires path.w.dash { stroke-dasharray: 7 8; }
.wires path.w.hot { stroke: var(--wc, var(--agent)); stroke-width: 2.8; }
.wires .arrow { fill: var(--line-2); }
.wires .arrow.hot { fill: var(--wc, var(--agent)); }
.wires .pulse { fill: var(--wc, var(--agent)); filter: drop-shadow(0 0 6px var(--wc, var(--agent))); }
.wires text.wl {
  font: 600 14px/1 var(--f-mono); fill: var(--muted);
  paint-order: stroke; stroke: var(--bg); stroke-width: 6px; stroke-linejoin: round;
}

.node {
  position: absolute;
  z-index: 1;
  min-width: 120px;
  padding: 14px 18px;
  border-radius: var(--r-m);
  background: color-mix(in oklab, var(--surface-2) 92%, transparent);
  border: 1.5px solid var(--nc, var(--line-2));
  color: var(--ink);
  display: flex; flex-direction: column; gap: 4px;
  box-shadow: 0 14px 40px -24px rgba(0, 0, 0, 0.9);
  transition: box-shadow .45s, transform .45s, border-color .45s, background .45s;
}
.node .nt { font: 700 19px/1.15 var(--f-body); }
.node .ns { font: 500 15px/1.3 var(--f-mono); color: var(--muted); }
.node.pill { border-radius: 999px; padding: 12px 22px; align-items: center; }
.node.round { border-radius: 50%; width: 120px; height: 120px; min-width: 0; align-items: center; justify-content: center; text-align: center; }
.node.ghost { background: transparent; border-style: dashed; }
.node.n-agent { --nc: var(--agent); background: linear-gradient(180deg, var(--agent-soft), transparent 140%), var(--surface-2); }
.node.n-tool { --nc: var(--tool); background: linear-gradient(180deg, var(--tool-soft), transparent 140%), var(--surface-2); }
.node.n-state { --nc: var(--state); background: linear-gradient(180deg, var(--state-soft), transparent 140%), var(--surface-2); }
.node.n-model { --nc: var(--model); background: linear-gradient(180deg, var(--model-soft), transparent 140%), var(--surface-2); }
.node.n-human { --nc: var(--human); background: linear-gradient(180deg, var(--human-soft), transparent 140%), var(--surface-2); }
.node.n-risk { --nc: var(--risk); background: linear-gradient(180deg, var(--risk-soft), transparent 140%), var(--surface-2); }
.node.hot, .node.lit {
  box-shadow: 0 0 0 4px color-mix(in oklab, var(--nc, var(--agent)) 30%, transparent), 0 20px 60px -18px var(--nc, var(--agent));
  transform: translateY(-3px);
}
.node.dim, .dim { opacity: 0.32; }

.group {
  position: absolute; z-index: 0;
  border: 1.5px dashed var(--gc, var(--line-2));
  border-radius: var(--r-l);
  background: color-mix(in oklab, var(--gc, var(--line)) 7%, transparent);
}
.group > .gl {
  position: absolute; top: -13px; left: 18px;
  font: 600 15px/1 var(--f-mono);
  color: var(--gc, var(--muted));
  background: var(--bg);
  padding: 4px 10px; border-radius: 6px;
}
.group.g-agent { --gc: var(--agent); } .group.g-tool { --gc: var(--tool); } .group.g-state { --gc: var(--state); }
.group.g-model { --gc: var(--model); } .group.g-human { --gc: var(--human); } .group.g-risk { --gc: var(--risk); }

/* legend of the semantic palette */
.legend { display: flex; gap: 18px; flex-wrap: wrap; }
.legend span { display: inline-flex; align-items: center; gap: 8px; font: 500 15px/1 var(--f-mono); color: var(--muted); }
.legend span::before { content: ""; width: 12px; height: 12px; border-radius: 4px; background: var(--lc); }
.legend .l-agent { --lc: var(--agent); } .legend .l-tool { --lc: var(--tool); } .legend .l-state { --lc: var(--state); }
.legend .l-model { --lc: var(--model); } .legend .l-human { --lc: var(--human); } .legend .l-risk { --lc: var(--risk); }

/* ---------- tables ---------- */

table.t {
  width: 100%; border-collapse: collapse;
  font-size: 19px; line-height: 1.35;
}
table.t th {
  text-align: left; font: 600 16px/1.2 var(--f-mono); color: var(--muted);
  padding: 10px 14px; border-bottom: 1px solid var(--line-2);
}
table.t td { padding: 12px 14px; border-bottom: 1px solid var(--line); color: var(--ink-2); vertical-align: top; }
table.t td:first-child { color: var(--ink); font-weight: 600; }
table.t tr.hot td { background: color-mix(in oklab, var(--aurora) 12%, transparent); }

/* ---------- chapter (section opener) ---------- */

.slide.chapter { justify-content: flex-end; padding-bottom: 110px; }
.slide.chapter .ch-num {
  font-family: var(--f-display);
  font-weight: 700;
  font-size: 360px;
  line-height: 0.8;
  letter-spacing: -0.06em;
  position: absolute;
  right: 80px; top: 40px;
  color: color-mix(in oklab, var(--aurora) 12%, transparent);
  pointer-events: none;
}
.slide.chapter .display { max-width: 1200px; }
.slide.chapter .lede { max-width: 900px; }

/* ---------- interview lens ---------- */

.qa { display: grid; gap: 14px; }
.qa .q {
  display: flex; gap: 14px; align-items: baseline;
  font: 600 24px/1.3 var(--f-display); letter-spacing: -0.015em; color: var(--ink);
}
.qa .q::before {
  content: "Q"; flex: none;
  font: 700 15px/1 var(--f-mono); color: #fff; background: var(--human);
  width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center;
  transform: translateY(2px);
}
.qa .a {
  margin-left: 42px; padding: 14px 18px;
  border-left: 3px solid var(--state);
  background: var(--state-soft);
  border-radius: 0 12px 12px 0;
  font-size: 19px; line-height: 1.45; color: var(--ink-2);
}
.qa .a b { color: var(--ink); }

/* failure mode / pitfall + key insight callouts */
.callout {
  display: flex; gap: 14px; align-items: flex-start;
  padding: 16px 20px; border-radius: 14px;
  border: 1px solid color-mix(in oklab, var(--cc, var(--agent)) 35%, transparent);
  background: color-mix(in oklab, var(--cc, var(--agent)) 7%, transparent);
  font-size: 19px; line-height: 1.45; color: var(--ink-2);
}
.callout::before {
  flex: none; content: "i"; width: 26px; height: 26px; border-radius: 50%;
  display: grid; place-items: center; margin-top: 1px;
  font: 700 15px/1 var(--f-mono); color: #fff; background: var(--cc, var(--agent));
}
.callout.pitfall { --cc: var(--risk); }
.callout.pitfall::before { content: "!"; }
.callout.insight { --cc: var(--state); }
.callout.insight::before { content: "✓"; }
.callout.tip { --cc: var(--tool); }
.callout.tip::before { content: "→"; }

/* ---------- misc ---------- */

.divider { height: 1px; background: var(--line); width: 100%; }
.kbd { font: 600 15px/1 var(--f-mono); padding: 5px 8px; border-radius: 6px; border: 1px solid var(--line-2); border-bottom-width: 3px; }
.badge-new {
  display: inline-block; font: 700 13px/1 var(--f-mono);
  padding: 5px 8px; border-radius: 6px; vertical-align: middle;
  color: var(--bg); background: var(--state); margin-left: 8px;
  transform: translateY(-3px);
}
.bar { height: 14px; border-radius: 999px; background: var(--surface-2); overflow: hidden; }
.bar > i { display: block; height: 100%; width: var(--v, 50%); background: var(--aurora); border-radius: inherit; transform-origin: left; }

.vs { display: grid; grid-template-columns: 1fr auto 1fr; gap: 28px; align-items: stretch; }
.vs > .mid { align-self: center; font: 800 28px/1 var(--f-display); color: var(--faint); }

/* interactive bits authored per slide */
.interactive { cursor: default; }
button.ctl, .ctl {
  font: 600 17px/1 var(--f-body);
  color: var(--ink);
  background: var(--surface-2);
  border: 1px solid var(--line-2);
  border-radius: 10px;
  padding: 11px 16px;
  cursor: pointer;
}
button.ctl:hover { border-color: var(--aurora); }
button.ctl:focus-visible, a:focus-visible { outline: 3px solid var(--aurora); outline-offset: 3px; }
input[type="range"] { accent-color: var(--aurora); width: 100%; }

/* ---------- chrome: outline drawer, notes, hint ---------- */

.chrome-progress {
  position: fixed; left: 0; top: 0; height: 2px; width: 100%;
  transform-origin: left; transform: scaleX(0);
  background: var(--aurora);
  opacity: 0; transition: opacity .4s, transform .5s cubic-bezier(.2,.8,.2,1);
  z-index: 20;
}
body.mouse-active .chrome-progress { opacity: 0.8; }

.outline {
  position: fixed; top: 0; right: 0; bottom: 0; width: min(460px, 92vw);
  background: color-mix(in oklab, var(--bg) 92%, transparent);
  backdrop-filter: blur(18px);
  border-left: 1px solid var(--line);
  transform: translateX(105%);
  transition: transform .45s cubic-bezier(.2,.8,.2,1);
  z-index: 30; overflow-y: auto; padding: 28px 22px;
}
.outline.open { transform: none; }
.outline h5 { font: 700 13px/1 var(--f-mono); color: var(--muted); margin: 22px 8px 10px; letter-spacing: 0.04em; }
.outline button {
  display: block; width: 100%; text-align: left;
  background: none; border: 0; color: var(--ink-2);
  font: 500 15.5px/1.35 var(--f-body);
  padding: 8px 10px; border-radius: 8px; cursor: pointer;
}
.outline button:hover { background: var(--surface); color: var(--ink); }
.outline button.cur { background: var(--surface-2); color: var(--ink); box-shadow: inset 3px 0 0 var(--aurora); }

.notes-pane {
  position: fixed; left: 24px; bottom: 24px; width: min(620px, 90vw); max-height: 40vh; overflow: auto;
  background: color-mix(in oklab, var(--bg) 94%, transparent);
  border: 1px solid var(--line-2); border-radius: 14px;
  padding: 18px 20px; z-index: 25;
  font: 400 16px/1.5 var(--f-body); color: var(--ink-2);
  display: none;
}
.notes-pane.open { display: block; }

.hint {
  position: fixed; right: 20px; bottom: 16px; z-index: 20;
  font: 500 13px/1 var(--f-mono); color: var(--faint);
  opacity: 0; transition: opacity .4s;
}
body.mouse-active .hint { opacity: 1; }

/* ---------- print: one page per slide, all steps visible ---------- */
@media print {
  @page { size: 1600px 900px; margin: 0; }
  html, body { overflow: visible; height: auto; background: var(--bg); }
  .stage { position: static; }
  .deck { position: static; transform: none !important; }
  .slide { position: relative; visibility: visible !important; opacity: 1 !important; page-break-after: always; height: 900px; width: 1600px; }
  .slide [data-step], .slide * { opacity: 1 !important; visibility: visible !important; transform: none !important; filter: none !important; }
  .chrome-progress, .outline, .notes-pane, .hint { display: none !important; }
  -webkit-print-color-adjust: exact; print-color-adjust: exact;
}

@media (prefers-reduced-motion: reduce) {
  .stage { transition: none; }
}