/* ============================================================
   Business Debt Adjusters — The Business Debt Settlement Playbook
   Interactive e-book
   ============================================================ */

:root {
  /* brand */
  --navy:        #0a1f55;
  --navy-deep:   #061338;
  --bda-blue:    #00b0f0;
  --bda-blue-2:  #1ec0ff;
  --ink:         #0a0f1f;
  --ink-2:       #2a2f40;
  --muted:       #6b7081;
  --paper:       #f7f5f0;
  --paper-2:     #efece4;
  --line:        #d9d5c8;
  --line-2:      #e7e3d6;
  --white:       #ffffff;
  --rust:        oklch(0.6 0.18 30);
  --rust-tint:   oklch(0.94 0.04 30);
  --amber:       oklch(0.78 0.14 78);
  --amber-tint:  oklch(0.96 0.05 78);
  --green:       oklch(0.55 0.12 155);
  --green-tint:  oklch(0.94 0.04 155);

  /* layout */
  --maxw: 760px;
  --sidew: 300px;

  /* type */
  --f-serif: "Source Serif 4", "Source Serif Pro", Georgia, serif;
  --f-sans:  "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --f-mono:  "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
/* Scoped to #root so the ebook styles don't bleed into the site nav/footer. */
#root {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--f-sans);
  font-size: 17px;
  line-height: 1.6;
  font-feature-settings: "ss01", "cv11";
  -webkit-font-smoothing: antialiased;
}
#root img { max-width: 100%; display: block; }
#root a {
  color: var(--navy);
  text-decoration: underline;
  text-decoration-color: color-mix(in oklab, var(--navy) 30%, transparent);
  text-underline-offset: 3px;
}
#root a:hover { text-decoration-color: var(--bda-blue); }

/* --- diamond grid watermark from logo --- */
.diamond-grid-bg {
  background-image:
    linear-gradient(135deg, transparent 46%, color-mix(in oklab, var(--navy) 6%, transparent) 47%, color-mix(in oklab, var(--navy) 6%, transparent) 53%, transparent 54%),
    linear-gradient(45deg,  transparent 46%, color-mix(in oklab, var(--navy) 6%, transparent) 47%, color-mix(in oklab, var(--navy) 6%, transparent) 53%, transparent 54%);
  background-size: 28px 28px;
}

/* ===================== HERO / COVER ===================== */
.hero {
  background: var(--navy-deep);
  background-image:
    radial-gradient(ellipse at 80% 0%, color-mix(in oklab, var(--bda-blue) 30%, transparent) 0%, transparent 55%),
    radial-gradient(ellipse at 0% 100%, color-mix(in oklab, var(--navy) 60%, transparent) 0%, transparent 50%);
  color: var(--white);
  padding: 28px 0 0;
  position: relative;
  overflow: hidden;
}
.hero-bar {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 1240px; margin: 0 auto; padding: 0 32px;
}
.hero-bar img { width: 220px; height: auto; }
.hero-bar .crumb {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.18em;
  color: color-mix(in oklab, white 70%, transparent); text-transform: uppercase;
}
.hero-grid {
  max-width: 1240px; margin: 0 auto; padding: 80px 32px 100px;
  display: grid; grid-template-columns: 1.2fr 1fr; gap: 80px; align-items: end;
}
.hero h1 {
  font-family: var(--f-serif);
  font-weight: 500;
  font-size: clamp(40px, 5.4vw, 76px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin: 0 0 60px;
  text-wrap: balance;
  padding-bottom: 14px;
}
.hero h1 em {
  font-style: italic;
  color: var(--bda-blue);
  font-weight: 400;
}
.hero .deck {
  font-size: 18px;
  line-height: 1.55;
  color: color-mix(in oklab, white 78%, transparent);
  max-width: 540px;
  margin-bottom: 28px;
}
.hero .meta {
  font-family: var(--f-mono); font-size: 12px; letter-spacing: 0.12em;
  text-transform: uppercase;
  color: color-mix(in oklab, white 60%, transparent);
  display: flex; gap: 24px; flex-wrap: wrap;
}
.hero .meta span::before {
  content: "◆"; color: var(--bda-blue); margin-right: 8px; font-size: 9px; position: relative; top: -2px;
}

.hero-card {
  background: color-mix(in oklab, white 6%, transparent);
  border: 1px solid color-mix(in oklab, white 14%, transparent);
  backdrop-filter: blur(6px);
  border-radius: 4px;
  padding: 28px;
}
.hero-card h3 {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--bda-blue);
  margin: 0 0 18px;
}
.hero-card .toc-row {
  display: grid; grid-template-columns: 28px 1fr auto; gap: 14px; padding: 8px 0;
  border-bottom: 1px dashed color-mix(in oklab, white 15%, transparent);
  font-size: 14px; color: color-mix(in oklab, white 85%, transparent);
  cursor: pointer;
  transition: color .15s;
}
.hero-card .toc-row:hover { color: var(--bda-blue); }
.hero-card .toc-row .num {
  font-family: var(--f-mono); font-size: 11px;
  color: color-mix(in oklab, white 50%, transparent);
}
.hero-card .toc-row .dur {
  font-family: var(--f-mono); font-size: 11px;
  color: color-mix(in oklab, white 50%, transparent);
}

.hero-cta {
  display: inline-flex; align-items: center; gap: 12px;
  background: var(--bda-blue); color: var(--navy-deep);
  padding: 14px 22px; border-radius: 2px;
  font-weight: 600; font-size: 14px;
  text-decoration: none; letter-spacing: 0.02em;
  border: none; cursor: pointer;
  transition: transform .15s, background .15s;
  white-space: nowrap;
}
.hero-cta:hover { background: var(--bda-blue-2); transform: translateY(-1px); }
.hero-cta.ghost {
  background: transparent; color: #ffffff !important;
  border: 1.5px solid rgba(255,255,255,0.6) !important;
}
.hero-cta.ghost:hover { background: rgba(255,255,255,0.12) !important; border-color: #ffffff !important; }
.cta-row { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 6px; }

/* hero diamond pattern bottom */
.hero-pattern {
  position: absolute; right: -40px; bottom: -40px; opacity: 0.08;
  width: 320px; height: 320px; pointer-events: none;
}

/* ============= warning strip ============= */
.disclaimer-strip {
  background: var(--ink);
  color: color-mix(in oklab, white 80%, transparent);
  font-family: var(--f-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  padding: 14px 32px;
  text-align: center;
  border-top: 1px solid color-mix(in oklab, white 6%, transparent);
}
.disclaimer-strip b { color: var(--bda-blue); }

/* ===================== READER LAYOUT ===================== */
.reader {
  display: grid;
  grid-template-columns: var(--sidew) minmax(0, 1fr);
  max-width: 1240px;
  margin: 0 auto;
  gap: 56px;
  padding: 60px 32px 80px;
}

aside.toc {
  position: sticky;
  top: 24px;
  align-self: start;
  max-height: calc(100vh - 48px);
  overflow-y: auto;
  padding-right: 12px;
  font-size: 14px;
}
aside.toc::-webkit-scrollbar { width: 4px; }
aside.toc::-webkit-scrollbar-thumb { background: var(--line); border-radius: 2px; }

.toc-label {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--muted);
  margin: 0 0 14px;
}
.toc-progress {
  height: 4px; background: var(--line-2); border-radius: 4px; overflow: hidden;
  margin-bottom: 8px;
}
.toc-progress > div {
  height: 100%; background: var(--bda-blue); transition: width .25s;
}
.toc-prog-text {
  display: flex; justify-content: space-between;
  font-family: var(--f-mono); font-size: 10.5px;
  color: var(--muted); margin-bottom: 24px;
}

.complexity {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 14px 14px 16px;
  margin-bottom: 24px;
  border-radius: 2px;
}
.complexity .lbl {
  font-family: var(--f-mono); font-size: 10.5px; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--muted);
  display: flex; justify-content: space-between;
  margin-bottom: 8px;
}
.complexity .lbl b { color: var(--rust); }
.complexity .bar {
  display: grid; grid-template-columns: repeat(10, 1fr); gap: 3px;
  margin-bottom: 8px;
}
.complexity .bar > div {
  height: 16px; background: var(--line-2); border-radius: 1px;
  transition: background .25s;
}
.complexity .bar > div.filled { background: var(--rust); }
.complexity .bar > div.filled.mid { background: var(--amber); }
.complexity .desc {
  font-size: 12px; color: var(--ink-2); line-height: 1.45;
  font-style: italic;
}

.toc-list { list-style: none; margin: 0; padding: 0; }
.toc-list li {
  display: grid; grid-template-columns: 26px 1fr;
  gap: 10px; padding: 7px 0;
  cursor: pointer;
  border-left: 2px solid transparent;
  padding-left: 10px;
  margin-left: -12px;
  color: var(--ink-2);
  transition: color .12s, border-color .12s;
}
.toc-list li:hover { color: var(--navy); }
.toc-list li.active {
  color: var(--navy);
  border-left-color: var(--bda-blue);
  font-weight: 600;
}
.toc-list .num {
  font-family: var(--f-mono); font-size: 11px; color: var(--muted);
  padding-top: 2px;
}
.toc-list li.active .num { color: var(--bda-blue); }

/* === content column === */
main.content {
  max-width: var(--maxw);
  width: 100%;
}

.chapter {
  margin-bottom: 96px;
  scroll-margin-top: 24px;
}
.chapter-eyebrow {
  font-family: var(--f-mono); font-size: 11.5px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--bda-blue);
  display: flex; align-items: center; gap: 12px;
  margin-bottom: 14px;
}
.chapter-eyebrow::after {
  content: ""; flex: 1; height: 1px;
  background: linear-gradient(to right, var(--line) 0%, transparent 100%);
}
.chapter h2 {
  font-family: var(--f-serif);
  font-size: clamp(32px, 4vw, 46px);
  line-height: 1.05;
  letter-spacing: -0.015em;
  font-weight: 500;
  margin: 0 0 18px;
  color: var(--navy);
  text-wrap: balance;
}
.chapter h2 em { font-style: italic; color: var(--ink); font-weight: 400; }

.chapter .lede {
  font-size: 19px;
  line-height: 1.5;
  color: var(--ink-2);
  border-left: 3px solid var(--bda-blue);
  padding-left: 18px;
  margin: 0 0 32px;
  font-family: var(--f-serif);
  font-style: italic;
  font-weight: 400;
}

.chapter p { margin: 0 0 18px; text-wrap: pretty; }
.chapter h3 {
  font-family: var(--f-sans);
  font-weight: 600;
  font-size: 18px;
  margin: 32px 0 12px;
  letter-spacing: -0.005em;
}
.chapter h4 {
  font-family: var(--f-mono);
  font-weight: 500;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 28px 0 10px;
}
.chapter ul, .chapter ol { padding-left: 22px; margin: 0 0 18px; }
.chapter li { margin: 4px 0; }
.chapter li::marker { color: var(--bda-blue); }

/* footnote refs */
sup.fn {
  display: inline-block;
  background: var(--bda-blue);
  color: var(--navy-deep);
  font-family: var(--f-mono);
  font-size: 9.5px;
  padding: 1px 5px;
  border-radius: 2px;
  margin: 0 2px;
  cursor: pointer;
  font-weight: 600;
  text-decoration: none;
  vertical-align: super;
  line-height: 1;
}
sup.fn a { color: inherit; text-decoration: none; }
sup.fn:hover { background: var(--bda-blue-2); }

/* ============== placeholder imagery ============== */
.placeholder {
  background: repeating-linear-gradient(
    -45deg,
    var(--paper-2) 0 12px,
    color-mix(in oklab, var(--paper-2) 60%, var(--white)) 12px 24px
  );
  border: 1px dashed var(--line);
  border-radius: 2px;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex; align-items: center; justify-content: center;
  text-align: center;
  padding: 16px;
}
.placeholder .ph-inner { background: var(--paper); padding: 6px 10px; border: 1px solid var(--line); }

/* ============== widget shells ============== */
.widget {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 3px;
  margin: 26px 0;
  overflow: hidden;
}
.widget-head {
  padding: 14px 18px;
  background: var(--paper-2);
  border-bottom: 1px solid var(--line);
  display: flex; align-items: center; justify-content: space-between;
}
.widget-head .title {
  font-family: var(--f-mono);
  font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--navy);
  font-weight: 600;
}
.widget-head .tag {
  font-family: var(--f-mono);
  font-size: 10px; letter-spacing: 0.12em;
  color: var(--muted);
  display: flex; align-items: center; gap: 6px;
}
.widget-head .tag .dot {
  width: 6px; height: 6px; background: var(--bda-blue); border-radius: 50%;
  animation: pulse 1.6s ease-in-out infinite;
}
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: .3; } }
.widget-body { padding: 18px; }

/* ============== matrix table ============== */
table.matrix {
  width: 100%; border-collapse: collapse;
  font-size: 13px; font-family: var(--f-sans);
}
table.matrix thead th {
  text-align: left; padding: 10px 12px;
  font-family: var(--f-mono); font-size: 10.5px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--muted);
  border-bottom: 1px solid var(--line);
  font-weight: 500;
  background: var(--paper);
}
table.matrix td {
  padding: 12px;
  border-bottom: 1px solid var(--line-2);
  vertical-align: top;
}
table.matrix tr { transition: background .12s; }
table.matrix tr:hover { background: color-mix(in oklab, var(--bda-blue) 5%, transparent); }
table.matrix tr.expanded { background: color-mix(in oklab, var(--bda-blue) 7%, transparent); }
table.matrix tr.detail td {
  background: var(--paper);
  padding: 14px 18px;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  color: var(--ink-2);
}
table.matrix .pill {
  display: inline-block; padding: 2px 8px;
  border-radius: 2px;
  font-family: var(--f-mono); font-size: 10.5px; letter-spacing: 0.06em;
  font-weight: 500;
}
.pill.r { background: var(--rust-tint); color: var(--rust); }
.pill.a { background: var(--amber-tint); color: color-mix(in oklab, var(--amber) 80%, black); }
.pill.g { background: var(--green-tint); color: color-mix(in oklab, var(--green) 80%, black); }
.pill.n { background: var(--paper-2); color: var(--muted); }

/* ============== flow diagram ============== */
.flow {
  display: flex; flex-direction: column; align-items: center;
  gap: 0; padding: 8px 0;
}
.flow .node {
  background: var(--white);
  border: 1.5px solid var(--navy);
  border-radius: 2px;
  padding: 11px 18px;
  min-width: 220px;
  text-align: center;
  font-family: var(--f-sans);
  font-size: 14px;
  font-weight: 500;
  color: var(--navy);
  position: relative;
  transition: transform .2s, background .2s, color .2s;
}
.flow .node.active {
  background: var(--navy);
  color: var(--white);
  transform: scale(1.04);
}
.flow .node.dim { opacity: 0.35; }
.flow .arrow {
  height: 28px; width: 2px;
  background: var(--navy);
  position: relative;
}
.flow .arrow::after {
  content: ""; position: absolute; bottom: 0; left: 50%; transform: translateX(-50%);
  border-left: 5px solid transparent; border-right: 5px solid transparent;
  border-top: 7px solid var(--navy);
}
.flow-controls {
  display: flex; justify-content: center; gap: 8px; margin-top: 16px;
}
.flow-controls button {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.1em;
  text-transform: uppercase; padding: 7px 14px;
  background: var(--white); border: 1px solid var(--line);
  color: var(--ink-2); cursor: pointer; border-radius: 2px;
  transition: all .12s;
}
.flow-controls button:hover { border-color: var(--navy); color: var(--navy); }
.flow-controls button.primary { background: var(--navy); color: var(--white); border-color: var(--navy); }
.flow-controls button.primary:hover { background: var(--bda-blue); border-color: var(--bda-blue); color: var(--navy-deep); }

/* ============== if/then tile ============== */
.iflist { display: grid; gap: 10px; }
.iftile {
  display: grid;
  grid-template-columns: 1fr 22px 1fr;
  gap: 14px; align-items: center;
  padding: 14px 16px;
  background: var(--paper);
  border: 1px solid var(--line-2);
  border-left: 3px solid var(--bda-blue);
  border-radius: 2px;
  font-size: 14px;
  transition: background .15s, border-color .15s;
  cursor: default;
}
.iftile:hover { background: var(--white); border-left-color: var(--rust); }
.iftile .if { color: var(--ink-2); }
.iftile .if::before {
  content: "IF"; font-family: var(--f-mono); font-size: 10px; letter-spacing: 0.16em;
  display: block; color: var(--muted); margin-bottom: 4px;
}
.iftile .arrow { color: var(--bda-blue); font-family: var(--f-mono); text-align: center; }
.iftile .then { color: var(--navy); font-weight: 500; }
.iftile .then::before {
  content: "THEN"; font-family: var(--f-mono); font-size: 10px; letter-spacing: 0.16em;
  display: block; color: var(--muted); margin-bottom: 4px; font-weight: 400;
}

/* ============== dependency web ============== */
.depweb-wrap {
  position: relative;
  padding: 12px 0;
}
.depweb-svg { display: block; width: 100%; height: auto; }
.depweb-legend {
  font-family: var(--f-mono); font-size: 10.5px;
  color: var(--muted); letter-spacing: 0.08em;
  text-align: center; margin-top: 10px;
}
.depweb-node-label { font-size: 11px; font-family: var(--f-sans); font-weight: 500; }

/* ============== calculator ============== */
.calc { display: grid; gap: 12px; }
.calc-row {
  display: grid;
  grid-template-columns: 1fr 140px;
  gap: 14px; align-items: center;
  padding: 8px 0;
  border-bottom: 1px dashed var(--line-2);
}
.calc-row label {
  font-size: 13px; color: var(--ink-2);
}
.calc-row .sublabel {
  display: block; font-family: var(--f-mono); font-size: 10px;
  color: var(--muted); letter-spacing: 0.08em; text-transform: uppercase;
  margin-top: 2px;
}
.calc-row input[type=number], .calc-row input[type=text] {
  width: 100%; font-family: var(--f-mono); font-size: 14px;
  padding: 8px 10px; border: 1px solid var(--line); border-radius: 2px;
  text-align: right; background: var(--paper);
  color: var(--ink);
}
.calc-row input:focus { outline: none; border-color: var(--bda-blue); background: var(--white); }
.calc-out {
  background: var(--navy);
  color: var(--white);
  margin-top: 8px;
  padding: 14px 16px;
  border-radius: 2px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  align-items: end;
}
.calc-out .lbl {
  font-family: var(--f-mono); font-size: 10.5px;
  letter-spacing: 0.14em; text-transform: uppercase;
  color: color-mix(in oklab, white 70%, transparent);
}
.calc-out .val {
  font-family: var(--f-mono); font-size: 26px;
  color: var(--bda-blue); font-weight: 500;
}
.calc-warn {
  margin-top: 10px;
  font-size: 12.5px;
  color: var(--rust);
  display: flex; gap: 8px; align-items: flex-start;
}
.calc-warn .ic {
  font-family: var(--f-mono); font-weight: 700; font-size: 11px;
  background: var(--rust-tint); padding: 2px 5px; border-radius: 2px;
}

/* ============== animated presenter widget ============== */
.presenter {
  background: var(--navy-deep);
  border-radius: 3px;
  overflow: hidden;
  position: relative;
  aspect-ratio: 16/9;
}
.presenter svg { display: block; width: 100%; height: 100%; }
.presenter .scrim {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: 12px 14px;
  background: linear-gradient(to top, rgba(0,0,0,0.6), transparent);
  color: white;
  display: flex; align-items: center; justify-content: space-between;
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.12em;
}
.presenter .play {
  background: var(--bda-blue); color: var(--navy-deep);
  border: none; padding: 6px 12px; border-radius: 2px;
  font-family: var(--f-mono); font-size: 10px; letter-spacing: 0.14em;
  text-transform: uppercase; cursor: pointer; font-weight: 600;
}

/* ============== worksheet (interactive form) ============== */
.worksheet {
  display: grid; grid-template-columns: 1fr 1fr; gap: 0;
  border: 1px solid var(--line);
}
.worksheet > div {
  padding: 10px 14px;
  font-size: 13px;
  border-bottom: 1px solid var(--line-2);
  border-right: 1px solid var(--line-2);
}
.worksheet > div:nth-child(even) { border-right: none; }
.worksheet .ws-label {
  font-family: var(--f-mono); font-size: 11px;
  color: var(--muted); letter-spacing: 0.06em;
  display: flex; align-items: center;
}
.worksheet .ws-input { background: var(--paper); }
.worksheet .ws-input input, .worksheet .ws-input select {
  width: 100%; border: none; background: transparent;
  font-family: var(--f-mono); font-size: 13px;
  padding: 2px 0; color: var(--navy);
}
.worksheet .ws-input input:focus, .worksheet .ws-input select:focus {
  outline: none; color: var(--bda-blue);
}

/* ============== callout boxes ============== */
.callout {
  margin: 20px 0;
  padding: 16px 18px;
  border-radius: 2px;
  font-size: 14px;
  line-height: 1.55;
}
.callout-warn {
  background: var(--rust-tint);
  border-left: 3px solid var(--rust);
  color: color-mix(in oklab, var(--rust) 70%, black);
}
.callout-info {
  background: color-mix(in oklab, var(--bda-blue) 10%, var(--paper));
  border-left: 3px solid var(--bda-blue);
  color: var(--navy);
}
.callout-scenario {
  background: var(--paper-2);
  border: 1px solid var(--line);
  padding: 18px 20px;
}
.callout-scenario .label {
  font-family: var(--f-mono); font-size: 10.5px;
  letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--rust); margin-bottom: 8px; font-weight: 600;
}
.callout-scenario h4 {
  font-family: var(--f-serif); font-size: 17px;
  font-style: italic; color: var(--navy);
  margin: 0 0 10px; text-transform: none; letter-spacing: 0;
}

/* ============= cta block within chapter ============= */
.discover-card {
  margin: 28px 0;
  padding: 22px 24px;
  background: var(--navy);
  color: white;
  border-radius: 2px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 16px; align-items: center;
}
.discover-card .label {
  font-family: var(--f-mono); font-size: 10.5px;
  letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--bda-blue); margin-bottom: 6px;
}
.discover-card h5 {
  font-family: var(--f-serif); font-size: 22px; font-weight: 500;
  margin: 0 0 4px; line-height: 1.2;
}
.discover-card p {
  margin: 0; font-size: 14px;
  color: color-mix(in oklab, white 80%, transparent);
}
.discover-card .btn {
  background: var(--bda-blue); color: var(--navy-deep);
  padding: 11px 16px; border-radius: 2px;
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; font-weight: 600;
  text-decoration: none; cursor: pointer;
}

/* ============== brand band (between hero and reader) ============== */
.brand-band {
  background: var(--paper-2);
  border-bottom: 1px solid var(--line);
  padding: 18px 32px;
}
.brand-band .wrap {
  max-width: 1240px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px; flex-wrap: wrap;
}
.brand-band img { height: 28px; width: auto; }
.brand-band .note {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.12em;
  color: var(--muted); text-transform: uppercase;
}
.brand-band .note b { color: var(--navy); }

/* ============== sidebar header logo ============== */
.toc-brand {
  display: flex; align-items: center; gap: 10px;
  padding-bottom: 18px;
  margin-bottom: 22px;
  border-bottom: 1px solid var(--line);
}
.toc-brand img { height: 26px; width: auto; }
.toc-brand .tag {
  font-family: var(--f-mono); font-size: 9px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--muted);
  border-left: 1px solid var(--line); padding-left: 10px;
}

/* ============== chapter eyebrow diamond ============== */
.chapter-eyebrow .ev-mark {
  width: 14px; height: 14px;
  background-image:
    linear-gradient(135deg, transparent 49%, var(--bda-blue) 50%, var(--bda-blue) 51%, transparent 52%),
    linear-gradient(45deg, transparent 49%, var(--navy) 50%, var(--navy) 51%, transparent 52%);
  background-size: 7px 7px;
  background-position: 0 0, 7px 7px;
  flex-shrink: 0;
}
.chapter-eyebrow {
  display: flex; align-items: center; gap: 10px;
}

/* ============== MCA Stacking visualization ============== */
.stacker { padding: 6px 0 4px; }
.stacker-controls {
  display: flex; gap: 8px; justify-content: center; margin-top: 14px; flex-wrap: wrap;
}
.stacker-controls button {
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.1em;
  text-transform: uppercase; padding: 7px 14px;
  background: var(--white); border: 1px solid var(--line);
  color: var(--ink-2); cursor: pointer; border-radius: 2px;
  transition: all .12s;
}
.stacker-controls button:hover { border-color: var(--navy); color: var(--navy); }
.stacker-controls button.primary { background: var(--navy); color: var(--white); border-color: var(--navy); }
.stacker-readout {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px;
  margin-top: 14px;
  padding: 12px;
  background: var(--paper);
  border: 1px solid var(--line-2);
  border-radius: 2px;
}
.stacker-readout .stat .lbl {
  font-family: var(--f-mono); font-size: 9.5px; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 4px;
}
.stacker-readout .stat .val {
  font-family: var(--f-mono); font-size: 18px; font-weight: 500;
  color: var(--navy);
}
.stacker-readout .stat.alert .val { color: var(--rust); }
.stacker-readout .stat.alert .lbl { color: var(--rust); }

/* ============== logo watermark behind footnotes/sections ============== */
.brand-watermark {
  display: flex; align-items: center; gap: 14px;
  margin: 32px 0 0;
  padding: 22px 0 10px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}
.brand-watermark img { height: 22px; opacity: 0.55; }
.brand-watermark .label {
  font-family: var(--f-mono); font-size: 10.5px;
  letter-spacing: 0.16em; text-transform: uppercase;
}

/* ============== chapter video embed ============== */
.chapter-video {
  margin: 0 0 28px;
  padding: 0;
}
.chapter-video-frame {
  background: var(--navy-deep);
  border: 1px solid var(--line);
  border-radius: 3px;
  overflow: hidden;
  position: relative;
  aspect-ratio: 16/9;
}
.chapter-video-frame video {
  width: 100%; height: 100%;
  display: block;
  object-fit: cover;
  background: var(--navy-deep);
}
.chapter-video-frame .video-badge {
  position: absolute;
  top: 12px; left: 12px;
  z-index: 2;
  pointer-events: none;
  background: color-mix(in oklab, var(--navy-deep) 82%, transparent);
  backdrop-filter: blur(4px);
  color: var(--bda-blue);
  font-family: var(--f-mono);
  font-size: 10.5px; letter-spacing: 0.14em;
  text-transform: uppercase; font-weight: 600;
  padding: 6px 10px;
  border: 1px solid color-mix(in oklab, var(--bda-blue) 35%, transparent);
  border-radius: 2px;
}
/* hide the badge once the user starts playing (video gains focus/controls) */
.chapter-video-frame video:not([poster]) + .video-badge { display: none; }
.chapter-video figcaption {
  margin-top: 10px;
  display: flex; gap: 14px; align-items: baseline;
  font-family: var(--f-mono);
  font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--muted);
}
.chapter-video figcaption .vcap-num { color: var(--bda-blue); font-weight: 600; }
.chapter-video figcaption .vcap-text {
  color: var(--ink-2);
  font-family: var(--f-serif);
  font-style: italic; text-transform: none; letter-spacing: 0;
  font-size: 14px; font-weight: 400;
}

/* ============== chapter editorial image ============== */
.chapter-image {
  margin: 0 0 28px;
  padding: 0;
}
.chapter-image-frame {
  background: var(--navy-deep);
  border: 1px solid var(--line);
  border-radius: 3px;
  overflow: hidden;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}
.chapter-image-frame::before {
  content: "Loading…";
  position: absolute;
  inset: 0;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.16em;
  color: color-mix(in oklab, white 35%, transparent);
  text-transform: uppercase;
  z-index: 0;
}
.chapter-image-frame img {
  position: relative; z-index: 1;
  width: 100%; height: 100%;
  object-fit: cover;
  object-position: center;
  display: block;
  background: var(--navy-deep);
}
.chapter-image figcaption {
  margin-top: 10px;
  display: flex; gap: 14px; align-items: baseline;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}
.chapter-image figcaption .cap-num {
  color: var(--bda-blue);
  font-weight: 600;
}
.chapter-image figcaption .cap-text {
  color: var(--ink-2);
  font-family: var(--f-serif);
  font-style: italic;
  text-transform: none;
  letter-spacing: 0;
  font-size: 14px;
  font-weight: 400;
}

/* ============== pro-help mid-document callout ============== */
.prohelp {
  margin: 28px 0;
  padding: 18px 20px;
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 3px solid var(--bda-blue);
  border-radius: 2px;
  display: grid;
  grid-template-columns: 28px 1fr auto;
  gap: 18px; align-items: center;
  position: relative;
}
.prohelp .icon {
  width: 28px; height: 28px;
  background-image: url("assets/bda-mark-navy.png");
  background-size: contain;
  background-repeat: no-repeat;
  background-position: center;
  align-self: flex-start;
  margin-top: 2px;
}
.prohelp .body p { margin: 0 0 6px; font-size: 13.5px; line-height: 1.55; color: var(--ink); }
.prohelp .body p.head { font-style: italic; color: var(--ink-2); font-family: var(--f-serif); font-size: 15px; margin-bottom: 8px; }
.prohelp .body p.fine { color: var(--muted); font-size: 12px; font-family: var(--f-mono); letter-spacing: 0.04em; margin-top: 4px; }
.prohelp .btn {
  background: var(--navy);
  color: var(--white);
  padding: 11px 16px;
  border-radius: 2px;
  font-family: var(--f-mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; font-weight: 600;
  text-decoration: none; white-space: nowrap;
  transition: background .15s;
}
.prohelp .btn:hover { background: var(--bda-blue); color: var(--navy-deep); }

@media (max-width: 640px) {
  .prohelp { grid-template-columns: 1fr; gap: 10px; }
  .prohelp .icon { display: none; }
}

/* ============== chapter end divider ============== */
.chapter-divider {
  display: flex; align-items: center; justify-content: center;
  gap: 8px;
  margin: 40px auto 0;
  color: var(--bda-blue);
  font-size: 8px;
}
.chapter-divider .diamond {
  width: 6px; height: 6px; background: var(--bda-blue);
  transform: rotate(45deg);
}
.chapter-divider .diamond.navy { background: var(--navy); }

/* ============== footer ============== */
footer.site {
  background: var(--navy-deep);
  color: color-mix(in oklab, white 80%, transparent);
  padding: 60px 32px;
}
footer.site .wrap {
  max-width: 1240px; margin: 0 auto;
  display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 40px;
}
footer.site img { width: 220px; margin-bottom: 16px; }
footer.site h4 {
  font-family: var(--f-mono); font-size: 11px;
  letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--bda-blue); margin: 0 0 14px;
}
footer.site a {
  color: color-mix(in oklab, white 80%, transparent);
  display: block; padding: 4px 0;
  text-decoration: none; font-size: 14px;
}
footer.site a:hover { color: var(--bda-blue); }
footer.site .fine {
  max-width: 1240px; margin: 32px auto 0; padding-top: 24px;
  border-top: 1px solid color-mix(in oklab, white 10%, transparent);
  font-family: var(--f-mono); font-size: 10.5px;
  letter-spacing: 0.08em; color: color-mix(in oklab, white 50%, transparent);
}

/* ============== footnotes section ============== */
.footnotes {
  margin: 80px 0 0;
  padding: 32px 0;
  border-top: 1px solid var(--line);
}
.footnotes h3 {
  font-family: var(--f-mono); font-size: 11px;
  letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--muted); margin: 0 0 16px;
}
.footnotes ol {
  padding-left: 22px; font-size: 13px; color: var(--ink-2);
  line-height: 1.6;
}
.footnotes li { margin: 6px 0; }
.footnotes li::marker {
  color: var(--bda-blue); font-family: var(--f-mono);
}

/* ============== responsive ============== */
@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; padding: 50px 28px 70px; }
  .reader { grid-template-columns: 1fr; gap: 32px; }
  aside.toc {
    position: static;
    max-height: none;
    border-bottom: 1px solid var(--line);
    padding-bottom: 16px;
  }
}
@media (max-width: 640px) {
  .hero-bar img { width: 160px; }
  .hero-grid { padding: 40px 20px 60px; }
  .reader { padding: 40px 20px 60px; }
  .worksheet { grid-template-columns: 1fr; }
  .worksheet > div { border-right: none; }
  .calc-row { grid-template-columns: 1fr; }
  .iftile { grid-template-columns: 1fr; gap: 8px; }
  .iftile .arrow { text-align: left; }
  .flow .node { min-width: 0; width: 100%; }
}