/* DELETE: Elon's method for your training. Same field-manual look as The Bigger Sandbox. Field-manual look: black page, white type, one emerald pop per screen,
   hairline rules, square corners. Brand: hmn-aide-brand-kit/BRAND-DIRECTION.md */
:root {
  --ink: #000;
  --paper: #fff;
  --emerald: #13a572;
  --rule: #fff;
  --dim: #fff;
  --faint: #fff;
  --w: 560px;
}
* { box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }
html { background: var(--ink); color-scheme: dark; }
body {
  background: var(--ink);
  color: var(--paper);
  font-family: Inter, system-ui, sans-serif;
  font-weight: 400;
  line-height: 1.4;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  padding-bottom: env(safe-area-inset-bottom);
}
main { max-width: var(--w); margin: 0 auto; overflow-x: clip; }
button { font: inherit; color: inherit; border: 0; background: none; cursor: pointer; border-radius: 0; }
input { font: inherit; border-radius: 0; }
a { color: inherit; }

/* reading progress: one hairline across the top */
.progress { position: fixed; left: 0; top: 0; height: 1px; width: 100%; background: transparent; z-index: 30; }
.progress i { display: block; height: 100%; width: 0; background: var(--paper); }

/* ---------- cover ---------- */
.cover { position: relative; min-height: 100svh; display: flex; flex-direction: column; justify-content: center; padding: 72px 16px 72px; overflow: hidden; }
.cover canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
.cover > * { position: relative; }
.cover .brand { position: absolute; top: 24px; left: 16px; height: 100px; }
.stack div { text-transform: uppercase; line-height: .84; letter-spacing: -.055em; white-space: nowrap; }
.stack .s1 { font-weight: 500; font-size: min(15vw, 82px); }
.stack .s2 { font-weight: 800; font-size: min(25vw, 136px); color: var(--emerald); }
.stack .s3 { font-weight: 800; font-size: min(21vw, 116px); margin-left: -.03em; }
.cover .sub { font-size: 19px; font-weight: 500; line-height: 1.3; max-width: 26ch; margin-top: 24px; }
.cover .by { font-size: 13px; color: var(--dim); margin-top: 10px; }

/* ---------- chapters ---------- */
.ch { padding: 40px 0 48px; border-top: 1px solid var(--rule); }
.ch-head { padding: 0 16px; }
.ch .num { font-weight: 800; font-size: 13px; letter-spacing: .14em; color: var(--paper); }
.ch h2 { font-weight: 500; font-size: clamp(30px, 9vw, 44px); line-height: .98; letter-spacing: -.035em; text-transform: uppercase; margin-top: 10px; }
.ch h2 b { font-weight: 800; }
.body { padding: 0 16px; }
.body p { font-size: 17px; line-height: 1.6; color: var(--paper); margin-top: 18px; max-width: 62ch; }
.body p strong { color: var(--paper); font-weight: 700; }
.body ul { list-style: none; margin-top: 18px; border-top: 1px solid var(--rule); }
.body li { font-size: 17px; line-height: 1.5; padding: 14px 0; border-bottom: 1px solid var(--rule); color: var(--paper); }
.body .quote { font-size: 22px; font-weight: 500; line-height: 1.3; letter-spacing: -.015em; margin-top: 22px; padding: 18px 0; border-top: 1px solid var(--rule); color: var(--paper); }
.body .quote + .quote { margin-top: 0; }
.first .body p:first-child { margin-top: 24px; }

/* the visual each chapter opens on: full width, square corners, survey marks drawn inside */
.vis { position: relative; margin: 24px 0 4px; width: 100%; background: var(--ink); }
.vis canvas { display: block; width: 100%; height: 100%; }
.vis.r45 { aspect-ratio: 4 / 5; }
.vis.r11 { aspect-ratio: 1 / 1; }
.vis.r914 { aspect-ratio: 9 / 14; }
.vis.r43 { aspect-ratio: 4 / 3; }
.vis .cap { padding: 10px 16px 0; font-size: 12px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--dim); }

/* toggles under an interactive visual: plain uppercase text, a rule under each */
.toggles { display: flex; flex-wrap: wrap; gap: 0 18px; padding: 6px 16px 0; }
.toggles button { font-size: 13px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; padding: 12px 0 8px; color: var(--faint); border-bottom: 1px solid transparent; }
.toggles button:focus { outline: none; }
.toggles button:focus-visible { outline: 1px solid var(--paper); outline-offset: 2px; }
.toggles button[aria-pressed="true"] { color: var(--paper); border-bottom-color: var(--paper); }

/* flat type slide */
.slide { padding: 56px 16px 40px; }
.slide div { font-weight: 500; font-size: clamp(42px, 13vw, 72px); line-height: .92; letter-spacing: -.045em; text-transform: uppercase; }
.slide b { font-weight: 800; color: var(--emerald); }

/* film still */
.still { margin-top: 24px; aspect-ratio: 4 / 5; overflow: hidden; background: #000; }
.still img { width: 100%; height: 100%; object-fit: cover; display: block; }

/* ---------- book link (chapter 10): the one emerald pop ---------- */
.book { display: flex; justify-content: space-between; align-items: center; margin-top: 30px; padding: 18px 0; border-top: 1px solid var(--emerald); border-bottom: 1px solid var(--emerald); color: var(--emerald); text-decoration: none; font-size: 20px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; }
.book::after { content: '\2192'; font-weight: 500; }
.book:active { opacity: .7; }

.end { padding: 40px 16px 72px; border-top: 1px solid var(--rule); font-size: 12px; color: var(--faint); }

/* reveal on scroll: opacity only, nothing flies in */
.rv { opacity: 0; transition: opacity .8s ease; }
.rv.in { opacity: 1; }

@media (prefers-reduced-motion: reduce) {
  .rv { opacity: 1; transition: none; }
}

/* all videos play in black and white */
video { filter: grayscale(1); }

/* ---------- cover title ---------- */
.stack .t1 { font-weight: 500; font-size: min(8vw, 44px); }
.stack .t2 { font-weight: 800; font-size: min(9.4vw, 52px); }
.stack .t3 { font-weight: 800; font-size: min(17vw, 94px); color: var(--emerald); }

/* ---------- ask yourself ---------- */
.ask { margin-top: 26px; padding: 18px 0; border-top: 1px solid var(--emerald); border-bottom: 1px solid var(--emerald); font-size: 19px; line-height: 1.4; font-weight: 600; }
.ask b { color: var(--emerald); font-weight: 800; letter-spacing: .06em; text-transform: uppercase; font-size: 13px; display: block; margin-bottom: 6px; }

/* ---------- the 5 steps slide ---------- */
.steps { padding: 34px 16px 10px; }
.steps div { display: flex; gap: 16px; align-items: baseline; padding: 10px 0; border-bottom: 1px solid var(--rule); }
.steps span { font-size: 13px; font-weight: 800; letter-spacing: .1em; width: 24px; flex: none; }
.steps strong { font-size: clamp(28px, 8.5vw, 42px); font-weight: 800; letter-spacing: -.035em; line-height: 1; text-transform: uppercase; }

/* ---------- audit: tap to check ---------- */
.audit { list-style: none; margin-top: 18px; border-top: 1px solid var(--rule); }
.audit li { padding: 0; border-bottom: 1px solid var(--rule); }
.audit button { display: flex; gap: 14px; width: 100%; text-align: left; padding: 16px 0; font-size: 17px; line-height: 1.45; }
.audit .box { flex: none; width: 22px; height: 22px; border: 1px solid var(--paper); margin-top: 1px; display: grid; place-items: center; font-size: 14px; font-weight: 800; }
.audit li.done .box { background: var(--emerald); border-color: var(--emerald); color: #000; }
.audit li.done .box::after { content: '\2713'; }
.audit .no { font-size: 12px; font-weight: 800; letter-spacing: .1em; margin-top: 3px; flex: none; width: 18px; }