/* =========================================================================
   25 REMAKE WORK — twenty-five.ai
   Palette sampled from the printed cover: warm charcoal ground, neon
   spectrum azure → indigo → magenta → orange → amber.
   No web fonts by design. Nothing blocks first paint.
   ========================================================================= */

:root {
  /* ground — must match GROUND_FLAT in tools/generate_frames.py */
  --ground: #0e0d0c;
  --ground-2: #161513;
  --ground-3: #1e1c1a;
  --hair: rgba(255, 255, 255, .10);
  --hair-soft: rgba(255, 255, 255, .055);

  --paper: #f7f5f2;
  --paper-2: #ece8e2;
  --ink: #131211;
  --ink-2: #3d3a37;
  --ink-3: #6d6862;

  --on-dark: #f2efec;   /* 15.9:1 on --ground */
  --on-dark-2: #a8a29b; /*  7.7:1 */
  --on-dark-3: #847e76; /*  4.9:1 — the floor, so even 11px labels pass AA */

  /* cover spectrum */
  --azure: #56b8f0;
  --indigo: #5c6fe8;
  --magenta: #e8397a;
  --orange: #f2762e;
  --amber: #f0b72f;
  --spectrum: linear-gradient(90deg, var(--azure), var(--indigo), var(--magenta), var(--orange), var(--amber));

  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --serif: "TeX Gyre Pagella", Palatino, "Palatino Linotype", "Book Antiqua", Georgia, Cambria, "Times New Roman", serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --measure: 34rem;
  --gutter: clamp(1.25rem, 5vw, 4rem);
  --shell: 76rem;
  --step: clamp(4.5rem, 11vh, 9rem);
}

/* ------------------------------------------------------------------ reset */
*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

body {
  margin: 0;
  background: var(--ground);
  color: var(--on-dark);
  font-family: var(--serif);
  font-size: clamp(1.0625rem, 1.6vw, 1.1875rem);
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

canvas, svg { display: block; max-width: 100%; }
/* height:auto matters: these images carry width/height attributes so the
   browser can reserve space, and without it max-width would squash them. */
img { display: block; max-width: 100%; height: auto; }
h1, h2, h3, h4 { margin: 0; font-weight: 700; }
p { margin: 0 0 1.15em; }
p:last-child { margin-bottom: 0; }

a { color: inherit; }
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--azure);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--paper); color: var(--ink);
  padding: .75rem 1.15rem; z-index: 100; font-family: var(--sans);
}
.skip:focus { left: .75rem; top: .75rem; }

.vh {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ------------------------------------------------------------ typography */
.display {
  font-family: var(--sans);
  font-weight: 800;
  letter-spacing: -.032em;
  line-height: .96;
  text-wrap: balance;
}

.h1 { font-size: clamp(2.4rem, 7.4vw, 5.6rem); }
.h2 { font-size: clamp(1.9rem, 4.6vw, 3.4rem); }
.h3 { font-size: clamp(1.3rem, 2.4vw, 1.85rem); letter-spacing: -.022em; }

.eyebrow {
  font-family: var(--sans);
  font-size: .6875rem;
  font-weight: 700;
  letter-spacing: .19em;
  text-transform: uppercase;
  color: var(--on-dark-3);
  margin: 0 0 1.4rem;
}
.eyebrow.on-paper { color: var(--ink-3); }
.eyebrow .num {
  background: var(--spectrum);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-right: .7rem;
}

.lede {
  font-size: clamp(1.15rem, 2.1vw, 1.45rem);
  line-height: 1.5;
  color: var(--on-dark-2);
}
.lede.on-paper { color: var(--ink-2); }

.dek { font-family: var(--sans); font-size: .9375rem; line-height: 1.55; }

em { font-style: italic; }
strong { font-weight: 600; }

.gradient-text {
  background: var(--spectrum);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}

.rule-spectrum {
  height: 2px; width: 5.5rem; border: 0; margin: 0 0 2rem;
  background: var(--spectrum);
  border-radius: 2px;
}

/* ---------------------------------------------------------------- layout */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.shell--narrow { max-width: 48rem; }

.band { padding-block: var(--step); position: relative; }
.band--paper { background: var(--paper); color: var(--ink); }
.band--paper .lede { color: var(--ink-2); }
.band--tint { background: var(--ground-2); }
.band--edge { border-top: 1px solid var(--hair-soft); }
.band--paper.band--edge { border-top-color: rgba(0, 0, 0, .09); }

.measure { max-width: var(--measure); }

/* ---------------------------------------------------------------- header */
.masthead {
  position: fixed; inset: 0 0 auto 0; z-index: 50;
  display: flex; align-items: center; gap: 1rem;
  padding: .85rem var(--gutter);
  font-family: var(--sans);
  background: color-mix(in srgb, var(--ground) 72%, transparent);
  border-bottom: 1px solid transparent;
  transition: background .25s ease, border-color .25s ease;
}
@supports not (background: color-mix(in srgb, red 50%, blue)) {
  .masthead { background: rgba(14, 13, 12, .72); }
}
.masthead.is-stuck {
  background: rgba(14, 13, 12, .93);
  border-bottom-color: var(--hair-soft);
  backdrop-filter: saturate(140%) blur(12px);
  -webkit-backdrop-filter: saturate(140%) blur(12px);
}

.brand {
  display: inline-flex; align-items: baseline; gap: .55rem;
  text-decoration: none; margin-right: auto;
}
.brand b {
  font-weight: 800; font-size: 1.2rem; letter-spacing: -.03em;
  background: var(--spectrum);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.brand span {
  font-size: .6875rem; font-weight: 600; letter-spacing: .18em;
  text-transform: uppercase; color: var(--on-dark-2);
}

.nav { display: flex; align-items: center; gap: .35rem; min-width: 0; }
/* The pill must never be the thing that gets squeezed off-screen. */
.nav .btn { flex: 0 0 auto; }
.nav a {
  font-size: .8125rem; font-weight: 500; letter-spacing: .01em;
  text-decoration: none; color: var(--on-dark-2);
  padding: .5rem .7rem; border-radius: 999px;
  transition: color .18s ease, background .18s ease;
}
.nav a:hover { color: var(--on-dark); background: rgba(255, 255, 255, .06); }
@media (max-width: 47.99em) { .nav .nav-hide { display: none; } }

/* ---- phone header -------------------------------------------------------
   At 393px the wordmark plus two links plus the pill overflowed and pushed
   "Get the book" off the right edge. Drop the wordmark to the bare 25 mark
   and tighten everything; the CTA is the last thing that may shrink. */
@media (max-width: 30em) {
  .masthead { padding: .7rem .9rem; gap: .5rem; }
  .brand { gap: 0; }
  .brand span { display: none; }
  .brand b { font-size: 1.35rem; }
  .nav { gap: .1rem; }
  .nav a { font-size: .8125rem; padding: .45rem .45rem; }
  .nav .btn--sm { padding: .5rem .85rem; font-size: .8125rem; }
}
/* Very narrow (SE-class): the pill alone carries the action. */
@media (max-width: 22em) {
  .nav a:not(.btn) { display: none; }
}

/* --------------------------------------------------------------- buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .55rem;
  font-family: var(--sans); font-size: .875rem; font-weight: 650;
  letter-spacing: .01em; text-decoration: none;
  padding: .85rem 1.5rem; border-radius: 999px; border: 1px solid transparent;
  cursor: pointer; white-space: nowrap;
  transition: transform .16s ease, opacity .16s ease, background .16s ease, border-color .16s ease;
}
.btn:active { transform: translateY(1px); }

.btn--primary { background: var(--paper); color: var(--ink); }
.btn--primary:hover { background: #fff; }

.btn--spectrum {
  color: #08080a;              /* stays >=4.5:1 across the whole gradient */
  background: var(--spectrum);
  background-size: 220% 100%;
  background-position: 18% 0;
  font-weight: 700;
}
.btn--spectrum:hover { background-position: 72% 0; }

.btn--ghost {
  border-color: var(--hair); color: var(--on-dark);
  background: rgba(255, 255, 255, .03);
}
.btn--ghost:hover { border-color: rgba(255, 255, 255, .28); background: rgba(255, 255, 255, .07); }

.btn--ink { background: var(--ink); color: var(--paper); }
.btn--ink:hover { background: #000; }

.btn--outline-ink { border-color: rgba(0, 0, 0, .2); color: var(--ink); }
.btn--outline-ink:hover { border-color: rgba(0, 0, 0, .45); background: rgba(0, 0, 0, .04); }

.btn--sm { padding: .6rem 1.05rem; font-size: .8125rem; }
.btn-row { display: flex; flex-wrap: wrap; gap: .75rem; align-items: center; }

.hint { font-family: var(--sans); font-size: .8125rem; color: var(--on-dark-3); }
.hint.on-paper { color: var(--ink-3); }

/* ============================================================ SCROLL HERO
   A pinned plate. The spacer owns the scroll distance; the canvas is drawn
   from a preloaded frame sequence, one draw per animation frame, only when
   the target frame index actually changes.
   ========================================================================= */
.hero { position: relative; }

.hero__track {
  position: relative;
  height: 560vh;              /* scroll distance for the whole sequence */
}

.hero__stage {
  position: sticky; top: 0;
  height: 100svh; min-height: 34rem;
  overflow: hidden;
  display: grid;
}

.hero__canvas {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  background: var(--ground);
}

/* Seam-free fade into the page, and a scrim that guarantees the bottom-aligned
   copy stays legible even on a short laptop window where the drawing reaches
   further down than intended. */
.hero__stage::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background:
    linear-gradient(to bottom,
      var(--ground) 0,
      rgba(14, 13, 12, 0) 13%,
      rgba(14, 13, 12, 0) 44%,
      rgba(14, 13, 12, .62) 66%,
      rgba(14, 13, 12, .93) 84%,
      var(--ground) 100%);
}

/* Copy lives in the bottom third; the plate draws its subject in the top two
   thirds. Nothing ever sits on top of the animation. */
.hero__beats {
  position: relative; z-index: 2;
  display: grid; place-items: end center; align-content: end;
  padding: 5.5rem var(--gutter) clamp(3.25rem, 7vh, 5.5rem);
}

.beat {
  grid-area: 1 / 1;
  max-width: 40rem; text-align: center;
  opacity: 0; transform: translateY(1.1rem);
  transition: opacity .5s ease, transform .5s ease;
  will-change: opacity, transform;
}
.beat[data-on="1"] { opacity: 1; transform: none; }

.beat__kicker {
  font-family: var(--mono); font-size: .75rem; letter-spacing: .16em;
  text-transform: uppercase; color: var(--on-dark-3);
  margin: 0 0 1.1rem;
}
.beat__kicker b { color: var(--on-dark); font-weight: 600; }
.beat p.beat__body {
  font-size: clamp(1.05rem, 1.9vw, 1.3rem);
  color: var(--on-dark-2); margin: 1.1rem auto 0; max-width: 32rem;
}
.beat .btn-row { justify-content: center; margin-top: 2rem; }

/* Short windows: the drawing needs the room more than the type does. */
@media (max-height: 46em) {
  .beat .h1 { font-size: clamp(2rem, 5.4vw, 3.4rem); }
  .beat .h2 { font-size: clamp(1.6rem, 3.6vw, 2.4rem); }
  .beat p.beat__body { font-size: 1rem; max-width: 30rem; }
  .beat__kicker { margin-bottom: .75rem; }
  .hero__beats { padding-bottom: 2.5rem; }
}

/* the very first beat carries the title, so it gets extra weight */
.beat--title .h1 { letter-spacing: -.04em; }
.beat--title .byline {
  font-family: var(--sans); font-size: .75rem; font-weight: 600;
  letter-spacing: .22em; text-transform: uppercase;
  color: var(--on-dark-3); margin: 1.6rem 0 0;
}

.hero__cue {
  position: absolute; z-index: 3; right: var(--gutter); bottom: 1.5rem;
  font-family: var(--mono); font-size: .6875rem; letter-spacing: .18em;
  text-transform: uppercase; color: var(--on-dark-3);
  display: flex; flex-direction: column; align-items: center; gap: .5rem;
  transition: opacity .4s ease;
}
.hero__cue i {
  display: block; width: 1px; height: 2rem;
  background: linear-gradient(to bottom, var(--on-dark-3), transparent);
  animation: cue 2.4s ease-in-out infinite;
}
@keyframes cue { 0%, 100% { opacity: .25; transform: scaleY(.6); } 50% { opacity: 1; transform: scaleY(1); } }
.hero.is-scrolled .hero__cue { opacity: 0; }

/* loading shim — a hairline that fills while frames stream in */
.hero__load {
  position: absolute; z-index: 4; left: 50%; bottom: 0; height: 2px;
  width: min(18rem, 40vw); transform: translateX(-50%);
  background: rgba(255, 255, 255, .08); overflow: hidden;
  transition: opacity .4s ease .2s;
}
.hero__load i { display: block; height: 100%; width: 0%; background: var(--spectrum); transition: width .2s linear; }
.hero.is-ready .hero__load { opacity: 0; }

/* ---- static fallback: reduced motion, no JS, or frames unavailable ---- */
.hero.is-static .hero__track { height: auto; }
.hero.is-static .hero__stage {
  position: relative; height: auto; min-height: 0;
  display: block; padding-block: 0;
}
.hero.is-static .hero__canvas { display: none; }
.hero.is-static .hero__poster { display: block; }
.hero.is-static .hero__cue,
.hero.is-static .hero__load { display: none; }
.hero.is-static .hero__stage::after { display: none; }
.hero.is-static .hero__beats {
  display: block; padding-block: 8rem 4rem;
  max-width: var(--shell); margin-inline: auto;
}
.hero.is-static .beat {
  opacity: 1; transform: none; text-align: left;
  max-width: 40rem; margin: 0 0 4.5rem;
  padding-left: 1.25rem; border-left: 2px solid var(--hair-soft);
}
.hero.is-static .beat:last-of-type { margin-bottom: 0; }
.hero.is-static .beat .btn-row { justify-content: flex-start; }
.hero.is-static .beat p.beat__body { margin-inline: 0; }

.hero__poster {
  display: none;
  width: 100%; max-width: 52rem;
  margin: 7rem auto 0;
  border-radius: 10px; border: 1px solid var(--hair-soft);
}
.hero.is-static .hero__beats { padding-block: 3rem 4rem; }

/* ---- static hero on a phone --------------------------------------------
   The desktop treatment (a floating rounded plate plus a left hairline on
   every beat) reads as a document on a phone, not as an app. Full-bleed the
   plate, drop the rule, tighten the rhythm. */
@media (max-width: 34em) {
  .hero.is-static .hero__poster {
    width: 100vw;
    max-width: none;
    margin: 4.5rem 0 0 calc(50% - 50vw);
    border-radius: 0;
    border-left: 0;
    border-right: 0;
  }
  .hero.is-static .hero__beats { padding-block: 2rem 2.5rem; }
  .hero.is-static .beat {
    border-left: 0;
    padding-left: 0;
    margin-bottom: 2.75rem;
    max-width: none;
  }
  .hero.is-static .beat .h1 { font-size: clamp(1.9rem, 8.2vw, 2.6rem); }
  .hero.is-static .beat .h2 { font-size: clamp(1.5rem, 6.6vw, 2.1rem); }
  .hero.is-static .beat p.beat__body { font-size: 1.0625rem; }
  .hero.is-static .beat .btn-row { flex-direction: column; align-items: stretch; }
  .hero.is-static .beat .btn-row .btn { justify-content: center; }
}

/* ------------------------------------------------------------- diagnosis */
.stat-row {
  display: grid; gap: 1px;
  grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
  background: var(--hair-soft);
  border: 1px solid var(--hair-soft); border-radius: 10px; overflow: hidden;
  margin-top: 3rem;
}
.stat {
  background: var(--ground); padding: 1.75rem 1.5rem;
}
.stat b {
  display: block; font-family: var(--sans); font-weight: 800;
  font-size: clamp(2rem, 4.4vw, 3rem); letter-spacing: -.035em; line-height: 1;
  margin-bottom: .55rem;
}
.stat:nth-child(1) b { color: var(--azure); }
.stat:nth-child(2) b { color: var(--magenta); }
.stat:nth-child(3) b { color: var(--amber); }
.stat span { font-family: var(--sans); font-size: .875rem; color: var(--on-dark-2); line-height: 1.5; display: block; }
.stat i { display: block; font-family: var(--sans); font-style: normal; font-size: .75rem; color: var(--on-dark-3); margin-top: .5rem; }

/* --------------------------------------------------------------- columns */
.cols {
  display: grid; gap: clamp(1.5rem, 3vw, 2.5rem);
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  margin-top: 3.5rem;
}
.col h3 { margin-bottom: .7rem; }
.col p { font-family: var(--sans); font-size: .9375rem; line-height: 1.6; color: var(--on-dark-2); }
.band--paper .col p { color: var(--ink-2); }
.col__no {
  font-family: var(--mono); font-size: .75rem; letter-spacing: .12em;
  display: block; margin-bottom: 1rem; color: var(--on-dark-3);
}
.band--paper .col__no { color: var(--ink-3); }
.col--rule { padding-top: 1.5rem; border-top: 1px solid var(--hair); }
.band--paper .col--rule { border-top-color: rgba(0, 0, 0, .14); }
.col:nth-child(1).col--rule { border-top-color: var(--azure); }
.col:nth-child(2).col--rule { border-top-color: var(--magenta); }
.col:nth-child(3).col--rule { border-top-color: var(--amber); }

/* ------------------------------------------------------------ pull quote */
.pull {
  margin: 0; padding: 0;
  max-width: 40rem;
}
.pull blockquote {
  margin: 0; font-size: clamp(1.35rem, 3vw, 2rem); line-height: 1.34;
  letter-spacing: -.012em;
}
.pull blockquote p { margin-bottom: .8em; }
.pull figcaption {
  font-family: var(--sans); font-size: .8125rem; letter-spacing: .02em;
  color: var(--ink-3); margin-top: 1.5rem;
}
.band:not(.band--paper) .pull figcaption { color: var(--on-dark-3); }

/* ----------------------------------------------------------------- book */
.book {
  display: grid; gap: clamp(2rem, 5vw, 4rem); align-items: start;
  grid-template-columns: minmax(0, 1fr);
}
@media (min-width: 52em) {
  .book { grid-template-columns: minmax(15rem, 20rem) minmax(0, 1fr); }
}

/* The cover is a dark object on a light band, so it needs a real shadow and a
   hairline to sit on the paper rather than float. It is also the biggest
   click target for "buy", so it is a link. */
.book__cover {
  display: block; position: relative; border-radius: 5px; overflow: hidden;
  background: #0a0a09;
  aspect-ratio: 672 / 1018;
  box-shadow:
    0 1.25rem 2.5rem -.5rem rgba(0, 0, 0, .45),
    0 2.5rem 5rem -1rem rgba(0, 0, 0, .3),
    0 0 0 1px rgba(0, 0, 0, .22);
  transition: transform .35s cubic-bezier(.2, .7, .2, 1), box-shadow .35s ease;
}
.book__cover img { width: 100%; height: 100%; object-fit: cover; }
a.book__cover:hover {
  transform: translateY(-4px) scale(1.008);
  box-shadow:
    0 1.75rem 3rem -.5rem rgba(0, 0, 0, .5),
    0 3.5rem 6rem -1rem rgba(0, 0, 0, .34),
    0 0 0 1px rgba(0, 0, 0, .26);
}
@media (prefers-reduced-motion: reduce) {
  .book__cover, a.book__cover:hover { transition: none; transform: none; }
}

/* small cover, used in the reading section header */
.cover-chip {
  display: block; width: clamp(6rem, 14vw, 8.5rem); border-radius: 4px;
  overflow: hidden; flex: 0 0 auto;
  box-shadow: 0 .75rem 1.75rem rgba(0, 0, 0, .55), 0 0 0 1px rgba(255, 255, 255, .08);
}

.formats { list-style: none; margin: 2rem 0 0; padding: 0; }
.formats li {
  display: flex; align-items: baseline; gap: 1rem;
  padding: .95rem 0; border-top: 1px solid rgba(0, 0, 0, .12);
  font-family: var(--sans); font-size: .9375rem;
}
.band:not(.band--paper) .formats li { border-top-color: var(--hair-soft); }
.formats li:last-child { border-bottom: 1px solid rgba(0, 0, 0, .12); }
.band:not(.band--paper) .formats li:last-child { border-bottom-color: var(--hair-soft); }
.formats b { font-weight: 650; min-width: 6.5rem; }
.formats .price { margin-left: auto; font-variant-numeric: tabular-nums; font-weight: 650; }
.formats .note { color: var(--ink-3); font-size: .8125rem; }
.band:not(.band--paper) .formats .note { color: var(--on-dark-3); }

.spec {
  list-style: none; margin: 1.75rem 0 0; padding: 0;
  display: flex; flex-wrap: wrap; gap: .4rem 1.5rem;
  font-family: var(--mono); font-size: .75rem; letter-spacing: .04em;
  color: var(--ink-3);
}
.band:not(.band--paper) .spec { color: var(--on-dark-3); }

/* ------------------------------------------------------------- contents */
.toc { list-style: none; margin: 2.5rem 0 0; padding: 0; display: grid; gap: 1px;
  background: rgba(0, 0, 0, .1); border-block: 1px solid rgba(0, 0, 0, .1); }
.band:not(.band--paper) .toc { background: var(--hair-soft); border-block-color: var(--hair-soft); }
.toc li {
  background: var(--paper); padding: 1.15rem 0;
  display: grid; gap: .2rem 1.1rem;
  grid-template-columns: 7.5rem minmax(0, 1fr);
  align-items: baseline;
}
.band:not(.band--paper) .toc li { background: var(--ground); }

/* Explicit placement for all three children. Relying on auto-placement here
   was a bug: a bare `.toc span` rule also matched .part and pushed the label
   into column two. */
.toc .part {
  grid-column: 1; grid-row: 1;
  font-family: var(--mono); font-size: .6875rem; letter-spacing: .12em;
  text-transform: uppercase; color: var(--ink-3);
}
.band:not(.band--paper) .toc .part { color: var(--on-dark-3); }
.toc b {
  grid-column: 2; grid-row: 1;
  font-family: var(--sans); font-weight: 650; font-size: .9375rem;
}
.toc li > span:not(.part) {
  grid-column: 2; grid-row: 2;
  font-family: var(--sans); font-size: .8125rem; color: var(--ink-3);
}
.band:not(.band--paper) .toc li > span:not(.part) { color: var(--on-dark-3); }
@media (max-width: 34em) {
  .toc li { grid-template-columns: minmax(0, 1fr); }
  .toc .part, .toc b, .toc li > span:not(.part) { grid-column: 1; }
  .toc .part { grid-row: 1; }
  .toc b { grid-row: 2; }
  .toc li > span:not(.part) { grid-row: 3; }
}

/* ----------------------------------------------------------- proof slot
   Empty-state-safe: with zero endorsements this reads as a deliberate
   invitation, not a gap. Nothing here pretends to be a review.
   ========================================================================= */
.proof {
  border: 1px solid var(--hair-soft); border-radius: 12px;
  padding: clamp(1.75rem, 4vw, 3rem);
  background: linear-gradient(180deg, var(--ground-2), var(--ground));
}
.proof__grid { display: none; }
.proof:not(.is-empty) .proof__grid {
  display: grid; gap: 1.25rem;
  grid-template-columns: repeat(auto-fit, minmax(17rem, 1fr));
  margin-top: 2rem;
}
.proof:not(.is-empty) .proof__invite { display: none; }
.quote {
  margin: 0; padding: 1.4rem 1.5rem; border-radius: 10px;
  background: rgba(255, 255, 255, .035); border: 1px solid var(--hair-soft);
}
.quote p { font-size: 1rem; line-height: 1.55; margin-bottom: 1rem; }
.quote footer { font-family: var(--sans); font-size: .8125rem; color: var(--on-dark-3); }

/* ---------------------------------------------------------------- talks */
.talks { display: grid; gap: 1px; background: var(--hair-soft);
  border: 1px solid var(--hair-soft); border-radius: 12px; overflow: hidden;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr)); margin-top: 3rem; }
.talk { background: var(--ground); padding: 1.9rem 1.6rem; }
.talk h3 { font-family: var(--sans); font-size: 1.0625rem; letter-spacing: -.015em; margin-bottom: .8rem; }
.talk p { font-family: var(--sans); font-size: .875rem; line-height: 1.6; color: var(--on-dark-2); }
.talk__meta {
  list-style: none; margin: 1.3rem 0 0; padding: 0;
  font-family: var(--mono); font-size: .6875rem; letter-spacing: .08em;
  text-transform: uppercase; color: var(--on-dark-3);
  display: grid; gap: .4rem;
}
.talk__meta li::before { content: "— "; opacity: .5; }
.talk__tag {
  display: inline-block; margin-bottom: 1rem; height: 2px; width: 2.25rem;
  background: var(--spectrum); border-radius: 2px;
}

.facts { list-style: none; margin: 2.5rem 0 0; padding: 0;
  display: flex; flex-wrap: wrap; gap: .5rem; }
.facts li {
  font-family: var(--sans); font-size: .8125rem; font-weight: 550;
  padding: .45rem .9rem; border-radius: 999px;
  border: 1px solid var(--hair); color: var(--on-dark-2);
}

/* ----------------------------------------------------------------- form */
.form { margin-top: 3rem; max-width: 44rem; }
.field-grid { display: grid; gap: 1.1rem; grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); }
.field { display: grid; gap: .45rem; }
.field--wide { grid-column: 1 / -1; }
.field label {
  font-family: var(--sans); font-size: .75rem; font-weight: 650;
  letter-spacing: .09em; text-transform: uppercase; color: var(--on-dark-2);
}
.field .req { color: var(--magenta); }
.field input, .field select, .field textarea {
  font-family: var(--sans); font-size: .9375rem; color: var(--on-dark);
  background: rgba(255, 255, 255, .04);
  border: 1px solid var(--hair); border-radius: 8px;
  padding: .8rem .9rem; width: 100%;
  transition: border-color .16s ease, background .16s ease;
}
.field textarea { min-height: 7.5rem; resize: vertical; font-family: var(--serif); font-size: 1rem; }
.field input:hover, .field select:hover, .field textarea:hover { border-color: rgba(255, 255, 255, .24); }
.field input::placeholder, .field textarea::placeholder { color: var(--on-dark-3); }
.field select { appearance: none; -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--on-dark-2) 50%),
                    linear-gradient(135deg, var(--on-dark-2) 50%, transparent 50%);
  background-position: calc(100% - 1.15rem) 55%, calc(100% - .8rem) 55%;
  background-size: .35rem .35rem, .35rem .35rem; background-repeat: no-repeat; }
.field select option { background: var(--ground-3); color: var(--on-dark); }
.form__foot { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; margin-top: 1.75rem; }
.hp { position: absolute; left: -9999px; }

/* --------------------------------------------------------------- author */
.author { display: grid; gap: 2rem; align-items: start; }
@media (min-width: 46em) { .author { grid-template-columns: 1fr 1.35fr; } }
.author__card {
  border-left: 2px solid transparent;
  border-image: var(--spectrum) 1;
  padding-left: 1.5rem;
}

/* --------------------------------------------------------------- footer */
.foot {
  border-top: 1px solid var(--hair-soft);
  padding-block: 3.5rem 4rem;
  font-family: var(--sans); font-size: .8125rem; color: var(--on-dark-3);
}
.foot__grid { display: flex; flex-wrap: wrap; gap: 2rem 3rem; justify-content: space-between; }
.foot nav { display: grid; gap: .6rem; }
.foot a { text-decoration: none; color: var(--on-dark-2); }
.foot a:hover { color: var(--on-dark); text-decoration: underline; text-underline-offset: .2em; }
.foot__mark { font-family: var(--sans); font-weight: 800; font-size: 1.1rem; letter-spacing: -.03em;
  background: var(--spectrum); -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; }

/* -------------------------------------------------------------- reveals */
.rise { opacity: 0; transform: translateY(1.4rem); }
.rise.is-in { opacity: 1; transform: none; transition: opacity .7s ease, transform .7s cubic-bezier(.2, .7, .2, 1); }
@media (prefers-reduced-motion: reduce) {
  .rise, .rise.is-in { opacity: 1; transform: none; transition: none; }
  .beat { opacity: 1; transform: none; transition: none; }
  .hero__cue i { animation: none; }
}

/* ============================================================ PHONE POLISH
   Applied on top of the fluid layout. The page was fluid but not mobile-
   native: desktop-sized rhythm, inline button rows that wrapped awkwardly,
   and tap targets under the 44px guideline.
   ========================================================================= */
@media (max-width: 34em) {
  :root {
    --gutter: 1.15rem;
    --step: 3.25rem;
    --measure: 100%;
  }

  /* Full-width stacked CTAs are the phone convention and they double the
     tap area of the primary action. */
  .btn-row { flex-direction: column; align-items: stretch; gap: .6rem; }
  .btn-row .btn { justify-content: center; padding-block: .95rem; }
  .btn { min-height: 44px; }

  .h1 { font-size: clamp(2rem, 8.4vw, 2.8rem); }
  .h2 { font-size: clamp(1.55rem, 6.8vw, 2.2rem); }
  .h3 { font-size: 1.2rem; }
  .lede { font-size: 1.0625rem; }
  body { font-size: 1.0625rem; }

  /* Cards and grids: one column, edge to edge, no cramped side-by-side. */
  .cols { gap: 1.75rem; margin-top: 2.25rem; }
  .stat-row { grid-template-columns: 1fr; margin-top: 2rem; }
  .stat { padding: 1.4rem 1.15rem; }
  .talks { grid-template-columns: 1fr; margin-top: 2rem; }
  .talk { padding: 1.5rem 1.15rem; }
  .field-grid { grid-template-columns: 1fr; }

  /* iOS zooms the page when a focused input is under 16px. */
  .field input, .field select, .field textarea { font-size: 1rem; }

  .book { gap: 2rem; }
  .book__cover { max-width: 15rem; margin-inline: auto; }
  .formats li { flex-wrap: wrap; gap: .35rem .75rem; }
  .formats b { min-width: 5.5rem; }

  .proof { padding: 1.4rem 1.15rem; border-radius: 10px; }
  .pull blockquote { font-size: 1.25rem; }
  .facts { gap: .4rem; }
  .facts li { font-size: .78125rem; padding: .4rem .7rem; }

  .foot__grid { gap: 1.75rem; }
  .author__card { padding-left: 1.15rem; }
}

/* ------------------------------------------------------------ debug hud */
.fps {
  position: fixed; right: .6rem; bottom: .6rem; z-index: 90;
  font-family: var(--mono); font-size: .6875rem; line-height: 1.5;
  background: rgba(0, 0, 0, .88); color: #7dffa8; border: 1px solid #23402c;
  padding: .5rem .65rem; border-radius: 6px; white-space: pre; display: none;
  max-width: calc(100vw - 1.2rem); overflow: auto;
  -webkit-user-select: all; user-select: all;   /* tap-and-hold to copy on a phone */
}
.fps.is-on { display: block; }
@media (max-width: 34em) {
  /* On a phone the corner is unreadable, so pin it across the bottom. */
  .fps { left: .6rem; right: .6rem; bottom: .6rem; font-size: .625rem; }
}