/* ===========================================================================
   ScholarBot AI — landing page
   Aesthetic: printed editorial. Warm paper, walnut ink, aged gold.
   Motif: footnote markers — the same [n] badges the product uses for citations.
   Tokens mirror scholarbot-web/tailwind.config.js so the page and the app
   feel like one object.
   ======================================================================== */

:root {
  --paper:        #FAF6F0;
  --paper-warm:   #F5EFEB;
  --paper-raised: #FDFCFA;

  --ink:          #1C1814;
  --ink-body:     #3D3632;
  --ink-muted:    #8A7F74;
  --ink-subtle:   #B5A99E;

  --walnut:       #4A3728;
  --walnut-dark:  #2C2417;
  --walnut-muted: #7A6250;

  --gold:         #8B6914;
  --gold-light:   #C49A3A;
  --teal:         #4A7C6F;

  --line:         #EADFCF;
  --line-strong:  #C5BAB0;

  --shadow-sm: 0 1px 3px rgba(44,36,23,.05), 0 1px 2px rgba(44,36,23,.03);
  --shadow-md: 0 2px 10px rgba(44,36,23,.07), 0 1px 3px rgba(44,36,23,.04);
  --shadow-lg: 0 18px 50px -24px rgba(44,36,23,.35), 0 2px 8px rgba(44,36,23,.06);

  --serif: "DM Serif Display", Georgia, serif;
  --sans:  "DM Sans", system-ui, sans-serif;
  --mono:  "JetBrains Mono", ui-monospace, monospace;

  --gutter: clamp(1.25rem, 5vw, 5.5rem);
  --measure: 62ch;
  --ease: cubic-bezier(.2, .8, .2, 1);
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink-body);
  font-family: var(--sans);
  font-size: clamp(15px, .55vw + 13.6px, 17px);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }

a { color: inherit; }

::selection { background: var(--gold-light); color: var(--walnut-dark); }

:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--walnut-dark); color: var(--paper);
  padding: .75rem 1.25rem; font-size: .85rem;
}
.skip:focus { left: 0; }

/* --- paper grain: keeps large flat areas from looking like flat screens --- */
.grain {
  position: fixed; inset: 0; z-index: 900; pointer-events: none;
  opacity: .038; mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* --- reading progress, drawn as a margin rule rather than a bar --- */
.rule-progress {
  position: fixed; top: 0; left: 0; right: 0; height: 2px; z-index: 80;
  background: transparent; pointer-events: none;
}
.rule-progress span {
  display: block; height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--walnut), var(--gold-light));
}

/* ============================== typography ============================== */

.display {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(2.9rem, 7.6vw, 6.4rem);
  line-height: .96;
  letter-spacing: -.02em;
  color: var(--ink);
  margin: .5rem 0 1.5rem;
}
.display em { font-style: italic; color: var(--walnut); }
/* keeps the footnote marker glued to the word it annotates on narrow screens */
.nowrap { white-space: nowrap; }

/* the mask needs room for descenders ("j" in Belajar) — the negative margin
   pays the padding back so line spacing is unchanged */
.line { display: block; overflow: hidden; padding-bottom: .18em; margin-bottom: -.18em; }
.line > span { display: block; }

.h2 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.9rem, 3.4vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -.015em;
  color: var(--ink);
  margin: .35rem 0 1rem;
  text-wrap: balance;
}
.h2--light { color: var(--paper); }

.eyebrow {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--walnut-muted);
  margin: 0;
}
.eyebrow__sep { color: var(--line-strong); padding: 0 .35em; }
.eyebrow--light { color: var(--gold-light); }

.lede {
  font-size: clamp(1.05rem, 1.15vw + .8rem, 1.35rem);
  line-height: 1.55;
  color: var(--ink-body);
  max-width: 34ch;
  margin: 0 0 2rem;
}
.lede strong { color: var(--ink); font-weight: 500; }

.body { max-width: var(--measure); margin: 0 0 1.1rem; }
.body--light { color: #D9CFC2; }

/* --- footnote marker: the page-wide echo of the product's [n] badge --- */
.fn {
  display: inline-flex; align-items: center; justify-content: center;
  vertical-align: super;
  min-width: 1.45em; height: 1.45em; padding: 0 .35em;
  margin-left: .22em;
  border: 1px solid rgba(74,55,40,.25);
  border-radius: 999px;
  background: rgba(74,55,40,.08);
  color: var(--walnut);
  font-family: var(--mono);
  font-size: .3em;
  font-weight: 500;
  line-height: 1;
  text-decoration: none;
  transition: background .25s var(--ease), color .25s var(--ease), transform .25s var(--ease);
}
.fn:hover { background: var(--walnut); color: var(--paper-raised); transform: translateY(-2px); }
.fn--static { font-size: .62rem; vertical-align: baseline; margin: 0 .5em 0 0; }

/* ================================= nav ================================= */

.nav {
  position: sticky; top: 0; z-index: 70;
  display: flex; align-items: center; gap: 2rem;
  padding: .85rem var(--gutter);
  background: color-mix(in srgb, var(--paper) 82%, transparent);
  backdrop-filter: blur(12px) saturate(1.1);
  border-bottom: 1px solid transparent;
  transition: border-color .3s var(--ease), background .3s var(--ease);
}
.nav.is-stuck { border-bottom-color: var(--line); }

.nav__brand {
  display: flex; align-items: center; gap: .6rem;
  font-family: var(--serif); font-size: 1.15rem; color: var(--ink);
  text-decoration: none; margin-right: auto;
}
.nav__brand img { width: 34px; height: auto; border-radius: 8px; }
.nav__dim { color: var(--walnut-muted); }

.nav__links { display: flex; gap: 1.6rem; }
.nav__links a {
  font-size: .86rem; color: var(--ink-body); text-decoration: none;
  position: relative; padding-bottom: 2px;
}
.nav__links a::after {
  content: ''; position: absolute; left: 0; bottom: 0; height: 1px; width: 100%;
  background: var(--walnut); transform: scaleX(0); transform-origin: right;
  transition: transform .35s var(--ease);
}
.nav__links a:hover::after { transform: scaleX(1); transform-origin: left; }

/* ================================ buttons ============================== */

.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  padding: .72rem 1.35rem;
  border-radius: 999px;
  font-size: .88rem; font-weight: 500; text-decoration: none;
  transition: transform .25s var(--ease), background .25s var(--ease),
              color .25s var(--ease), border-color .25s var(--ease), box-shadow .25s var(--ease);
}
.btn:hover { transform: translateY(-2px); }

.btn--solid {
  background: var(--walnut); color: var(--paper-raised);
  box-shadow: var(--shadow-md);
}
.btn--solid:hover { background: var(--walnut-dark); box-shadow: var(--shadow-lg); }

.btn--quiet {
  position: relative;
  color: var(--ink-body);
  padding-left: .25rem; padding-right: .25rem;
}
.btn--quiet::after {
  content: ''; position: absolute; left: .25rem; right: .25rem; bottom: .45rem;
  height: 1px; background: var(--line-strong);
  transform-origin: right; transition: transform .4s var(--ease), background .3s var(--ease);
}
.btn--quiet:hover { color: var(--ink); transform: none; }
.btn--quiet:hover::after { background: var(--walnut); animation: underline .5s var(--ease); }

@keyframes underline {
  0%   { transform: scaleX(1); transform-origin: right; }
  49%  { transform: scaleX(0); transform-origin: right; }
  50%  { transform: scaleX(0); transform-origin: left; }
  100% { transform: scaleX(1); transform-origin: left; }
}

.btn--ghost {
  border: 1px solid var(--line-strong); color: var(--ink-body);
  padding: .5rem 1rem; font-size: .82rem;
}
.btn--ghost:hover { border-color: var(--walnut); color: var(--ink); }

/* ================================= hero ================================ */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: center;
  padding: clamp(3.5rem, 8vw, 7.5rem) var(--gutter) clamp(3rem, 6vw, 5.5rem);
  position: relative;
}
/* faint ruled paper behind the hero, fading out — texture, not decoration */
.hero::before {
  content: ''; position: absolute; inset: 0; z-index: -1;
  background-image: repeating-linear-gradient(
      to bottom, transparent, transparent 37px, var(--line) 37px, var(--line) 38px);
  -webkit-mask-image: radial-gradient(120% 80% at 70% 30%, #000 10%, transparent 68%);
          mask-image: radial-gradient(120% 80% at 70% 30%, #000 10%, transparent 68%);
  opacity: .5;
}

.hero__cta { display: flex; flex-wrap: wrap; align-items: center; gap: 1.5rem; }

.hero__note {
  margin: 2.25rem 0 0;
  font-family: var(--mono); font-size: .74rem; letter-spacing: .04em;
  color: var(--ink-subtle);
}

.hero__caption {
  margin: 1rem 0 0; text-align: center;
  font-size: .78rem; color: var(--ink-muted);
}

/* ---------------------------- chat demo card --------------------------- */

.chat {
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  transform: rotate(-.5deg);
}

.chat__bar {
  display: flex; align-items: center; gap: .45rem;
  padding: .7rem .95rem;
  background: var(--paper-warm);
  border-bottom: 1px solid var(--line);
}
.dot { width: 9px; height: 9px; border-radius: 50%; background: var(--line-strong); }
.chat__file {
  margin-left: auto;
  font-family: var(--mono); font-size: .66rem; color: var(--walnut-muted);
  display: inline-flex; align-items: center; gap: .4rem;
}
.chat__file::before {
  content: ''; width: 6px; height: 6px; border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 0 color-mix(in srgb, var(--teal) 60%, transparent);
  animation: pulse 2.6s ease-out infinite;
}

.chat__body { padding: 1.15rem; display: flex; flex-direction: column; gap: .85rem; min-height: 310px; }

.bubble {
  padding: .8rem 1rem;
  border-radius: 14px;
  font-size: .88rem;
  line-height: 1.6;
  transition: opacity .5s var(--ease), transform .5s var(--ease);
}
.js .bubble { opacity: 0; transform: translateY(10px); }
.js .bubble.is-in { opacity: 1; transform: none; }

.bubble--user {
  align-self: flex-end; max-width: 78%;
  background: var(--paper-warm);
  border: 1px solid var(--line);
  color: var(--ink-body);
}
.bubble--bot {
  align-self: flex-start; max-width: 92%;
  background: linear-gradient(180deg, #FFFDFB, #F8F3EC);
  border: 1px solid var(--line);
  font-family: var(--serif); font-size: .95rem; line-height: 1.55;
  color: var(--ink-body);
}
.bubble--bot .answer { margin: 0; min-height: 1em; }

.typing { display: none; gap: 4px; padding: .2rem 0; }
.js .typing { display: inline-flex; }
.typing i {
  width: 6px; height: 6px; border-radius: 50%; background: var(--ink-subtle);
  animation: blink 1.1s infinite ease-in-out;
}
.typing i:nth-child(2) { animation-delay: .16s; }
.typing i:nth-child(3) { animation-delay: .32s; }
.typing.is-done { display: none; }

/* the inline citation badge, matching the React component in the app */
.srcbadge {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 16px; height: 16px; padding: 0 4px;
  border-radius: 999px;
  border: 1px solid rgba(74,55,40,.2);
  background: rgba(74,55,40,.1);
  color: var(--walnut);
  font-family: var(--sans); font-size: .58rem; font-weight: 700; line-height: 1;
  vertical-align: super;
  cursor: pointer;
  transition: background .2s var(--ease), color .2s var(--ease), transform .2s var(--ease);
}
.srcbadge:hover, .srcbadge.is-active { background: var(--walnut); color: var(--paper-raised); }
.srcbadge--inline { cursor: default; margin: 0 .1em; }
/* on the dark section the badge needs real luminance to stay legible */
.srcbadge--light { border-color: rgba(240,231,216,.55); background: rgba(240,231,216,.26); color: #FBF5EC; }

.answer .srcbadge { animation: pop .45s var(--ease) both; }

.srccard {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--paper-warm);
  padding: .8rem .9rem;
  transition: opacity .55s var(--ease), transform .55s var(--ease), border-color .3s var(--ease), box-shadow .3s var(--ease);
}
.js .srccard { opacity: 0; transform: translateY(12px); }
.js .srccard.is-in { opacity: 1; transform: none; }
.srccard.is-lit { border-color: var(--walnut); box-shadow: 0 0 0 3px rgba(74,55,40,.1); }

.srccard__head { display: flex; align-items: center; gap: .5rem; margin-bottom: .45rem; flex-wrap: wrap; }
.srccard__head .srcbadge { vertical-align: baseline; background: var(--walnut); color: var(--paper-raised); border-color: var(--walnut); cursor: default; }
.srccard__name { font-size: .72rem; font-weight: 700; color: var(--ink); }
.srccard__meta { font-family: var(--mono); font-size: .62rem; color: var(--ink-muted); margin-left: auto; }
.srccard__quote {
  margin: 0; font-family: var(--mono); font-size: .66rem; line-height: 1.75;
  color: var(--ink-body);
  padding: .55rem .65rem;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.chat__replay {
  display: flex; align-items: center; gap: .4rem;
  margin: 0 0 0 auto; padding: .55rem .95rem;
  background: none; border: 0; border-top: 1px solid var(--line);
  width: 100%; justify-content: center;
  font-family: var(--mono); font-size: .66rem; letter-spacing: .06em;
  color: var(--ink-muted); cursor: pointer;
  transition: color .25s var(--ease), background .25s var(--ease);
}
.chat__replay:hover { color: var(--walnut); background: var(--paper-warm); }

/* =============================== metrics =============================== */

.metrics {
  padding: clamp(2rem, 4vw, 3rem) var(--gutter);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper-warm) 55%, var(--paper));
}
.metrics dl {
  margin: 0; display: grid; gap: 1.5rem clamp(1rem, 4vw, 3rem);
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
}
.metric dt {
  order: 2;
  font-family: var(--mono); font-size: .68rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-muted);
}
.metric dd {
  order: 1; margin: 0;
  font-family: var(--serif); font-size: clamp(2.4rem, 4vw, 3.4rem); line-height: 1;
  color: var(--walnut);
}
.metric { display: flex; flex-direction: column; gap: .35rem; }

/* ============================ split sections =========================== */

.split {
  display: grid;
  grid-template-columns: minmax(0, .95fr) minmax(0, 1.05fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center;
  padding: clamp(4rem, 9vw, 8rem) var(--gutter);
}
.split--flip .split__media { order: 2; }

.split__media { margin: 0; position: relative; }
.split__media img {
  width: 100%; height: clamp(320px, 46vw, 560px); object-fit: cover;
  border-radius: 4px;
  box-shadow: var(--shadow-lg);
  will-change: transform;
}
.split__media figcaption {
  margin-top: .6rem;
  font-family: var(--mono); font-size: .62rem; letter-spacing: .06em;
  color: var(--ink-subtle);
}

.claims { list-style: none; padding: 0; margin: 2rem 0 0; display: grid; gap: 1.15rem; }
.claims li {
  display: grid; grid-template-columns: auto 1fr; gap: 1rem; align-items: baseline;
  padding-top: 1.15rem; border-top: 1px solid var(--line);
  max-width: var(--measure);
}
.claims__n { font-family: var(--mono); font-size: .72rem; color: var(--gold); letter-spacing: .08em; }
.claims b { color: var(--ink); font-weight: 700; }

/* =============================== sections ============================== */

.section { padding: clamp(4rem, 9vw, 8rem) var(--gutter); }
.section--rule { border-top: 1px solid var(--line); }
.section__head { max-width: 46ch; margin-bottom: clamp(2.5rem, 5vw, 4rem); }

/* ------------------------------- features ------------------------------ */

.features {
  list-style: none; margin: 0; padding: 0;
  display: grid; gap: 1px;
  /* six cards: two tidy rows of three on desktop, never a half-empty row */
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 6px;
  overflow: hidden;
}
.feature {
  counter-increment: feat;
  position: relative;
  background: var(--paper);
  padding: 2rem 1.75rem 2.1rem;
  transition: background .35s var(--ease);
}
.feature::before {
  content: counter(feat, decimal-leading-zero);
  position: absolute; top: 1.5rem; right: 1.6rem;
  font-family: var(--mono); font-size: .68rem; color: var(--ink-subtle);
  transition: color .35s var(--ease);
}
.feature:hover { background: var(--paper-raised); }
.feature:hover::before { color: var(--gold); }
.features { counter-reset: feat; }

.feature__icon {
  width: 30px; height: 30px; color: var(--walnut);
  margin-bottom: 1.1rem;
  transition: transform .4s var(--ease), color .35s var(--ease);
}
.feature:hover .feature__icon { transform: translateY(-3px) rotate(-4deg); color: var(--gold); }

.feature h3 {
  font-family: var(--serif); font-weight: 400; font-size: 1.32rem;
  color: var(--ink); margin: 0 0 .5rem;
}
.feature p { margin: 0; font-size: .92rem; color: var(--ink-body); }

/* ------------------------------- pipeline ------------------------------ */

.pipeline {
  list-style: none; margin: 0; padding: 0;
  display: grid; gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  position: relative;
}
.pipeline::before {
  content: ''; position: absolute; top: 19px; left: 0;
  height: 1px; width: var(--pipe, 0%);
  background: linear-gradient(90deg, var(--walnut), var(--gold-light));
  transition: width 1.6s var(--ease);
}
.step { position: relative; padding-top: 3.25rem; }
.step__n {
  position: absolute; top: 0; left: 0;
  display: grid; place-items: center;
  width: 38px; height: 38px; border-radius: 50%;
  background: var(--paper); border: 1px solid var(--line-strong);
  font-family: var(--mono); font-size: .82rem; color: var(--walnut);
  transition: background .4s var(--ease), color .4s var(--ease), border-color .4s var(--ease);
}
.step.is-in .step__n { background: var(--walnut); border-color: var(--walnut); color: var(--paper-raised); }
.step h3 { font-family: var(--serif); font-weight: 400; font-size: 1.2rem; color: var(--ink); margin: 0 0 .35rem; }
.step p { margin: 0; font-size: .88rem; color: var(--ink-body); }
.step code { font-family: var(--mono); font-size: .8em; color: var(--walnut); }

.pipeline__note {
  margin: 3rem 0 0; padding: 1.4rem 1.6rem;
  background: var(--paper-warm); border: 1px solid var(--line); border-radius: 6px;
  max-width: 70ch; font-size: .92rem;
}

/* ------------------------- citation spotlight -------------------------- */

.cite {
  background: var(--walnut-dark);
  color: #D9CFC2;
  padding: clamp(4.5rem, 10vw, 9rem) var(--gutter);
  position: relative;
  overflow: hidden;
}
.cite::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(60% 60% at 80% 0%, rgba(196,154,58,.16), transparent 70%);
}
.cite__inner { position: relative; max-width: 72ch; }
.cite__list { list-style: none; padding: 0; margin: 2.25rem 0 0; display: grid; gap: 1rem; }
.cite__list li {
  padding-left: 1.6rem; position: relative; font-size: .95rem; color: #CFC3B4;
  max-width: var(--measure);
}
.cite__list li::before {
  content: ''; position: absolute; left: 0; top: .62em;
  width: 7px; height: 7px; border-radius: 50%; background: var(--gold-light);
}
.cite__list b { color: var(--paper); font-weight: 700; }

/* -------------------------------- stack -------------------------------- */

.stack {
  list-style: none; margin: 0; padding: 0;
  display: flex; flex-wrap: wrap; gap: .75rem;
}
.stack li {
  display: inline-flex; align-items: center; gap: .65rem;
  padding: .7rem 1.15rem .7rem .8rem;
  border: 1px solid var(--line); border-radius: 999px;
  background: var(--paper-raised);
  font-size: .86rem; color: var(--ink-body);
  transition: transform .3s var(--ease), border-color .3s var(--ease), box-shadow .3s var(--ease);
}
.stack li:hover { transform: translateY(-3px); border-color: var(--line-strong); box-shadow: var(--shadow-md); }
.stack img { width: 22px; height: 22px; }

/* ================================ footer =============================== */

.footer {
  border-top: 1px solid var(--line);
  padding: clamp(3rem, 6vw, 5rem) var(--gutter) 3rem;
  background: color-mix(in srgb, var(--paper-warm) 45%, var(--paper));
}
.footer__top {
  display: flex; flex-wrap: wrap; gap: 1.5rem; justify-content: space-between;
  align-items: flex-end; padding-bottom: 2rem; border-bottom: 1px solid var(--line);
}
.footer__mark { font-family: var(--serif); font-size: 1.6rem; color: var(--ink); margin: 0 0 .2rem; }
.footer__by { margin: 0; font-size: .88rem; color: var(--ink-muted); }
.footer__links { list-style: none; display: flex; gap: 1.5rem; margin: 0; padding: 0; }
.footer__links a { font-size: .88rem; text-decoration: none; border-bottom: 1px solid var(--line-strong); padding-bottom: 2px; }
.footer__links a:hover { border-color: var(--walnut); }

.footer__notes { margin-top: 2rem; }
.footer__noteshead {
  font-family: var(--mono); font-size: .68rem; letter-spacing: .16em;
  text-transform: uppercase; color: var(--ink-subtle); margin: 0 0 .85rem;
}
.footer__notes ol { list-style: none; margin: 0; padding: 0; display: grid; gap: .55rem; max-width: 78ch; }
.footer__notes li { font-size: .8rem; color: var(--ink-muted); line-height: 1.6; }
.footer__notes a { color: var(--walnut-muted); }

/* ============================== animation ============================== */

@keyframes rise   { from { transform: translateY(125%); } to { transform: translateY(0); } }
@keyframes fadeUp { from { opacity: 0; transform: translateY(18px); } to { opacity: 1; transform: none; } }
@keyframes blink  { 0%, 60%, 100% { opacity: .25; transform: translateY(0); } 30% { opacity: 1; transform: translateY(-3px); } }
@keyframes pop    { 0% { opacity: 0; transform: scale(.4); } 60% { transform: scale(1.18); } 100% { opacity: 1; transform: scale(1); } }
@keyframes pulse  {
  0%   { box-shadow: 0 0 0 0 color-mix(in srgb, var(--teal) 55%, transparent); }
  70%  { box-shadow: 0 0 0 7px transparent; }
  100% { box-shadow: 0 0 0 0 transparent; }
}

/* Progressive enhancement: main.js adds .js to <html> before first paint.
   Without JS — or if the script fails — every section stays fully visible
   instead of the page looking empty. */
.js .display .line > span { animation: rise 1.05s var(--ease) both; }
.js .display .line:nth-child(1) > span { animation-delay: .06s; }
.js .display .line:nth-child(2) > span { animation-delay: .19s; }

/* everything marked .reveal waits for the observer in main.js */
.js .reveal { opacity: 0; }
.js .reveal.is-in { animation: fadeUp .85s var(--ease) both; }

.hero .reveal.is-in { animation-delay: calc(var(--i, 0) * 90ms + 320ms); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
  .js .reveal { opacity: 1; }
  .bubble, .srccard { opacity: 1; transform: none; }
  .split__media img { transform: none !important; }
}

/* ============================== responsive ============================= */

@media (min-width: 1100px) {
  .features { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 1000px) {
  .hero { grid-template-columns: 1fr; }
  .hero__demo { max-width: 560px; }
  .split, .split--flip { grid-template-columns: 1fr; }
  .split--flip .split__media { order: 0; }
  .lede { max-width: 48ch; }
}

@media (max-width: 720px) {
  .nav__links { display: none; }
  .chat { transform: none; }
  .split__media img { height: clamp(260px, 60vw, 380px); }
  .footer__top { align-items: flex-start; }
}