/* =========================================================================
   Mineração Lapa Vermelha — Design System "Estratigrafia"
   Paleta de calcário + óxido de ferro (vermelha) + basalto.
   Tipografia engenheirada: Archivo / IBM Plex Sans / IBM Plex Mono.
   ========================================================================= */

:root {
  /* Cores — rocha */
  --limestone:    #EAE5DA;  /* fundo claro (calcário) */
  --limestone-2:  #F3EFE7;  /* cards / superfícies claras */
  --stone:        #D7D0C2;  /* bordas / hairlines */
  --basalt:       #16130E;  /* fundo escuro (basalto) */
  --basalt-2:     #211C15;  /* superfície escura */
  --ink:          #16130E;  /* texto sobre claro */
  --slate:        #6E665A;  /* texto secundário */
  --oxide:        #A62A1B;  /* acento primário (óxido de ferro) */
  --oxide-bright: #C63A26;  /* acento hover / brilho */
  --ochre:        #BE9550;  /* acento secundário (pó de cal) */
  --paper-on-dark:#EFE9DD;  /* texto sobre escuro */
  --slate-on-dark:#A99F8E;  /* texto secundário sobre escuro */

  /* Tipos */
  --font-display: 'Archivo', system-ui, sans-serif;
  --font-body:    'IBM Plex Sans', system-ui, sans-serif;
  --font-mono:    'IBM Plex Mono', ui-monospace, monospace;

  /* Escala tipográfica */
  --fs-hero:    clamp(2.7rem, 7.2vw, 6rem);
  --fs-h2:      clamp(1.9rem, 4vw, 3.25rem);
  --fs-h3:      clamp(1.2rem, 2vw, 1.55rem);
  --fs-body:    1.0625rem;
  --fs-small:   0.875rem;
  --fs-eyebrow: 0.72rem;

  /* Layout */
  --maxw: 1200px;
  --gutter: clamp(1.25rem, 5vw, 4rem);
  --radius: 3px;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* --------------------------------------------------------------------- base */
* { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}

body {
  margin: 0;
  background: var(--limestone);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: -0.02em;
  margin: 0;
  text-wrap: balance;
}

::selection { background: var(--oxide); color: var(--limestone-2); }

:focus-visible { outline: 2.5px solid var(--oxide); outline-offset: 3px; border-radius: 2px; }

/* --------------------------------------------------------------- utilities */
.container { max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--oxide);
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  margin: 0 0 1.1rem;
  font-weight: 500;
}
.eyebrow::before {
  content: "";
  width: 26px; height: 1.5px;
  background: var(--oxide);
  display: inline-block;
}
.section { padding-block: clamp(4rem, 9vw, 8rem); position: relative; }
.section__lead { max-width: 62ch; color: var(--slate); font-size: 1.15rem; }
.section-dark { background: var(--basalt); color: var(--paper-on-dark); }
.section-dark .eyebrow { color: var(--ochre); }
.section-dark .eyebrow::before { background: var(--ochre); }
.section-dark .section__lead { color: var(--slate-on-dark); }

/* Reveal on scroll */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.is-in { opacity: 1; transform: none; }

/* Botões */
.btn {
  --bg: var(--oxide); --fg: var(--limestone-2);
  display: inline-flex; align-items: center; gap: .55rem;
  background: var(--bg); color: var(--fg);
  font-family: var(--font-mono); font-size: .82rem; font-weight: 500;
  letter-spacing: .06em; text-transform: uppercase;
  padding: .85rem 1.4rem; border: 0; border-radius: var(--radius);
  cursor: pointer; white-space: nowrap;
  transition: background .25s var(--ease), transform .15s var(--ease);
}
.btn:hover { background: var(--oxide-bright); }
.btn:active { transform: translateY(1px); }
.btn--ghost {
  background: transparent; color: var(--ink);
  box-shadow: inset 0 0 0 1.5px var(--stone);
}
.section-dark .btn--ghost { color: var(--paper-on-dark); box-shadow: inset 0 0 0 1.5px rgba(239,233,221,.28); }
.btn--ghost:hover { background: transparent; box-shadow: inset 0 0 0 1.5px var(--oxide); color: var(--oxide); }

/* ==================================================================== header */
.site-header {
  position: sticky; top: 0; z-index: 60;
  background: color-mix(in srgb, var(--limestone) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s, background .3s;
}
.site-header.is-stuck { border-bottom-color: var(--stone); }
.nav {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1.5rem; height: 74px;
}
.brand { display: flex; align-items: center; gap: .7rem; }
.brand img { height: 38px; width: auto; }
.brand__txt { display: flex; flex-direction: column; line-height: 1; }
.brand__name { font-family: var(--font-display); font-weight: 800; font-size: .98rem; letter-spacing: -.01em; }
.brand__sub { font-family: var(--font-mono); font-size: .58rem; letter-spacing: .2em; text-transform: uppercase; color: var(--slate); margin-top: 3px; }

.nav__links { display: flex; align-items: center; gap: 1.6rem; list-style: none; margin: 0; padding: 0; }
.nav__links a {
  font-size: .84rem; font-weight: 500; letter-spacing: .01em; color: var(--slate);
  position: relative; padding-block: .4rem; transition: color .2s;
}
.nav__links a:hover { color: var(--ink); }
.nav__links a::after {
  content: ""; position: absolute; left: 0; bottom: -2px; height: 1.5px; width: 0;
  background: var(--oxide); transition: width .25s var(--ease);
}
.nav__links a:hover::after { width: 100%; }

.nav__cta { display: flex; align-items: center; gap: .8rem; }
.nav__toggle {
  display: none; background: none; border: 0; cursor: pointer;
  width: 44px; height: 44px; padding: 10px; color: var(--ink);
}
.nav__toggle span { display: block; height: 2px; background: currentColor; margin: 5px 0; transition: .3s var(--ease); }

/* ===================================================================== hero */
.hero {
  position: relative; background: var(--basalt); color: var(--paper-on-dark);
  min-height: min(92vh, 860px);
  display: flex; align-items: flex-end;
  overflow: hidden;
}
.hero__bg {
  position: absolute; inset: 0; z-index: 0;
  background-image: url('../img/hero-1.jpg');
  background-size: cover; background-position: center;
  filter: grayscale(.35) contrast(1.05);
}
.hero__bg::after {
  content: ""; position: absolute; inset: 0;
  background:
    linear-gradient(180deg, rgba(22,19,14,.55) 0%, rgba(22,19,14,.35) 40%, rgba(22,19,14,.92) 100%),
    linear-gradient(90deg, rgba(166,42,27,.28) 0%, transparent 55%);
}
.hero .container { position: relative; z-index: 1; padding-block: clamp(3rem, 8vw, 6rem); width: 100%; }
.hero__eyebrow {
  font-family: var(--font-mono); font-size: var(--fs-eyebrow); letter-spacing: .22em; text-transform: uppercase;
  color: var(--ochre); margin: 0 0 1.4rem; display: flex; align-items: center; gap: .7rem;
}
.hero__eyebrow::before { content: ""; width: 34px; height: 1.5px; background: var(--ochre); }
.hero h1 {
  font-size: var(--fs-hero); max-width: 15ch; margin-bottom: 1.5rem;
  letter-spacing: -.03em;
}
.hero h1 em { font-style: normal; color: var(--oxide-bright); }
.hero__sub { max-width: 52ch; font-size: 1.2rem; color: var(--paper-on-dark); opacity: .88; margin-bottom: 2.4rem; }
.hero__actions { display: flex; flex-wrap: wrap; gap: .9rem; }

/* Faixa de dados do hero (assinatura de dados) */
.datastrip {
  position: relative; z-index: 1; background: var(--basalt-2);
  border-top: 1px solid rgba(239,233,221,.12);
}
.datastrip__grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
}
.datastrip__cell {
  padding: 1.6rem var(--gutter); border-left: 1px solid rgba(239,233,221,.1);
}
.datastrip__cell:first-child { border-left: 0; }
.datastrip__num { font-family: var(--font-mono); font-size: clamp(1.4rem, 2.6vw, 2rem); font-weight: 600; color: var(--paper-on-dark); letter-spacing: -.02em; }
.datastrip__num span { color: var(--oxide-bright); }
.datastrip__label { font-size: .74rem; letter-spacing: .04em; color: var(--slate-on-dark); text-transform: uppercase; margin-top: .3rem; font-family: var(--font-mono); }

/* ============================================================ empresa/história */
.split { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(2rem, 5vw, 4.5rem); align-items: start; }
.prose p { margin: 0 0 1.1rem; color: var(--slate); }
.prose p:first-of-type { color: var(--ink); font-size: 1.18rem; }

/* Timeline (sequência real de marcos) */
.timeline { list-style: none; margin: 2.2rem 0 0; padding: 0; border-left: 2px solid var(--stone); }
.timeline li { position: relative; padding: 0 0 1.7rem 1.7rem; }
.timeline li::before {
  content: ""; position: absolute; left: -7px; top: 4px; width: 12px; height: 12px;
  background: var(--limestone); border: 2.5px solid var(--oxide); border-radius: 50%;
}
.timeline .year { font-family: var(--font-mono); font-weight: 600; color: var(--oxide); font-size: .95rem; letter-spacing: .02em; }
.timeline .ev { display: block; color: var(--slate); font-size: .98rem; margin-top: .15rem; }

.media-frame { position: relative; }
.media-frame img { border-radius: var(--radius); width: 100%; height: 100%; object-fit: cover; }
.media-frame::before {
  content: ""; position: absolute; inset: -10px -10px auto auto; width: 60px; height: 60px;
  border-top: 2px solid var(--oxide); border-right: 2px solid var(--oxide);
}

/* =============================================== estrutura / capacidades (dados) */
.capgrid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 0; margin-top: 3rem; border-top: 1px solid var(--stone); border-left: 1px solid var(--stone); }
.cap {
  padding: 1.9rem 1.6rem; border-right: 1px solid var(--stone); border-bottom: 1px solid var(--stone);
  background: var(--limestone-2); transition: background .3s;
}
.cap:hover { background: #fff; }
.cap__num { font-family: var(--font-mono); font-size: clamp(1.7rem, 3vw, 2.4rem); font-weight: 600; letter-spacing: -.03em; color: var(--ink); }
.cap__num small { font-size: .9rem; color: var(--oxide); font-weight: 600; }
.cap__label { font-size: .86rem; color: var(--slate); margin-top: .5rem; }
.cap__tag { font-family: var(--font-mono); font-size: .64rem; letter-spacing: .16em; text-transform: uppercase; color: var(--ochre); display: block; margin-bottom: .8rem; }

/* Logística */
.duo { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(1.5rem,4vw,3rem); margin-top: 2.5rem; }
.duo__card { padding: 2rem; background: var(--limestone-2); border: 1px solid var(--stone); border-radius: var(--radius); border-top: 3px solid var(--oxide); }
.duo__card h3 { margin-bottom: .8rem; font-size: var(--fs-h3); }
.duo__card p { margin: 0; color: var(--slate); }

/* ======================================== produtos — PLACAS DE ENSAIO (assinatura) */
.assays { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(1.5rem, 4vw, 2.5rem); margin-top: 3rem; }
.assay {
  background: var(--limestone-2); border: 1px solid var(--stone); border-radius: var(--radius);
  overflow: hidden; display: flex; flex-direction: column;
}
.assay__head {
  display: flex; align-items: baseline; justify-content: space-between; gap: 1rem;
  padding: 1.3rem 1.5rem; background: var(--basalt); color: var(--paper-on-dark);
}
.assay__head h3 { font-size: 1.35rem; color: var(--paper-on-dark); }
.assay__code { font-family: var(--font-mono); font-size: .68rem; letter-spacing: .12em; color: var(--ochre); text-transform: uppercase; }
.assay__body { padding: 1.4rem 1.5rem 1.7rem; }
.assay__subtitle {
  font-family: var(--font-mono); font-size: .68rem; letter-spacing: .16em; text-transform: uppercase;
  color: var(--oxide); margin: 1.2rem 0 .7rem; padding-bottom: .4rem; border-bottom: 1px solid var(--stone);
}
.assay__subtitle:first-child { margin-top: 0; }
.spec { list-style: none; margin: 0; padding: 0; }
.spec li {
  display: flex; justify-content: space-between; gap: 1rem;
  font-size: .9rem; padding: .42rem 0; border-bottom: 1px dashed var(--stone);
}
.spec li:last-child { border-bottom: 0; }
.spec .k { color: var(--slate); }
.spec .v { font-family: var(--font-mono); font-weight: 500; color: var(--ink); text-align: right; white-space: nowrap; }
.assay__loads { margin-top: 1.3rem; display: flex; flex-wrap: wrap; gap: .5rem; }
.chip {
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .04em;
  padding: .35rem .7rem; border: 1px solid var(--stone); border-radius: 999px; color: var(--slate);
}

/* Qualidade */
.quality { display: grid; grid-template-columns: .8fr 1.2fr; gap: clamp(2rem,5vw,4rem); align-items: center; }
.seal {
  aspect-ratio: 1; display: grid; place-content: center; text-align: center;
  border: 2px solid var(--oxide); border-radius: 50%; max-width: 260px; margin-inline: auto;
  padding: 2rem;
}
.seal__iso { font-family: var(--font-display); font-weight: 800; font-size: clamp(2rem,4vw,3rem); color: var(--oxide); letter-spacing: -.02em; }
.seal__t { font-family: var(--font-mono); font-size: .72rem; letter-spacing: .16em; text-transform: uppercase; color: var(--slate); margin-top: .4rem; }
.seal__y { font-family: var(--font-mono); font-size: .8rem; color: var(--ink); margin-top: .8rem; }

/* ============================================== sustentabilidade (Luzia / carste) */
.sust { position: relative; overflow: hidden; }
.sust__bg { position: absolute; inset: 0; z-index: 0; opacity: .18; }
.sust__bg img { width: 100%; height: 100%; object-fit: cover; filter: grayscale(1); }
.sust .container { position: relative; z-index: 1; }
.sust__grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem,5vw,4rem); align-items: center; }
.luzia-card { background: var(--basalt-2); border: 1px solid rgba(239,233,221,.14); border-radius: var(--radius); padding: 2rem; }
.luzia-card .big { font-family: var(--font-mono); font-size: clamp(2rem,4vw,2.8rem); font-weight: 600; color: var(--ochre); letter-spacing: -.02em; }
.luzia-card .cap { all: unset; display: block; color: var(--slate-on-dark); font-size: .95rem; margin-top: .5rem; }
.pill-list { list-style: none; margin: 1.5rem 0 0; padding: 0; display: grid; gap: .8rem; }
.pill-list li { display: flex; gap: .8rem; align-items: flex-start; color: var(--paper-on-dark); font-size: .98rem; }
.pill-list li::before { content: "▸"; color: var(--oxide-bright); flex: none; margin-top: .1rem; }

/* ============================================================ notícias */
.news { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: clamp(1.2rem,3vw,2rem); margin-top: 3rem; }
.newscard {
  background: var(--limestone-2); border: 1px solid var(--stone); border-radius: var(--radius);
  overflow: hidden; display: flex; flex-direction: column; transition: transform .3s var(--ease), box-shadow .3s var(--ease);
}
.newscard:hover { transform: translateY(-4px); box-shadow: 0 18px 40px -24px rgba(22,19,14,.5); }
.newscard__img { aspect-ratio: 16/10; overflow: hidden; background: var(--stone); }
.newscard__img img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s var(--ease); }
.newscard:hover .newscard__img img { transform: scale(1.05); }
.newscard__body { padding: 1.4rem 1.5rem 1.6rem; display: flex; flex-direction: column; flex: 1; }
.newscard__tag { font-family: var(--font-mono); font-size: .64rem; letter-spacing: .16em; text-transform: uppercase; color: var(--oxide); margin-bottom: .6rem; }
.newscard h3 { font-size: 1.2rem; margin-bottom: .6rem; }
.newscard p { color: var(--slate); font-size: .92rem; margin: 0 0 1rem; }
.newscard__more { font-family: var(--font-mono); font-size: .74rem; letter-spacing: .08em; text-transform: uppercase; color: var(--oxide); margin-top: auto; }

/* ============================================================ contato */
.contact { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem,5vw,4rem); }
.contact__info dl { margin: 2rem 0 0; display: grid; gap: 1.4rem; }
.contact__info dt { font-family: var(--font-mono); font-size: .68rem; letter-spacing: .16em; text-transform: uppercase; color: var(--oxide); }
.contact__info dd { margin: .3rem 0 0; font-size: 1.05rem; }
.contact__info a:hover { color: var(--oxide); }
.mapframe { margin-top: 2rem; border: 1px solid var(--stone); border-radius: var(--radius); overflow: hidden; aspect-ratio: 16/10; }
.mapframe iframe { width: 100%; height: 100%; border: 0; filter: grayscale(.4); }

.form { display: grid; gap: 1rem; }
.field { display: grid; gap: .4rem; }
.field label { font-family: var(--font-mono); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; color: var(--slate); }
.field input, .field textarea {
  font-family: var(--font-body); font-size: 1rem; color: var(--ink);
  padding: .8rem .9rem; background: var(--limestone-2); border: 1px solid var(--stone); border-radius: var(--radius);
  transition: border-color .2s;
}
.field input:focus, .field textarea:focus { outline: none; border-color: var(--oxide); }
.form__row { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.form__note { font-size: .8rem; color: var(--slate); }

/* ============================================================ footer */
.site-footer { background: var(--basalt); color: var(--slate-on-dark); padding-block: clamp(3rem,6vw,5rem) 2rem; }
.footer__top { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 2.5rem; padding-bottom: 3rem; border-bottom: 1px solid rgba(239,233,221,.12); }
.footer__brand .brand__name { color: var(--paper-on-dark); }
.footer__brand p { max-width: 34ch; font-size: .92rem; margin-top: 1rem; }
.footer h4 { font-family: var(--font-mono); font-size: .7rem; letter-spacing: .16em; text-transform: uppercase; color: var(--ochre); margin: 0 0 1.1rem; }
.footer ul { list-style: none; margin: 0; padding: 0; display: grid; gap: .6rem; }
.footer a { font-size: .92rem; }
.footer a:hover { color: var(--paper-on-dark); }
.footer__partners { display: flex; gap: 1rem; align-items: center; margin-top: 1rem; flex-wrap: wrap; }
.footer__partners img { height: 34px; width: auto; opacity: .7; filter: grayscale(1) brightness(1.6); }
.footer__bottom { display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; padding-top: 1.8rem; font-family: var(--font-mono); font-size: .72rem; letter-spacing: .04em; color: var(--slate-on-dark); }

/* ===================================================== ASSISTENTE IA (chat) */
.chat-fab {
  position: fixed; right: clamp(1rem,3vw,2rem); bottom: clamp(1rem,3vw,2rem); z-index: 80;
  display: flex; align-items: center; gap: .6rem;
  background: var(--oxide); color: var(--limestone-2);
  border: 0; border-radius: 999px; padding: .85rem 1.3rem .85rem 1.1rem; cursor: pointer;
  font-family: var(--font-mono); font-size: .8rem; letter-spacing: .04em; text-transform: uppercase; font-weight: 500;
  box-shadow: 0 12px 30px -10px rgba(166,42,27,.7); transition: transform .2s var(--ease), background .2s;
}
.chat-fab:hover { background: var(--oxide-bright); transform: translateY(-2px); }
.chat-fab svg { width: 20px; height: 20px; }
.chat-fab.is-hidden { display: none; }

.chat-panel {
  position: fixed; right: clamp(1rem,3vw,2rem); bottom: clamp(1rem,3vw,2rem); z-index: 90;
  width: min(400px, calc(100vw - 2rem)); height: min(600px, calc(100vh - 2rem));
  background: var(--limestone-2); border: 1px solid var(--stone); border-radius: 10px;
  display: flex; flex-direction: column; overflow: hidden;
  box-shadow: 0 30px 70px -25px rgba(22,19,14,.6);
  transform: translateY(20px) scale(.98); opacity: 0; pointer-events: none;
  transition: opacity .3s var(--ease), transform .3s var(--ease);
}
.chat-panel.is-open { opacity: 1; transform: none; pointer-events: auto; }
.chat-head { background: var(--basalt); color: var(--paper-on-dark); padding: 1rem 1.2rem; display: flex; align-items: center; gap: .8rem; }
.chat-head__av { width: 38px; height: 38px; border-radius: 50%; background: var(--oxide); display: grid; place-content: center; font-family: var(--font-display); font-weight: 800; color: var(--limestone-2); flex: none; }
.chat-head__t { flex: 1; line-height: 1.2; }
.chat-head__t strong { font-family: var(--font-display); font-size: .98rem; }
.chat-head__t span { display: block; font-family: var(--font-mono); font-size: .64rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ochre); margin-top: 2px; }
.chat-head__t span::before { content: "● "; color: #5db56a; }
.chat-close { background: none; border: 0; color: var(--slate-on-dark); cursor: pointer; padding: 6px; border-radius: 4px; }
.chat-close:hover { color: var(--paper-on-dark); }

.chat-log { flex: 1; overflow-y: auto; padding: 1.2rem; display: flex; flex-direction: column; gap: .9rem; scroll-behavior: smooth; }
.msg { max-width: 85%; padding: .7rem .95rem; border-radius: 12px; font-size: .92rem; line-height: 1.5; }
.msg--bot { background: #fff; border: 1px solid var(--stone); border-bottom-left-radius: 3px; align-self: flex-start; }
.msg--user { background: var(--oxide); color: var(--limestone-2); border-bottom-right-radius: 3px; align-self: flex-end; }
.msg--bot strong { color: var(--oxide); }
.msg p { margin: 0 0 .5rem; } .msg p:last-child { margin: 0; }
.chat-typing { align-self: flex-start; display: inline-flex; gap: 4px; padding: .8rem 1rem; background: #fff; border: 1px solid var(--stone); border-radius: 12px; border-bottom-left-radius: 3px; }
.chat-typing span { width: 6px; height: 6px; background: var(--slate); border-radius: 50%; animation: blink 1.2s infinite; }
.chat-typing span:nth-child(2) { animation-delay: .2s; } .chat-typing span:nth-child(3) { animation-delay: .4s; }
@keyframes blink { 0%,60%,100% { opacity: .25; } 30% { opacity: 1; } }

.chat-suggest { display: flex; gap: .5rem; flex-wrap: wrap; padding: 0 1.2rem .8rem; }
.chat-suggest button {
  font-family: var(--font-mono); font-size: .68rem; letter-spacing: .02em;
  background: transparent; border: 1px solid var(--stone); color: var(--slate);
  padding: .4rem .7rem; border-radius: 999px; cursor: pointer; transition: .2s;
}
.chat-suggest button:hover { border-color: var(--oxide); color: var(--oxide); }

.chat-form { display: flex; gap: .5rem; padding: .8rem 1rem 1rem; border-top: 1px solid var(--stone); background: var(--limestone-2); }
.chat-form input { flex: 1; font-family: var(--font-body); font-size: .92rem; padding: .7rem .9rem; border: 1px solid var(--stone); border-radius: 999px; background: #fff; }
.chat-form input:focus { outline: none; border-color: var(--oxide); }
.chat-form button { flex: none; width: 42px; height: 42px; border-radius: 50%; border: 0; background: var(--oxide); color: var(--limestone-2); cursor: pointer; display: grid; place-content: center; transition: background .2s; }
.chat-form button:hover { background: var(--oxide-bright); }
.chat-form button:disabled { opacity: .5; cursor: not-allowed; }
.chat-disclaimer { font-size: .64rem; color: var(--slate); text-align: center; padding: 0 1rem .7rem; font-family: var(--font-mono); }

/* ===================================================== responsivo */
@media (max-width: 900px) {
  .split, .quality, .sust__grid, .contact, .assays, .duo, .footer__top { grid-template-columns: 1fr; }
  .datastrip__grid { grid-template-columns: 1fr 1fr; }
  .datastrip__cell:nth-child(-n+2) { border-bottom: 1px solid rgba(239,233,221,.1); }
  .datastrip__cell:nth-child(odd) { border-left: 0; }
  .form__row { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .nav__links {
    position: fixed; inset: 74px 0 auto 0; flex-direction: column; align-items: stretch;
    background: var(--limestone-2); border-bottom: 1px solid var(--stone); padding: 1rem var(--gutter) 1.5rem;
    gap: 0; transform: translateY(-120%); transition: transform .35s var(--ease); box-shadow: 0 20px 40px -20px rgba(0,0,0,.3);
  }
  .nav__links.is-open { transform: none; }
  .nav__links li { border-bottom: 1px solid var(--stone); }
  .nav__links a { display: block; padding: .9rem 0; font-size: 1rem; }
  .nav__toggle { display: block; }
  .nav__cta .btn { display: none; }
  .datastrip__grid { grid-template-columns: 1fr; }
  .datastrip__cell { border-left: 0 !important; border-bottom: 1px solid rgba(239,233,221,.1); }
}