/* ============================================================
   Argument Theory — rAIson
   Shared stylesheet
   ============================================================ */

:root {
  --ink:        #14201E;
  --ink-soft:   #2C3A37;
  --hero-bg:    #21302C;
  --teal:       #0F7765;
  --teal-bright:#16A085;
  --teal-deep:  #0A5648;
  --paper:      #FBFAF7;
  --paper-2:    #EFEAE2;
  --panel:      #F4F1EA;
  --rule:       #DDD6C9;
  --muted:      #6A6F69;
  --neuro:      #1D6FB8;   /* the LLM / "reads" half */
  --brand-blue: #1F528A;   /* logo deep blue */
  --brand-teal: #00A19A;   /* logo bright teal */
  --hero-grad:  linear-gradient(120deg, #18243A 0%, #173A3F 55%, #0E3A38 100%);

  --serif:  Charter, "Bitstream Charter", Cambria, "Source Serif Pro", Georgia, serif;
  --sans:   -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --mono:   ui-monospace, SFMono-Regular, "JetBrains Mono", Menlo, Consolas, monospace;

  --wrap: 72rem;
}

*,*::before,*::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--teal); text-decoration: none; }
a:hover { color: var(--teal-deep); }
h1,h2,h3 { font-family: var(--serif); font-weight: 600; letter-spacing: -0.015em; line-height: 1.12; }

/* rAIson wordmark */
.raison {
  font-family: var(--serif);
  font-weight: 700;
  color: var(--teal);
  letter-spacing: -0.01em;
}
.raison .ai { font-size: 0.72em; vertical-align: baseline; color: var(--teal-bright); }
.on-dark .raison, .raison.on-dark { color: #fff; }
.on-dark .raison .ai { color: var(--teal-bright); }

/* ---- header ---- */
.site-head {
  position: sticky; top: 0; z-index: 50;
  background: rgba(251,250,247,0.92);
  backdrop-filter: saturate(1.2) blur(8px);
  border-bottom: 1px solid var(--rule);
}
.site-head__in {
  max-width: var(--wrap); margin: 0 auto;
  padding: 1.05rem 1.5rem;
  display: flex; align-items: center; justify-content: space-between; gap: 1.5rem;
}
.brand { display: flex; align-items: center; gap: 0.6rem; border: none; }
.brand__logo-img { height: 52px; width: auto; display: block; flex: none; }

.nav { display: flex; align-items: center; gap: 1.4rem; }
.nav a {
  font-size: 0.92rem; color: var(--ink-soft); font-weight: 500;
  padding: 0.3rem 0; position: relative;
}
.nav a:hover { color: var(--teal); }
.nav a.current { color: var(--teal); }
.nav a.current::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -2px; height: 2px;
  background: var(--teal);
}
.nav__cta {
  background: var(--ink); color: #fff !important;
  padding: 0.5rem 0.95rem; border-radius: 8px; font-weight: 600;
}
.nav__cta:hover { background: var(--teal-deep); }

.nav-toggle { display: none; background: none; border: 1px solid var(--rule); border-radius: 8px;
  width: 42px; height: 38px; cursor: pointer; align-items: center; justify-content: center; }
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  content: ""; display: block; width: 18px; height: 2px; background: var(--ink); position: relative;
}
.nav-toggle span::before { position: absolute; top: -6px; }
.nav-toggle span::after { position: absolute; top: 6px; }

@media (max-width: 820px) {
  .nav-toggle { display: inline-flex; }
  .nav {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--paper); border-bottom: 1px solid var(--rule);
    padding: 0.5rem 1.5rem 1rem;
    display: none;
  }
  .nav.open { display: flex; }
  .nav a { padding: 0.7rem 0; border-bottom: 1px solid var(--rule); }
  .nav a.current::after { display: none; }
  .nav__cta { margin-top: 0.7rem; text-align: center; border-bottom: none; }
}

/* ---- layout primitives ---- */
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 1.5rem; }
section { padding: 5rem 0; }
.section-tight { padding: 3.5rem 0; }
.eyebrow {
  font-family: var(--sans); font-size: 0.72rem; font-weight: 700;
  letter-spacing: 0.18em; text-transform: uppercase; color: var(--teal);
  margin: 0 0 0.9rem;
}
.eyebrow.muted { color: var(--muted); }
.lede { font-size: 1.22rem; line-height: 1.5; color: var(--ink-soft); max-width: 40ch; }
.kicker { color: var(--muted); font-size: 1.02rem; max-width: 78ch; }

/* ---- hero ---- */
.hero { background: var(--hero-grad); color: #F4F1EA; padding: 6rem 0 5.5rem; position: relative; overflow: hidden; }
.hero h1 { color: #fff; font-size: clamp(2.3rem, 5.2vw, 3.9rem); margin: 0 0 1.3rem; max-width: 26ch; }
.hero p.lede { color: #C9D2CF; max-width: 46ch; }
.hero .raison { color: #fff; }
.hero .raison .ai { color: var(--teal-bright); }
.hero__cta { margin-top: 2.2rem; display: flex; gap: 0.8rem; flex-wrap: wrap; }
.btn {
  display: inline-block; font-weight: 600; font-size: 0.98rem;
  padding: 0.75rem 1.3rem; border-radius: 9px; border: 1px solid transparent; cursor: pointer;
}
.btn--primary { background: var(--teal); color: #fff; }
.btn--primary:hover { background: var(--teal-bright); color: #fff; }
.btn--ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,0.32); }
.btn--ghost:hover { border-color: #fff; color: #fff; }
.btn--dark { background: var(--ink); color: #fff; }
.btn--dark:hover { background: var(--teal-deep); color: #fff; }

/* neuro→symbolic motif */
.duo {
  display: grid; grid-template-columns: 1fr auto 1fr; gap: 0; align-items: stretch;
  margin-top: 3rem; border: 1px solid rgba(255,255,255,0.16); border-radius: 14px; overflow: hidden;
}
.duo__half { padding: 1.6rem 1.5rem; }
.duo__half h3 { font-size: 1.18rem; margin: 0.5rem 0 0.7rem; color: #fff; }
.duo__half ul { margin: 0; padding-left: 1.1rem; color: #C9D2CF; font-size: 0.95rem; line-height: 1.5; }
.duo__half li { margin-bottom: 0.35rem; }
.duo__tag { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.12em; text-transform: uppercase; }
.duo__half--neuro { background: rgba(29,111,184,0.14); }
.duo__half--neuro .duo__tag { color: #6FB1E8; }
.duo__half--sym { background: rgba(22,160,133,0.14); }
.duo__half--sym .duo__tag { color: var(--teal-bright); }
.duo__join {
  display: grid; place-items: center; padding: 0 0.9rem;
  background: rgba(255,255,255,0.04);
}
.duo__arrow {
  width: 56px; height: 56px; border-radius: 50%;
  display: grid; place-items: center;
  background: var(--teal); color: #fff;
  box-shadow: 0 6px 18px rgba(0,0,0,0.28);
  border: 3px solid rgba(255,255,255,0.16);
}
.duo__arrow svg { width: 28px; height: 28px; }
@media (max-width: 720px) {
  .duo { grid-template-columns: 1fr; }
  .duo__join { padding: 0.6rem; }
  .duo__join .duo__arrow svg { transform: rotate(90deg); }
}

/* ---- generic cards ---- */
.grid { display: grid; gap: 1.2rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 620px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }

.card {
  background: #fff; border: 1px solid var(--rule); border-radius: 13px;
  padding: 1.5rem 1.4rem;
}
.card h3 { font-size: 1.18rem; margin: 0 0 0.5rem; }
.card p { margin: 0; color: var(--ink-soft); font-size: 0.96rem; }
.card__ico {
  width: 40px; height: 40px; border-radius: 10px; background: var(--panel);
  display: grid; place-items: center; margin-bottom: 1rem; color: var(--teal);
}
.card__ico svg { width: 21px; height: 21px; }

.panel { background: var(--panel); }
.panel-deep { background: var(--ink); color: #E6ECEA; }
.panel-deep h2 { color: #fff; }
.panel-deep .eyebrow { color: var(--teal-bright); }

/* feature row */
.featrow { display: grid; grid-template-columns: 1.1fr 1fr; gap: 3rem; align-items: center; }
.featrow.rev { grid-template-columns: 1fr 1.1fr; }
@media (max-width: 820px) { .featrow, .featrow.rev { grid-template-columns: 1fr; gap: 1.6rem; } }
.featrow h2 { font-size: clamp(1.7rem, 3.4vw, 2.3rem); margin: 0 0 1rem; }
.featrow p { color: var(--ink-soft); margin: 0 0 1rem; }

/* numbered workflow */
.flow { display: grid; gap: 1.1rem; }
.flow__item {
  background: #fff; border: 1px solid var(--rule); border-radius: 13px;
  padding: 1.4rem 1.5rem 1.5rem; display: grid; grid-template-columns: 3rem 1fr; gap: 1rem; align-items: start;
}
.flow__num {
  font-family: var(--serif); font-weight: 700; font-size: 1.6rem; color: var(--teal);
  width: 3rem; height: 3rem; border-radius: 50%; background: var(--panel);
  display: grid; place-items: center;
}
.flow__item h3 { margin: 0.2rem 0 0.2rem; font-size: 1.22rem; }
.flow__who { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
.flow__steps { list-style: none; margin: 0.8rem 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 0.4rem; align-items: center; }
.flow__steps li {
  font-size: 0.85rem; color: var(--ink-soft); background: var(--paper-2);
  border: 1px solid var(--rule); border-radius: 999px; padding: 0.28rem 0.7rem;
}
.flow__steps li.arrow { background: none; border: none; color: var(--teal); padding: 0 0.1rem; }

/* stat band */
.stats { display: grid; grid-template-columns: repeat(3,1fr); gap: 2rem; }
@media (max-width: 700px){ .stats { grid-template-columns: 1fr; gap: 1.4rem; } }
.stat__n { font-family: var(--serif); font-weight: 700; font-size: clamp(2.2rem,5vw,3rem); color: var(--teal-bright); line-height: 1; }
.stat__l { margin-top: 0.5rem; color: #C9D2CF; font-size: 0.95rem; }

/* domain pills */
.domains { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 1.5rem; }
.domains li {
  list-style: none; font-size: 0.9rem; color: var(--ink-soft);
  background: #fff; border: 1px solid var(--rule); border-radius: 999px; padding: 0.4rem 0.9rem;
}
.domains li::before { content: "·"; color: var(--teal); font-weight: 700; margin-right: 0.45rem; }

/* compliance list */
.reg { display: grid; gap: 1rem; }
.reg__item { background: #fff; border: 1px solid var(--rule); border-radius: 13px; padding: 1.3rem 1.5rem; }
.reg__item h3 { margin: 0 0 0.4rem; font-size: 1.1rem; }
.reg__tag { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; color: var(--teal); text-transform: uppercase; }
.reg__item p { margin: 0.3rem 0 0; color: var(--ink-soft); font-size: 0.95rem; }

/* CTA band */
.cta-band { background: var(--teal); color: #fff; text-align: center; }
.cta-band h2 { color: #fff; font-size: clamp(1.8rem,4vw,2.6rem); margin: 0 0 0.8rem; }
.cta-band p { color: #Dff0EB; max-width: 48ch; margin: 0 auto 1.6rem; }
.cta-band .raison { color: #fff; }
.cta-band .raison .ai { color: #BfeFe5; }

/* footer */
.foot { background: var(--ink); color: #AEB7B4; padding: 3rem 0 2.4rem; }
.foot__grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 2rem; }
@media (max-width: 760px){ .foot__grid { grid-template-columns: 1fr; gap: 1.6rem; } }
.foot h4 { color: #fff; font-family: var(--sans); font-size: 0.78rem; letter-spacing: 0.14em; text-transform: uppercase; margin: 0 0 0.9rem; }
.foot a { color: #AEB7B4; display: block; padding: 0.22rem 0; font-size: 0.95rem; }
.foot a:hover { color: #fff; }
.foot__brand .raison { color: #fff; font-size: 1.3rem; }
.foot__logo { height: 58px; width: auto; display: block; }
.foot__by { color: #C9D2CF; font-size: 0.95rem; margin: 0.7rem 0 0; }
.foot__by strong { color: #fff; font-weight: 600; }
.foot__brand p { font-size: 0.92rem; max-width: 34ch; margin: 0.4rem 0 0; }
.foot__brand .foot__by { margin-top: 0.7rem; }
.foot__base { border-top: 1px solid rgba(255,255,255,0.12); margin-top: 2.2rem; padding-top: 1.4rem;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.6rem; font-size: 0.85rem; color: #8A938F; }

/* page hero (interior) */
.phead { background: var(--hero-grad); border-bottom: 1px solid rgba(255,255,255,0.1); padding: 4rem 0 3.2rem; color: #E6ECEA; }
.phead h1 { font-size: clamp(2rem,4.6vw,3rem); margin: 0 0 1rem; max-width: 28ch; color: #fff; }
.phead p { color: #C9D2CF; font-size: 1.12rem; max-width: 70ch; margin: 0; }
.phead .eyebrow { color: var(--teal-bright); }
.phead .raison { color: #fff; }
.phead .raison .ai { color: var(--teal-bright); }

/* prose helpers */
.measure { max-width: 62ch; }
.note { font-size: 0.9rem; color: var(--muted); }
.ref { font-family: var(--mono); font-size: 0.82rem; color: var(--muted); }

/* ---- use-case videos ---- */
.vgrid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.6rem; }
@media (max-width: 760px) { .vgrid { grid-template-columns: 1fr; } }
.vcard {
  background: #fff; border: 1px solid var(--rule); border-radius: 14px; overflow: hidden;
  display: flex; flex-direction: column;
}
.vcard__frame {
  position: relative; width: 100%; aspect-ratio: 16 / 9; background: var(--ink);
}
.vcard__frame iframe, .vcard__frame video {
  position: absolute; inset: 0; width: 100%; height: 100%; border: 0; display: block;
}
/* placeholder shown when no media wired yet */
.vcard__ph {
  position: absolute; inset: 0; display: grid; place-items: center; text-align: center;
  background:
    radial-gradient(120% 120% at 50% 0%, rgba(22,160,133,0.18), transparent 60%),
    var(--ink);
  color: #C9D2CF; padding: 1.5rem;
}
.vcard__play {
  width: 54px; height: 54px; border-radius: 50%; background: var(--teal);
  display: grid; place-items: center; margin: 0 auto 0.8rem;
}
.vcard__play svg { width: 22px; height: 22px; fill: #fff; margin-left: 3px; }
.vcard__ph small { display: block; font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; color: #8FA39E; margin-top: 0.3rem; }
.vcard__body { padding: 1.2rem 1.4rem 1.4rem; }
.vcard__domain { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--teal); }
.vcard__body h3 { font-size: 1.18rem; margin: 0.4rem 0 0.45rem; }
.vcard__body p { margin: 0; color: var(--ink-soft); font-size: 0.95rem; }

.channel-band {
  display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; flex-wrap: wrap;
  background: var(--panel); border: 1px solid var(--rule); border-radius: 14px;
  padding: 1.6rem 1.8rem;
}
.channel-band h3 { margin: 0 0 0.3rem; font-size: 1.25rem; }
.channel-band p { margin: 0; color: var(--ink-soft); font-size: 0.96rem; }

/* ---- contact form ---- */
.cform { display: grid; gap: 1.1rem; }
.cform__row { display: grid; grid-template-columns: 1fr 1fr; gap: 1.1rem; }
@media (max-width: 600px) { .cform__row { grid-template-columns: 1fr; } }
.cform label { display: grid; gap: 0.4rem; font-size: 0.9rem; font-weight: 600; color: var(--ink); }
.cform label .note { font-weight: 400; }
.cform input, .cform select, .cform textarea {
  font: inherit; font-weight: 400; color: var(--ink);
  background: #fff; border: 1px solid var(--rule); border-radius: 9px;
  padding: 0.7rem 0.85rem; width: 100%;
}
.cform textarea { resize: vertical; }
.cform input:focus, .cform select:focus, .cform textarea:focus {
  outline: none; border-color: var(--teal); box-shadow: 0 0 0 3px rgba(15,119,101,0.14);
}
.cform__actions { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; }

/* focus visibility */
a:focus-visible, .btn:focus-visible, button:focus-visible {
  outline: 2px solid var(--teal-bright); outline-offset: 3px; border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}