/* Celsus — minimal marketing site
   Calm, typographic, text-led. Fire gradient used sparingly as accent. */

:root {
  --paper: #FBFAF8;
  --paper-2: #F4F2ED;
  --ink: #16131A;
  --ink-soft: #4A4550;
  --ink-faint: #8C8694;
  --line: #E7E3DC;

  /* Brand fire gradient */
  --fire: linear-gradient(180deg, #FF8A1E 0%, #FB4A3F 38%, #EF2C7E 78%, #C13A9E 100%);
  --fire-h: linear-gradient(90deg, #FF8A1E 0%, #FB4A3F 45%, #EF2C7E 100%);
  --ember: #EF2C7E;

  --serif: ui-serif, Georgia, "Times New Roman", serif;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  --maxw: 920px;
  --gutter: clamp(20px, 5vw, 48px);
}

* { 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;
  text-rendering: optimizeLegibility;
}

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--ink);
  color: var(--paper);
  padding: 10px 16px;
  border-radius: 8px;
  z-index: 10;
}
.skip:focus { left: 16px; top: 16px; }

/* ---- Layout primitives ---- */
main { display: block; }

section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(64px, 11vw, 132px) var(--gutter);
  border-top: 1px solid var(--line);
}
section:first-of-type { border-top: 0; }

.section-title {
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 2.4rem;
}

/* ---- Header ---- */
.site-header {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 22px var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
}
.brand__mark { display: block; border-radius: 7px; }
.brand__word {
  font-family: var(--serif);
  font-size: 1.25rem;
  letter-spacing: 0.01em;
  font-weight: 600;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font: inherit;
  font-weight: 550;
  text-decoration: none;
  border-radius: 999px;
  padding: 12px 22px;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease, color .2s ease;
  white-space: nowrap;
}
.btn--primary {
  color: #fff;
  background: var(--ink);
  position: relative;
}
.btn--primary:hover { transform: translateY(-1px); box-shadow: 0 8px 24px rgba(22,19,26,.18); }
.btn--lg { padding: 16px 32px; font-size: 1.05rem; }
.btn--ghost {
  color: var(--ink);
  border: 1px solid var(--line);
  background: transparent;
}
.btn--ghost:hover { border-color: var(--ink); }
.btn--text {
  color: var(--ink-soft);
  padding-left: 8px;
  padding-right: 8px;
}
.btn--text:hover { color: var(--ember); }

/* ---- Hero ---- */
.hero { padding-top: clamp(48px, 9vw, 96px); }
.eyebrow {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 1.6rem;
}
.eyebrow::before {
  content: "";
  display: inline-block;
  width: 26px; height: 3px;
  border-radius: 2px;
  background: var(--fire-h);
  vertical-align: middle;
  margin-right: 12px;
  transform: translateY(-2px);
}
.hero__title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(2.7rem, 8vw, 5rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  margin: 0 0 1.6rem;
  max-width: 14ch;
}
.hero__sub {
  font-size: clamp(1.1rem, 2.4vw, 1.4rem);
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 56ch;
  margin: 0 0 2.6rem;
}
.hero__actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

/* ---- Product loop ---- */
.flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: stretch;
  gap: 0;
  flex-wrap: wrap;
}
.flow__node {
  flex: 1 1 140px;
  min-width: 140px;
  position: relative;
  padding: 22px 20px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 0 18px 18px 0;
}
/* connector arrows between nodes */
.flow__node:not(:last-child)::after {
  content: "→";
  position: absolute;
  right: -18px;
  top: 50%;
  width: 18px;
  transform: translateY(-50%);
  text-align: center;
  color: var(--ink-faint);
  font-size: 1rem;
}
.flow__num {
  font-family: var(--serif);
  font-size: 0.85rem;
  color: var(--ember);
  letter-spacing: 0.04em;
}
.flow__label { font-weight: 600; letter-spacing: -0.01em; }
.flow__node--human {
  border-color: transparent;
  background:
    linear-gradient(#fff, #fff) padding-box,
    var(--fire) border-box;
  border: 1.5px solid transparent;
}
.flow__node--human .flow__num { color: var(--ember); }

.loop__note {
  margin: 2rem 0 0;
  color: var(--ink-soft);
  font-size: 1.05rem;
  max-width: 52ch;
}

/* ---- Trust ---- */
.trust__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(24px, 4vw, 48px);
}
.trust__item h3 {
  font-family: var(--serif);
  font-size: 1.3rem;
  font-weight: 600;
  margin: 0 0 0.6rem;
  letter-spacing: -0.01em;
}
.trust__item h3::before {
  content: "";
  display: block;
  width: 30px; height: 3px;
  border-radius: 2px;
  background: var(--fire-h);
  margin-bottom: 14px;
}
.trust__item p { margin: 0; color: var(--ink-soft); }

/* ---- Boundary ---- */
.boundary__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.boundary__list li {
  padding: 18px 0;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 1.05rem;
}
.boundary__list li:first-child { border-top: 0; }
.boundary__key {
  display: inline-block;
  min-width: 140px;
  color: var(--ink);
  font-weight: 600;
  margin-right: 12px;
}

/* ---- CTA ---- */
.cta { text-align: center; }
.cta__title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(1.8rem, 5vw, 3rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
}
.cta__sub {
  color: var(--ink-soft);
  margin: 0 auto 2.2rem;
  max-width: 42ch;
}

/* ---- Brand-treated proof band (single duotone image) ---- */
.proof-band {
  max-width: none;
  padding: 0;
  position: relative;
  isolation: isolate;
  overflow: hidden;
}
/* duotone: gradient hue/sat + photo luminance via 'color' blend */
.proof-band::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(135deg, #FF8A1E 0%, #EF2C7E 55%, #C13A9E 100%),
    url("assets/proof.jpg");
  background-size: cover, cover;
  background-position: center, center 35%;
  background-repeat: no-repeat, no-repeat;
  background-blend-mode: color;
}
/* dark scrim for legibility + calm */
.proof-band::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(180deg, rgba(10,9,16,.62), rgba(10,9,16,.82));
}
.proof-band__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(80px, 13vw, 156px) var(--gutter);
}
.proof-band__quote {
  margin: 0;
  font-family: var(--serif);
  font-weight: 600;
  color: #fff;
  font-size: clamp(1.7rem, 4.6vw, 2.9rem);
  line-height: 1.16;
  letter-spacing: -0.02em;
  max-width: 22ch;
  text-wrap: balance;
}

/* ---- Footer ---- */

.site-footer {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 40px var(--gutter) 64px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.brand--footer .brand__word { font-size: 1.05rem; }
.site-footer__legal {
  margin: 0;
  color: var(--ink-faint);
  font-size: 0.9rem;
}
.site-footer__mail {
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
}
.site-footer__mail:hover { color: var(--ember); border-color: var(--ember); }
.site-footer__sep { margin: 0 8px; opacity: .6; }


/* ---- Responsive ---- */
@media (max-width: 720px) {
  .header__cta { display: none; }
  .trust__grid { grid-template-columns: 1fr; }
  .flow__node { flex-basis: 100%; margin-right: 0; }
  .flow__node:not(:last-child)::after {
    content: "↓";
    right: auto;
    left: 50%;
    top: auto;
    bottom: -18px;
    transform: translateX(-50%);
  }
  .boundary__key { display: block; margin-bottom: 4px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
}