/* Beyond the Chemistry: website styles (tokens from Brand Template v1.0, section 9) */
:root {
  --btc-charcoal: #1D1D1B;
  --btc-soft-charcoal: #343432;
  --btc-graphite: #52514E;
  --btc-stone: #8D8A84;
  --btc-greige: #CAC5BC;
  --btc-ivory: #F4F0E8;
  --btc-pale-ivory: #FAF8F3;

  --font-display: "Bebas Neue", "Antonio", "Arial Narrow", Impact, sans-serif;
  --font-body: "Inter", -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;

  --text-hero: clamp(3.5rem, 9vw, 7.5rem);
  --text-h2: clamp(2.25rem, 5vw, 4rem);
  --text-h3: 1.75rem;
  --text-label: 0.8125rem;
  --text-body: 1.125rem;
  --text-small: 0.875rem;

  --max-width: 1120px;
  --reading-width: 680px;
  --space-section: clamp(4rem, 10vw, 8rem);
  --gutter: clamp(1.25rem, 4vw, 2.5rem);
  --rule: 1px solid var(--btc-greige);
  --radius: 0;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 80px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; } }
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.6;
  color: var(--btc-charcoal);
  background: var(--btc-pale-ivory);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-underline-offset: 3px; text-decoration-thickness: 1px; }
p { margin: 0 0 1em; max-width: 60ch; }
h1, h2, h3 { font-family: var(--font-display); font-weight: 400; text-transform: uppercase; line-height: 0.92; letter-spacing: 0.005em; margin: 0; text-wrap: balance; }
h1 { font-size: var(--text-hero); }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); line-height: 1; }
:focus-visible { outline: 2px solid currentColor; outline-offset: 3px; }

.wrap { width: 100%; max-width: var(--max-width); margin: 0 auto; padding: 0 var(--gutter); }
.label {
  font-family: var(--font-body); font-weight: 600; font-size: var(--text-label);
  text-transform: uppercase; letter-spacing: 0.12em; margin: 0 0 1.25rem; display: block;
}
.rule { width: 56px; height: 3px; background: var(--btc-stone); border: 0; margin: 1.5rem 0; }
.slash { color: var(--btc-stone); }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* Sections */
.dark { background: var(--btc-charcoal); color: var(--btc-ivory); }
.dark .label { color: var(--btc-stone); }
.dark p { color: var(--btc-greige); }
.ivory { background: var(--btc-ivory); }
.pale { background: var(--btc-pale-ivory); }
.ivory p, .pale p { color: var(--btc-graphite); }
section { padding: var(--space-section) 0; position: relative; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font-family: var(--font-body); font-weight: 600; font-size: .9375rem;
  text-transform: uppercase; letter-spacing: 0.08em; text-decoration: none;
  padding: 16px 28px; border: 1px solid transparent; border-radius: var(--radius);
  cursor: pointer; transition: background-color .18s ease, color .18s ease, border-color .18s ease;
  background: var(--btc-charcoal); color: var(--btc-ivory); white-space: nowrap;
}
.btn:hover { background: var(--btc-soft-charcoal); }
.dark .btn, .btn-light { background: var(--btc-ivory); color: var(--btc-charcoal); }
.dark .btn:hover, .btn-light:hover { background: var(--btc-greige); }
.btn[disabled] { opacity: .6; cursor: progress; }
.btn-outline { background: transparent; border-color: currentColor; color: inherit; }
.dark .btn-outline { background: transparent; color: var(--btc-ivory); }
.dark .btn-outline:hover, .btn-outline:hover { background: var(--btc-soft-charcoal); color: var(--btc-ivory); }
.textlink { font-weight: 500; }

/* Nav */
.nav { position: sticky; top: 0; z-index: 50; background: var(--btc-charcoal); color: var(--btc-ivory); border-bottom: 1px solid var(--btc-soft-charcoal); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 72px; gap: 1.5rem; }
.nav-logo img { height: 48px; width: auto; }
.nav-links { display: flex; align-items: center; gap: 2rem; list-style: none; margin: 0; padding: 0; }
.nav-links a:not(.btn) { text-decoration: none; font-weight: 500; font-size: .9375rem; color: var(--btc-greige); }
.nav-links a:not(.btn):hover { color: var(--btc-ivory); }
.nav .btn { padding: 11px 18px; font-size: .8125rem; }
@media (max-width: 760px) {
  .nav-links li:not(:last-child) { display: none; }
  .nav-logo img { height: 36px; }
}

/* Hero */
.hero { padding: 0; overflow: hidden; min-height: min(86vh, 760px); display: flex; align-items: center; }
.hero-media { position: absolute; inset: 0; }
.hero-media img { width: 100%; height: 100%; object-fit: cover; object-position: 70% 50%; }
.hero-media::after { content: ""; position: absolute; inset: 0; background: rgba(29,29,27,.66); }
.hero .wrap { position: relative; padding-top: clamp(5rem, 12vw, 9rem); padding-bottom: clamp(5rem, 12vw, 9rem); }
.hero h1 { max-width: 11ch; }
.hero .label { color: var(--btc-greige); }
.hero-lede { font-size: 1.1875rem; max-width: 34rem; margin: 1.75rem 0 2.25rem; color: var(--btc-greige); }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1.5rem; }
.hero-actions .textlink { color: var(--btc-ivory); }
@media (max-width: 760px) {
  .hero-media::after { background: rgba(29,29,27,.72); }
  .hero-media img { object-position: 82% 50%; }
}

/* Lead magnet */
.lead-grid { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: clamp(2.5rem, 6vw, 6rem); align-items: center; }
@media (max-width: 860px) { .lead-grid { grid-template-columns: 1fr; } }
.checklist { list-style: none; padding: 0; margin: 1.75rem 0 2rem; }
.checklist li { position: relative; padding: .9rem 0 .9rem 2.25rem; border-top: var(--rule); color: var(--btc-charcoal); }
.checklist li:last-child { border-bottom: var(--rule); }
.checklist li::before { content: "/"; position: absolute; left: 0; top: .55rem; font-family: var(--font-display); font-size: 1.6rem; color: var(--btc-graphite); }

/* Cover mockup (CSS-built so it always matches the brand) */
.cover {
  aspect-ratio: 1600 / 2560; background: var(--btc-charcoal); color: var(--btc-ivory);
  padding: 9% 9% 8%; display: flex; flex-direction: column; position: relative; overflow: hidden;
  container-type: inline-size;
}
.cover-logo { width: 46%; }
.cover-title { font-family: var(--font-display); text-transform: uppercase; font-size: 17cqi; line-height: .9; margin-top: auto; }
.cover-rule { width: 22%; height: 2px; background: var(--btc-stone); margin: 7cqi 0 5cqi; }
.cover-label { font-weight: 600; font-size: 4.2cqi; letter-spacing: .14em; text-transform: uppercase; color: var(--btc-greige); }
.cover::after { content: "/"; position: absolute; right: -14%; top: 10%; font-family: var(--font-display); font-size: 120cqi; line-height: 1; color: var(--btc-soft-charcoal); z-index: 0; pointer-events: none; }
.cover > * { position: relative; z-index: 1; }
.lead-cover { max-width: 360px; width: 100%; justify-self: center; box-shadow: none; outline: 1px solid var(--btc-greige); outline-offset: 14px; }

/* Forms */
.signup { display: grid; grid-template-columns: 1fr 1.4fr auto; gap: .75rem; max-width: 640px; }
.signup.compact { grid-template-columns: 1.6fr auto; }
@media (max-width: 640px) { .signup, .signup.compact { grid-template-columns: 1fr; } }
.field { display: flex; flex-direction: column; }
.input {
  font: inherit; font-size: 1rem; padding: 15px 16px; border: 1px solid var(--btc-graphite);
  background: var(--btc-pale-ivory); color: var(--btc-charcoal); border-radius: var(--radius); width: 100%;
}
.input::placeholder { color: var(--btc-graphite); }
.input:focus { outline: 2px solid var(--btc-charcoal); outline-offset: 0; }
.dark .input { background: var(--btc-soft-charcoal); border-color: var(--btc-graphite); color: var(--btc-ivory); }
.dark .input::placeholder { color: var(--btc-greige); }
.dark .input:focus { outline-color: var(--btc-ivory); }
.form-note { font-size: var(--text-small); margin-top: 1rem; }
.form-msg { font-size: .9375rem; font-weight: 500; margin-top: 1rem; min-height: 1.5em; }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }

/* Split: CHEMISTRY / COMPATIBILITY */
.split { display: grid; grid-template-columns: 1fr 1fr; padding: 0; position: relative; }
.split > div { padding: clamp(4rem, 9vw, 7rem) clamp(1.5rem, 6vw, 5rem); }
.split .s-dark { background: var(--btc-charcoal); color: var(--btc-ivory); }
.split .s-light { background: var(--btc-ivory); }
.split h2 { font-size: clamp(2.5rem, 6vw, 5rem); }
.split p { margin-top: 1.25rem; }
.split .s-dark p { color: var(--btc-greige); }
.split .s-light p { color: var(--btc-graphite); }
.split-slash { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); font-family: var(--font-display); font-size: clamp(8rem, 18vw, 15rem); line-height: 1; color: var(--btc-stone); pointer-events: none; }
.split .s-dark .split-inner { margin-left: auto; max-width: 420px; padding-right: 3rem; }
.split .s-light .split-inner { max-width: 420px; padding-left: 3rem; }
@media (max-width: 760px) {
  .split { grid-template-columns: 1fr; }
  .split-slash { display: none; }
  .split .s-dark .split-inner, .split .s-light .split-inner { padding: 0; margin: 0; }
}

/* Pillars */
.section-head { display: flex; justify-content: space-between; align-items: end; gap: 2rem; margin-bottom: clamp(2.5rem, 5vw, 4rem); flex-wrap: wrap; }
.section-head p { margin: 0; max-width: 38ch; }
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); border-top: var(--rule); }
.pillar { padding: 2rem 2rem 2.25rem 0; border-bottom: var(--rule); }
.pillar:not(:nth-child(3n+1)) { padding-left: 2rem; border-left: var(--rule); }
.pillar .num { font-weight: 600; font-size: var(--text-label); letter-spacing: .12em; color: var(--btc-graphite); display: block; margin-bottom: 1.25rem; }
.pillar p { margin: .75rem 0 0; font-size: 1rem; }
@media (max-width: 860px) {
  .pillars { grid-template-columns: 1fr 1fr; }
  .pillar, .pillar:not(:nth-child(3n+1)) { padding: 1.75rem 1.5rem 2rem 0; border-left: 0; }
  .pillar:nth-child(2n) { padding-left: 1.5rem; border-left: var(--rule); }
}
@media (max-width: 560px) {
  .pillars { grid-template-columns: 1fr; }
  .pillar:nth-child(2n) { padding-left: 0; border-left: 0; }
}

/* Products */
.products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
@media (max-width: 960px) { .products { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .products { grid-template-columns: 1fr; } }
.card { background: var(--btc-ivory); border: var(--rule); border-radius: var(--radius); display: flex; flex-direction: column; }
.card .cover { aspect-ratio: 4 / 3; padding: 7% 8%; }
.card .cover-logo { width: 26%; }
.card .cover-title { font-size: 11cqi; }
.card .cover-rule { margin: 4cqi 0 3cqi; }
.card .cover-label { font-size: 2.6cqi; }
.card .cover::after { font-size: 90cqi; top: -8%; right: -6%; }
.card-body { padding: 1.5rem 1.5rem 1.75rem; display: flex; flex-direction: column; flex: 1; }
.card-type { font-weight: 600; font-size: .75rem; letter-spacing: .12em; text-transform: uppercase; color: var(--btc-graphite); display: flex; justify-content: space-between; margin-bottom: .75rem; }
.card-type .badge { background: var(--btc-charcoal); color: var(--btc-ivory); padding: 3px 8px; }
.card h3 { font-size: 1.75rem; }
.card p { font-size: 1rem; margin: .75rem 0 1rem; }
.card ul { list-style: none; padding: 0; margin: 0 0 1.5rem; font-size: .9375rem; color: var(--btc-charcoal); }
.card li { padding: .4rem 0; border-top: var(--rule); }
.card-foot { margin-top: auto; display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.price { font-family: var(--font-display); font-size: 2.25rem; line-height: 1; }
.card .btn { padding: 13px 20px; }
.card.featured { background: var(--btc-charcoal); color: var(--btc-ivory); border-color: var(--btc-charcoal); }
.card.featured p { color: var(--btc-greige); }
.card.featured ul { color: var(--btc-ivory); }
.card.featured li { border-color: var(--btc-soft-charcoal); }
.card.featured .card-type { color: var(--btc-stone); }
.card.featured .card-type .badge { background: var(--btc-ivory); color: var(--btc-charcoal); }
.card.featured .cover { background: var(--btc-soft-charcoal); }
.card.featured .cover::after { color: var(--btc-graphite); }
.card.featured .btn { background: var(--btc-ivory); color: var(--btc-charcoal); }
.card.featured .btn:hover { background: var(--btc-greige); }
.shop-note { margin-top: 2rem; font-size: var(--text-small); color: var(--btc-graphite); }

/* About */
.about-grid { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); gap: clamp(2.5rem, 7vw, 6rem); align-items: center; }
@media (max-width: 860px) { .about-grid { grid-template-columns: 1fr; } }
.about-img { aspect-ratio: 4 / 5; object-fit: cover; width: 100%; height: auto; }
@media (max-width: 860px) { .about-img { aspect-ratio: 4 / 3; } }
.principles { list-style: none; padding: 0; margin: 2rem 0 0; display: grid; gap: 0; }
.principles li { display: grid; grid-template-columns: 3rem 1fr; padding: 1rem 0; border-top: var(--rule); font-size: 1rem; color: var(--btc-charcoal); }
.principles li:last-child { border-bottom: var(--rule); }
.principles span { font-weight: 600; font-size: var(--text-label); letter-spacing: .12em; color: var(--btc-graphite); padding-top: .2rem; }

/* Final CTA */
.cta { overflow: hidden; }
.cta .quote-mark { font-family: var(--font-display); font-size: 9rem; line-height: .6; color: var(--btc-stone); display: block; height: 4rem; }
.cta h2 { max-width: 14ch; }
.cta .big-letter { position: absolute; right: -4vw; bottom: -10vw; font-family: var(--font-display); font-size: clamp(20rem, 48vw, 44rem); line-height: .8; color: var(--btc-soft-charcoal); pointer-events: none; user-select: none; }
.cta .wrap { position: relative; }
.cta form { margin-top: 2.25rem; }

/* Footer */
.footer { background: var(--btc-charcoal); color: var(--btc-greige); padding: 4rem 0 2.5rem; border-top: 1px solid var(--btc-soft-charcoal); font-size: var(--text-small); }
.footer-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 2rem; flex-wrap: wrap; padding-bottom: 2.5rem; border-bottom: 1px solid var(--btc-soft-charcoal); }
.footer-brand { display: flex; align-items: center; gap: 1.25rem; }
.footer-brand img { width: 80px; height: auto; }
.footer-brand strong { display: block; font-family: var(--font-display); font-weight: 400; font-size: 1.5rem; color: var(--btc-ivory); letter-spacing: .01em; }
.footer-links { display: flex; gap: 1.75rem; list-style: none; margin: 0; padding: 0; flex-wrap: wrap; }
.footer-links a { color: var(--btc-greige); text-decoration: none; font-weight: 500; }
.footer-links a:hover { color: var(--btc-ivory); text-decoration: underline; }
.footer-legal { padding-top: 2rem; color: var(--btc-stone); font-size: .8125rem; display: grid; gap: .75rem; }
.footer-legal p { max-width: 80ch; margin: 0; color: var(--btc-stone); }

/* Simple pages (thank you, success, legal) */
.page-hero { padding: clamp(4rem, 10vw, 7rem) 0 clamp(3rem, 6vw, 4rem); }
.page-hero h1 { font-size: clamp(3rem, 8vw, 6rem); max-width: 14ch; }
.page-body { padding: clamp(3rem, 7vw, 5rem) 0 var(--space-section); }
.reading { max-width: var(--reading-width); }
.reading h2 { font-size: 2rem; margin: 2.5rem 0 .75rem; }
.reading p, .reading li { color: var(--btc-graphite); }
.downloads { list-style: none; padding: 0; margin: 1.5rem 0 2rem; max-width: 640px; }
.downloads li { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1.1rem 0; border-top: var(--rule); flex-wrap: wrap; }
.downloads li:last-child { border-bottom: var(--rule); }
.downloads strong { font-family: var(--font-display); font-weight: 400; font-size: 1.6rem; text-transform: uppercase; line-height: 1; }
.notice { border-left: 3px solid var(--btc-charcoal); padding: 1rem 1.25rem; background: var(--btc-ivory); color: var(--btc-charcoal); max-width: 640px; font-size: 1rem; }
.skeleton { height: 64px; background: var(--btc-ivory); animation: sk 1.2s infinite ease-in-out alternate; margin: .5rem 0; max-width: 640px; }
@keyframes sk { to { opacity: .45; } }