@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&display=swap');

/* ── DESIGN SYSTEM ─────────────────────────────────────── */
:root {
  --accent:        #00FF41;
  --accent-dim:    rgba(0,255,65,0.08);
  --accent-border: rgba(0,255,65,0.28);

  --fg:   #edecea;
  --fg-2: rgba(237,236,234,0.65);
  --fg-3: rgba(237,236,234,0.45);

  --bg:        #0b0b0b;
  --bg-raised: rgba(255,255,255,0.025);

  --border:   rgba(255,255,255,0.08);
  --border-2: rgba(255,255,255,0.15);

  --max:   1100px;
  --mono:  'SF Mono','Fira Code',ui-monospace,monospace;
  --sans:  'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  --nav-h: 60px;
}

/* ── SCROLL ─────────────────────────────────────────────── */
html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-h);
  scroll-snap-type: y proximity;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; scroll-snap-type: none; }
}

.snap-section {
  scroll-snap-align: start;
}

/* Sections with enough content to warrant full-viewport height */
#hero, #context, #applications, #contact {
  min-height: 100svh;
}

/* Non-hero sections: center content below fixed nav */
#context, #applications, #contact {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--nav-h) + 40px) 0 48px;
}

/* Ownership has little content — no forced viewport height */
#ownership {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: auto;
  padding: calc(var(--nav-h) + 80px) 0 100px;
}

/* ── RESET ──────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 18px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
button { cursor: pointer; border: none; background: none; font: inherit; color: inherit; }
ul { list-style: none; }

/* ── LAYOUT ─────────────────────────────────────────────── */
.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 48px;
  width: 100%;
}

/* ── NAVIGATION ─────────────────────────────────────────── */
#nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  border-bottom: 1px solid var(--border);
  background: rgba(11,11,11,0.94);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.nav-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 48px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.nav-wordmark {
  font-family: var(--mono);
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  color: var(--fg);
  flex-shrink: 0;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
  flex: 1;
  justify-content: center;
}
.nav-links a {
  font-size: 0.875rem;
  color: var(--fg-2);
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--accent); }
.nav-cta {
  padding: 8px 20px;
  border: 1px solid var(--border-2);
  font-size: 0.875rem;
  color: var(--fg);
  flex-shrink: 0;
  transition: border-color 0.2s, color 0.2s;
}
.nav-cta:hover { border-color: var(--accent); color: var(--accent); }
a:focus-visible, button:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 2px;
}

/* mobile hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 22px;
  height: 16px;
  cursor: pointer;
}
.hamburger span {
  display: block;
  height: 1px;
  background: var(--fg);
  transition: transform 0.25s, opacity 0.25s;
}
.hamburger.open span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }

.nav-mobile {
  display: none;
  position: fixed;
  top: var(--nav-h);
  left: 0; right: 0;
  background: rgba(11,11,11,0.98);
  border-bottom: 1px solid var(--border);
  padding: 28px 24px 32px;
  flex-direction: column;
  z-index: 99;
}
.nav-mobile.open { display: flex; }
.nav-mobile a {
  font-size: 1.0625rem;
  color: var(--fg-2);
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}
.nav-mobile a.mob-cta {
  color: var(--accent);
  border-bottom: none;
  margin-top: 10px;
}

/* ── SHARED TYPOGRAPHY ──────────────────────────────────── */
.section-label {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  display: block;
  margin-bottom: 16px;
}
/* For labels containing brand name — preserves DecisionOS casing */
.section-label-plain {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--accent);
  display: block;
  margin-bottom: 16px;
}
.h2 {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 500;
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin-bottom: 18px;
}
.body-text {
  font-size: 1.0625rem;
  color: var(--fg-2);
  line-height: 1.72;
}
.btn-primary {
  display: inline-block;
  padding: 13px 30px;
  background: var(--fg);
  color: var(--bg);
  font-size: 1rem;
  font-weight: 500;
  transition: opacity 0.2s;
}
.btn-primary:hover { opacity: 0.88; }
.btn-ghost {
  font-size: 1rem;
  color: var(--fg-2);
  transition: color 0.2s;
}
.btn-ghost:hover { color: var(--fg); }

/* ── SCROLL HINT ────────────────────────────────────────── */
.scroll-hint {
  position: absolute;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  color: rgba(237,236,234,0.28);
  pointer-events: none;
}

/* ── SECTION 1: HERO ────────────────────────────────────── */
#hero {
  padding-top: var(--nav-h);
  display: flex;
  align-items: center;
  position: relative;
}
.hero-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 56px 48px;
  width: 100%;
  display: grid;
  grid-template-columns: 55% 1fr;
  gap: 64px;
  align-items: center;
}
.hero-eyebrow {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 22px;
  display: block;
}
.hero-h1 {
  font-size: clamp(2.25rem, 4.5vw, 3.5rem);
  font-weight: 500;
  line-height: 1.12;
  letter-spacing: -0.025em;
  margin-bottom: 22px;
}
.hero-sub {
  font-size: 1.125rem;
  color: var(--fg-2);
  line-height: 1.72;
  max-width: 480px;
  margin-bottom: 40px;
}
.hero-ctas {
  display: flex;
  align-items: center;
  gap: 28px;
  flex-wrap: wrap;
}

/* hero model diagram */
.model-stack { display: flex; flex-direction: column; }
.model-layer {
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: 16px;
  padding: 20px 24px;
  border: 1px solid var(--border-2);
  background: var(--bg-raised);
  position: relative;
}
.model-layer + .model-layer { margin-top: 14px; }
.model-layer:not(:last-child)::after {
  content: '';
  position: absolute;
  bottom: -14px;
  left: 38px;
  width: 1px;
  height: 14px;
  background: var(--border-2);
}
.model-num {
  font-family: var(--mono);
  font-size: 0.625rem;
  color: var(--accent);
  padding-top: 4px;
}
.model-title {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--fg);
}
.model-tags {
  font-family: var(--mono);
  font-size: 0.6875rem;
  color: var(--fg-3);
  letter-spacing: 0.02em;
  line-height: 1.6;
}

/* ── SECTION 2: CONTEXT ─────────────────────────────────── */
.context-layout {
  display: grid;
  grid-template-columns: 52% 1fr;
  gap: 64px;
  align-items: start;
}

/* flow visual */
.flow-block { margin-top: 28px; }
.flow-track { margin-bottom: 20px; }
.flow-track-label {
  font-family: var(--mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(237,236,234,0.72);
  margin-bottom: 12px;
  display: block;
}
.flow-nodes {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
}
.flow-node {
  font-size: 0.875rem;
  padding: 7px 14px;
  border: 1px solid var(--border-2);
  color: var(--fg);
  white-space: nowrap;
  line-height: 1;
}
.flow-node.hi {
  color: var(--accent);
  border-color: var(--accent-border);
  background: var(--accent-dim);
}
.flow-node.outcome {
  border-color: rgba(255,255,255,0.32);
  font-weight: 500;
}
.flow-arrow {
  font-size: 0.75rem;
  color: rgba(237,236,234,0.50);
  flex-shrink: 0;
}
.flow-divider {
  width: 100%;
  height: 1px;
  background: var(--border-2);
  margin: 20px 0;
}
.flow-takeaway {
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--fg);
  line-height: 1.45;
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid rgba(0,255,65,0.22);
}

/* context right: compact model items */
.context-model {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  margin-top: 34px;
}
.context-model-item {
  display: grid;
  grid-template-columns: 28px 1fr;
  gap: 14px;
  padding: 20px 22px;
  border-bottom: 1px solid var(--border);
}
.context-model-item:last-child { border-bottom: none; }
.cmi-num {
  font-family: var(--mono);
  font-size: 0.625rem;
  color: var(--accent);
  padding-top: 3px;
}
.cmi-title {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 5px;
  color: var(--fg);
}
.cmi-body {
  font-size: 0.9375rem;
  color: var(--fg-2);
  line-height: 1.6;
}

/* ── SECTION 3: APPLICATIONS ────────────────────────────── */
.apps-intro { margin-bottom: 28px; }
.apps-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.app-card {
  border: 1px solid var(--border-2);
  padding: 30px 28px;
  background: var(--bg-raised);
}
.app-tag {
  font-family: var(--mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
  display: block;
}
.app-title {
  font-size: 1.1875rem;
  font-weight: 500;
  margin-bottom: 12px;
  line-height: 1.25;
}
.app-body {
  font-size: 0.9375rem;
  color: var(--fg-2);
  line-height: 1.68;
  margin-bottom: 18px;
}
.app-flow {
  padding: 16px 18px;
  border: 1px solid var(--border);
  background: rgba(0,0,0,0.3);
  margin-bottom: 16px;
}
.app-flow-label {
  font-family: var(--mono);
  font-size: 0.5625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fg-3);
  margin-bottom: 10px;
  display: block;
}
.app-flow-nodes {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 5px;
}
.app-node {
  font-family: var(--mono);
  font-size: 0.75rem;
  padding: 5px 11px;
  border: 1px solid var(--border-2);
  color: rgba(237,236,234,0.85);
  white-space: nowrap;
  line-height: 1;
}
.app-node.key {
  border-color: var(--accent-border);
  color: var(--accent);
  background: var(--accent-dim);
}
.app-arrow { font-size: 0.625rem; color: var(--fg-3); }
.app-factors-label {
  font-family: var(--mono);
  font-size: 0.5625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(237,236,234,0.60);
  margin-bottom: 9px;
  display: block;
}
.app-factors {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.app-factor {
  font-family: var(--mono);
  font-size: 0.6875rem;
  color: rgba(237,236,234,0.68);
  padding: 4px 10px;
  border: 1px solid rgba(255,255,255,0.12);
  line-height: 1;
}
.app-note {
  font-size: 1rem;
  font-weight: 500;
  color: var(--fg);
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid rgba(0,255,65,0.22);
  line-height: 1.5;
}

/* ── SECTION 4: DATA OWNERSHIP ──────────────────────────── */
.ownership-solo {
  max-width: 640px;
}
.ownership-body {
  font-size: 1.0625rem;
  color: var(--fg-2);
  line-height: 1.78;
  margin-bottom: 28px;
}
.ownership-highlight {
  border-left: 2px solid var(--accent);
  padding: 4px 0 4px 18px;
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--fg);
  line-height: 1.5;
}

/* ── SECTION 5: CONTACT ─────────────────────────────────── */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 64px;
  align-items: start;
}
.contact-sub {
  font-size: 1.0625rem;
  color: var(--fg-2);
  line-height: 1.72;
  margin-bottom: 32px;
}
.contact-email-label {
  font-family: var(--mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fg-3);
  margin-bottom: 7px;
  display: block;
}
.contact-email a {
  font-family: var(--mono);
  font-size: 1rem;
  color: var(--fg);
  transition: color 0.2s;
}
.contact-email a:hover { color: var(--accent); }

/* form */
#contact-form { display: flex; flex-direction: column; gap: 14px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.form-field { display: flex; flex-direction: column; gap: 6px; }
.form-field label {
  font-family: var(--mono);
  font-size: 0.5625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fg-3);
}
.form-field input,
.form-field textarea {
  background: transparent;
  border: 1px solid var(--border-2);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 1rem;
  padding: 12px 14px;
  outline: none;
  transition: border-color 0.2s;
  width: 100%;
  -webkit-appearance: none;
  border-radius: 0;
}
.form-field input::placeholder,
.form-field textarea::placeholder { color: var(--fg-3); }
.form-field input:focus,
.form-field textarea:focus { border-color: var(--accent-border); }
.form-field textarea {
  resize: vertical;
  min-height: 110px;
  line-height: 1.6;
}
.form-submit {
  padding: 13px 30px;
  background: var(--fg);
  color: var(--bg);
  font-size: 1rem;
  font-weight: 500;
  font-family: var(--sans);
  border: none;
  cursor: pointer;
  transition: opacity 0.2s;
  align-self: flex-start;
}
.form-submit:hover { opacity: 0.88; }
.form-submit:disabled { opacity: 0.45; cursor: not-allowed; }
.form-status {
  font-size: 0.9375rem;
  padding: 11px 14px;
  border: 1px solid var(--border);
  display: none;
  line-height: 1.5;
}
.form-status.success { color: #6fcf97; border-color: rgba(111,207,151,0.2); display: block; }
.form-status.error   { color: #eb7070; border-color: rgba(235,112,112,0.2); display: block; }

/* ── FOOTER ─────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  padding: 26px 0;
}
.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-wordmark {
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--fg-3);
}
.footer-meta {
  display: flex;
  align-items: center;
  gap: 22px;
}
.footer-meta a {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--fg-3);
  transition: color 0.2s;
}
.footer-meta a:hover { color: var(--fg-2); }
.footer-copy {
  font-family: var(--mono);
  font-size: 0.625rem;
  color: var(--fg-3);
  opacity: 0.5;
}

/* ── REVEAL ─────────────────────────────────────────────── */
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.45s ease, transform 0.45s ease;
  }
  .reveal.in { opacity: 1; transform: none; }
}

/* ── RESPONSIVE ─────────────────────────────────────────── */
@media (max-width: 960px) {
  .hero-inner     { grid-template-columns: 1fr; gap: 44px; padding: 48px 40px; }
  .hero-h1        { font-size: clamp(2rem, 5vw, 3rem); }
  .context-layout { grid-template-columns: 1fr; gap: 36px; }
  .context-model  { margin-top: 0; }
  .contact-layout { grid-template-columns: 1fr; gap: 40px; }
}

@media (max-width: 820px) {
  .apps-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root { --nav-h: 56px; }
  .container { padding: 0 24px; }
  .nav-inner  { padding: 0 24px; }
  #context, #applications, #ownership, #contact {
    padding: calc(var(--nav-h) + 28px) 0 36px;
    justify-content: flex-start;
  }
  .hero-inner { padding: 36px 24px; }
  .footer-inner { padding: 0 24px; }
}

@media (max-width: 620px) {
  .diff-item     { grid-template-columns: 1fr; }
  .diff-pattern  {
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding-bottom: 12px;
    color: var(--fg-3);
  }
  .diff-pattern::before {
    content: 'Common pattern';
    font-family: var(--mono);
    font-size: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--fg-3);
    display: block;
    margin-bottom: 5px;
  }
  .diff-approach::before {
    content: 'DecisionOS';
    font-family: var(--mono);
    font-size: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--accent);
    display: block;
    margin-bottom: 5px;
  }
  .form-row       { grid-template-columns: 1fr; }
  .footer-inner   { flex-direction: column; align-items: flex-start; gap: 10px; }
  .footer-meta    { flex-direction: column; align-items: flex-start; gap: 6px; }
}