/* ============================================================
   MIM v2 — "Receipts" design system
   Editorial paper + engineering ledger. Every visual is a real
   artifact; every number carries a provenance line.
   Light root theme = A "Field Notes" · html.night = B "Night Ledger"
   ============================================================ */

/* ---------- tokens ---------- */
:root {
  --paper: #FAF7F2;
  --paper-raise: #FFFFFF;
  --ink: #1A1915;
  --ink-2: #46433C;
  --ink-3: #8A857B;
  --line: #E2DCCF;
  --line-strong: #1A1915;
  --accent: #1E6E4E;
  --accent-ink: #0F4A33;
  --accent-wash: #EAF2ED;
  --terminal: #141614;
  --terminal-raise: #1C1F1C;
  --terminal-ink: #D7E4DA;
  --terminal-dim: #7E8F84;
  --terminal-ok: #5DD39E;
  --terminal-line: #2A2E2A;
  --warn: #B4690E;

  --serif: 'Fraunces', Georgia, 'Times New Roman', serif;
  --sans: 'IBM Plex Sans', system-ui, -apple-system, sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, 'Cascadia Mono', Consolas, monospace;

  --t-hero: clamp(2.5rem, 1rem + 5.4vw, 4.75rem);
  --t-h2: clamp(1.8rem, 1rem + 2.6vw, 2.75rem);
  --t-h3: 1.2rem;
  --t-body: 1.0625rem;
  --t-small: 0.9rem;
  --t-mono: 0.8125rem;
  --t-label: 0.72rem;

  --w-page: 1120px;
  --w-prose: 40rem;
  --sp-section: clamp(4.5rem, 3rem + 6vw, 8.5rem);
  --sp-gap: clamp(1.5rem, 1rem + 2vw, 3rem);

  --r-btn: 4px;
  --r-art: 2px;

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

/* Night Ledger (B): near-black editorial, mono-forward, ruled */
html.night {
  --paper: #111311;
  --paper-raise: #171A17;
  --ink: #EDEAE2;
  --ink-2: #B9B5AA;
  --ink-3: #7D796F;
  --line: #262A26;
  --line-strong: #EDEAE2;
  --accent: #5DD39E;
  --accent-ink: #8FE4BC;
  --accent-wash: #16241D;
  --terminal: #0B0D0B;
  --terminal-raise: #141714;
  --terminal-line: #242824;
}

/* ---------- base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink-2);
  font-family: var(--sans);
  font-size: var(--t-body);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
/* B: faint ruled-ledger baseline grid — fixed viewport-sized layer (cheap to paint) */
html.night body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    to bottom, transparent 0, transparent 31px, rgba(237, 234, 226, 0.045) 31px, rgba(237, 234, 226, 0.045) 32px);
}
::selection { background: var(--accent); color: var(--paper); }
a { color: inherit; }
img { max-width: 100%; display: block; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

h1, h2 { font-family: var(--serif); font-weight: 420; color: var(--ink); line-height: 1.06; margin: 0; letter-spacing: -0.01em; }
h1 { font-size: var(--t-hero); font-variation-settings: 'opsz' 90; }
h2 { font-size: var(--t-h2); font-variation-settings: 'opsz' 60; }
h3 { font-family: var(--sans); font-weight: 600; font-size: var(--t-h3); color: var(--ink); margin: 0 0 0.4rem; line-height: 1.3; }
em { font-style: italic; }
h1 em, h2 em { font-variation-settings: 'opsz' 90, 'wght' 340; font-style: italic; }

.wrap { max-width: var(--w-page); margin: 0 auto; padding: 0 clamp(1.25rem, 4vw, 2.5rem); }
.prose { max-width: var(--w-prose); }

.eyebrow {
  font-family: var(--mono); font-size: var(--t-label); font-weight: 500;
  letter-spacing: 0.14em; text-transform: uppercase; color: var(--accent);
  display: flex; align-items: center; gap: 0.6rem; margin: 0 0 1.1rem;
}
.eyebrow::before { content: ''; width: 1.75rem; height: 1px; background: var(--accent); flex: none; }
.eyebrow--plain::before { display: none; }

.mono { font-family: var(--mono); font-size: var(--t-mono); }
.small { font-size: var(--t-small); }
.muted { color: var(--ink-3); }

/* ---------- header ---------- */
.site-head {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 92%, transparent);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line);
  view-transition-name: site-head;
}
.site-head .wrap { display: flex; align-items: center; gap: 2rem; height: 4rem; }
.brand { font-family: var(--mono); font-weight: 500; font-size: 0.95rem; letter-spacing: 0.02em; color: var(--ink); text-decoration: none; view-transition-name: brand; }
.brand b { color: var(--accent); font-weight: 500; }
.nav { display: flex; gap: 1.6rem; margin-left: auto; align-items: center; }
.nav a { font-size: 0.92rem; font-weight: 500; color: var(--ink-2); text-decoration: none; }
.nav a:hover { color: var(--ink); }
.nav a.is-cta {
  font-family: var(--mono); font-size: 0.82rem; color: var(--paper); background: var(--ink);
  padding: 0.5rem 0.95rem; border-radius: var(--r-btn);
}
.nav a.is-cta:hover { background: var(--accent-ink); color: #fff; }
html.night .nav a.is-cta { color: var(--paper); background: var(--ink); }
html.night .nav a.is-cta:hover { background: var(--accent); color: #0B0D0B; }
.nav-toggle { display: none; }

/* scroll progress rule under header */
@supports (animation-timeline: scroll()) {
  @media (prefers-reduced-motion: no-preference) {
    .site-head::after {
      content: ''; position: absolute; left: 0; bottom: -1px; height: 2px; width: 100%;
      background: var(--accent); transform-origin: 0 50%; transform: scaleX(0);
      animation: head-progress linear both; animation-timeline: scroll(root);
    }
    @keyframes head-progress { to { transform: scaleX(1); } }
  }
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 0.55rem;
  font-family: var(--sans); font-weight: 600; font-size: 0.98rem; text-decoration: none;
  padding: 0.85rem 1.5rem; border-radius: var(--r-btn);
  transition: transform 180ms var(--ease-out), background 180ms var(--ease-out), color 180ms var(--ease-out);
}
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { background: var(--accent-ink); color: #fff; transform: translateY(-1px); }
html.night .btn-primary:hover { background: var(--accent); color: #0B0D0B; }
.btn-ghost { border: 1px solid var(--line); color: var(--ink); background: transparent; }
.btn-ghost:hover { border-color: var(--ink); transform: translateY(-1px); }
.btn .tick { font-family: var(--mono); color: var(--accent); }
.btn-primary .tick { color: var(--terminal-ok); }

/* ---------- sections ---------- */
.section { padding: var(--sp-section) 0; border-top: 1px solid var(--line); }
.section--flush { border-top: 0; }
.section-head { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; margin-bottom: calc(var(--sp-gap) * 1.1); flex-wrap: wrap; }
.section-head .index { font-family: var(--mono); font-size: var(--t-mono); color: var(--ink-3); }

/* ---------- hero ---------- */
.hero { padding: calc(var(--sp-section) * 0.9) 0 var(--sp-section); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(2rem, 5vw, 4.5rem); align-items: start; }
.hero h1 { view-transition-name: page-title; margin: 0 0 1.4rem; }
.hero .lede { font-size: clamp(1.05rem, 1rem + 0.5vw, 1.2rem); max-width: 34rem; margin: 0 0 2.2rem; }
.hero-ctas { display: flex; gap: 0.9rem; flex-wrap: wrap; align-items: center; }
.hero-note { margin-top: 1.1rem; }

/* ---------- artifact (terminal surfaces) ---------- */
.artifact {
  background: var(--terminal); color: var(--terminal-ink);
  border: 1px solid var(--terminal-line); border-radius: var(--r-art);
  font-family: var(--mono); font-size: var(--t-mono); line-height: 1.6;
}
html.night .artifact { border-color: var(--line); }
.artifact-bar {
  display: flex; align-items: center; gap: 0.6rem;
  padding: 0.6rem 1rem; border-bottom: 1px solid var(--terminal-line);
  color: var(--terminal-dim); font-size: var(--t-label); letter-spacing: 0.1em; text-transform: uppercase;
}
.artifact-bar .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--terminal-ok); flex: none; }
.artifact-bar .dot--pulse { animation: none; }
@media (prefers-reduced-motion: no-preference) {
  .artifact-bar .dot--pulse { animation: dot-pulse 2.4s ease-in-out infinite; }
  @keyframes dot-pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.35; } }
}
.artifact-body { padding: 1.1rem 1.2rem 1.2rem; }

/* call transcript */
.artifact-call .turn { display: grid; grid-template-columns: 4.6rem 1fr auto; gap: 0.75rem; padding: 0.45rem 0; align-items: baseline; }
.artifact-call .turn + .turn { border-top: 1px dashed var(--terminal-line); }
.artifact-call .who { color: var(--terminal-dim); font-size: var(--t-label); letter-spacing: 0.08em; }
.artifact-call .who.ai { color: var(--terminal-ok); }
.artifact-call .ts { color: var(--terminal-dim); font-size: var(--t-label); }
.artifact-caption {
  font-family: var(--mono); font-size: var(--t-label); color: var(--ink-3);
  letter-spacing: 0.04em; margin-top: 0.7rem; line-height: 1.6;
}

/* ---------- stats / receipts ledger ---------- */
.receipts { border-top: 1px solid var(--line-strong); }
.stat-ledger { border-top: 1px solid var(--line); }
.stat-row {
  display: grid; grid-template-columns: minmax(9rem, 15rem) 1fr minmax(0, 18rem);
  gap: 1.25rem; align-items: baseline; padding: 1.35rem 0;
  border-bottom: 1px solid var(--line);
}
.stat-row .value { font-family: var(--serif); font-size: clamp(1.9rem, 1.3rem + 2vw, 2.9rem); font-weight: 460; color: var(--ink); line-height: 1; font-variation-settings: 'opsz' 40; white-space: nowrap; }
.stat-row .label { font-size: var(--t-body); color: var(--ink-2); }
.stat-row .label b { color: var(--ink); font-weight: 600; }
.stat-provenance { font-family: var(--mono); font-size: var(--t-label); color: var(--ink-3); letter-spacing: 0.04em; text-align: right; }
.stat-provenance .nb { white-space: nowrap; }
.stat-provenance::before { content: '⌖ '; color: var(--accent); }
.receipts-note { margin-top: 1.4rem; }

/* live status chip */
.live-chip { display: inline-flex; align-items: center; gap: 0.5rem; font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent-ink); background: var(--accent-wash); border: 1px solid color-mix(in srgb, var(--accent) 30%, transparent); padding: 0.35rem 0.7rem; border-radius: 3px; }
.live-chip .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }
@media (prefers-reduced-motion: no-preference) { .live-chip .dot { animation: dot-pulse 2.4s ease-in-out infinite; } }

/* ---------- service ledger ---------- */
.svc { border-bottom: 1px solid var(--line); padding: 2rem 0; display: grid; grid-template-columns: 3.2rem minmax(0, 17rem) 1fr; gap: 1.25rem 2rem; align-items: start; text-decoration: none; transition: background 200ms var(--ease-out); }
.svc:first-of-type { border-top: 1px solid var(--line); }
.svc:hover { background: color-mix(in srgb, var(--accent-wash) 55%, transparent); }
.svc .num { font-family: var(--mono); font-size: var(--t-mono); color: var(--ink-3); padding-top: 0.35rem; }
.svc h3 { margin: 0; }
.svc .stack { font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.06em; color: var(--ink-3); margin-top: 0.5rem; }
.svc .stack b { color: var(--accent-ink); font-weight: 500; }
html.night .svc .stack b { color: var(--accent); }
.svc p { margin: 0; max-width: 38rem; }
.svc .go { font-family: var(--mono); font-size: var(--t-mono); color: var(--accent-ink); margin-top: 0.6rem; display: inline-block; }
html.night .svc .go { color: var(--accent); }

/* ---------- process steps ---------- */
.steps { counter-reset: step; display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.step { counter-increment: step; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: 1.6rem 1.4rem 1.8rem; }
.step::before { content: '0' counter(step); font-family: var(--mono); font-size: var(--t-mono); color: var(--accent); display: block; margin-bottom: 0.9rem; }
.step h3 { font-size: 1.05rem; }
.step p { margin: 0; font-size: var(--t-small); }

/* ---------- build log ---------- */
.build-log { border-top: 1px solid var(--line); }
.build-log .entry { display: grid; grid-template-columns: 8.5rem 1fr; gap: 1.5rem; padding: 0.85rem 0; border-bottom: 1px solid var(--line); font-size: var(--t-small); }
.build-log .date { font-family: var(--mono); font-size: var(--t-mono); color: var(--ink-3); white-space: nowrap; }
.build-log .entry p { margin: 0; }

/* ---------- marketing band ---------- */
.band { background: var(--paper-raise); border-top: 1px solid var(--line); }
html.night .band { background: var(--terminal-raise); }
.band-links { display: flex; gap: 1.75rem; flex-wrap: wrap; margin-top: 1.5rem; }
.band-links a { font-family: var(--mono); font-size: var(--t-mono); color: var(--ink); text-decoration: none; border-bottom: 1px solid var(--line-strong); padding-bottom: 2px; }
.band-links a:hover { color: var(--accent-ink); border-color: var(--accent-ink); }
html.night .band-links a:hover { color: var(--accent); border-color: var(--accent); }

/* ---------- final CTA ---------- */
.cta-final { text-align: left; }
.cta-final h2 { max-width: 22ch; }
.cta-final .lede { max-width: 36rem; }

/* ---------- footer ---------- */
.site-foot { border-top: 1px solid var(--line-strong); padding: 3rem 0 3.5rem; font-size: var(--t-small); }
.foot-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 2.5rem; }
.foot-grid h4 { font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-3); margin: 0 0 0.9rem; font-weight: 500; }
.foot-grid ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.45rem; }
.foot-grid a { text-decoration: none; color: var(--ink-2); }
.foot-grid a:hover { color: var(--ink); }
.honesty { border: 1px solid var(--line); border-left: 3px solid var(--accent); padding: 1rem 1.25rem; margin-top: 2.75rem; font-size: var(--t-small); color: var(--ink-2); max-width: 46rem; }
.honesty b { color: var(--ink); }
.foot-legal { margin-top: 2rem; display: flex; gap: 1.5rem; flex-wrap: wrap; font-family: var(--mono); font-size: var(--t-label); color: var(--ink-3); }
.foot-legal a { color: inherit; }

/* ---------- motion: view transitions + scroll reveal ---------- */
@view-transition { navigation: auto; }
@media (prefers-reduced-motion: no-preference) {
  ::view-transition-old(root) { animation-duration: 180ms; }
  ::view-transition-new(root) { animation-duration: 220ms; }
}
@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .settle { animation: settle both ease-out; animation-timeline: view(); animation-range: entry 0% entry 34%; }
    @keyframes settle { from { opacity: 0.001; transform: translateY(16px); } to { opacity: 1; transform: none; } }
  }
}

/* ---------- split layout ---------- */
.split { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 4fr); gap: clamp(2rem, 4vw, 4rem); align-items: start; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; } }

/* ---------- forms (paper theme) ---------- */
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.1rem; }
.field { display: flex; flex-direction: column; gap: 0.4rem; }
.field--full { grid-column: 1 / -1; }
.field label { font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-2); }
.field input, .field select, .field textarea {
  font-family: var(--sans); font-size: var(--t-body); color: var(--ink);
  background: var(--paper-raise); border: 1px solid var(--line); border-radius: var(--r-btn);
  padding: 0.75rem 0.9rem; width: 100%;
}
.field input:focus, .field select:focus, .field textarea:focus { outline: 2px solid var(--accent); outline-offset: 0; border-color: var(--accent); }
.consent { display: flex; align-items: flex-start; gap: 0.7rem; font-size: 0.78rem; color: var(--ink-3); line-height: 1.55; }
.consent input { margin-top: 0.2rem; accent-color: var(--accent); }
.consent a { color: var(--accent-ink); }
.form-banner { border: 1px solid var(--line); border-left: 3px solid var(--accent); padding: 0.9rem 1.1rem; font-size: var(--t-small); margin-bottom: 1.25rem; }
.form-banner.error { border-left-color: var(--warn); }
.hidden { display: none; }
.contact-aside { border: 1px solid var(--line); padding: 1.5rem; display: grid; gap: 1.1rem; align-content: start; }
.contact-aside h3 { font-size: 1rem; }
.contact-aside .row { display: grid; gap: 0.15rem; font-size: var(--t-small); }
.contact-aside .row b { font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-3); font-weight: 500; }
.contact-aside a { color: var(--accent-ink); text-decoration: none; }
.contact-aside a:hover { text-decoration: underline; }
@media (max-width: 720px) { .form-grid { grid-template-columns: 1fr; } }

/* ---------- chat panel (vanilla) ---------- */
.chat-launch {
  position: fixed; right: 1.25rem; bottom: 1.25rem; z-index: 70;
  font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.1em; text-transform: uppercase;
  background: var(--terminal); color: var(--terminal-ok); border: 1px solid var(--terminal-line);
  padding: 0.7rem 1rem; border-radius: var(--r-btn); cursor: pointer;
}
.chat-launch:hover { border-color: var(--terminal-ok); }
.chat-panel {
  position: fixed; right: 1.25rem; bottom: 4.5rem; z-index: 70;
  width: min(380px, calc(100vw - 2.5rem)); height: min(520px, 70vh);
  display: flex; flex-direction: column;
  background: var(--terminal); color: var(--terminal-ink);
  border: 1px solid var(--terminal-line); border-radius: var(--r-art);
  font-family: var(--mono); font-size: var(--t-mono);
}
.chat-panel[hidden] { display: none; }
.chat-bar {
  display: flex; align-items: center; gap: 0.6rem; padding: 0.6rem 0.9rem;
  border-bottom: 1px solid var(--terminal-line); color: var(--terminal-dim);
  font-size: var(--t-label); letter-spacing: 0.1em; text-transform: uppercase;
}
.chat-bar .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--terminal-ok); flex: none; }
.chat-close { margin-left: auto; background: none; border: 0; color: var(--terminal-dim); font-size: 1.1rem; cursor: pointer; line-height: 1; }
.chat-close:hover { color: var(--terminal-ink); }
.chat-log { flex: 1; overflow-y: auto; padding: 0.9rem; display: flex; flex-direction: column; gap: 0.6rem; }
.chat-msg { max-width: 88%; padding: 0.55rem 0.75rem; border-radius: 3px; line-height: 1.55; white-space: pre-wrap; }
.chat-msg.ai { background: var(--terminal-raise); border: 1px solid var(--terminal-line); align-self: flex-start; }
.chat-msg.user { background: var(--accent-ink); color: #fff; align-self: flex-end; }
.chat-form { display: flex; gap: 0.5rem; padding: 0.7rem; border-top: 1px solid var(--terminal-line); }
.chat-form input {
  flex: 1; background: var(--terminal-raise); border: 1px solid var(--terminal-line); border-radius: 3px;
  color: var(--terminal-ink); font-family: var(--mono); font-size: var(--t-mono); padding: 0.55rem 0.7rem;
}
.chat-form input:focus { outline: 1px solid var(--terminal-ok); outline-offset: 0; }
.chat-form button {
  background: var(--terminal-ok); color: #0B0D0B; border: 0; border-radius: 3px;
  font-family: var(--mono); font-weight: 500; font-size: var(--t-mono); padding: 0.55rem 0.9rem; cursor: pointer;
}
@media print { .chat-launch, .chat-panel { display: none !important; } }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .stat-row { grid-template-columns: minmax(8rem, 12rem) 1fr; }
  .stat-provenance { grid-column: 2; text-align: left; }
  .foot-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 720px) {
  .nav { position: fixed; inset: 4rem 0 auto 0; background: var(--paper); border-bottom: 1px solid var(--line); flex-direction: column; align-items: flex-start; padding: 1.25rem clamp(1.25rem, 4vw, 2.5rem) 1.5rem; gap: 1rem; display: none; }
  .nav.open { display: flex; }
  .nav-toggle { display: inline-flex; margin-left: auto; background: none; border: 1px solid var(--line); border-radius: var(--r-btn); color: var(--ink); font-family: var(--mono); font-size: var(--t-label); letter-spacing: 0.1em; padding: 0.5rem 0.8rem; cursor: pointer; }
  .svc { grid-template-columns: 2.4rem 1fr; }
  .svc p { grid-column: 1 / -1; }
  .steps { grid-template-columns: 1fr; }
  .stat-row { grid-template-columns: 1fr; gap: 0.35rem; }
  .stat-provenance { grid-column: 1; }
  .build-log .entry { grid-template-columns: 1fr; gap: 0.15rem; }
  .foot-grid { grid-template-columns: 1fr; gap: 1.75rem; }
}