/* ─────────────────────────────────────────────────────────────
   TEND · v3 stylesheet
   Cool linen paper, near-black ink, one accent (fountain-pen ink-blue).
   Now with: motion, reveals, a drawing spine, side-in connectors.
   ───────────────────────────────────────────────────────────── */

:root {
  /* paper / ink */
  --paper:       #ECE9E3;
  --paper-card:  #F3F1EB;
  --paper-edge:  #DAD6CC;
  --paper-soft:  #E5E2DB;

  /* ink scale */
  --ink:        #0F1216;
  --ink-soft:   #2A2D33;
  --ink-mute:   #6B6E74;
  --ink-faint:  #9A9D9F;

  /* accent: fountain-pen ink-blue */
  --accent:       #1F4D6B;
  --accent-deep:  #143548;
  --accent-soft:  #5887A8;

  /* diagram-only */
  --moss:    #4A6358;

  /* rules */
  --rule:       #C9C5BB;
  --rule-soft:  #DDD9D1;

  /* type */
  --serif: "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --sans:  "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --mono:  "IBM Plex Mono", ui-monospace, "SFMono-Regular", monospace;

  /* rhythm */
  --col-narrow: 640px;
  --col-mid:    780px;
  --col-wide:   1100px;
  --col-xwide:  1280px;

  /* motion */
  --ease: cubic-bezier(.2,.7,.2,1);
}

/* ─────────────────────── base ─────────────────────── */
* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
}
html { scroll-behavior: smooth; }
body {
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.65;
  font-weight: 400;
  font-feature-settings: "kern" 1, "liga" 1, "ss03" 1;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.005em;
  overflow-x: hidden;
}
::selection { background: var(--accent); color: var(--paper-card); }

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 500;
  letter-spacing: -0.022em;
  color: var(--ink);
  margin: 0;
}
p { margin: 0 0 1.1em 0; }
p:last-child { margin-bottom: 0; }

a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--rule);
  transition: border-color 160ms var(--ease), color 160ms var(--ease);
}
a:hover { border-bottom-color: var(--accent); color: var(--accent-deep); }
em { font-style: italic; }
strong { font-weight: 600; letter-spacing: -0.012em; color: var(--ink); }
b { font-weight: 500; color: var(--ink); }

/* ─────────────────────── spine ─────────────────────── */
.spine {
  position: fixed;
  top: 64px;
  left: max(28px, calc((100vw - var(--col-xwide)) / 2 + 28px));
  width: 4px;
  height: calc(100vh - 96px);
  z-index: 1;
  color: var(--rule);
  pointer-events: none;
  opacity: 0;
  transition: opacity 600ms var(--ease);
}
.spine.lit { opacity: 1; }
.spine path {
  stroke-dasharray: 1000;
  stroke-dashoffset: var(--spine-offset, 1000);
  transition: stroke-dashoffset 80ms linear;
}
@media (max-width: 980px) { .spine { display: none; } }

/* ─────────────────────── header ─────────────────────── */
.site-head {
  position: sticky;
  top: 0;
  z-index: 30;
  background: color-mix(in oklab, var(--paper) 92%, transparent);
  backdrop-filter: saturate(140%) blur(6px);
  -webkit-backdrop-filter: saturate(140%) blur(6px);
  border-bottom: 1px solid var(--rule-soft);
}
.head-inner {
  max-width: var(--col-xwide);
  margin: 0 auto;
  padding: 14px 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 500;
  letter-spacing: -0.015em;
  color: var(--ink);
  border-bottom: none;
  line-height: 1;
}
.wm-mark { width: 18px; height: 18px; color: var(--accent); position: relative; top: 1px; }
.wm-word { color: var(--ink); }

.head-nav { display: flex; gap: 28px; font-family: var(--sans); font-size: 14px; letter-spacing: 0.005em; }
.head-nav a { color: var(--ink-soft); border-bottom: none; padding-bottom: 2px; position: relative; }
.head-nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%; bottom: -2px;
  height: 1px; background: var(--accent);
  transition: right 220ms var(--ease);
}
.head-nav a:hover { color: var(--ink); }
.head-nav a:hover::after { right: 0; }

/* ─────────────────────── reveal animations ─────────────────────── */
.reveal       { opacity: 0; transform: translateY(24px); transition: opacity 720ms var(--ease), transform 720ms var(--ease); }
.reveal.in    { opacity: 1; transform: translateY(0); }

.reveal-side  { opacity: 0; transform: translateX(48px); transition: opacity 800ms var(--ease), transform 800ms var(--ease); }
.reveal-side.in { opacity: 1; transform: translateX(0); }

@media (prefers-reduced-motion: reduce) {
  .reveal, .reveal-side { opacity: 1 !important; transform: none !important; transition: none !important; }
  .ribbon-path, .split-trail { stroke-dashoffset: 0 !important; }
  html { scroll-behavior: auto; }
}

/* ─────────────────────── section scaffolding ─────────────────────── */
section { padding: 130px 56px; position: relative; z-index: 2; }
section > div { max-width: var(--col-xwide); margin: 0 auto; }
.section-label {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--ink-mute);
  margin: 0 0 28px 0;
  display: flex; align-items: center; gap: 14px;
}
.section-label .num { color: var(--accent); font-weight: 500; }
.section-label .rule {
  flex: 0 0 60px;
  height: 1px;
  background: var(--rule);
  display: inline-block;
}

/* ─────────────────────── HERO ─────────────────────── */
.hero { padding: 132px 56px 60px; position: relative; }
.hero-inner { max-width: var(--col-wide); margin: 0 auto; }

.strap {
  font-family: var(--mono);
  font-size: 11.5px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
  margin: 0 0 36px 0;
}
.strap-dot { color: var(--rule); margin: 0 6px; }
.strap-tight { margin-bottom: 18px; }

.hero-h {
  font-size: clamp(58px, 9vw, 132px);
  line-height: 0.96;
  letter-spacing: -0.045em;
  font-weight: 300;
  margin: 0 0 44px 0;
  color: var(--ink);
}
.hero-line-1, .hero-line-2 { display: block; }
.hero-line-2 {
  font-weight: 600;
  color: var(--accent-deep);
  letter-spacing: -0.05em;
}

.hero-sub {
  font-size: clamp(19px, 1.6vw, 22px);
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 54ch;
  margin: 0 0 40px 0;
  letter-spacing: -0.006em;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
  margin-bottom: 64px;
}

.hero-foot {
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.55;
  color: var(--ink-mute);
  max-width: 56ch;
  margin: 0;
  border-top: 1px solid var(--rule-soft);
  padding-top: 18px;
}

.hero-ribbon {
  width: 100%;
  height: 160px;
  color: var(--accent);
  opacity: 0.32;
  margin-top: 32px;
  display: block;
}
.ribbon-path {
  animation: drawRibbon 2200ms var(--ease) 400ms forwards;
}
@keyframes drawRibbon { to { stroke-dashoffset: 0; } }

/* ─────────────────────── REFRAME ─────────────────────── */
.reframe {
  background: var(--paper-soft);
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
}
.reframe-inner {
  max-width: var(--col-xwide);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 80px;
  align-items: start;
}
.reframe-inner > .section-label { grid-column: 1 / -1; }
.reframe-h {
  font-size: clamp(36px, 5vw, 64px);
  line-height: 1.04;
  letter-spacing: -0.034em;
  margin-bottom: 28px;
  font-weight: 300;
  max-width: 18ch;
}
.reframe-h strong { display: inline; color: var(--accent-deep); }
.reframe-body { grid-column: 1; }
.reframe-body .lede {
  font-size: 22px;
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 38ch;
  margin: 0 0 28px 0;
}
.reframe-body p {
  font-size: 19px;
  line-height: 1.6;
  color: var(--ink-soft);
  max-width: 50ch;
}
.reframe-body p strong { color: var(--ink); }
.reframe-close {
  margin-top: 36px !important;
  padding-top: 28px;
  border-top: 1px solid var(--rule);
  font-size: 22px !important;
  line-height: 1.4 !important;
  color: var(--ink) !important;
  max-width: 38ch;
}
.reframe-close em { color: var(--accent-deep); font-style: italic; }

/* DATA LAYER aside — slides in from the right */
.datalayer-card {
  position: relative;
  grid-column: 2;
  background: var(--paper-card);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 26px 28px;
  margin-top: 60px;
  box-shadow: 0 1px 0 var(--rule-soft), 0 24px 48px -32px rgba(15,18,22,0.12);
}
.datalayer-card .dl-label {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--accent);
  margin: 0 0 14px 0;
}
.datalayer-card .dl-body {
  font-size: 17px;
  line-height: 1.55;
  color: var(--ink);
  margin: 0;
}
.datalayer-card .dl-body strong { color: var(--accent-deep); }
.dl-connector {
  position: absolute;
  left: -80px;
  top: 36px;
  width: 80px;
  height: 40px;
  color: var(--accent);
  opacity: 0.6;
}

/* ─────────────────────── DIAGNOSIS ─────────────────────── */
.diagnosis-inner { max-width: var(--col-wide); margin: 0 auto; }
.diagnosis-h {
  font-size: clamp(34px, 4.8vw, 58px);
  line-height: 1.06;
  letter-spacing: -0.032em;
  margin-bottom: 56px;
  max-width: 22ch;
  font-weight: 300;
}
.diagnosis-h strong { display: block; color: var(--accent-deep); }

.split-figure { margin: 0 0 56px 0; }
.split-svg { width: 100%; height: auto; max-width: 880px; display: block; }
.split-svg .dots circle { fill: var(--ink-soft); }
.split-svg .dots.split-up circle   { fill: var(--ink); }
.split-svg .dots.split-down circle { fill: var(--ink-faint); }

.split-trail { transition: stroke-dashoffset 1600ms var(--ease); }
.reveal.in .split-trail { stroke-dashoffset: 0; }
.trail-up   { transition-delay: 200ms; }
.trail-down { transition-delay: 350ms; }

.svg-label { font-family: var(--mono); font-size: 11px; letter-spacing: 0.06em; fill: var(--ink-mute); }
.svg-annot { font-family: var(--serif); font-style: italic; font-size: 14px; fill: var(--ink-soft); }
.split-figure figcaption {
  font-family: var(--sans);
  font-size: 14px;
  color: var(--ink-mute);
  margin-top: 14px;
  max-width: 540px;
}

.diagnosis-body p {
  font-size: 19px;
  line-height: 1.6;
  color: var(--ink-soft);
  max-width: 60ch;
  margin-bottom: 48px;
}

.pull {
  margin: 0;
  padding: 24px 0 24px 56px;
  border-left: 2px solid var(--accent);
  font-size: 28px;
  line-height: 1.32;
  color: var(--ink);
  max-width: 36ch;
  position: relative;
  font-weight: 300;
}
.pull strong { color: var(--accent-deep); }
.pull-mark {
  position: absolute;
  left: 18px;
  top: -4px;
  font-family: var(--serif);
  font-size: 72px;
  color: var(--accent);
  line-height: 1;
  font-style: italic;
}

/* ─────────────────────── ARC ─────────────────────── */
.arc { padding-top: 120px; padding-bottom: 120px; }
.arc-inner { max-width: var(--col-xwide); margin: 0 auto; }
.arc-h {
  font-size: clamp(40px, 5.4vw, 64px);
  line-height: 1.02;
  letter-spacing: -0.036em;
  margin-bottom: 32px;
  font-weight: 300;
  max-width: 16ch;
}
.arc-h strong { color: var(--accent-deep); }
.arc-intro {
  font-size: 20px;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 58ch;
  margin: 0 0 96px 0;
}

.stages { list-style: none; padding: 0; margin: 0; position: relative; }
.stage { display: grid; grid-template-columns: 80px 1fr; gap: 0; padding: 0 0 96px 0; position: relative; }
.stage:last-child { padding-bottom: 0; }

.stage-marker { position: relative; display: flex; flex-direction: column; align-items: center; padding-top: 8px; }
.stage-num {
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--accent);
  background: var(--paper);
  border: 1px solid var(--accent);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex; align-items: center; justify-content: center;
  z-index: 2;
  transition: background 320ms var(--ease), color 320ms var(--ease), transform 320ms var(--ease);
}
.stage.in .stage-num { background: var(--accent); color: var(--paper-card); transform: scale(1.04); }
.stage-rail { flex: 1; width: 1px; background: var(--rule); margin-top: 8px; margin-bottom: -96px; position: relative; }
.stage-rail::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 1px;
  height: 0;
  background: var(--accent);
  transition: height 900ms var(--ease);
}
.stage.in .stage-rail::before { height: 100%; }
.stage-rail-end { background: linear-gradient(to bottom, var(--rule), transparent); }

.stage-body { padding-left: 32px; }
.stage-head { display: flex; align-items: baseline; gap: 24px; margin-bottom: 28px; }
.stage-head h3 { font-size: clamp(30px, 3.4vw, 42px); letter-spacing: -0.012em; font-weight: 500; }
.stage-duration {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-mute);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin: 0;
}

.stage-cols { display: grid; grid-template-columns: 1.45fr 1fr; gap: 64px; align-items: start; }
.stage-prose p { font-size: 18px; line-height: 1.62; color: var(--ink-soft); }
.stage-prose p:not(:last-child) { margin-bottom: 18px; }
.stage-lede { color: var(--ink) !important; font-size: 20px !important; font-weight: 400; }

.stage-because {
  margin-top: 28px !important;
  padding: 16px 18px;
  border-left: 2px solid var(--accent);
  background: var(--paper-card);
  font-size: 16.5px !important;
  line-height: 1.5 !important;
  color: var(--ink) !important;
}
.because-label {
  font-family: var(--mono);
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--accent);
  display: inline;
  margin-right: 6px;
  font-weight: 500;
}

/* artifacts */
.artifact { position: sticky; top: 100px; }
.artifact-frame {
  background: var(--paper-card);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 22px;
  position: relative;
  aspect-ratio: 4 / 5;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  box-shadow: 0 1px 0 var(--rule-soft), 0 8px 24px -16px rgba(15,18,22,0.10);
  overflow: hidden;
}
.artifact-caption {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-mute);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-top: 16px;
  text-align: right;
}

/* artifact 1: doc */
.artifact-doc .doc-bar { height: 12px; width: 50%; background: var(--ink); margin-bottom: 18px; border-radius: 1px; }
.artifact-doc .doc-line { height: 7px; background: var(--paper-edge); border-radius: 1px; margin-bottom: 10px; }
.artifact-doc .doc-line.w90 { width: 90%; }
.artifact-doc .doc-line.w70 { width: 70%; }
.artifact-doc .doc-line.w80 { width: 80%; }
.artifact-doc .doc-line.w85 { width: 85%; }
.artifact-doc .doc-line.w60 { width: 60%; }
.artifact-doc .doc-block { height: 64px; background: var(--paper-edge); margin: 10px 0; border-radius: 2px; }
.artifact-doc .doc-stamp {
  position: absolute;
  bottom: 20px;
  right: 20px;
  font-family: var(--mono);
  font-size: 10px;
  line-height: 1.3;
  color: var(--accent);
  border: 1px solid var(--accent);
  padding: 6px 8px;
  border-radius: 2px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  transform: rotate(-3deg);
}

/* artifact 2: chat */
.artifact-chat { gap: 12px; display: flex; flex-direction: column; justify-content: center; }
.artifact-chat .chat-row { display: flex; justify-content: flex-end; }
.artifact-chat .chat-row-them { justify-content: flex-start; }
.artifact-chat .chat-bubble { border-radius: 12px; padding: 10px 14px; max-width: 75%; }
.artifact-chat .chat-me { background: var(--ink); width: 60%; height: 30px; }
.artifact-chat .chat-me-2 { width: 40%; }
.artifact-chat .chat-them {
  background: var(--paper-edge);
  width: 80%;
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px;
}
.artifact-chat .chat-line { height: 6px; background: var(--ink-faint); border-radius: 1px; }
.artifact-chat .chat-line.w70 { width: 70%; }
.artifact-chat .chat-line.w85 { width: 85%; }
.artifact-chat .chat-line.w55 { width: 55%; }
.artifact-chat .chat-meta {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-mute);
  text-align: center;
  margin-top: 16px;
  letter-spacing: 0.08em;
}
.artifact-chat .chat-meta em { color: var(--accent); font-style: italic; }

/* spectrum diagram */
.spectrum { margin: 24px 0 24px 0; max-width: 580px; }
.spectrum svg { width: 100%; height: auto; }
.spec-end { fill: var(--ink-faint); }
.spec-mid { fill: var(--accent); }
.spec-label { font-family: var(--mono); font-size: 11px; fill: var(--ink-mute); letter-spacing: 0.06em; }
.spec-mid-label { font-family: var(--serif); font-style: italic; font-size: 14px; fill: var(--accent-deep); }

/* artifact 3: workspace */
.artifact-workspace { padding: 0; flex-direction: row; }
.artifact-workspace .ws-sidebar {
  width: 28%; background: var(--paper-edge); padding: 18px 12px;
  display: flex; flex-direction: column; gap: 10px; border-right: 1px solid var(--rule);
}
.artifact-workspace .ws-tab { height: 8px; background: var(--ink-faint); border-radius: 1px; }
.artifact-workspace .ws-tab:nth-child(2) { background: var(--accent); }
.artifact-workspace .ws-main { flex: 1; padding: 20px; display: flex; flex-direction: column; gap: 12px; }
.artifact-workspace .ws-card {
  border: 1px solid var(--rule-soft);
  border-radius: 3px;
  padding: 10px;
  display: flex; flex-direction: column; gap: 6px;
}
.artifact-workspace .ws-card-active {
  border-color: var(--accent);
  background: color-mix(in oklab, var(--accent) 6%, transparent);
}
.artifact-workspace .ws-card-h { height: 8px; background: var(--ink); border-radius: 1px; width: 35%; }
.artifact-workspace .ws-card-l { height: 5px; background: var(--paper-edge); border-radius: 1px; }
.artifact-workspace .w50 { width: 50%; }
.artifact-workspace .w60 { width: 60%; }
.artifact-workspace .w70 { width: 70%; }
.artifact-workspace .w85 { width: 85%; }
.artifact-workspace .w90 { width: 90%; }

/* artifact 4: system */
.artifact-system { justify-content: center; align-items: center; }
.artifact-system svg { width: 80%; height: auto; max-width: 220px; }
.sys-block { fill: none; stroke: var(--ink-faint); stroke-width: 1.2; }
.sys-block.sys-accent { stroke: var(--accent); fill: color-mix(in oklab, var(--accent) 8%, transparent); }
.sys-link { stroke: var(--rule); stroke-width: 1; }
.sys-dot { fill: var(--ink-faint); }
.sys-dot.sys-dot-on { fill: var(--accent); }

/* ─────────────────────── IN PRACTICE / case study ─────────────────────── */
.practice {
  background: var(--paper-soft);
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
}
.practice-inner { max-width: var(--col-wide); margin: 0 auto; }
.practice-h {
  font-size: clamp(34px, 4.8vw, 56px);
  line-height: 1.04;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
  font-weight: 300;
  max-width: 18ch;
}
.practice-h strong { color: var(--accent-deep); }
.practice-intro {
  font-size: 18px;
  color: var(--ink-mute);
  font-style: italic;
  margin: 0 0 64px 0;
  max-width: 64ch;
  border-bottom: 1px solid var(--rule-soft);
  padding-bottom: 24px;
}
.practice-timeline { list-style: none; padding: 0; margin: 0 0 56px 0; }
.practice-step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 28px;
  padding: 0 0 40px 0;
  position: relative;
}
.practice-step:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 31px;
  top: 44px;
  bottom: 14px;
  width: 1px;
  background: var(--rule);
}
.ps-marker {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--paper-card);
  border: 1px solid var(--accent);
  width: 36px; height: 36px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 50%;
  margin-left: 14px;
  z-index: 2;
  position: relative;
}
.ps-body h4 {
  font-size: 20px;
  font-weight: 500;
  margin: 6px 0 10px 0;
  color: var(--ink);
}
.ps-body p {
  font-size: 17.5px;
  line-height: 1.62;
  color: var(--ink-soft);
  margin: 0;
  max-width: 60ch;
}
.ps-body p em { color: var(--accent-deep); font-style: italic; }
.practice-coda {
  font-size: 20px;
  line-height: 1.5;
  color: var(--ink);
  max-width: 50ch;
  font-style: italic;
  border-top: 1px solid var(--rule);
  padding-top: 28px;
}

/* ─────────────────────── KEEP ─────────────────────── */
.keep { }
.keep-inner { max-width: var(--col-xwide); margin: 0 auto; }
.keep-h {
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.12;
  letter-spacing: -0.024em;
  max-width: 24ch;
  margin-bottom: 56px;
  font-weight: 300;
}
.keep-h strong { color: var(--accent-deep); }
.keep-grid {
  list-style: none;
  padding: 0;
  margin: 0 0 48px 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
}
.keep-grid li {
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: transform 360ms var(--ease);
}
.keep-grid li:hover { transform: translateY(-3px); }
.keep-glyph { display: inline-flex; width: 36px; height: 36px; color: var(--accent); }
.keep-glyph svg { width: 100%; height: 100%; }
.keep-num {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-mute);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--rule);
}
.keep-grid p {
  font-size: 17px;
  line-height: 1.55;
  color: var(--ink);
  margin: 0;
}
.keep-coda {
  font-style: italic;
  color: var(--ink-mute);
  font-size: 16px;
  max-width: 60ch;
}

/* ─────────────────────── PRINCIPLE ─────────────────────── */
.principle { }
.principle-inner { max-width: var(--col-xwide); margin: 0 auto; }
.principle-h {
  font-size: clamp(34px, 4.6vw, 56px);
  line-height: 1.06;
  letter-spacing: -0.028em;
  margin-bottom: 56px;
  font-weight: 300;
  max-width: 20ch;
}
.principle-h strong { color: var(--accent-deep); }
.principle-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 36px 64px;
}
.principle-cell { border-top: 1px solid var(--rule); padding-top: 22px; }
.pc-k {
  font-size: 22px;
  line-height: 1.34;
  color: var(--ink);
  font-weight: 400;
  letter-spacing: -0.012em;
  margin: 0 0 12px 0;
}
.pc-v {
  font-size: 16.5px;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 48ch;
  margin: 0;
}

/* ─────────────────────── BEGIN ─────────────────────── */
.begin {
  background: var(--ink);
  color: var(--paper-card);
  padding-top: 120px;
  padding-bottom: 120px;
}
.begin-inner { max-width: var(--col-mid); margin: 0 auto; }
.begin .strap { color: var(--paper-edge); }
.begin-h {
  color: var(--paper-card);
  font-size: clamp(32px, 4.6vw, 56px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin-bottom: 28px;
  font-weight: 300;
}
.begin-h strong { color: var(--accent-soft); font-weight: 600; }
.begin-sub {
  font-size: 19px;
  line-height: 1.55;
  color: var(--paper-edge);
  max-width: 56ch;
  margin: 0 0 44px 0;
}
.begin-foot {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-faint);
  letter-spacing: 0.04em;
  margin: 40px 0 0 0;
}

.begin-actions {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
}
.cta-primary {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: var(--ink);
  color: var(--paper-card);
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.005em;
  padding: 14px 22px;
  border: 1px solid var(--ink);
  border-radius: 3px;
  text-decoration: none;
  transition: background 200ms var(--ease), border-color 200ms var(--ease), color 200ms var(--ease), transform 200ms var(--ease);
}
.cta-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper-card);
  transform: translateY(-1px);
}
.cta-primary .arr { transition: transform 200ms var(--ease); }
.cta-primary:hover .arr { transform: translateX(4px); }

.cta-secondary {
  font-family: var(--serif);
  font-style: italic;
  font-size: 16px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--rule);
}
.cta-secondary:hover { color: var(--accent-deep); border-bottom-color: var(--accent-deep); }

/* hero (light bg) variant of primary */
.hero .cta-primary { background: var(--ink); color: var(--paper-card); border-color: var(--ink); }
.hero .cta-primary:hover { background: var(--accent); border-color: var(--accent); }

/* begin (dark bg) variant */
.begin .cta-primary {
  background: var(--paper-card);
  color: var(--ink);
  border-color: var(--paper-card);
}
.begin .cta-primary:hover {
  background: var(--accent);
  color: var(--paper-card);
  border-color: var(--accent);
}
.begin .cta-secondary { color: var(--paper-edge); border-bottom-color: var(--ink-mute); }
.begin .cta-secondary:hover { color: var(--accent-soft); border-bottom-color: var(--accent-soft); }

/* ─────────────────────── FOOTER ─────────────────────── */
.site-foot {
  background: var(--paper);
  border-top: 1px solid var(--rule-soft);
  padding: 64px 56px 56px 56px;
}
.foot-inner { max-width: var(--col-xwide); margin: 0 auto; }
.foot-manifesto {
  font-size: 21px;
  line-height: 1.45;
  color: var(--ink);
  max-width: 50ch;
  margin: 0 0 56px 0;
  letter-spacing: -0.012em;
}
.foot-manifesto em { color: var(--accent-deep); font-style: italic; }
.foot-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  border-top: 1px solid var(--rule-soft);
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-mute);
}
.foot-wordmark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 500;
  color: var(--ink);
  border-bottom: none;
}
.foot-wordmark .wm-mark { width: 14px; height: 14px; }
.foot-nav { display: flex; gap: 24px; }
.foot-nav a { color: var(--ink-mute); border-bottom: none; }
.foot-nav a:hover { color: var(--accent-deep); }
.foot-meta { color: var(--ink-faint); }

/* ─────────────────────── responsive ─────────────────────── */
@media (max-width: 1080px) {
  .reframe-inner { grid-template-columns: 1fr; gap: 40px; }
  .datalayer-card { grid-column: 1; margin-top: 8px; }
  .dl-connector { display: none; }
}
@media (max-width: 980px) {
  section { padding: 80px 28px; }
  .hero { padding: 84px 28px 40px; }
  .head-inner { padding: 14px 28px; }
  .site-foot { padding: 56px 28px; }
  .stage { grid-template-columns: 56px 1fr; padding-bottom: 64px; }
  .stage-rail { margin-bottom: -64px; }
  .stage-cols { grid-template-columns: 1fr; gap: 32px; }
  .artifact { position: static; }
  .keep-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .principle-grid { grid-template-columns: 1fr; gap: 24px; }
  .practice-step { grid-template-columns: 48px 1fr; gap: 18px; }
  .practice-step::after { left: 23px !important; }
  .ps-marker { margin-left: 6px; width: 32px; height: 32px; font-size: 11px; }
}
@media (max-width: 640px) {
  body { font-size: 17px; }
  .keep-grid { grid-template-columns: 1fr; }
  .head-nav { gap: 14px; font-size: 13px; }
  .hero-actions, .begin-actions { gap: 20px; }
  .pull { padding-left: 32px; font-size: 22px; }
  .pull-mark { left: 6px; font-size: 56px; }
  .reframe-h, .arc-h, .diagnosis-h, .practice-h, .principle-h { font-size: clamp(28px, 7vw, 40px); }
}