/* ─────────────────────────────────────────────────────────────
   TEND · v2 stylesheet
   Cool linen paper, near-black ink, one accent (fountain-pen ink-blue).
   ───────────────────────────────────────────────────────────── */

: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 (the one color) */
  --accent:       #1F4D6B;
  --accent-deep:  #143548;
  --accent-soft:  #5887A8;

  /* diagram-only secondary */
  --moss:    #4A6358;
  --moss-d:  #36493F;

  /* rules and softer dividers */
  --rule:       #C9C5BB;
  --rule-soft:  #DDD9D1;

  /* type · all Plex, single family, single voice */
  --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:    760px;
  --col-wide:   1100px;
  --col-xwide:  1280px;
}

/* ─────────────────────── base ─────────────────────── */
* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
}
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;
}
::selection { background: var(--accent); color: var(--paper-card); }

h1, h2, h3 {
  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 120ms ease, color 120ms ease;
}
a:hover { border-bottom-color: var(--accent); color: var(--accent-deep); }

em { font-style: italic; }

/* strong: argument turns. Load-bearing emphasis. */
strong {
  font-weight: 600;
  letter-spacing: -0.012em;
  color: var(--ink);
}
/* b: inline highlight, semantic accent without shouting. */
b {
  font-weight: 500;
  color: var(--ink);
}

/* ─────────────────────── 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);
  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;
  font-weight: 400;
  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 180ms ease;
}
.head-nav a:hover { color: var(--ink); }
.head-nav a:hover::after { right: 0; }

/* ─────────────────────── section scaffolding ─────────────────────── */
section { padding: 130px 56px; }
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;
}
.eyebrow {
  font-family: var(--sans);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
  margin: 0 0 28px 0;
  font-weight: 500;
}
.h2-emph {
  color: var(--accent-deep);
  font-weight: 600;
  font-style: normal;
  letter-spacing: -0.034em;
}

/* ─────────────────────── BEAT 1 · HOOK ─────────────────────── */
.hook { padding: 168px 56px 132px; }
.hook-inner { max-width: var(--col-mid); margin: 0 auto; }
.hero {
  font-size: clamp(52px, 7.6vw, 104px);
  line-height: 1.02;
  letter-spacing: -0.04em;
  font-weight: 300;
  margin: 0 0 44px 0;
}
.hero strong {
  font-weight: 600;
  letter-spacing: -0.046em;
  color: var(--accent-deep);
}
.hero-emph {
  font-style: italic;
  color: var(--accent);
  font-weight: 300;
}
.hero-sub {
  font-size: 22px;
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 42ch;
  margin: 0 0 36px 0;
  letter-spacing: -0.008em;
}
.hero-sub b { color: var(--ink); font-weight: 500; }
.hero-sub em {
  color: var(--accent-deep);
  font-style: italic;
  display: inline-block;
  margin-top: 4px;
}
.hero-meta {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-mute);
  margin: 0;
  text-transform: none;
}
.hook-rule {
  margin-top: 96px;
  color: var(--rule);
  max-width: 220px;
  height: 8px;
}
.hook-rule svg { width: 100%; height: 100%; }

/* ─────────────────────── BEAT 2 · REFRAME ─────────────────────── */
.reframe {
  background: var(--paper-soft);
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
  padding-top: 130px;
  padding-bottom: 130px;
}
.reframe-inner { max-width: var(--col-mid); margin: 0 auto; }
.reframe h2 {
  font-size: clamp(34px, 4.6vw, 56px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin-bottom: 28px;
}
.lede {
  font-size: 21px;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 40ch;
  margin: 0 0 40px 0;
}

/* the small solved/unsolved figure */
.solved-figure {
  margin: 8px 0 44px 0;
  padding: 0;
}
.solved-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  max-width: 520px;
}
.solved-cell {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px 18px;
  background: var(--paper-card);
  border: 1px solid var(--rule-soft);
  border-radius: 4px;
}
.solved-cap {
  font-family: var(--mono);
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--ink-mute);
}
.solved-bar { width: 100%; height: 40px; display: block; }
.bar-fill   { fill: var(--ink); }
.bar-track  { fill: var(--paper-edge); }
.bar-fill-soft { fill: var(--accent-soft); opacity: 0.7; }
.bar-tag    {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  fill: var(--paper-card);
}
.solved-no .bar-tag { fill: var(--ink-mute); }

.reframe-body p { font-size: 20px; max-width: 56ch; }
.reframe-body p strong { color: var(--ink); }
.reframe-close {
  margin-top: 64px !important;
  padding-top: 36px;
  border-top: 1px solid var(--rule);
  font-size: 26px !important;
  color: var(--ink) !important;
  line-height: 1.34 !important;
  font-weight: 400;
  max-width: 36ch;
}
.reframe-close-emph {
  color: var(--accent-deep);
  font-weight: 600;
  display: inline-block;
  letter-spacing: -0.015em;
}

/* ─────────────────────── BEAT 3 · DIAGNOSIS ─────────────────────── */
.diagnosis { padding-top: 110px; padding-bottom: 110px; }
.diagnosis-inner { max-width: var(--col-wide); margin: 0 auto; }
.diagnosis h2 {
  font-size: clamp(34px, 4.6vw, 54px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin-bottom: 56px;
}

.split-figure {
  margin: 0 0 56px 0;
  padding: 0;
}
.split-svg {
  width: 100%;
  height: auto;
  max-width: 820px;
  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); }
.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: 13px;
  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 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  margin-bottom: 64px;
}
.diagnosis-body p {
  font-size: 18px;
  line-height: 1.6;
  color: var(--ink-soft);
}

.pull {
  position: relative;
  margin: 0 0 56px 0;
  padding: 24px 0 24px 56px;
  border-left: 2px solid var(--accent);
  font-size: 28px;
  line-height: 1.32;
  font-weight: 400;
  color: var(--ink);
  max-width: 36ch;
}
.pull-mark {
  position: absolute;
  left: 18px;
  top: -4px;
  font-family: var(--serif);
  font-size: 72px;
  color: var(--accent);
  line-height: 1;
  font-style: italic;
}

.diagnosis-close {
  font-size: 22px;
  line-height: 1.4;
  color: var(--ink);
  max-width: 44ch;
  font-style: italic;
}

/* ─────────────────────── BEAT 4 · ARC ─────────────────────── */
.arc {
  background: var(--paper);
  padding-top: 120px;
  padding-bottom: 120px;
}
.arc-inner { max-width: var(--col-xwide); margin: 0 auto; }
.arc h2 {
  font-size: clamp(38px, 5vw, 60px);
  line-height: 1.04;
  letter-spacing: -0.032em;
  margin-bottom: 32px;
}
.arc-intro {
  font-size: 20px;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 56ch;
  margin: 0 0 80px 0;
}

.stages {
  list-style: none;
  padding: 0;
  margin: 0;
  position: relative;
}

.stage {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 0;
  padding: 0 0 80px 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;
}
.stage-rail {
  flex: 1;
  width: 1px;
  background: var(--rule);
  margin-top: 8px;
  margin-bottom: -80px;
}
.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-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 (specimens on the right side of each stage) ─────── */
.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);
}
.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: readiness 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 inside stage 3 prose */
.spectrum {
  margin: 32px 0 32px 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); }

/* ─────────────────────── BEAT 5 · KEEP ─────────────────────── */
.keep {
  background: var(--paper-soft);
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
}
.keep-inner { max-width: var(--col-xwide); margin: 0 auto; }
.keep h2 {
  font-size: clamp(28px, 3.6vw, 42px);
  line-height: 1.18;
  letter-spacing: -0.022em;
  max-width: 26ch;
  margin-bottom: 56px;
}
.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;
}
.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;
}

/* ─────────────────────── BEAT 6 · PRINCIPAL / HOW WE WORK ─────────────────────── */
.principal { padding-top: 110px; padding-bottom: 110px; }
.principal-inner { max-width: var(--col-xwide); margin: 0 auto; }
.principal-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 80px;
  align-items: start;
}
.principal-name {
  font-size: clamp(32px, 4.2vw, 52px);
  line-height: 1.08;
  letter-spacing: -0.018em;
  margin-bottom: 28px;
  max-width: 18ch;
}
.principal-body p {
  font-size: 19px;
  line-height: 1.6;
  color: var(--ink-soft);
  max-width: 58ch;
}

.principal-side { padding-top: 10px; }
.side-card {
  background: var(--paper-card);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 24px 26px;
}
.side-label {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--ink-mute);
  margin: 0 0 16px 0;
}
.side-list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.side-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid var(--rule-soft);
  font-size: 15px;
  line-height: 1.4;
}
.side-list li:last-child { border-bottom: none; }
.side-k {
  font-family: var(--sans);
  color: var(--ink-mute);
  font-size: 13px;
}
.side-v {
  font-family: var(--serif);
  font-style: italic;
  color: var(--ink);
  font-size: 15px;
  text-align: right;
}

/* ─────────────────────── CTA / START ─────────────────────── */
.start {
  background: var(--ink);
  color: var(--paper-card);
  padding-top: 120px;
  padding-bottom: 120px;
}
.start-inner { max-width: var(--col-mid); margin: 0 auto; }
.start .eyebrow { color: var(--paper-edge); }
.start-h {
  color: var(--paper-card);
  font-size: clamp(32px, 4.4vw, 50px);
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 48px;
  font-weight: 400;
}
.start-h .h2-emph {
  color: var(--accent-soft);
  font-weight: 600;
}
.start-meta {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-faint);
  margin: -24px 0 40px 0;
}
.start-actions {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
}
.cta-primary {
  display: inline-block;
  background: var(--paper-card);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.005em;
  padding: 14px 22px;
  border: 1px solid var(--paper-card);
  border-radius: 3px;
  text-decoration: none;
}
.cta-primary:hover {
  background: var(--accent);
  color: var(--paper-card);
  border-color: var(--accent);
}
.cta-secondary {
  font-family: var(--serif);
  font-style: italic;
  font-size: 16px;
  color: var(--paper-edge);
  border-bottom: 1px solid var(--ink-mute);
}
.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;
  font-weight: 400;
  color: var(--ink);
  max-width: 48ch;
  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 {
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.012em;
}
.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: 980px) {
  section { padding: 80px 32px; }
  .head-inner { padding: 14px 32px; }
  .site-foot { padding: 56px 32px; }
  .diagnosis-body { grid-template-columns: 1fr; gap: 24px; }
  .stage { grid-template-columns: 56px 1fr; }
  .stage-cols { grid-template-columns: 1fr; gap: 40px; }
  .keep-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .principal-grid { grid-template-columns: 1fr; gap: 40px; }
  .solved-pair { max-width: 100%; }
  .artifact { position: static; }
}
@media (max-width: 640px) {
  body { font-size: 18px; }
  .keep-grid { grid-template-columns: 1fr; }
  .head-nav { gap: 18px; }
}