/* ============================================================
   indigo-matter Field Notes — Aizome direction
   Kindred to domio-smart-home.app: indigo dye + warm paper,
   editorial serif display, letterpress detailing. These pages
   are the engineering gazette of that same world.
   ============================================================ */

:root {
  color-scheme: light;

  --paper:       #F2EDE2;
  --paper-deep:  #EAE3D2;
  --ink:         #15184A;
  --ink-soft:    #3D406B;
  --ink-faint:   #5A5C88;
  --rule:        rgba(21, 24, 74, 0.13);
  --rule-strong: rgba(21, 24, 74, 0.22);

  --leaf:   #3B5A3E;
  --ochre:  #B07A2B;
  --purple: #9932CC;

  --accent: var(--leaf);            /* page-level override */
  --accent-soft: rgba(59, 90, 62, 0.10);

  --code-bg: rgba(21, 24, 74, 0.06);

  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 22px;
  --r-pill: 999px;

  --display: "Fraunces", ui-serif, Georgia, "Times New Roman", serif;
  --body: "General Sans", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, monospace;

  --ease-out: cubic-bezier(.2, .8, .2, 1);
  --ease-out-soft: cubic-bezier(.25, 1, .5, 1);

  --measure: 68ch;
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  font-size: 1.0625rem;
  line-height: 1.7;
  font-weight: 400;
  /* faint indigo-dye wash pooling at the page edges */
  background-image:
    radial-gradient(1100px 500px at 85% -8%, rgba(21, 24, 74, 0.05), transparent 65%),
    radial-gradient(900px 600px at -10% 110%, rgba(21, 24, 74, 0.045), transparent 60%);
  background-attachment: fixed;
}

/* paper grain */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 2;
  opacity: .35;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3CfeComponentTransfer%3E%3CfeFuncA type='linear' slope='0.05'/%3E%3C/feComponentTransfer%3E%3C/filter%3E%3Crect width='180' height='180' filter='url(%23n)'/%3E%3C/svg%3E");
}

::selection { background: var(--ink); color: var(--paper); }

a { color: var(--ink); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; transition: color .18s var(--ease-out); }
a:hover { color: var(--accent); }

code, pre {
  font-family: var(--mono);
  font-size: .86em;
}
code { background: var(--code-bg); padding: .12em .38em; border-radius: 5px; }
pre {
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: var(--r-md);
  padding: 1.1rem 1.3rem;
  overflow-x: auto;
  line-height: 1.55;
}
pre code { background: none; padding: 0; }

/* ---------- Masthead ---------- */

.mast {
  max-width: 1060px;
  margin: 0 auto;
  padding: clamp(2.2rem, 6vw, 4.5rem) clamp(1.2rem, 4vw, 2.5rem) 0;
}

.mast-rule {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  border-top: 3px double var(--rule-strong);
  border-bottom: 1px solid var(--rule);
  padding: .55rem .1rem .6rem;
  font-size: .78rem;
  font-weight: 500;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.mast-rule a { text-decoration: none; color: var(--ink-faint); }
.mast-rule a:hover { color: var(--accent); }
.mast-rule .no { color: var(--accent); font-weight: 600; }

h1 {
  font-family: var(--display);
  font-optical-sizing: auto;
  font-size: clamp(2.6rem, 7vw, 4.6rem);
  font-weight: 560;
  line-height: 1.04;
  letter-spacing: -0.015em;
  margin: 2.4rem 0 0;
  max-width: 18ch;
  text-wrap: balance;
}
h1 em { font-style: italic; font-weight: 480; color: var(--accent); }

.standfirst {
  font-family: var(--display);
  font-size: clamp(1.12rem, 2.3vw, 1.38rem);
  font-weight: 430;
  font-style: italic;
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 52ch;
  margin: 1.4rem 0 0;
}

.mast-foot {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 1.6rem;
  align-items: center;
  margin: 2.2rem 0 0;
  padding-bottom: 1.4rem;
  border-bottom: 1px solid var(--rule);
  font-size: .82rem;
  letter-spacing: .05em;
  color: var(--ink-faint);
}

/* ---------- Article scaffold ---------- */

main {
  max-width: 1060px;
  margin: 0 auto;
  padding: 0 clamp(1.2rem, 4vw, 2.5rem) 4rem;
}

section.note {
  display: grid;
  grid-template-columns: minmax(0, 110px) minmax(0, 1fr);
  gap: 0 clamp(1.2rem, 3.5vw, 3rem);
  padding: clamp(2rem, 5vw, 3.2rem) 0 0;
  border-bottom: 1px solid var(--rule);
  margin-bottom: clamp(1rem, 3vw, 1.8rem);
}
section.note:last-of-type { border-bottom: none; }

.sec-no {
  font-family: var(--display);
  font-weight: 600;
  font-size: 1rem;
  color: var(--accent);
  letter-spacing: .08em;
  padding-top: .55rem;
}
.sec-no::after {
  content: "";
  display: block;
  width: 2.2rem;
  height: 2px;
  margin-top: .55rem;
  background: var(--accent);
}

.sec-body { max-width: var(--measure); padding-bottom: 1.6rem; }

h2 {
  font-family: var(--display);
  font-size: clamp(1.7rem, 3.6vw, 2.3rem);
  font-weight: 560;
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 0 0 1.1rem;
  text-wrap: balance;
}

h3 {
  font-family: var(--display);
  font-size: 1.22rem;
  font-weight: 600;
  margin: 2rem 0 .6rem;
}

p { margin: 0 0 1.1rem; }
ul, ol { margin: 0 0 1.2rem; padding-left: 1.3rem; }
li { margin-bottom: .45rem; }
li::marker { color: var(--accent); font-weight: 600; }
strong { font-weight: 600; }

/* opening drop cap */
.dropcap::first-letter {
  font-family: var(--display);
  font-weight: 600;
  font-size: 3.4em;
  float: left;
  line-height: .82;
  padding: .06em .12em 0 0;
  color: var(--accent);
}

/* ---------- Editorial furniture ---------- */

.pull {
  font-family: var(--display);
  font-style: italic;
  font-weight: 460;
  font-size: clamp(1.25rem, 2.6vw, 1.55rem);
  line-height: 1.42;
  color: var(--ink);
  border-left: 3px solid var(--accent);
  padding: .35rem 0 .35rem 1.3rem;
  margin: 1.8rem 0;
  max-width: 46ch;
  text-wrap: balance;
}
.pull small {
  display: block;
  font-family: var(--body);
  font-style: normal;
  font-size: .76rem;
  font-weight: 500;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-top: .6rem;
}

.aside {
  background: var(--paper-deep);
  border: 1px solid var(--rule);
  border-radius: var(--r-md);
  padding: 1.1rem 1.3rem;
  margin: 1.5rem 0;
  font-size: .97rem;
}
.aside .tag {
  display: inline-block;
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: .4rem;
}
.aside.caution { border-color: rgba(176, 122, 43, .5); }
.aside.caution .tag { color: var(--ochre); }

/* rubber stamp */
.stamp {
  display: inline-block;
  font-weight: 600;
  font-size: .78rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--accent);
  border: 2px solid var(--accent);
  border-radius: var(--r-sm);
  padding: .3rem .7rem;
  transform: rotate(-2deg);
  -webkit-mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='40'%3E%3Cfilter id='r'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.6' numOctaves='2'/%3E%3CfeComponentTransfer%3E%3CfeFuncA type='discrete' tableValues='0 .4 .7 1 1 1 1 1 1 1'/%3E%3C/feComponentTransfer%3E%3C/filter%3E%3Crect width='120' height='40' filter='url(%23r)'/%3E%3C/svg%3E");
  mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='40'%3E%3Cfilter id='r'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.6' numOctaves='2'/%3E%3CfeComponentTransfer%3E%3CfeFuncA type='discrete' tableValues='0 .4 .7 1 1 1 1 1 1 1'/%3E%3C/feComponentTransfer%3E%3C/filter%3E%3Crect width='120' height='40' filter='url(%23r)'/%3E%3C/svg%3E");
}
.stamp.ochre { color: var(--ochre); border-color: var(--ochre); transform: rotate(1.5deg); }

/* chips */
.chips { display: flex; flex-wrap: wrap; gap: .55rem; margin: 1rem 0 1.4rem; padding: 0; list-style: none; }
.chips li {
  margin: 0;
  border: 1px solid var(--rule-strong);
  border-radius: var(--r-pill);
  padding: .32rem .85rem;
  font-size: .85rem;
  font-weight: 500;
  background: rgba(255,255,255,.35);
}
.chips li b { color: var(--accent); font-weight: 600; }

/* specimen tables */
.specimen { width: 100%; border-collapse: collapse; margin: 1.4rem 0; font-size: .95rem; }
.specimen caption {
  caption-side: top;
  text-align: left;
  font-size: .74rem;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding-bottom: .55rem;
}
.specimen th, .specimen td {
  text-align: left;
  vertical-align: top;
  padding: .6rem .8rem .6rem 0;
  border-bottom: 1px solid var(--rule);
}
.specimen thead th {
  font-size: .76rem;
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  border-bottom: 2px solid var(--rule-strong);
}
.specimen td:first-child, .specimen th:first-child { padding-left: 0; }
.specimen tbody th { font-weight: 600; }

/* numbered letterpress steps */
.steps { counter-reset: step; list-style: none; padding: 0; margin: 1.4rem 0; }
.steps > li {
  counter-increment: step;
  position: relative;
  padding: 0 0 1.3rem 3.4rem;
  margin: 0;
}
.steps > li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: .05em;
  font-family: var(--display);
  font-weight: 600;
  font-size: 1.5rem;
  color: var(--accent);
}
.steps > li::after {
  content: "";
  position: absolute;
  left: .55rem;
  top: 2.3rem;
  bottom: .4rem;
  width: 1px;
  background: var(--rule);
}
.steps > li:last-child::after { display: none; }
.steps b:first-child { font-weight: 600; }

/* ---------- Flow diagram ---------- */

.flow {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin: 1.8rem 0;
  max-width: 34rem;
}
.flow-node {
  border: 1.5px solid var(--rule-strong);
  border-radius: var(--r-md);
  background: rgba(255,255,255,.45);
  padding: .85rem 1.1rem;
  box-shadow: 0 1px 0 rgba(21,24,74,.06);
}
.flow-node b { font-weight: 600; display: block; }
.flow-node span { font-size: .86rem; color: var(--ink-soft); }
.flow-node.hero { border-color: var(--accent); background: var(--accent-soft); }
.flow-link {
  display: flex;
  align-items: center;
  gap: .7rem;
  padding: .45rem 0 .45rem 1.4rem;
  color: var(--ink-faint);
  font-size: .8rem;
  letter-spacing: .06em;
}
.flow-link::before {
  content: "";
  width: 1px;
  align-self: stretch;
  background: var(--rule-strong);
  margin-right: .2rem;
}
.flow-link i { font-style: normal; font-family: var(--mono); font-size: .78rem; color: var(--accent); }

/* ---------- Strata (testing layers) ---------- */

.strata { list-style: none; margin: 2rem 0; padding: 0; }
.strata li {
  display: grid;
  grid-template-columns: 3.2rem 1fr;
  gap: 1.1rem;
  align-items: start;
  border: 1.5px solid var(--rule-strong);
  border-radius: var(--r-md);
  padding: 1rem 1.2rem;
  margin: 0 0 .6rem;
  background: rgba(255,255,255,.4);
}
.strata li:nth-child(1) { margin-right: 18%; }
.strata li:nth-child(2) { margin-right: 12%; margin-left: 2%; }
.strata li:nth-child(3) { margin-right: 6%;  margin-left: 4%; }
.strata li:nth-child(4) { margin-left: 6%; border-color: var(--accent); background: var(--accent-soft); }
.strata .layer-no {
  font-family: var(--display);
  font-weight: 600;
  font-size: 1.7rem;
  color: var(--accent);
  line-height: 1;
}
.strata b { font-weight: 600; }
.strata p { margin: .15rem 0 0; font-size: .92rem; color: var(--ink-soft); }

/* ---------- Reveal motion ----------
   Progressive enhancement: hidden state applies only once the inline
   head script has stamped html.js — no-JS readers, print, and full-page
   screenshot tools always get visible content. */

html.js .reveal { opacity: 0; transform: translateY(14px); transition: opacity .7s var(--ease-out-soft), transform .7s var(--ease-out-soft); }
html.js .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  html.js .reveal { opacity: 1; transform: none; transition: none; }
}
@media print {
  html.js .reveal { opacity: 1; transform: none; }
  body::before { display: none; }
}

/* ---------- Footer ---------- */

footer.colophon {
  max-width: 1060px;
  margin: 0 auto;
  padding: 2rem clamp(1.2rem, 4vw, 2.5rem) 3.5rem;
  border-top: 3px double var(--rule-strong);
  font-size: .9rem;
  color: var(--ink-soft);
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2.4rem;
  justify-content: space-between;
  align-items: baseline;
}
footer.colophon .dot { color: var(--purple); }

/* ---------- Small screens ---------- */

@media (max-width: 700px) {
  section.note { grid-template-columns: 1fr; }
  .sec-no { padding-top: 0; }
  .strata li, .strata li:nth-child(n) { margin-left: 0; margin-right: 0; }
}