/* atinformatics.com — "Signal"
 *
 * Docket CX (2026-10-01). Replaces the dark-gradient draft, which the founder
 * called tacky, simple and boring. He was right: it was the same indigo-to-
 * violet fade every AI-generated site ships.
 *
 * THE IDEA. Everything AT Informatics makes measures a signal and reports it
 * honestly — a vocal against a beat, a payroll row against a filed
 * declaration, a question against the article of law that answers it. So the
 * page is built like an instrument readout: editorial serif headlines,
 * monospace for anything that is a measurement, and diagrams drawn in SVG
 * rather than decoration dropped on top.
 *
 * ui-serif is doing the heavy lifting and it is deliberate. Every AI landing
 * page reaches for a geometric sans and a gradient. A system serif is free,
 * loads instantly, needs no third-party request, and looks like nothing a
 * model generates by default.
 *
 * NO JAVASCRIPT, NO EXTERNAL REQUESTS — which is what lets the shipped CSP be
 * default-src 'self' with script-src 'none'.
 */

:root {
  --paper:     #0b0b0c;
  --paper-2:   #111113;
  --raised:    #17171a;
  --rule:      #26262b;
  --rule-soft: #1c1c20;

  --ink:       #f2f0ec;
  --ink-2:     #a6a39c;
  --ink-3:     #6d6a64;

  --accent:    #ff8a3d;
  --accent-dim:#8a4a1f;
  --signal:    #4ad6a8;

  /* SF Pro on Apple devices, the closest native equivalent elsewhere. Zero
     external requests: a web font would be the only third-party fetch on the
     whole site and would break the strict CSP for the sake of one typeface. */
  --sans:  -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
           "Helvetica Neue", "Segoe UI", system-ui, sans-serif;
  --mono:  ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --gut: clamp(1.2rem, 5vw, 5rem);
  --measure: 36rem;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  letter-spacing: -.011em;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* a faint ruled grid, like paper for plotting on */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: -1; pointer-events: none;
  background-image:
    linear-gradient(var(--rule-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--rule-soft) 1px, transparent 1px);
  background-size: 96px 96px;
  -webkit-mask-image: radial-gradient(130vmax 90vmax at 70% -10%, #000 20%, transparent 72%);
          mask-image: radial-gradient(130vmax 90vmax at 70% -10%, #000 20%, transparent 72%);
  opacity: .5;
}

.wrap { width: 100%; max-width: 74rem; margin: 0 auto; padding: 0 var(--gut); }
.narrow { max-width: 46rem; }

a { color: inherit; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }

/* ------------------------------------------------------------ type */

/* Apple's display scale: the bigger it gets, the tighter it tracks. That one
   relationship is most of why their type reads expensive. */
h1, h2, h3 { margin: 0 0 .4em; font-family: var(--sans); }
h1 { font-size: clamp(2.8rem, 7.4vw, 5.6rem); line-height: 1.03; letter-spacing: -.045em; font-weight: 640; }
h2 { font-size: clamp(2rem, 4.2vw, 3.2rem);   line-height: 1.07; letter-spacing: -.035em; font-weight: 620; }
h3 { font-size: 1.24rem; line-height: 1.28; letter-spacing: -.021em; font-weight: 600; }
h1 em, h2 em { font-style: normal; color: var(--accent); }

p { margin: 0 0 1.1em; }
.lede { font-size: clamp(1.06rem, 1.9vw, 1.22rem); color: var(--ink-2); max-width: var(--measure); }
strong { font-weight: 600; color: var(--ink); }

.label {
  font-family: var(--mono); font-size: .7rem; letter-spacing: .18em;
  text-transform: uppercase; color: var(--ink-3);
}
.label .dot { color: var(--accent); }

code, pre { font-family: var(--mono); font-size: .86em; }
code { background: var(--raised); border: 1px solid var(--rule); padding: .12em .4em; border-radius: 4px; }
pre {
  background: var(--paper-2); border: 1px solid var(--rule); border-left: 2px solid var(--accent);
  padding: 1.1rem 1.25rem; overflow-x: auto; margin: 0 0 1.3em; line-height: 1.6;
}
pre code { background: none; border: 0; padding: 0; }

hr { border: 0; border-top: 1px solid var(--rule); margin: 3rem 0; }

/* ------------------------------------------------------------ header */

.site-head {
  position: sticky; top: 0; z-index: 40;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: saturate(150%) blur(12px);
  border-bottom: 1px solid var(--rule);
}
.site-head .wrap { display: flex; align-items: center; gap: 1.5rem; height: 60px; }
.brand { display: flex; align-items: center; gap: .6rem; text-decoration: none; font-family: var(--mono); font-size: .82rem; letter-spacing: .1em; text-transform: uppercase; }
.brand .mark { width: 9px; height: 9px; background: var(--accent); border-radius: 1px; }
.brand b { font-weight: 600; letter-spacing: .1em; }
.nav { margin-left: auto; display: flex; gap: 1.5rem; flex-wrap: wrap; }
.nav a { font-size: .88rem; color: var(--ink-3); text-decoration: none; transition: color .15s; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); }

/* ------------------------------------------------------------ hero */

.hero { padding: clamp(4.5rem, 13vw, 9rem) 0 clamp(2.5rem, 6vw, 4rem); position: relative; }
.hero .label { margin-bottom: 1.6rem; }
.hero h1 { max-width: 16ch; }
.hero .lede { margin-top: 1.6rem; }

.cta-row { display: flex; flex-wrap: wrap; gap: .9rem; margin-top: 2.4rem; align-items: center; }
.btn {
  display: inline-flex; align-items: center; gap: .55rem;
  font-family: var(--mono); font-size: .78rem; letter-spacing: .1em; text-transform: uppercase;
  padding: .95rem 1.5rem; text-decoration: none; border-radius: 2px;
  border: 1px solid var(--rule); transition: .18s;
}
.btn-primary { background: var(--accent); border-color: var(--accent); color: #140b04; font-weight: 600; }
.btn-primary:hover { background: #ffa15e; border-color: #ffa15e; }
.btn-ghost { color: var(--ink-2); }
.btn-ghost:hover { color: var(--ink); border-color: var(--ink-3); }
.btn-note { font-family: var(--mono); font-size: .74rem; color: var(--ink-3); margin-top: 1.4rem; }

/* ------------------------------------------------------------ sections */

section { padding: clamp(3.5rem, 8vw, 6.5rem) 0; position: relative; }
.rule-top { border-top: 1px solid var(--rule); }

.head-row { display: flex; align-items: baseline; gap: 1.5rem; margin-bottom: 2.6rem; flex-wrap: wrap; }
.head-row .label { white-space: nowrap; }

.grid { display: grid; gap: 1px; background: var(--rule); border: 1px solid var(--rule); }
@media (min-width: 740px) { .grid-2 { grid-template-columns: 1fr 1fr; } .grid-3 { grid-template-columns: repeat(3,1fr); } }

.cell { background: var(--paper); padding: 1.9rem 1.7rem; transition: background .2s; }
.cell:hover { background: var(--paper-2); }
.cell .label { margin-bottom: 1.1rem; }
.cell h3 { margin-bottom: .55rem; }
.cell p { color: var(--ink-2); font-size: .97rem; margin-bottom: 0; }
a.cell { text-decoration: none; display: flex; flex-direction: column; }
a.cell .go { margin-top: 1.3rem; font-family: var(--mono); font-size: .72rem; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
a.cell:hover .go { color: #ffa15e; }
.cell .status { margin-top: 1.2rem; align-self: flex-start; }

.status {
  display: inline-block; font-family: var(--mono); font-size: .64rem;
  letter-spacing: .14em; text-transform: uppercase; padding: .28em .6em;
  border: 1px solid var(--rule); color: var(--ink-3); border-radius: 2px;
}
.s-live  { color: #061410; background: var(--signal); border-color: var(--signal); font-weight: 700; }
.s-ready { color: var(--signal); border-color: color-mix(in srgb, var(--signal) 50%, var(--rule)); }
.s-beta  { color: var(--accent); border-color: var(--accent-dim); }
.s-pilot { color: var(--ink-2); }
.s-hold  { color: var(--ink-3); }

/* ------------------------------------------------------------ figures */

.fig { margin: 0; background: var(--paper-2); border: 1px solid var(--rule); padding: 1.6rem 1.7rem; }
.fig svg { display: block; width: 100%; height: auto; }
.fig figcaption { font-family: var(--mono); font-size: .72rem; color: var(--ink-3); margin-top: 1rem; letter-spacing: .04em; line-height: 1.7; }
.fig figcaption b { color: var(--ink-2); font-weight: 500; }

.readout { display: grid; gap: 1px; background: var(--rule); border: 1px solid var(--rule); }
@media (min-width: 680px) { .readout { grid-template-columns: repeat(3, 1fr); } }
.readout > div { background: var(--paper); padding: 1.7rem; }
.readout .v { font-family: var(--mono); font-size: clamp(2rem, 4.5vw, 3rem); line-height: 1; color: var(--accent); letter-spacing: -.02em; }
.readout .k { font-family: var(--mono); font-size: .74rem; color: var(--ink-3); margin-top: .9rem; letter-spacing: .03em; line-height: 1.5; }

.rows { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--rule); }
.rows li { padding: 1.3rem 0; border-bottom: 1px solid var(--rule); color: var(--ink-2); display: grid; gap: .35rem; }
@media (min-width: 740px) { .rows li { grid-template-columns: 15rem 1fr; gap: 2rem; align-items: start; } }
.rows b { color: var(--ink); font-weight: 600; font-size: 1.06rem; letter-spacing: -.018em; }

.note { border-left: 2px solid var(--accent); background: var(--paper-2); padding: 1.1rem 1.3rem; margin: 0 0 1.3em; }
.note p:last-child { margin-bottom: 0; }

.table-scroll { overflow-x: auto; margin: 0 0 1.4em; border: 1px solid var(--rule); }
table { border-collapse: collapse; width: 100%; font-size: .92rem; }
th, td { text-align: left; padding: .8rem 1rem; border-bottom: 1px solid var(--rule); vertical-align: top; }
th { font-family: var(--mono); font-size: .7rem; letter-spacing: .12em; text-transform: uppercase; color: var(--ink-3); white-space: nowrap; }
td { color: var(--ink-2); }
tr:last-child td { border-bottom: 0; }

/* ------------------------------------------------------------ motion */

@media (prefers-reduced-motion: no-preference) {
  @supports ((animation-timeline: view()) and (animation-range: entry)) {
    @keyframes rise { from { opacity: 0; transform: translateY(22px); } to { opacity: 1; transform: none; } }
    .reveal { animation: rise .8s cubic-bezier(.22,.8,.2,1) backwards; animation-timeline: view(); animation-range: entry 6% cover 28%; }
    @keyframes draw { from { stroke-dashoffset: var(--len, 1200); } to { stroke-dashoffset: 0; } }
    .trace { stroke-dasharray: var(--len, 1200); animation: draw 1.8s ease-out backwards; animation-timeline: view(); animation-range: entry 0% cover 45%; }
  }
}

/* ------------------------------------------------------------ documents */

.doc { padding: clamp(2.4rem, 6vw, 4rem) 0 5rem; }
.doc .wrap { max-width: 44rem; }
.doc h1 { font-size: clamp(2rem, 5vw, 3rem); }
.doc h2 { font-size: clamp(1.2rem, 2.4vw, 1.5rem); margin-top: 2.8em; }
.doc h3 { font-size: 1.04rem; margin-top: 2em; font-weight: 640; }
.doc p, .doc li { color: var(--ink-2); }
.doc ul, .doc ol { padding-left: 1.2em; margin: 0 0 1.2em; }
.doc li { margin: .4em 0; }
.doc-meta { font-family: var(--mono); font-size: .74rem; color: var(--ink-3); border-bottom: 1px solid var(--rule); padding-bottom: 1.4rem; margin-bottom: 2.4rem; }
.doc-nav { display: flex; flex-wrap: wrap; gap: 1.3rem; margin: 0 0 2.6rem; padding-bottom: 1.3rem; border-bottom: 1px solid var(--rule); }
.doc-nav a { font-family: var(--mono); font-size: .74rem; letter-spacing: .1em; text-transform: uppercase; text-decoration: none; color: var(--ink-3); }
.doc-nav a:hover { color: var(--ink); }
.doc-nav a[aria-current="page"] { color: var(--accent); }

/* ------------------------------------------------------------ footer */

.site-foot { border-top: 1px solid var(--rule); padding: 3.5rem 0 4rem; margin-top: 4rem; }
.site-foot .cols { display: grid; gap: 2.4rem; }
@media (min-width: 740px) { .site-foot .cols { grid-template-columns: 2fr 1fr 1fr 1fr; } }
.site-foot h4 { font-family: var(--mono); font-size: .68rem; letter-spacing: .16em; text-transform: uppercase; color: var(--ink-3); margin: 0 0 1rem; font-weight: 500; }
.site-foot ul { list-style: none; padding: 0; margin: 0; }
.site-foot li { margin: .45em 0; }
.site-foot a { color: var(--ink-2); text-decoration: none; font-size: .92rem; }
.site-foot a:hover { color: var(--ink); }
.site-foot .about { color: var(--ink-3); font-size: .92rem; max-width: 24rem; margin-top: 1rem; }
.legal-line { margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--rule); font-family: var(--mono); font-size: .7rem; color: var(--ink-3); line-height: 1.9; letter-spacing: .02em; }

.skip { position: absolute; left: -9999px; background: var(--accent); color: #140b04; padding: .7rem 1.1rem; z-index: 60; }
.skip:focus { left: 0; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}