/*
 * The interim front page (ADR 0034). Every colour, size and family comes from tokens.css
 * (docs/DESIGN.md section 3); tests/site/test_interim_page.py fails on a raw colour, a px font
 * size or a font-family that is not a token. Replaced by apps/site (track 2).
 */

@font-face {
  font-family: "IBM Plex Sans";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("fonts/IBMPlexSans-Regular-Latin1.woff2") format("woff2");
}

@font-face {
  font-family: "IBM Plex Sans";
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url("fonts/IBMPlexSans-SemiBold-Latin1.woff2") format("woff2");
}

@font-face {
  font-family: "IBM Plex Mono";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("fonts/IBMPlexMono-Regular-Latin1.woff2") format("woff2");
}

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

html {
  font-size: 100%;
  scroll-padding-top: calc(var(--s-9) + var(--s-5));
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--t-md);
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3 {
  margin: 0;
  font-weight: 600;
  text-wrap: balance;
}

h2 {
  font-size: var(--t-2xl);
  line-height: 1.2;
  margin-bottom: var(--s-6);
}

h3 {
  font-size: var(--t-lg);
  line-height: 1.4;
  margin-bottom: var(--s-3);
}

p {
  margin: 0 0 var(--s-5);
  max-width: 68ch;
}

a {
  color: var(--accent);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 1px;
}

a:hover {
  text-decoration-thickness: 2px;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--r-sm);
}

code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  overflow-wrap: anywhere;
}

.wrap {
  width: 100%;
  max-width: 72rem;
  margin-inline: auto;
  padding-inline: clamp(var(--s-5), 4vw, var(--s-7));
}

/* Skip link: off screen until focused (DESIGN 9) */
.skip {
  position: absolute;
  left: var(--s-5);
  top: calc(-1 * var(--s-9));
  z-index: 10;
  padding: var(--s-3) var(--s-4);
  background: var(--accent);
  color: var(--accent-ink);
  border-radius: var(--r-sm);
}

.skip:focus {
  top: var(--s-3);
}

/* Navigation bar: the one translucent surface, over content only (DESIGN 2, "Glass") */
.bar {
  position: sticky;
  top: 0;
  z-index: 5;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

@supports (backdrop-filter: blur(12px)) or (-webkit-backdrop-filter: blur(12px)) {
  .bar {
    background: color-mix(in srgb, var(--surface) 72%, transparent);
    -webkit-backdrop-filter: blur(12px) saturate(1.2);
    backdrop-filter: blur(12px) saturate(1.2);
  }
}

@media (prefers-reduced-transparency: reduce) {
  .bar {
    background: var(--surface);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }
}

.bar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-5);
  min-height: var(--s-9);
}

.wordmark {
  color: var(--ink);
  font-weight: 600;
  font-size: var(--t-lg);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: var(--s-6);
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: var(--t-sm);
}

.nav-links a {
  color: var(--ink-2);
  text-decoration: none;
}

.nav-links a:hover {
  color: var(--ink);
}

@media (max-width: 52rem) {
  .nav-optional {
    display: none;
  }
}

/* Hero: the sentence, the status, and how it will work beside it (DESIGN 6, D189) */
.hero {
  display: grid;
  gap: var(--s-8);
  padding-block: var(--s-9);
}

@media (min-width: 64rem) {
  .hero {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    align-items: start;
    padding-block: var(--s-9) calc(var(--s-9) + var(--s-6));
  }
}

h1 {
  font-size: clamp(var(--t-2xl), 1.4rem + 2.6vw, var(--t-3xl));
  line-height: 1.1;
  margin-bottom: var(--s-6);
}

.lead {
  font-size: var(--t-lg);
  color: var(--ink-2);
}

.status {
  color: var(--ink-2);
  border-left: 2px solid var(--line-strong);
  padding-left: var(--s-4);
}

.status-label {
  color: var(--ink);
  font-weight: 600;
}

/* How it will work: five steps as an ordered list on a hairline rail; it reads, prints and wraps as a
   list. No example values (D189). */
.steps {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: var(--s-6);
}

.steps-title {
  font-size: var(--t-lg);
  line-height: 1.4;
  margin-bottom: var(--s-6);
  padding-bottom: var(--s-5);
  border-bottom: 1px solid var(--line);
}

.chain {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.chain li {
  position: relative;
  display: grid;
  gap: var(--s-1);
  padding: 0 0 var(--s-5) var(--s-7);
  counter-increment: step;
  font-size: var(--t-sm);
  line-height: 1.45;
}

.chain li:last-child {
  padding-bottom: 0;
}

/* The rail between nodes */
.chain li::after {
  content: "";
  position: absolute;
  left: calc(var(--s-3) - 0.5px);
  top: var(--s-6);
  bottom: 0;
  border-left: 1px solid var(--line-strong);
}

.chain li:last-child::after {
  display: none;
}

/* The node: the step number in a square, so order never depends on the line alone */
.chain li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: var(--s-5);
  height: var(--s-5);
  display: grid;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-sm);
  background: var(--surface);
  color: var(--ink-2);
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.chain .step {
  font-weight: 600;
  font-size: var(--t-md);
  color: var(--ink);
}

.chain .detail {
  color: var(--ink-2);
}

/* Sections: flat, separated by hairlines, generous space (DESIGN 3.3: site uses 24/32/48) */
.band {
  border-top: 1px solid var(--line);
  padding-block: var(--s-9);
}

.cols-3,
.cols-2 {
  display: grid;
  gap: var(--s-8);
}

@media (min-width: 56rem) {
  .cols-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--s-7);
  }

  .cols-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.cols-3 p {
  color: var(--ink-2);
}

.intro {
  color: var(--ink-2);
}

.points {
  margin: 0 0 var(--s-6);
  padding-left: var(--s-5);
  max-width: 68ch;
}

.points li {
  margin-bottom: var(--s-3);
  padding-left: var(--s-2);
}

.points li::marker {
  color: var(--ink-3);
}

.button {
  display: inline-block;
  padding: var(--s-3) var(--s-5);
  background: var(--accent);
  color: var(--accent-ink);
  border-radius: var(--r-sm);
  font-weight: 600;
  text-decoration: none;
}

.button:hover {
  background: color-mix(in srgb, var(--accent) 88%, var(--ink));
}

.contact {
  margin: 0;
}

.contact dt {
  color: var(--ink-2);
  font-size: var(--t-sm);
}

.contact dd {
  margin: 0 0 var(--s-5);
  font-size: var(--t-lg);
}

.foot {
  border-top: 1px solid var(--line);
  padding-block: var(--s-6);
  color: var(--ink-2);
  font-size: var(--t-sm);
}

.foot-inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3) var(--s-6);
}

.foot time {
  font-variant-numeric: tabular-nums;
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto;
  }
}

@media print {
  .bar,
  .skip,
  .button {
    display: none;
  }

  .band {
    padding-block: var(--s-6);
  }
}