/* AlphaChrono website styles. One file, no build step.
   Colours are tokens on :root; the dark theme follows the system setting.
   No web fonts: system serif for reading, system sans for interface labels,
   system monospace for Bates numbers and text copied from records. */

:root {
  color-scheme: light dark;

  --paper: #fbfbf8;
  --paper-2: #f1f1ec;
  --sheet: #ffffff;
  --ink: #1a1e1d;
  --ink-2: #454d4a;
  --ink-3: #5d6662;
  --rule: #dcdfda;
  --rule-2: #c2c7c2;
  --accent: #0d6a5e;
  --accent-strong: #09504a;
  --accent-tint: #d8ece6;
  --accent-on: #ffffff;
  --shadow: 0 1px 2px rgb(20 30 28 / 0.06), 0 10px 28px -14px rgb(20 30 28 / 0.22);

  --serif: "Iowan Old Style", "Charter", "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Mono", "Segoe UI Mono", Consolas, Menlo, monospace;

  --measure: 40rem;
  --wide: 70rem;
  --gutter: clamp(1rem, 4vw, 2.5rem);
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #111514;
    --paper-2: #181d1b;
    --sheet: #1d2321;
    --ink: #e3e6e4;
    --ink-2: #b8bfbb;
    --ink-3: #98a09c;
    --rule: #2a302e;
    --rule-2: #3e4643;
    --accent: #6ec4b5;
    --accent-strong: #97d8cc;
    --accent-tint: #1a3f39;
    --accent-on: #0b1412;
    --shadow: 0 1px 2px rgb(0 0 0 / 0.4), 0 10px 28px -14px rgb(0 0 0 / 0.7);
  }
}

/* Base */

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

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

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 1.0625rem/1.6 var(--serif);
  font-kerning: normal;
  overflow-wrap: break-word;
}

h1,
h2,
h3 {
  font-weight: 400;
  line-height: 1.15;
  text-wrap: balance;
}

p,
li,
dd {
  text-wrap: pretty;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--accent-strong);
  text-decoration-thickness: 2px;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -3rem;
  z-index: 10;
  padding: 0.5rem 0.75rem;
  background: var(--ink);
  color: var(--paper);
  font: 600 0.875rem/1.4 var(--sans);
}

.skip-link:focus {
  top: 0.75rem;
  color: var(--paper);
}

.wrap {
  max-width: var(--wide);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* Short pages: main grows so the footer sits at the bottom of the window. */
body > main {
  flex: 1 0 auto;
  width: 100%;
}

/* Header */

.site-header {
  border-bottom: 1px solid var(--rule);
}

.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 2rem;
  padding-block: 1rem;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.3rem;
  letter-spacing: 0.005em;
  text-decoration: none;
}

.wordmark:hover {
  color: var(--ink);
}

.wordmark svg {
  width: 0.7rem;
  height: 1.4rem;
  color: var(--accent);
  flex: none;
}

.site-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font: 500 0.9375rem/1.4 var(--sans);
}

.site-nav a {
  display: inline-block;
  padding-block: 0.35rem;
  color: var(--ink-2);
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 2px;
  text-underline-offset: 0.45em;
}

/* Hero */

.hero {
  padding-block: clamp(3rem, 9vw, 6.5rem) clamp(2.25rem, 5vw, 3.5rem);
}

.hero h1 {
  max-width: 22ch;
  margin: 0 0 1.4rem;
  font-size: clamp(2.2rem, 1.3rem + 3.6vw, 3.6rem);
  letter-spacing: -0.012em;
  line-height: 1.08;
}

.lede {
  max-width: 37rem;
  margin: 0 0 2rem;
  color: var(--ink-2);
  font-size: clamp(1.125rem, 1rem + 0.45vw, 1.3rem);
  line-height: 1.55;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.5rem;
  margin: 0;
  font: 500 0.9375rem/1.4 var(--sans);
}

.button {
  display: inline-block;
  padding: 0.7rem 1.1rem;
  border-radius: 3px;
  background: var(--accent);
  color: var(--accent-on);
  font-weight: 600;
  text-decoration: none;
}

.button:hover {
  background: var(--accent-strong);
  color: var(--accent-on);
}

.status {
  margin: 1.5rem 0 0;
  color: var(--ink-3);
  font: 400 0.875rem/1.5 var(--sans);
}

/* Fig. 1: a chronology beside the source page */

.specimen {
  margin: 0 0 clamp(3rem, 7vw, 5rem);
}

.specimen-frame {
  display: grid;
  overflow: hidden;
  border: 1px solid var(--rule-2);
  border-radius: 4px;
  background: var(--paper-2);
}

.pane-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.25rem 1rem;
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--rule);
  color: var(--ink-3);
  font: 500 0.75rem/1.4 var(--sans);
}

.pane-bar strong {
  color: var(--ink);
  font-weight: 600;
}

.chron {
  border-bottom: 1px solid var(--rule-2);
  background: var(--paper);
}

.chron-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.entry {
  display: grid;
  grid-template-columns: 6rem minmax(0, 1fr);
  gap: 0.2rem 1rem;
  padding: 0.95rem 1rem;
  border-bottom: 1px solid var(--rule);
}

.entry:last-child {
  border-bottom: 0;
}

.entry.is-active {
  background: var(--paper-2);
  box-shadow: inset 3px 0 0 var(--accent);
}

.entry-date {
  color: var(--ink);
  font: 600 0.8125rem/1.5 var(--sans);
  font-variant-numeric: tabular-nums;
}

.entry-meta {
  margin: 0;
  color: var(--ink-3);
  font: 400 0.75rem/1.5 var(--sans);
}

.entry-quote {
  margin: 0.35rem 0 0.6rem;
  padding-left: 0.7rem;
  border-left: 2px solid var(--rule-2);
  color: var(--ink);
  font: 400 0.8125rem/1.5 var(--mono);
}

.entry-quote p {
  margin: 0;
}

.entry-foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
}

.entry-gap .entry-date {
  color: var(--ink-3);
  font-weight: 500;
}

.entry-note {
  margin: 0.35rem 0 0;
  color: var(--ink-3);
  font: italic 400 0.8125rem/1.5 var(--sans);
}

.bates {
  padding: 0.3rem 0.45rem;
  border: 1px solid currentColor;
  border-radius: 3px;
  background: transparent;
  color: var(--accent);
  font: 500 0.75rem/1 var(--mono);
  letter-spacing: 0.02em;
  cursor: pointer;
}

.bates::after {
  content: " \2192";
  content: " \2192" / "";
}

.bates:hover {
  color: var(--accent-strong);
}

.bates[aria-pressed="true"] {
  border-color: var(--accent);
  background: var(--accent);
  color: var(--accent-on);
}

.flag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.2rem 0.45rem;
  border: 1px dashed var(--ink-3);
  border-radius: 2px;
  color: var(--ink-2);
  font: 500 0.75rem/1.2 var(--sans);
}

.flag::before,
.flags dt::before {
  content: "";
  flex: none;
  width: 0.4rem;
  height: 0.4rem;
  border: 1.5px solid currentColor;
  transform: rotate(45deg);
}

.source {
  padding: 0 1rem 1.25rem;
}

.page[hidden] {
  display: none;
}

.page .pane-bar {
  margin-inline: -1rem;
  margin-bottom: 1rem;
}

.page-id {
  color: var(--ink);
  font-family: var(--mono);
  font-weight: 600;
}

.sheet {
  position: relative;
  min-height: 23rem;
  padding: 1.25rem 1.25rem 3rem;
  border: 1px solid var(--rule);
  background: var(--sheet);
  box-shadow: var(--shadow);
  color: var(--ink-2);
  font: 400 0.75rem/1.65 var(--mono);
}

.sheet p {
  margin: 0 0 0.6rem;
}

.sheet-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0 1rem;
  padding-bottom: 0.5rem;
  margin-bottom: 0.75rem;
  border-bottom: 1px solid var(--ink-2);
  color: var(--ink);
  font-weight: 700;
  letter-spacing: 0.03em;
}

.sheet .label {
  color: var(--ink);
  font-weight: 700;
}

.sheet mark {
  padding: 0.05em 0.15em;
  background: var(--accent-tint);
  box-shadow: inset 0 -2px 0 var(--accent);
  color: var(--ink);
}

.sheet .stamp {
  position: absolute;
  right: 1rem;
  bottom: 0.9rem;
  margin: 0;
  color: var(--ink);
  font-weight: 700;
  letter-spacing: 0.06em;
}

.sheet.is-scan {
  transform: rotate(-0.5deg);
  color: var(--ink-3);
  text-shadow: 0 0 0.6px currentColor;
}

.illegible {
  display: inline-block;
  width: 1.3em;
  height: 0.9em;
  vertical-align: -0.1em;
  border-radius: 40%;
  background: var(--rule-2);
}

.specimen figcaption {
  max-width: 46rem;
  margin-top: 0.85rem;
  color: var(--ink-3);
  font: 400 0.8125rem/1.55 var(--sans);
}

.fig-label {
  margin-right: 0.35rem;
  color: var(--ink);
  font-weight: 600;
}

.js-only {
  display: none;
}

.js .js-only {
  display: inline;
}

@media (min-width: 56rem) {
  .specimen-frame {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  }

  .chron {
    border-right: 1px solid var(--rule-2);
    border-bottom: 0;
  }

  .source {
    padding: 0 1.5rem 1.5rem;
  }

  .page .pane-bar {
    margin-inline: -1.5rem;
    padding-inline: 1.5rem;
    margin-bottom: 1.5rem;
  }
}

@media (max-width: 30rem) {
  .entry {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* Numbered sections */

.section {
  padding-block: clamp(2.5rem, 6vw, 4.5rem);
  border-top: 1px solid var(--rule);
}

.section-grid {
  display: grid;
  gap: 0.75rem 3rem;
}

@media (min-width: 52rem) {
  .section-grid {
    grid-template-columns: 11rem minmax(0, 1fr);
  }
}

.section-label {
  margin: 0;
  padding-top: 0.5rem;
  color: var(--ink-3);
  font: 500 0.8125rem/1.5 var(--sans);
  letter-spacing: 0.01em;
}

.section-label .num {
  margin-right: 0.6rem;
  color: var(--accent);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

.section-body {
  max-width: var(--measure);
}

.section-body > :last-child {
  margin-bottom: 0;
}

.section-body h2 {
  margin: 0 0 1.25rem;
  font-size: clamp(1.55rem, 1.2rem + 1.3vw, 2.1rem);
  letter-spacing: -0.005em;
}

.section-body p {
  margin: 0 0 1rem;
}

.rule-statement {
  margin: 0 0 1.5rem;
  padding-left: 1.1rem;
  border-left: 3px solid var(--accent);
}

.section-body h2.rule-statement {
  font-size: clamp(1.7rem, 1.25rem + 1.8vw, 2.45rem);
  line-height: 1.15;
}

/* Who it's for */

.audience {
  display: grid;
  gap: 1.75rem 2.5rem;
  margin-top: 2rem;
}

@media (min-width: 40rem) {
  .audience {
    grid-template-columns: 1fr 1fr;
  }
}

.audience h3 {
  margin: 0 0 0.4rem;
  padding-top: 0.85rem;
  border-top: 2px solid var(--ink);
  font: 600 1rem/1.4 var(--sans);
}

.audience p {
  margin: 0;
  color: var(--ink-2);
}

/* How it works */

.steps {
  margin: 1.75rem 0 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.steps li {
  display: grid;
  grid-template-columns: 2.25rem minmax(0, 1fr);
  padding-block: 1.25rem;
  border-top: 1px solid var(--rule);
  counter-increment: step;
}

.steps li::before {
  content: counter(step);
  grid-row: 1 / span 2;
  color: var(--accent);
  font: 600 0.9375rem/1.75 var(--sans);
  font-variant-numeric: tabular-nums;
}

.steps h3 {
  margin: 0 0 0.35rem;
  font-size: 1.2rem;
  font-weight: 600;
  line-height: 1.35;
}

.steps p {
  margin: 0;
  color: var(--ink-2);
}

/* Review flags */

.flags {
  display: grid;
  margin: 1.75rem 0 0;
  column-gap: 2rem;
}

@media (min-width: 40rem) {
  .flags {
    grid-template-columns: 1fr 1fr;
  }
}

.flags div {
  padding-block: 1rem;
  border-top: 1px solid var(--rule);
}

.flags dt {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.3rem;
  font: 600 0.9375rem/1.4 var(--sans);
}

.flags dt::before {
  color: var(--ink-3);
}

.flags dd {
  margin: 0;
  color: var(--ink-2);
  font-size: 1rem;
}

/* Boxed notices: availability, contact warning */

.notice {
  max-width: var(--measure);
  padding-block: 1.1rem 1.25rem;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--rule-2);
}

.notice h2 {
  margin: 0 0 0.6rem;
  font: 600 1.05rem/1.4 var(--sans);
}

.notice p {
  margin: 0 0 0.75rem;
  color: var(--ink-2);
}

.notice > :last-child {
  margin-bottom: 0;
}

.email-link {
  font-size: clamp(1.35rem, 1.1rem + 1.2vw, 1.85rem);
  overflow-wrap: anywhere;
}

/* Inner pages */

.page-head {
  padding-block: clamp(2.5rem, 7vw, 5rem) clamp(1.5rem, 4vw, 2.5rem);
}

.page-head h1 {
  margin: 0 0 1rem;
  font-size: clamp(2rem, 1.4rem + 2.6vw, 3rem);
  letter-spacing: -0.01em;
}

.page-head .lede {
  margin-bottom: 0;
}

.principles {
  margin: 0;
  padding: 0;
  list-style: none;
}

.principles li {
  padding: 0.75rem 0 0.75rem 1.5rem;
  border-top: 1px solid var(--rule);
  position: relative;
}

.principles li::before {
  content: "\2014";
  position: absolute;
  left: 0;
  color: var(--accent);
}

/* Draft legal pages */

.draft-banner {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.75rem;
  align-items: baseline;
  margin: clamp(1.5rem, 4vw, 2.5rem) 0 0;
  padding: 0.75rem 1rem;
  border: 1px dashed var(--ink-3);
  color: var(--ink-2);
  font: 400 0.875rem/1.5 var(--sans);
}

.draft-banner strong {
  color: var(--ink);
  font: 700 0.8125rem/1.5 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.doc {
  max-width: var(--measure);
  padding-bottom: 1rem;
  counter-reset: clause;
}

.doc h2 {
  margin: 2.25rem 0 0.5rem;
  font-size: 1.3rem;
  font-weight: 600;
  counter-increment: clause;
}

.doc h2::before {
  content: counter(clause) ".";
  display: inline-block;
  min-width: 1.75rem;
  color: var(--accent);
  font: 600 1rem/1 var(--sans);
}

.doc p {
  margin: 0 0 1rem;
}

.doc-date {
  margin: 0;
  color: var(--ink-3);
  font: 400 0.875rem/1.5 var(--sans);
}

/* Page stamp and footer */

.page-stamp {
  margin: clamp(3rem, 7vw, 5rem) 0 1.25rem;
  color: var(--ink-3);
  font: 500 0.75rem/1 var(--mono);
  letter-spacing: 0.08em;
  text-align: right;
  text-transform: uppercase;
}

.site-footer {
  border-top: 1px solid var(--rule);
  background: var(--paper-2);
  color: var(--ink-2);
  font: 400 0.875rem/1.6 var(--sans);
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1.5rem 3rem;
  padding-block: 2rem 1.5rem;
}

.footer-top p {
  margin: 0.4rem 0 0;
  max-width: 24rem;
}

.site-footer .wordmark {
  font-size: 1.1rem;
}

.site-footer ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-footer nav a {
  display: inline-block;
  padding-block: 0.2rem;
  color: var(--ink-2);
}

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

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.25rem 2rem;
  padding-block: 1rem 2rem;
  border-top: 1px solid var(--rule);
  color: var(--ink-3);
  font-size: 0.8125rem;
}

.footer-bottom p {
  margin: 0;
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}