/* Meridian showcase — "instrument sheet".
   A calibration certificate crossed with a lab notebook: warm paper, ink,
   hairline rules, numbers set in mono. Colour carries meaning only:
   pass / regression / warning / baseline / head. */

:root {
  color-scheme: light;
  --paper: #f5f2ea;
  --paper-2: #ece7db;
  --paper-3: #e2dccd;
  --ink: #1a1915;
  --ink-2: #45423a;
  --ink-3: #5f5b50;
  --rule: #cfc8b7;
  --rule-strong: #1a1915;
  --grid-line: rgb(26 25 21 / 0.05);

  --pass: #17634a;
  --pass-fill: #2f8f6b;
  --pass-wash: #dbeadf;
  --fail: #a8231b;
  --fail-fill: #c9372c;
  --fail-wash: #f4dcd6;
  --warn: #7d5100;
  --warn-fill: #d2951c;
  --warn-wash: #f3e5c4;
  --base: #5f5b50;
  --head: #1d4aa0;
  --accent: #1d4aa0;
  --accent-wash: #dde5f4;
  --focus: #1d4aa0;

  --font-serif: "Newsreader", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: clamp(1.02rem, 0.97rem + 0.25vw, 1.15rem);
  --text-lg: clamp(1.2rem, 1.08rem + 0.5vw, 1.45rem);
  --text-xl: clamp(1.6rem, 1.3rem + 1.4vw, 2.4rem);
  --text-hero: clamp(2.4rem, 1.5rem + 3.6vw, 4.6rem);
  --text-figure: clamp(2.4rem, 1.8rem + 2.6vw, 3.8rem);

  --gutter: clamp(1rem, 0.6rem + 2vw, 2.5rem);
  --space-section: clamp(3.5rem, 2.5rem + 4vw, 7rem);
  --measure: 64ch;
  --page: 1200px;

  --radius-s: 2px;
  --radius-m: 6px;
  --shadow-sheet: 0 1px 0 rgb(26 25 21 / 0.06), 0 12px 32px -18px rgb(26 25 21 / 0.35);

  --duration-fast: 140ms;
  --duration-normal: 320ms;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --paper: #12130f;
    --paper-2: #1b1c17;
    --paper-3: #25261f;
    --ink: #ece7da;
    --ink-2: #c3bdae;
    --ink-3: #a19b8b;
    --rule: #3a3a32;
    --rule-strong: #ece7da;
    --grid-line: rgb(236 231 218 / 0.045);
    --pass: #6fd0a6;
    --pass-fill: #4fb78b;
    --pass-wash: #173127;
    --fail: #ff8a7d;
    --fail-fill: #ec5f51;
    --fail-wash: #3a1b17;
    --warn: #f0bd5a;
    --warn-fill: #d9a032;
    --warn-wash: #372a10;
    --base: #a19b8b;
    --head: #93b4ff;
    --accent: #93b4ff;
    --accent-wash: #1c2640;
    --focus: #93b4ff;
    --shadow-sheet: 0 1px 0 rgb(0 0 0 / 0.4), 0 16px 40px -20px rgb(0 0 0 / 0.8);
    --band-opacity: 0.3;
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #12130f;
  --paper-2: #1b1c17;
  --paper-3: #25261f;
  --ink: #ece7da;
  --ink-2: #c3bdae;
  --ink-3: #a19b8b;
  --rule: #3a3a32;
  --rule-strong: #ece7da;
  --grid-line: rgb(236 231 218 / 0.045);
  --pass: #6fd0a6;
  --pass-fill: #4fb78b;
  --pass-wash: #173127;
  --fail: #ff8a7d;
  --fail-fill: #ec5f51;
  --fail-wash: #3a1b17;
  --warn: #f0bd5a;
  --warn-fill: #d9a032;
  --warn-wash: #372a10;
  --base: #a19b8b;
  --head: #93b4ff;
  --accent: #93b4ff;
  --accent-wash: #1c2640;
  --focus: #93b4ff;
  --shadow-sheet: 0 1px 0 rgb(0 0 0 / 0.4), 0 16px 40px -20px rgb(0 0 0 / 0.8);
  --band-opacity: 0.3;
}

/* ---------- base ---------- */

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: var(--text-base);
  line-height: 1.55;
  font-optical-sizing: auto;
  overflow-x: hidden;
}

img,
svg {
  display: block;
  max-width: 100%;
}

figure {
  margin: 0;
}

a {
  color: inherit;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 1.5px;
  text-underline-offset: 0.18em;
  transition: color var(--duration-fast) ease, text-decoration-color var(--duration-fast) ease;
}

a:hover {
  color: var(--accent);
}

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

code,
kbd,
pre,
.mono {
  font-family: var(--font-mono);
  font-size: 0.86em;
  font-variant-numeric: tabular-nums;
}

p {
  margin: 0 0 1em;
  max-width: var(--measure);
}

h1,
h2,
h3 {
  font-weight: 500;
  line-height: 1.08;
  letter-spacing: -0.015em;
  margin: 0;
  text-wrap: balance;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--ink);
  color: var(--paper);
  padding: 0.5rem 0.9rem;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  z-index: 10;
}

.skip-link:focus {
  top: 1rem;
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.wrap {
  width: 100%;
  max-width: var(--page);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.t-pass { color: var(--pass); }
.t-fail { color: var(--fail); }
.t-warn { color: var(--warn); }
.t-muted { color: var(--ink-3); }

/* ---------- masthead ---------- */

.masthead {
  border-bottom: 1px solid var(--rule-strong);
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 24px 24px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding-block: 1rem;
  border-bottom: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

.wordmark {
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  text-decoration: none;
}

.topbar nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.topbar nav a {
  text-decoration: none;
  color: var(--ink-2);
  padding: 0.25rem 0;
  border-bottom: 1px solid transparent;
}

.topbar nav a:hover {
  color: var(--ink);
  border-bottom-color: var(--accent);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: clamp(2rem, 4vw, 4.5rem);
  padding-block: clamp(2.5rem, 2rem + 4vw, 5rem) clamp(2.5rem, 2rem + 3vw, 4rem);
  align-items: center;
}

.hero h1 {
  font-size: var(--text-hero);
  font-weight: 400;
  letter-spacing: -0.03em;
  line-height: 0.98;
}

.hero h1 em {
  font-style: italic;
  color: var(--ink-2);
}

.hero .lede {
  margin-top: 1.5rem;
  font-size: var(--text-lg);
  color: var(--ink-2);
  max-width: 46ch;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  padding: 0.7rem 1.05rem;
  border: 1px solid var(--rule-strong);
  border-radius: var(--radius-s);
  text-decoration: none;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background var(--duration-fast) ease, color var(--duration-fast) ease,
    transform var(--duration-fast) ease;
}

.btn:hover {
  background: var(--ink);
  color: var(--paper);
}

.btn:active {
  transform: translateY(1px);
}

.btn.primary {
  background: var(--ink);
  color: var(--paper);
}

.btn.primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper);
}

/* the specimen: a gate comment, pinned to the page like a printout */
.specimen {
  background: var(--paper);
  border: 1px solid var(--rule-strong);
  box-shadow: var(--shadow-sheet);
  transform: rotate(-0.6deg);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  position: relative;
}

.specimen header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.25rem 1rem;
  white-space: nowrap;
  padding: 0.6rem 0.9rem;
  border-bottom: 1px solid var(--rule);
  color: var(--ink-3);
  font-size: var(--text-xs);
}

.specimen .body {
  padding: 1rem 0.9rem 1.1rem;
}

.stamp {
  display: inline-block;
  font-weight: 600;
  letter-spacing: 0.14em;
  padding: 0.15rem 0.5rem;
  border: 2px solid currentColor;
  border-radius: var(--radius-s);
}

.stamp.fail { color: var(--fail); }
.stamp.pass { color: var(--pass); }
.stamp.pass_with_warning { color: var(--warn); }
.stamp.inconclusive { color: var(--warn); }

.specimen .reason {
  margin: 0.75rem 0;
  line-height: 1.5;
}

.specimen .sens {
  border-top: 1px dashed var(--rule);
  padding-top: 0.75rem;
  color: var(--ink-2);
  line-height: 1.5;
  margin: 0;
}

.readouts {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: 1px solid var(--rule);
}

.readout {
  padding: 1.25rem 1rem 1.4rem 0;
  border-right: 1px solid var(--rule);
}

.readout + .readout {
  padding-left: 1rem;
}

.readout:last-child {
  border-right: 0;
}

.readout dd {
  margin: 0;
}

.readout .figure {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.readout .figure small {
  font-size: 0.45em;
  letter-spacing: 0;
  color: var(--ink-3);
}

.readout p {
  font-size: var(--text-sm);
  color: var(--ink-2);
  margin: 0.55rem 0 0;
}

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

.section {
  padding-block: var(--space-section) 0;
}

.section-head {
  display: grid;
  grid-template-columns: 5.5rem minmax(0, 1fr);
  gap: 0 1.5rem;
  border-top: 1px solid var(--rule-strong);
  padding-top: 1rem;
  margin-bottom: clamp(1.75rem, 3vw, 2.75rem);
}

.section-head .no {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--ink-3);
  padding-top: 0.45rem;
}

.section-head h2 {
  font-size: var(--text-xl);
}

.section-head .kicker {
  grid-column: 2;
  margin-top: 0.9rem;
  color: var(--ink-2);
  font-size: var(--text-lg);
  max-width: 52ch;
}

.body-offset {
  margin-left: calc(5.5rem + 1.5rem);
}