:root {
  --paper: #e6ebea;
  --ink: #0f2338;
  --graphite: #50606e;
  --rule: #c2cdce;
  --mark: #f2c200;
  --on-mark: #0f2338;
  --danger: #9e2418;
  --focus: #0f2338;
  --well: #dbe2e1;

  --font: "Archivo", "Helvetica Neue", Arial, sans-serif;
  --measure: 38rem;
  --page: 72rem;
  --gutter: clamp(1rem, 4vw, 3rem);
  --duration: 180ms;
  --ease: cubic-bezier(0.2, 0, 0, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #0d1722;
    --ink: #dce6ea;
    --graphite: #8e9daa;
    --rule: #24364a;
    --mark: #e0b400;
    --on-mark: #0d1722;
    --danger: #f08a7a;
    --focus: #dce6ea;
    --well: #132131;
  }
}

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font);
  font-size: 1.125rem;
  line-height: 1.55;
  font-variation-settings: "wdth" 100;
  font-variant-numeric: tabular-nums;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

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

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.site-header,
main > section,
.site-footer {
  max-width: var(--page);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* Header */

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem 2rem;
  padding-block: 1.5rem;
}

.wordmark {
  font-weight: 700;
  font-variation-settings: "wdth" 125;
  font-size: 1.125rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.5rem;
  font-size: 0.9375rem;
}

.site-nav a {
  color: var(--graphite);
  text-decoration: none;
  white-space: nowrap;
}

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

/* Hero */

.hero {
  padding-block: clamp(2rem, 6vw, 4.5rem) 3rem;
}

h1 {
  margin: 0;
  max-width: 16ch;
  font-size: clamp(2.5rem, 6.4vw, 4.75rem);
  line-height: 0.98;
  font-weight: 800;
  font-variation-settings: "wdth" 125;
  letter-spacing: -0.02em;
  text-wrap: balance;
}

.lede {
  max-width: var(--measure);
  margin: 1.5rem 0 2.5rem;
  font-size: 1.25rem;
  line-height: 1.5;
}

/* Sonogram */

.sonogram {
  display: grid;
  grid-template-columns: 1.5rem minmax(0, 1fr) 3.75rem;
  grid-template-areas:
    "lanes well scale"
    ". caption caption";
  column-gap: 0.5rem;
  margin: 0;
}

.sonogram-well {
  grid-area: well;
  position: relative;
  height: clamp(13rem, 30vw, 21rem);
  border-block: 1px solid var(--ink);
}

#sonogram-canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.sonogram-lanes,
.sonogram-scale {
  position: relative;
  height: clamp(13rem, 30vw, 21rem);
  font-size: 0.6875rem;
  line-height: 1;
  color: var(--graphite);
}

.sonogram-lanes {
  grid-area: lanes;
  text-align: right;
}

.sonogram-scale {
  grid-area: scale;
}

.sonogram-lanes span,
.sonogram-scale span {
  position: absolute;
  inset-inline: 0;
  transform: translateY(-50%);
  white-space: nowrap;
}

.sonogram-scale span::before {
  content: "";
  display: inline-block;
  width: 0.375rem;
  height: 1px;
  margin-right: 0.3rem;
  vertical-align: middle;
  background: var(--graphite);
}

.sonogram figcaption {
  grid-area: caption;
  max-width: var(--measure);
  margin-top: 0.75rem;
  font-size: 0.9375rem;
  color: var(--graphite);
}

/* Console */

.console {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  grid-template-areas:
    "compose listen"
    "compose heard";
  gap: 1.5rem 3rem;
  margin-top: 2.5rem;
  margin-left: 2rem;
}

.compose {
  grid-area: compose;
}

.compose label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.compose-row {
  display: flex;
  gap: 0.75rem;
}

#message {
  flex: 1;
  min-width: 0;
  padding: 0.7rem 0.85rem;
  font: inherit;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--ink);
  border-radius: 2px;
}

.help {
  margin: 0.5rem 0 0;
  font-size: 0.9375rem;
  color: var(--graphite);
}

.help.is-error {
  color: var(--danger);
}

.button {
  padding: 0.7rem 1.4rem;
  font: inherit;
  font-weight: 700;
  font-variation-settings: "wdth" 112;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--ink);
  border-radius: 2px;
  cursor: pointer;
  white-space: nowrap;
  transition:
    background-color var(--duration) var(--ease),
    color var(--duration) var(--ease);
}

.button-primary,
.button[aria-pressed="true"] {
  color: var(--paper);
  background: var(--ink);
}

.button:disabled {
  cursor: progress;
  opacity: 0.6;
}

.listen {
  grid-area: listen;
  align-self: end;
}

.heard {
  grid-area: heard;
}

.heard-title {
  margin: 0 0 0.5rem;
  font-size: 1rem;
  font-weight: 600;
  font-variation-settings: "wdth" 100;
}

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

.heard-list li {
  padding-block: 0.5rem;
  border-top: 1px solid var(--rule);
}

.heard-text {
  padding: 0.05em 0.25em;
  margin-left: -0.25em;
  color: var(--on-mark);
  background: var(--mark);
  box-decoration-break: clone;
  -webkit-box-decoration-break: clone;
  overflow-wrap: anywhere;
}

.heard-meta {
  display: block;
  margin-top: 0.15rem;
  font-size: 0.8125rem;
  color: var(--graphite);
}

.heard-list .is-failed {
  color: var(--danger);
  font-size: 0.9375rem;
}

.heard-empty {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--graphite);
}

.heard-list:not(:empty) + .heard-empty {
  display: none;
}

/* Lower sections */

.band {
  padding-block: 3.5rem;
  border-top: 1px solid var(--rule);
}

h2 {
  margin: 0 0 1.5rem;
  font-size: clamp(1.625rem, 3vw, 2.25rem);
  line-height: 1.1;
  font-weight: 700;
  font-variation-settings: "wdth" 118;
  letter-spacing: -0.01em;
}

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

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 2rem 3rem;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.steps li {
  counter-increment: step;
  font-size: 1rem;
}

.steps li::before {
  content: counter(step);
  display: block;
  margin-bottom: 0.5rem;
  font-size: 2.25rem;
  line-height: 1;
  font-weight: 800;
  font-variation-settings: "wdth" 125;
}

.step-title {
  font-weight: 700;
}

.frame-figure {
  margin: 2rem 0 2.5rem;
}

.frame-scroll {
  overflow-x: auto;
}

.frame-diagram {
  display: block;
  width: 100%;
  min-width: 34rem;
  max-width: 54rem;
  height: auto;
  font-family: var(--font);
}

.frame-diagram .lane {
  stroke: var(--rule);
  stroke-width: 1;
}

.frame-diagram .tone {
  fill: var(--ink);
}

.frame-diagram .bracket {
  fill: none;
  stroke: var(--graphite);
  stroke-width: 1;
}

.frame-diagram .bracket-label {
  fill: var(--ink);
  font-size: 13px;
  font-weight: 600;
}

.frame-diagram .digit {
  fill: var(--graphite);
  font-size: 11px;
}

.frame-figure figcaption {
  margin-top: 0.75rem;
  font-size: 0.9375rem;
  color: var(--graphite);
}

.hex {
  color: var(--ink);
  word-spacing: 0.15em;
}

.params {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 3rem;
  max-width: 54rem;
  margin: 0 0 2rem;
}

.params div {
  display: grid;
  grid-template-columns: 9rem minmax(0, 1fr);
  gap: 1rem;
  padding-block: 0.65rem;
  border-top: 1px solid var(--rule);
}

.params dt {
  color: var(--graphite);
}

.params dd {
  margin: 0;
}

.code {
  max-width: 46rem;
  margin: 1.5rem 0 0.75rem;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.875rem;
  line-height: 1.7;
  border-left: 3px solid var(--ink);
  background: var(--well);
}

.limits {
  max-width: var(--measure);
  margin: 0;
  padding: 0;
  list-style: none;
}

.limits li {
  margin-bottom: 1.25rem;
}

.limits strong {
  display: block;
  font-variation-settings: "wdth" 112;
}

.site-footer {
  padding-block: 2rem 3rem;
  border-top: 1px solid var(--rule);
  font-size: 0.9375rem;
  color: var(--graphite);
}

.site-footer p {
  margin: 0;
}

/* Narrow screens */

@media (max-width: 860px) {
  .console {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "compose"
      "listen"
      "heard";
    margin-left: 0;
  }

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

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

@media (max-width: 560px) {
  body {
    font-size: 1.0625rem;
  }

  .lede {
    font-size: 1.125rem;
  }

  .sonogram {
    grid-template-columns: 1rem minmax(0, 1fr) 3.5rem;
    column-gap: 0.375rem;
  }

  .sonogram-lanes span:nth-child(even) {
    display: none;
  }

  .compose-row {
    flex-wrap: wrap;
  }

  .compose-row .button {
    flex: 1 0 100%;
  }

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

  .params div {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .button {
    transition: none;
  }
}