:root {
  color-scheme: light;
  --ink: #1b1c19;
  --muted: #706f68;
  --paper: #f0eadf;
  --panel: #f8f4ec;
  --dark: #171914;
  --line: rgba(27, 28, 25, 0.16);
  --signal: #d8ff35;
  --danger: #b83a2d;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --sans: Inter, "Helvetica Neue", Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
}

body {
  margin: 0;
  min-width: 280px;
}

a {
  color: inherit;
}

button,
input,
select {
  font: inherit;
}

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--signal);
  color: var(--dark);
  transform: translateY(-180%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  min-height: 72px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 2rem;
  padding: 0 2.4vw;
  background: var(--dark);
  color: #f7f4eb;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.48rem;
  text-decoration: none;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
}

.brand em {
  color: var(--signal);
  font-style: normal;
}

.brand-mark {
  width: 22px;
  height: 22px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2px;
  align-items: end;
}

.brand-mark i {
  display: block;
  height: 48%;
  background: currentColor;
}

.brand-mark i:nth-child(2) {
  height: 100%;
}

.brand-mark i:nth-child(3) {
  height: 72%;
}

.reader-label,
.eyebrow,
label,
.reader-principle > span,
.reader-data header p,
.source-line,
footer {
  font-family: var(--mono);
  font-size: 0.69rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.reader-label {
  color: rgba(255, 255, 255, 0.54);
}

.back-link {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.78rem;
  text-decoration: none;
}

main {
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
  margin: 0 1.4vw;
}

.intro {
  min-height: 430px;
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr);
  grid-template-rows: auto 1fr;
  gap: 1.5rem 5vw;
  align-items: end;
  padding: clamp(3rem, 8vw, 7rem) clamp(1.4rem, 4vw, 4.5rem) 3rem;
  border-bottom: 1px solid var(--line);
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
}

.eyebrow {
  grid-column: 1 / -1;
  align-self: start;
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.eyebrow i {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 1px var(--ink);
}

.intro h1 {
  margin: 0;
  max-width: 950px;
  font-size: clamp(3.2rem, 7.2vw, 8rem);
  line-height: 0.86;
  letter-spacing: -0.07em;
}

.intro h1 em {
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 400;
}

.intro > p:not(.eyebrow) {
  align-self: end;
  margin: 0;
  max-width: 46ch;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.65;
}

.intro code {
  font-family: var(--mono);
  font-size: 0.86em;
}

.reader-principle {
  grid-column: 2;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  align-items: start;
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.reader-principle > span {
  padding: 0.35rem 0.48rem;
  background: var(--signal);
}

.reader-principle p {
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.55;
}

.reader-shell {
  display: grid;
  grid-template-columns: minmax(250px, 330px) minmax(0, 1fr);
  min-height: 720px;
}

.reader-controls {
  padding: 2rem;
  border-right: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.18);
}

.reader-controls form {
  display: grid;
  gap: 0.62rem;
}

.reader-controls label:not(:first-child) {
  margin-top: 1rem;
}

label span {
  color: var(--muted);
  font-size: 0.6rem;
}

input,
select {
  width: 100%;
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 0;
  padding: 0 0.8rem;
  background: var(--panel);
  color: var(--ink);
}

input:focus-visible,
select:focus-visible,
button:focus-visible,
a:focus-visible,
pre:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 2px;
}

.reader-controls button,
.reader-data button {
  min-height: 46px;
  border: 1px solid var(--dark);
  padding: 0 1rem;
  background: var(--dark);
  color: #fff;
  cursor: pointer;
}

.reader-controls button {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 1.1rem;
}

.reader-note {
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.reader-note strong {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.reader-note p {
  margin: 0.7rem 0 0;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.6;
}

.reader-data {
  min-width: 0;
  padding: 2rem;
  background: var(--panel);
}

.reader-data > header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: end;
  padding-bottom: 1.2rem;
}

.reader-data header p,
.reader-data h2 {
  margin: 0;
}

.reader-data header p {
  color: var(--muted);
}

.reader-data h2 {
  margin-top: 0.4rem;
  font-size: clamp(1.5rem, 2.5vw, 2.6rem);
  letter-spacing: -0.04em;
}

.reader-data button {
  background: transparent;
  color: var(--ink);
}

.reader-data button[data-copied="true"] {
  background: var(--signal);
}

.source-line {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.8rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  color: var(--muted);
}

.source-line code {
  font: inherit;
  text-transform: none;
  text-align: right;
}

pre {
  min-height: 560px;
  max-height: 72vh;
  overflow: auto;
  margin: 1.25rem 0 0;
  padding: clamp(1rem, 2.5vw, 2rem);
  border: 1px solid rgba(255, 255, 255, 0.09);
  background: var(--dark);
  color: #e8e9df;
  font: 0.78rem/1.65 var(--mono);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  tab-size: 2;
}

pre[data-error="true"] {
  color: #ffd4ce;
  border-color: var(--danger);
}

footer {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 2rem;
  align-items: center;
  min-height: 90px;
  padding: 1.5rem 2.4vw;
  background: var(--dark);
  color: #f7f4eb;
}

footer p {
  margin: 0;
  color: rgba(255, 255, 255, 0.55);
  text-align: center;
}

@media (max-width: 820px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .reader-label {
    display: none;
  }

  .intro {
    grid-template-columns: 1fr;
    min-height: 0;
  }

  .intro > * {
    grid-column: 1;
  }

  .reader-shell {
    grid-template-columns: 1fr;
  }

  .reader-controls {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  footer {
    grid-template-columns: 1fr;
    gap: 0.8rem;
    text-align: center;
  }
}

@media (max-width: 520px) {
  .site-header {
    min-height: 64px;
    padding: 0 1rem;
  }

  .back-link {
    font-size: 0.7rem;
  }

  main {
    margin: 0;
    border: 0;
  }

  .intro,
  .reader-controls,
  .reader-data {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .intro h1 {
    font-size: clamp(2.8rem, 15vw, 4.5rem);
  }

  .reader-principle {
    grid-template-columns: 1fr;
  }

  .reader-data > header,
  .source-line {
    align-items: stretch;
    flex-direction: column;
  }

  .source-line code {
    text-align: left;
  }

  pre {
    font-size: 0.7rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
  }
}