:root {
  --bg: #fdfdfc;
  --surface: #ffffff;
  --text: #1f2328;
  --text-muted: #5c6570;
  --border: #e2e4e8;
  --border-strong: #cfd3d9;
  --link: #1a56b8;
  --link-hover: #113a80;
  --focus: #1a56b8;
  --space: 1rem;
  --measure: 42rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171a;
    --surface: #1c2024;
    --text: #e6e8ea;
    --text-muted: #9aa4ae;
    --border: #2c3238;
    --border-strong: #3d454d;
    --link: #79b0ff;
    --link-hover: #a6cbff;
    --focus: #79b0ff;
  }
}

* {
  box-sizing: border-box;
}

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

body {
  margin: 0 auto;
  padding: calc(var(--space) * 2) var(--space) calc(var(--space) * 3);
  max-width: var(--measure);
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
}

/* --- Links ------------------------------------------------------------ */

a {
  color: var(--link);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

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

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

/* --- Breadcrumb ------------------------------------------------------- */

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.5rem;
  margin: 0 0 calc(var(--space) * 2);
  padding: 0;
  list-style: none;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.breadcrumb li + li::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--border-strong);
}

.breadcrumb [aria-current="page"] {
  color: var(--text-muted);
}

/* --- Typography ------------------------------------------------------- */

h1 {
  margin: 0 0 0.5rem;
  font-size: 1.875rem;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

h2 {
  margin: calc(var(--space) * 2) 0 0.5rem;
  font-size: 1.3125rem;
  line-height: 1.3;
}

h3 {
  margin: calc(var(--space) * 1.5) 0 0.375rem;
  font-size: 1.0625rem;
}

p {
  margin: 0 0 var(--space);
}

.lede {
  color: var(--text-muted);
  font-size: 1.125rem;
  margin-bottom: calc(var(--space) * 2);
}

main ul,
main ol {
  margin: 0 0 var(--space);
  padding-left: 1.5rem;
}

main li {
  margin-bottom: 0.25rem;
}

strong {
  font-weight: 600;
}

code {
  padding: 0.1em 0.35em;
  border-radius: 3px;
  background: var(--surface);
  border: 1px solid var(--border);
  font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
  font-size: 0.9em;
}

blockquote {
  margin: 0 0 var(--space);
  padding-left: var(--space);
  border-left: 3px solid var(--border-strong);
  color: var(--text-muted);
}

hr {
  margin: calc(var(--space) * 2) 0;
  border: 0;
  border-top: 1px solid var(--border);
}

/* --- Tables ----------------------------------------------------------- */

.table-wrap {
  margin: 0 0 var(--space);
  overflow-x: auto;
}

table {
  border-collapse: collapse;
  width: 100%;
  min-width: 22rem;
  font-size: 0.9375rem;
}

th,
td {
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

th {
  background: var(--surface);
  font-weight: 600;
}

/* --- Screenshots ------------------------------------------------------ */

main img {
  max-width: 100%;
  height: auto;
}

.shots {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space);
  margin: 0 0 calc(var(--space) * 1.5);
}

.shots img {
  display: block;
  min-width: 0;
  border: 1px solid var(--border);
  border-radius: 10px;
}

/* Two screenshots of the same shape, side by side; stacked when narrow. */
.shots.pair img {
  flex: 1 1 14rem;
}

/* --- Chapter navigation ----------------------------------------------- */

.chapter-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem var(--space);
  margin-top: calc(var(--space) * 2.5);
  padding-top: var(--space);
  border-top: 1px solid var(--border);
  font-size: 0.9375rem;
}

/* --- Card list (index pages) ------------------------------------------ */

.card-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.75rem;
}

.card-list li {
  margin: 0;
}

.card-list a {
  display: block;
  padding: 0.875rem 1rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  color: inherit;
  text-decoration: none;
}

.card-list a:hover {
  border-color: var(--border-strong);
}

.card-list .title {
  display: block;
  font-weight: 600;
  color: var(--link);
}

.card-list a:hover .title {
  color: var(--link-hover);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.card-list .desc {
  display: block;
  margin-top: 0.125rem;
  font-size: 0.9375rem;
  color: var(--text-muted);
}

/* --- Footer ----------------------------------------------------------- */

footer {
  margin-top: calc(var(--space) * 3);
  padding-top: var(--space);
  border-top: 1px solid var(--border);
  font-size: 0.875rem;
  color: var(--text-muted);
}

footer p {
  margin: 0;
}