/* Shared styles. The "broken" and "fixed" demo pages use the SAME classes,
   so they look identical — only the underlying HTML structure differs. */

:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --text: #1d1d1f;
  --muted: #55555c;
  --border: #dcd9d2;
  --accent: #1f5fa8;
  --accent-text: #ffffff;
  --brand: #2e5d3a;
  --warn-bg: #fff4d6;
  --warn-border: #c98a00;
  --bad-bg: #fde7e7;
  --bad-border: #b3261e;
  --good-bg: #e3f4e6;
  --good-border: #2e7d32;
  --focus: #c2410c;
  --radius: 10px;
  --max: 68rem;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16171a;
    --surface: #1f2024;
    --text: #ececef;
    --muted: #a8a8b3;
    --border: #3a3b41;
    --accent: #7fb2f0;
    --accent-text: #0e1116;
    --brand: #8fd19e;
    --warn-bg: #3a2f10;
    --warn-border: #e0a82e;
    --bad-bg: #3d1a1a;
    --bad-border: #f2827b;
    --good-bg: #16331c;
    --good-border: #7bd389;
    --focus: #ffb37a;
    color-scheme: dark;
  }
}

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

html { font-size: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 1.0625rem/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

a { color: var(--accent); }
a:focus-visible, button:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

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

code, kbd {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
}
kbd {
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 0 0.35em;
  background: var(--surface);
  white-space: nowrap;
}

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 1rem; }

.skip-link {
  position: absolute;
  left: 1rem;
  top: -10rem;
  background: var(--accent);
  color: var(--accent-text);
  padding: 0.6rem 1rem;
  border-radius: var(--radius);
  z-index: 100;
}
.skip-link:focus { top: 1rem; }

/* ---------- Workshop pages (index, cheat sheet, exercises) ---------- */

.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  align-items: center;
  justify-content: space-between;
  padding-block: 0.9rem;
}
.site-title { font-weight: 700; text-decoration: none; color: var(--text); }
.site-nav ul { display: flex; flex-wrap: wrap; gap: 0.25rem 1rem; list-style: none; margin: 0; padding: 0; }

.page { padding-block: 2rem 3rem; }
.page h1 { font-size: clamp(1.8rem, 4vw, 2.6rem); line-height: 1.2; margin-top: 0; }
.page h2 { margin-top: 2.5rem; font-size: 1.5rem; }
.page h3 { margin-top: 1.5rem; font-size: 1.2rem; }

.lede { font-size: 1.2rem; color: var(--muted); max-width: 46rem; }

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  gap: 1rem;
  margin: 2rem 0;
  padding: 0;
  list-style: none;
}
.stats li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
}
.stats strong { display: block; font-size: 2.4rem; line-height: 1; color: var(--accent); }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(17rem, 1fr));
  gap: 1rem;
  padding: 0;
  list-style: none;
}
.cards li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
}
.cards h3 { margin-top: 0; }

.callout {
  border-left: 4px solid var(--warn-border);
  background: var(--warn-bg);
  padding: 0.9rem 1.1rem;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.5rem 0;
}
.callout.good { border-color: var(--good-border); background: var(--good-bg); }
.callout.bad { border-color: var(--bad-border); background: var(--bad-bg); }
.callout > :first-child { margin-top: 0; }
.callout > :last-child { margin-bottom: 0; }

.table-scroll { overflow-x: auto; margin: 1rem 0; }
table { border-collapse: collapse; width: 100%; min-width: 32rem; background: var(--surface); }
th, td { border: 1px solid var(--border); padding: 0.5rem 0.7rem; text-align: left; vertical-align: top; }
thead th { background: var(--bg); }

pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  overflow-x: auto;
  font-size: 0.9rem;
  line-height: 1.45;
}

.button {
  display: inline-block;
  background: var(--accent);
  color: var(--accent-text);
  border: 0;
  border-radius: var(--radius);
  padding: 0.6rem 1rem;
  font: inherit;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.95rem;
}
.site-footer .wrap { padding-block: 1.5rem; }

/* ---------- Demo page: "Riverside Library" ---------- */
/* Shared by exercises/broken.html and exercises/fixed.html */

.demo-banner {
  background: var(--warn-bg);
  border-bottom: 2px solid var(--warn-border);
  font-size: 0.95rem;
}
.demo-banner.good { background: var(--good-bg); border-color: var(--good-border); }
.demo-banner .wrap { padding-block: 0.6rem; display: flex; flex-wrap: wrap; gap: 0.5rem 1rem; align-items: center; justify-content: space-between; }

.lib-top { background: var(--brand); color: #fff; }
@media (prefers-color-scheme: dark) { .lib-top { color: #10140f; } }
.lib-top .wrap { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.75rem 2rem; padding-block: 1rem; }
.lib-logo { font-size: 1.35rem; font-weight: 800; letter-spacing: 0.01em; margin: 0; line-height: 1.2; }
.lib-logo a { color: inherit; text-decoration: none; }
.lib-menu { display: flex; flex-wrap: wrap; gap: 0.25rem 1.25rem; list-style: none; margin: 0; padding: 0; }
.lib-menu a { color: inherit; font-weight: 600; }

.lib-search { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.lib-search input {
  font: inherit;
  padding: 0.4rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  min-width: 0;
  flex: 1 1 10rem;
}
.lib-search button { font: inherit; padding: 0.4rem 0.8rem; border-radius: 6px; border: 1px solid #fff; background: transparent; color: inherit; cursor: pointer; }

.lib-crumbs { font-size: 0.9rem; color: var(--muted); margin: 1.25rem 0 0; }
.lib-crumbs ol { display: flex; flex-wrap: wrap; gap: 0.25rem; list-style: none; padding: 0; margin: 0; }
.lib-crumbs li + li::before { content: "›"; margin-right: 0.25rem; }

.lib-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
  padding-block: 1.25rem 3rem;
}
@media (min-width: 56rem) {
  .lib-layout { grid-template-columns: minmax(0, 1fr) 19rem; }
}

/* Visual "heading" styles — applied to real headings on the fixed page and
   to divs/spans on the broken page, so both look the same. */
.t-page { font-size: clamp(1.9rem, 4.5vw, 2.7rem); font-weight: 800; line-height: 1.15; margin: 0 0 0.75rem; }
.t-section { font-size: 1.5rem; font-weight: 700; line-height: 1.25; margin: 2.25rem 0 0.75rem; }
.t-sub { font-size: 1.15rem; font-weight: 700; line-height: 1.3; margin: 1.5rem 0 0.5rem; }
.t-side { font-size: 1.1rem; font-weight: 700; margin: 0 0 0.5rem; }
.t-foot { font-size: 1rem; font-weight: 700; margin: 0 0 0.5rem; }

.lib-meta { color: var(--muted); margin: 0 0 1.25rem; }

.lib-hero {
  aspect-ratio: 16 / 7;
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 20% 30%, #e9b949 0 9%, transparent 10%),
    radial-gradient(circle at 75% 60%, #c4572e 0 13%, transparent 14%),
    radial-gradient(circle at 45% 80%, #8c3b1f 0 7%, transparent 8%),
    linear-gradient(135deg, #f3d9a4, #d9874a);
  margin-bottom: 1.25rem;
}

.lib-events { list-style: none; padding: 0; margin: 0; display: grid; gap: 0.75rem; }
.lib-events li { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 0.9rem 1rem; }
.lib-events .when { display: block; font-size: 0.9rem; color: var(--muted); }

.lib-side-box { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem 1.1rem; margin-bottom: 1rem; }
.lib-side-box ul { margin: 0; padding-left: 1.1rem; }
.lib-hours { width: 100%; min-width: 0; border: 0; }
.lib-hours th, .lib-hours td { border: 0; border-bottom: 1px solid var(--border); padding: 0.3rem 0; }
.lib-hours td { text-align: right; }

.lib-newsletter { display: grid; gap: 0.5rem; }
.lib-newsletter input { font: inherit; padding: 0.45rem 0.6rem; border: 1px solid var(--border); border-radius: 6px; background: var(--bg); color: var(--text); }

.lib-footer { background: var(--surface); border-top: 1px solid var(--border); }
.lib-footer .wrap { display: grid; gap: 1.5rem; grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr)); padding-block: 2rem; }
.lib-footer ul { list-style: none; padding: 0; margin: 0; }
.lib-footer p { margin: 0; color: var(--muted); }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  margin: -1px; padding: 0; border: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}