/* One accent colour (teal). All text colours pass WCAG AA on their backgrounds. */
:root {
  color-scheme: light;
  --ink: #1a1f24;        /* body text, 15.9:1 on white */
  --muted: #4a5560;      /* secondary text, 7.4:1 on white */
  --accent: #0d6b5e;     /* links and highlights, 6.5:1 on white */
  --accent-dark: #094d44;
  --accent-tint: #e8f3f1;
  --line: #d9dee2;
  --bg: #ffffff;
  --bg-alt: #f6f8f9;
  --max: 68rem;
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.6;
}

a { color: var(--accent); text-underline-offset: 0.2em; }
a:hover { color: var(--accent-dark); }
a:focus-visible,
.button:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

h1, h2, h3 { line-height: 1.2; margin: 0 0 0.75rem; }
h1 { font-size: clamp(1.75rem, 5vw + 0.5rem, 2.75rem); letter-spacing: -0.01em; }
h2 { font-size: clamp(1.4rem, 2vw + 0.8rem, 1.9rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1rem; }

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 1rem;
  z-index: 10;
}
.skip-link:focus { top: 1rem; color: #fff; }

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

section { padding: 3rem 0; }
section:nth-of-type(even) { background: var(--bg-alt); }

.eyebrow {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.lead { font-size: 1.15rem; color: var(--muted); max-width: 46rem; }

/* Hero */
.hero { padding: 3.5rem 0 3rem; border-top: 6px solid var(--accent); }
.hero h1 { max-width: 48rem; }

.links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  list-style: none;
  padding: 0;
  margin: 1.5rem 0 0;
}

.button {
  display: inline-block;
  padding: 0.65rem 1.1rem;
  border: 2px solid var(--accent);
  border-radius: 6px;
  font-weight: 600;
  text-decoration: none;
}
.button.primary { background: var(--accent); color: #fff; }
.button.primary:hover { background: var(--accent-dark); border-color: var(--accent-dark); color: #fff; }
.button:hover { background: var(--accent-tint); }

/* Evidence table: stacked cards on small screens, a table from 48rem */
.evidence { width: 100%; border-collapse: collapse; margin-top: 1.5rem; }
.evidence caption { text-align: left; color: var(--muted); margin-bottom: 0.75rem; }
.evidence thead { display: none; }
.evidence tr {
  display: block;
  background: var(--bg);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: 6px;
  padding: 1rem;
  margin-bottom: 1rem;
}
.evidence th,
.evidence td { display: block; text-align: left; vertical-align: top; }
.evidence th[scope="row"] { font-size: 1.05rem; margin-bottom: 0.5rem; }
.evidence td { padding: 0.25rem 0; }
.evidence td::before {
  content: attr(data-label);
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}
.evidence td.result { font-weight: 600; color: var(--accent-dark); }

@media (min-width: 48rem) {
  .evidence thead { display: table-header-group; }
  .evidence tr { display: table-row; border: 0; padding: 0; margin: 0; background: none; }
  .evidence th,
  .evidence td { display: table-cell; padding: 0.9rem 0.75rem; border-bottom: 1px solid var(--line); }
  .evidence thead th {
    background: var(--accent);
    color: #fff;
    font-size: 0.95rem;
  }
  .evidence tbody tr:nth-child(odd) { background: var(--bg); }
  .evidence th[scope="row"] { width: 24%; font-size: 1rem; margin: 0; }
  .evidence td.result { width: 28%; }
  .evidence td::before { content: none; }
}

/* Case studies */
.cases { display: grid; gap: 1.25rem; margin-top: 1.5rem; }
.case {
  background: var(--bg);
  border: 1px solid var(--line);
  border-top: 4px solid var(--accent);
  border-radius: 6px;
  padding: 1.25rem;
}
.case dl { margin: 0; }
.case dt { font-weight: 700; color: var(--accent-dark); margin-top: 0.75rem; }
.case dd { margin: 0.15rem 0 0; }

@media (min-width: 60rem) {
  .cases { grid-template-columns: repeat(3, 1fr); }
}

/* Lists */
.plan { padding-left: 1.25rem; max-width: 50rem; }
.plan li { margin-bottom: 0.6rem; }
.plan strong { color: var(--accent-dark); }

footer {
  padding: 2rem 0;
  color: var(--muted);
  font-size: 0.95rem;
  border-top: 1px solid var(--line);
}

/* Root intro page */
.intro {
  min-height: 100vh;
  display: flex;
  align-items: center;
  border-top: 6px solid var(--accent);
}
.intro .wrap { padding-top: 3rem; padding-bottom: 3rem; }