:root {
  --bg: #faf8f3;
  --surface: #ffffff;
  --ink: #1d232b;
  --muted: #5b6470;
  --rule: #e3dfd5;
  --accent: #0f6b5e;
  --dot: #c2562f;
  --bar: #cfdcd7;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14181d;
    --surface: #1b2027;
    --ink: #e7e9ec;
    --muted: #9aa3ad;
    --rule: #2b323b;
    --accent: #5cc2b0;
    --dot: #e98a62;
    --bar: #2f403c;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 var(--sans);
}
.wrap { max-width: 760px; margin: 0 auto; padding: 56px 20px 80px; }

h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.2; }
h1 { font-size: clamp(2.2rem, 7vw, 3.4rem); margin: 0; letter-spacing: -0.01em; }
h2 { font-size: 1.6rem; margin: 64px 0 20px; padding-top: 24px; border-top: 1px solid var(--rule); }
h3 { font-size: 1.15rem; margin: 0 0 4px; }
p { margin: 0 0 12px; }
.tagline { font-family: var(--serif); font-size: 1.35rem; color: var(--accent); margin: 8px 0 20px; }
.lede { font-size: 1.1rem; max-width: 36em; }
.muted { color: var(--muted); }

/* the simulation on the home page */
.sim { margin: 40px 0 0; padding: 20px 20px 16px; background: var(--surface); border: 1px solid var(--rule); border-radius: 10px; }
.sim svg { display: block; width: 100%; height: auto; }
.panel-label { font-size: 0.92rem; font-weight: 600; margin: 0 0 4px; }
.panel + .panel { margin-top: 12px; }
.pop rect { fill: var(--bar); }
.pile circle { fill: var(--dot); }
.sim .mean { stroke: var(--ink); stroke-width: 1.5; stroke-dasharray: 5 4; }
.sim .axis { stroke: var(--muted); stroke-width: 1; }
.sim .rug { stroke: var(--dot); stroke-width: 2; }
.sim .falling { animation: drop 0.35s ease-out both; transform-box: fill-box; }
@keyframes drop { from { transform: translateY(-28px); opacity: 0; } to { transform: none; opacity: 1; } }
.sim figcaption { display: flex; gap: 16px; align-items: flex-start; justify-content: space-between; margin-top: 12px; font-size: 0.95rem; color: var(--muted); }
.again {
  flex: none; font: inherit; font-weight: 600; color: var(--accent);
  background: none; border: 1.5px solid var(--accent); border-radius: 999px; padding: 4px 14px; cursor: pointer;
}
.again:hover { background: var(--accent); color: var(--bg); }
.again:focus-visible { outline: 3px solid var(--dot); outline-offset: 2px; }

.ways { display: grid; grid-template-columns: 1fr 1fr; gap: 24px 32px; }
.ways p { color: var(--muted); }

.path { list-style: none; counter-reset: step; margin: 0; padding: 0; }
.path li { counter-increment: step; position: relative; padding: 0 0 20px 52px; }
.path li::before {
  content: counter(step); position: absolute; left: 0; top: -2px;
  width: 34px; height: 34px; border-radius: 50%; border: 1.5px solid var(--accent);
  color: var(--accent); font: 600 1rem/31px var(--serif); text-align: center;
}
.path p { color: var(--muted); }
.term { font-family: var(--sans); font-size: 0.85rem; font-weight: 500; color: var(--muted); margin-left: 8px; }
.note { margin-top: 12px; font-style: italic; color: var(--muted); }

@media (max-width: 600px) {
  body { font-size: 16px; }
  .wrap { padding: 36px 16px 56px; }
  .sim { padding: 14px 12px 12px; }
  .sim figcaption { flex-direction: column; }
  .ways { grid-template-columns: 1fr; }
  .term { display: block; margin: 2px 0 0; }
}
@media (prefers-reduced-motion: reduce) {
  .sim .falling { animation: none; }
}