:root {
  --paper: #f4efe6;
  --ink: #1c1917;
  --muted: #57534e;
  --line: #d6d0c4;
  --accent: #9a3412;
  --ok: #3f6212;
  --nav: #1c1917;
  --nav-text: #f4efe6;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Segoe UI", system-ui, sans-serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.55;
  font-size: 17px;
}

.top {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--nav);
  color: var(--nav-text);
}
.top-inner {
  max-width: 820px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  align-items: center;
  justify-content: space-between;
}
.brand {
  color: var(--nav-text);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.04em;
  display: flex;
  align-items: center;
  gap: 10px;
}
.logo-word { height: 28px; width: auto; display: block; }
.brand span { font-weight: 400; opacity: 0.75; font-size: 13px; }
nav { display: flex; flex-wrap: wrap; gap: 8px 14px; }
nav a {
  color: var(--nav-text);
  text-decoration: none;
  font-size: 13px;
  opacity: 0.85;
}
nav a:hover { opacity: 1; text-decoration: underline; }

.hero, main, footer {
  max-width: 820px;
  margin: 0 auto;
  padding: 0 20px;
}
.hero { padding-top: 36px; padding-bottom: 12px; }
.kicker {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 12px;
  color: var(--accent);
  margin: 0 0 8px;
}
h1 { font-size: 2rem; line-height: 1.15; margin: 0 0 12px; }
h2 { font-size: 1.35rem; margin: 2.2rem 0 0.7rem; }
h3 { font-size: 1.05rem; margin: 1.4rem 0 0.4rem; }
.lede { font-size: 1.12rem; color: var(--muted); }
.callout {
  background: #fff;
  border-left: 3px solid var(--accent);
  padding: 12px 14px;
  margin: 1.2rem 0;
}
.callout.ok { border-left-color: var(--ok); }
.hint {
  color: var(--muted);
  font-size: 0.95rem;
  margin: 0.35rem 0 0.9rem;
}

section { padding-bottom: 8px; border-bottom: 1px solid var(--line); }
section:last-of-type { border-bottom: 0; }

a { color: var(--accent); }
code {
  font-size: 0.9em;
  background: #fff;
  padding: 1px 5px;
}

figure { margin: 1.2rem 0; }
figure img {
  width: 100%;
  height: auto;
  display: block;
  background: #fff;
  border: 1px solid var(--line);
}
figure.concept img { background: #ece8e0; }
figcaption {
  font-size: 0.88rem;
  color: var(--muted);
  margin-top: 8px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  background: #fff;
}
th, td {
  border: 1px solid var(--line);
  padding: 8px 10px;
  text-align: left;
  vertical-align: top;
}
th { background: #ebe4d8; }

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 1.2rem 0;
}
.grid-3 figure { margin: 0; }

.checklist { list-style: none; padding: 0; }
.checklist li {
  padding: 6px 0 6px 28px;
  position: relative;
}
.checklist li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 14px;
  height: 14px;
  border: 2px solid var(--ink);
}

footer {
  background: #000;
  color: #a8a29e;
  padding: 0;
  font-size: 0.9rem;
  max-width: none;
}
.footer-inner {
  max-width: 820px;
  margin: 0 auto;
  padding: 28px 20px 48px;
}
.footer-logo {
  height: 32px;
  width: auto;
  display: block;
  margin-bottom: 12px;
}

.pdf-link { font-size: 0.95rem; }
.pdf-link a { font-weight: 600; }

@media (max-width: 700px) {
  body { font-size: 16px; }
  h1 { font-size: 1.65rem; }
  .logo-word { height: 24px; }
  nav { width: 100%; gap: 6px 12px; }
  nav a { font-size: 12px; }
  .grid-3 { grid-template-columns: 1fr; }
}

@media print {
  .top { position: static; }
  nav { display: none; }
  a { color: inherit; }
}