:root {
  --bg: #F4F2EB;
  --ink: #29383C;
  --paper: #FFFEFA;
  --accent: #B4634A;
  --secondary: #668A83;
  --result: #263B42;
  --border: #D7D5CB;
  --muted: #74807D;
  --formula: #E8DEBF;
  --max: 1260px;
  --serif: Georgia, "Times New Roman", serif;
  --sans: "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: "Cascadia Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.55;
  background-image:
    repeating-linear-gradient(90deg, transparent, transparent 47px, rgba(41, 56, 60, 0.035) 47px, rgba(41, 56, 60, 0.035) 48px),
    repeating-linear-gradient(0deg, transparent, transparent 23px, rgba(102, 138, 131, 0.04) 23px, rgba(102, 138, 131, 0.04) 24px);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(90deg, rgba(180, 99, 74, 0.06) 0 8px, transparent 8px),
    linear-gradient(0deg, transparent calc(100% - 8px), rgba(180, 99, 74, 0.05) calc(100% - 8px));
  opacity: 0.7;
}

img, svg { max-width: 100%; height: auto; }
a { color: var(--accent); }
a:hover { color: var(--ink); }

.wrap {
  width: min(100% - 32px, var(--max));
  margin-inline: auto;
}

.masthead {
  height: 68px;
  border-bottom: 1px solid var(--border);
  background: rgba(255, 254, 250, 0.92);
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: stretch;
}

.masthead-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: min(100% - 32px, var(--max));
  margin-inline: auto;
}

.wordmark {
  text-decoration: none;
  color: var(--ink);
  font-family: var(--sans);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 12px;
  line-height: 1.15;
  font-weight: 700;
  border-left: 2px solid var(--accent);
  padding-left: 10px;
}

.site-nav {
  display: flex;
  gap: 0;
  align-items: center;
}

.site-nav a {
  color: var(--ink);
  text-decoration: none;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 8px 10px;
  border-left: 1px solid var(--border);
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--accent);
}

.nav-toggle {
  display: none;
  background: var(--paper);
  border: 1px solid var(--border);
  color: var(--ink);
  height: 40px;
  padding: 0 12px;
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.section { padding: 48px 0; }
.section-label {
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 8px;
}
h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.2;
  margin: 0 0 12px;
}
h1 { font-size: clamp(32px, 4vw, 48px); }
h2 { font-size: clamp(24px, 3vw, 32px); }
h3 { font-size: 20px; }
.lede { max-width: 62ch; color: var(--ink); }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.mono, .num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
}
.kicker {
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.paper {
  background: var(--paper);
  border: 1px solid var(--border);
}

.btn {
  appearance: none;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 12px 14px;
  cursor: pointer;
  min-height: 44px;
}
.btn.ghost {
  background: transparent;
  color: var(--ink);
}
.btn.tiny {
  min-height: 36px;
  padding: 8px 10px;
  font-size: 11px;
}
.btn:hover { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.ghost:hover { color: #fff; }
.btn:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.chip {
  appearance: none;
  border: 1px solid var(--border);
  background: var(--paper);
  color: var(--ink);
  font-size: 13px;
  padding: 8px 10px;
  cursor: pointer;
  min-height: 40px;
}
.chip:hover { border-color: var(--accent); color: var(--accent); }

.field { display: flex; flex-direction: column; gap: 6px; }
.field label {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}
input[type="text"],
input[type="number"],
select {
  font-family: var(--mono);
  font-size: 18px;
  padding: 12px 12px;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--ink);
  min-height: 48px;
  width: 100%;
}

.error {
  color: var(--accent);
  min-height: 1.4em;
  font-size: 14px;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.footer {
  border-top: 1px solid var(--border);
  padding: 28px 0 48px;
  font-size: 14px;
}
.footer-id {
  font-family: var(--serif);
  font-size: 18px;
  margin: 0 0 12px;
}
.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
}
.footer-nav a {
  color: var(--ink);
  text-decoration: none;
  font-size: 13px;
}
.footer-nav a:hover { color: var(--accent); }

.article-wrap { width: min(100% - 32px, 760px); margin-inline: auto; padding: 40px 0 72px; }
.article-wrap p { max-width: 68ch; }
.faq { border-top: 1px solid var(--border); padding-top: 8px; }
.faq h3 { margin-top: 20px; }

.page-head { padding: 36px 0 8px; }

@media (max-width: 760px) {
  .masthead { height: auto; min-height: 68px; }
  .masthead-inner { padding: 10px 0; flex-wrap: wrap; }
  .nav-toggle { display: inline-flex; align-items: center; }
  .site-nav {
    display: none;
    flex-direction: column;
    width: 100%;
    border-top: 1px solid var(--border);
  }
  .site-nav.is-open { display: flex; }
  .site-nav a { border-left: 0; border-bottom: 1px solid var(--border); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}