:root {
  --green: #3b7c4f;
  --green-dark: #2a5c39;
  --green-soft: #e8f2eb;
  --ink: #1a1a18;
  --ink-2: #4a4a44;
  --ink-3: #73736c;
  --paper: #fafaf8;
  --white: #ffffff;
  --line: #e8e5de;
  --shadow: 0 16px 42px rgba(38, 57, 42, 0.08);
  --radius: 16px;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
img { max-width: 100%; }

.public-nav {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 64px;
  padding: 10px clamp(18px, 5vw, 72px);
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
}
.public-brand {
  text-decoration: none;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.3px;
}
.public-brand span { color: var(--green); }
.public-nav-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 22px;
  flex-wrap: wrap;
}
.public-nav-links a {
  text-decoration: none;
  color: var(--ink-2);
  font-size: 14px;
  font-weight: 650;
}
.public-nav-links a:hover { color: var(--green-dark); }
.public-nav-links .nav-cta {
  color: #fff;
  background: var(--green);
  padding: 9px 15px;
  border-radius: 999px;
}
.public-nav-links .nav-cta:hover { color: #fff; background: var(--green-dark); }

.public-shell {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
  padding: 36px 0 80px;
}
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 30px;
  color: var(--ink-3);
  font-size: 13px;
}
.breadcrumbs a { text-decoration: none; }
.breadcrumbs a:hover { color: var(--green); }
.breadcrumbs span[aria-hidden="true"] { opacity: 0.5; }

.public-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(260px, 0.65fr);
  gap: 36px;
  align-items: end;
  padding: clamp(30px, 6vw, 68px);
  border: 1px solid var(--line);
  border-radius: 24px;
  background:
    radial-gradient(circle at 88% 10%, rgba(194, 222, 202, 0.72), transparent 34%),
    linear-gradient(135deg, #fff 0%, #f6fbf7 100%);
  box-shadow: var(--shadow);
}
.eyebrow {
  margin: 0 0 14px;
  color: var(--green);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}
.public-hero h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(38px, 6vw, 68px);
  line-height: 1.02;
  letter-spacing: -0.045em;
}
.public-hero p {
  margin: 20px 0 0;
  max-width: 730px;
  color: var(--ink-2);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.7;
}
.hero-actions { display: flex; gap: 10px; flex-wrap: wrap; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 18px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  color: var(--ink-2);
  text-decoration: none;
  font-size: 14px;
  font-weight: 750;
}
.button.primary { color: #fff; border-color: var(--green); background: var(--green); }
.button:hover { transform: translateY(-1px); }
.button.primary:hover { background: var(--green-dark); }

.section { padding-top: 56px; }
.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 22px;
}
.section h2 {
  margin: 0;
  font-size: clamp(27px, 4vw, 42px);
  line-height: 1.1;
  letter-spacing: -0.035em;
}
.section-sub {
  margin: 9px 0 0;
  max-width: 720px;
  color: var(--ink-3);
  font-size: 15px;
  line-height: 1.7;
}

.category-list {
  display: flex;
  gap: 9px;
  flex-wrap: wrap;
  margin: 28px 0 0;
}
.category-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  color: var(--ink-2);
  text-decoration: none;
  font-size: 13px;
  font-weight: 700;
}
.category-link.active,
.category-link:hover { border-color: #b9d8c1; background: var(--green-soft); color: var(--green-dark); }
.category-count {
  min-width: 22px;
  padding: 2px 7px;
  border-radius: 999px;
  background: rgba(59, 124, 79, 0.1);
  text-align: center;
  font-size: 11px;
}

.study-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}
.study-card {
  display: flex;
  min-width: 0;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--white);
  box-shadow: 0 7px 22px rgba(38, 57, 42, 0.04);
  text-decoration: none;
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 160ms ease;
}
.study-card:hover {
  transform: translateY(-3px);
  border-color: #b9d8c1;
  box-shadow: var(--shadow);
}
.study-body {
  display: flex;
  flex: 1;
  flex-direction: column;
  padding: 19px;
}
.study-kicker {
  margin-bottom: 8px;
  color: var(--green);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.study-title {
  margin: 0;
  font-size: 18px;
  line-height: 1.35;
  letter-spacing: -0.02em;
}
.study-summary {
  margin: 10px 0 18px;
  color: var(--ink-3);
  font-size: 14px;
  line-height: 1.62;
}
.study-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: auto;
}
.meta-pill {
  padding: 6px 9px;
  border-radius: 999px;
  background: #f3f3ef;
  color: var(--ink-2);
  font-size: 12px;
  font-weight: 700;
}
.meta-pill.reward { background: var(--green-soft); color: var(--green-dark); }

.empty-state {
  padding: 50px 24px;
  border: 1px dashed #cfcac0;
  border-radius: var(--radius);
  background: #fff;
  text-align: center;
}
.empty-state h2 { font-size: 24px; }
.empty-state p { max-width: 560px; margin: 10px auto 22px; color: var(--ink-3); line-height: 1.65; }

.content-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}
.content-card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}
.content-card .number {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  margin-bottom: 18px;
  border-radius: 50%;
  background: var(--green-soft);
  color: var(--green-dark);
  font-weight: 850;
}
.content-card h2,
.content-card h3 { margin: 0 0 10px; font-size: 20px; letter-spacing: -0.02em; }
.content-card p { margin: 0; color: var(--ink-3); line-height: 1.7; }

.prose {
  max-width: 840px;
  margin: 0 auto;
  padding: clamp(24px, 5vw, 56px);
  border: 1px solid var(--line);
  border-radius: 20px;
  background: #fff;
  box-shadow: var(--shadow);
}
.prose h1 { margin: 0 0 12px; font-size: clamp(36px, 6vw, 58px); letter-spacing: -0.045em; }
.prose .lead { margin: 0 0 34px; color: var(--ink-2); font-size: 18px; line-height: 1.7; }
.prose h2 { margin: 34px 0 10px; font-size: 24px; letter-spacing: -0.025em; }
.prose h3 { margin: 24px 0 8px; font-size: 18px; }
.prose p,
.prose li { color: var(--ink-2); line-height: 1.75; }
.prose ul { padding-left: 22px; }
.prose .updated { color: var(--ink-3); font-size: 13px; }
.prose a { color: var(--green-dark); }

.public-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  flex-wrap: wrap;
  padding: 28px clamp(18px, 5vw, 72px);
  border-top: 1px solid var(--line);
  background: #fff;
  color: var(--ink-3);
  font-size: 13px;
}
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer-links a { text-decoration: none; }
.footer-links a:hover { color: var(--green-dark); }

@media (max-width: 900px) {
  .public-hero { grid-template-columns: 1fr; align-items: start; }
  .study-grid, .content-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .public-nav { align-items: flex-start; }
  .public-nav-links { gap: 12px; }
  .public-nav-links a:not(.nav-cta) { display: none; }
  .public-shell { width: min(100% - 24px, 1120px); padding-top: 22px; }
  .public-hero { padding: 28px 22px; border-radius: 18px; }
  .study-grid, .content-grid { grid-template-columns: 1fr; }
  .section { padding-top: 42px; }
  .section-head { align-items: flex-start; flex-direction: column; }
}