:root {
  color-scheme: light dark;
  --paper: #f8efd9;
  --paper-strong: #fffaf0;
  --ink: #2b2418;
  --muted: #6f624e;
  --accent: #2f6f5b;
  --line: rgba(72, 56, 31, 0.16);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, #fff9ea, var(--paper) 55%, #e7d3a7);
  color: var(--ink);
  font: 16px/1.6 "Segoe UI", system-ui, sans-serif;
}

a { color: var(--accent); }

.public-shell { width: min(1040px, calc(100% - 32px)); margin: 0 auto; }

.public-header,
.public-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 22px 0;
}

.public-header nav { display: flex; flex-wrap: wrap; gap: 14px; }
.public-brand { color: var(--ink); font-size: 1.2rem; font-weight: 800; text-decoration: none; }

.public-main {
  padding: clamp(28px, 6vw, 72px) 0;
}

.public-hero,
.public-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: color-mix(in srgb, var(--paper-strong) 92%, transparent);
  box-shadow: 0 18px 55px rgba(63, 45, 17, 0.10);
}

.public-hero { padding: clamp(24px, 5vw, 54px); }
.public-eyebrow { color: var(--accent); font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
h1 { max-width: 22ch; margin: 8px 0 16px; font-size: clamp(2rem, 6vw, 4.4rem); line-height: 1.04; }
.public-lead { max-width: 70ch; color: var(--muted); font-size: 1.08rem; }
.public-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.public-button { display: inline-flex; min-height: 44px; align-items: center; padding: 8px 16px; border-radius: 10px; background: var(--accent); color: white; font-weight: 800; text-decoration: none; }
.public-button.secondary { border: 1px solid var(--line); background: transparent; color: var(--ink); }

.public-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(250px, 100%), 1fr)); gap: 18px; margin-top: 28px; }
.public-card { overflow: hidden; }
.public-card img,
.public-challenge-image { display: block; width: 100%; max-height: 520px; object-fit: cover; }
.public-card-body { padding: 20px; }
.public-card h2 { margin: 0 0 8px; line-height: 1.2; }
.public-card p { color: var(--muted); }
.public-meta { color: var(--muted); font-size: .92rem; }
.public-footer { margin-top: 30px; border-top: 1px solid var(--line); color: var(--muted); }

@media (prefers-color-scheme: dark) {
  :root { --paper: #171b18; --paper-strong: #202720; --ink: #f4ead2; --muted: #c2b69e; --accent: #8bd0b4; --line: rgba(244, 234, 210, .14); }
  body { background: radial-gradient(circle at top, #263229, var(--paper) 58%, #121411); }
  .public-button { color: #102019; }
}