/* Shared design system for the Compound Interest Calculator site
   Used by about.html, privacy-policy.html, and contact.html.
   (The calculator page keeps its own inline styles for the interactive UI.) */

:root {
  --bg: #f4f6f8;
  --surface: #ffffff;
  --surface-2: #f8fafb;
  --border: #e2e8ee;
  --text: #0f1b29;
  --text-soft: #51606f;
  --text-faint: #7d8a98;
  --accent: #0b5e55;
  --accent-strong: #094b44;
  --accent-soft: #e6f3f0;
  --shadow-sm: 0 1px 2px rgba(15, 27, 41, .06);
  --radius: 16px;
  --radius-sm: 10px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji";
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.wrap { width: 100%; max-width: 760px; margin: 0 auto; padding: 0 18px; }

/* ---------- Top nav header ---------- */
header.site-header {
  background: linear-gradient(160deg, #0b5e55 0%, #0a4a44 100%);
  color: #eafaf6;
}
header.site-header .bar {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 10px 18px; padding: 16px 0;
}
header.site-header .brand {
  display: inline-flex; align-items: center; gap: 9px;
  color: #fff; font-weight: 800; font-size: 1.05rem; text-decoration: none; letter-spacing: -.01em;
}
header.site-header .brand:hover { color: #fff; }
nav.top-nav { display: flex; flex-wrap: wrap; gap: 4px; }
nav.top-nav a {
  color: #c8e9e2; text-decoration: none; font-size: .9rem; font-weight: 600;
  padding: 6px 11px; border-radius: 999px; transition: background .15s, color .15s;
}
nav.top-nav a:hover { background: rgba(255,255,255,.12); color: #fff; }
nav.top-nav a[aria-current="page"] { background: rgba(255,255,255,.16); color: #fff; }

/* ---------- Page hero ---------- */
.page-hero { background: linear-gradient(160deg, #0b5e55 0%, #0a4a44 100%); color: #eafaf6; padding: 26px 0 36px; }
.page-hero h1 { margin: 0 0 8px; color: #fff; font-size: clamp(1.6rem, 4.5vw, 2.3rem); letter-spacing: -.02em; line-height: 1.15; }
.page-hero p { margin: 0; color: #c8e9e2; max-width: 60ch; }
.page-hero .updated { display: inline-block; margin-top: 12px; font-size: .82rem; color: #aedfd6; background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.16); padding: 4px 11px; border-radius: 999px; }

/* ---------- Content ---------- */
main { flex: 1 0 auto; padding: 28px 0 40px; }
.prose {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: 26px;
}
@media (min-width: 600px) { .prose { padding: 38px; } }
.prose h2 { font-size: clamp(1.2rem, 3vw, 1.45rem); letter-spacing: -.01em; margin: 30px 0 10px; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { font-size: 1.05rem; margin: 22px 0 6px; }
.prose p { color: var(--text-soft); margin: 0 0 14px; }
.prose ul { color: var(--text-soft); padding-left: 20px; margin: 0 0 14px; }
.prose li { margin-bottom: 8px; }
.prose strong { color: var(--text); }
.prose a { color: var(--accent); font-weight: 600; }
.prose a:hover { color: var(--accent-strong); }

.callout {
  background: var(--accent-soft); border: 1px solid #cfe7e1; border-radius: var(--radius-sm);
  padding: 16px 18px; margin: 0 0 20px;
}
.callout p { margin: 0; color: var(--accent-strong); }

.btn {
  display: inline-flex; align-items: center; gap: 8px; text-decoration: none;
  background: var(--accent); color: #fff; font-weight: 600; font-size: .95rem;
  padding: 12px 20px; border-radius: var(--radius-sm); transition: background .15s;
}
.btn:hover { background: var(--accent-strong); color: #fff; }

.email-link {
  display: inline-block; font-size: 1.15rem; font-weight: 700; color: var(--accent);
  text-decoration: none; word-break: break-all;
}
.email-link:hover { color: var(--accent-strong); text-decoration: underline; }

/* ---------- Footer with nav ---------- */
footer.site-footer {
  flex-shrink: 0; background: #0f1b29; color: #a9b6c4; padding: 32px 0 40px; margin-top: 10px;
}
footer.site-footer .wrap { max-width: 860px; }
nav.footer-nav { display: flex; flex-wrap: wrap; gap: 6px 8px; justify-content: center; margin-bottom: 18px; }
nav.footer-nav a {
  color: #d6e0ea; text-decoration: none; font-size: .9rem; font-weight: 600;
  padding: 7px 14px; border-radius: 999px; transition: background .15s, color .15s;
}
nav.footer-nav a:hover { background: rgba(255,255,255,.08); color: #fff; }
nav.footer-nav a[aria-current="page"] { background: rgba(255,255,255,.12); color: #fff; }
footer.site-footer .disclaimer { font-size: .8rem; line-height: 1.6; text-align: center; max-width: 70ch; margin: 0 auto 12px; color: #8b99a8; }
footer.site-footer .copyright { font-size: .8rem; text-align: center; margin: 0; color: #6f7d8c; }
footer.site-footer a.inline { color: #aedfd6; }

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