/* BehaviorTrail website. Colors follow Docs/Design-Guide.md. */
:root {
  --bg: #ffffff;
  --bg-soft: #f3f8f8;
  --card: #ffffff;
  --text: #1c2526;
  --muted: #56666a;
  --line: #dde8e9;
  --accent: #1F6F78;        /* text-safe teal, light */
  --brand: #2A8C96;         /* icon teal, decorative */
  --mist: #B9DFE3;
  --coral: #E0745A;         /* decorative only */
  --win: #2E7D4F;
  --celebrate: #B7860B;
  --attention: #B35A07;
  --on-accent: #ffffff;
  --radius: 18px;
  --max: 1080px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1415;
    --bg-soft: #162021;
    --card: #1a2526;
    --text: #e8eff0;
    --muted: #a3b3b6;
    --line: #2a3a3c;
    --accent: #5CC0C9;
    --win: #4cc777;
    --celebrate: #f2c94c;
    --attention: #ff9f45;
    --on-accent: #0b1a1c;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-underline-offset: 3px; }
img { max-width: 100%; display: block; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 16px; top: 12px; background: var(--card); padding: 8px 12px; border-radius: 8px; z-index: 10; }

/* Header */
.site-header { border-bottom: 1px solid var(--line); background: var(--bg); position: sticky; top: 0; z-index: 5; }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; color: var(--text); text-decoration: none; }
.brand img { width: 32px; height: 32px; border-radius: 8px; }
.site-nav { display: flex; gap: 20px; font-size: 15px; }
.site-nav a { color: var(--muted); text-decoration: none; }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--accent); }

/* Hero */
.hero { background: linear-gradient(180deg, var(--bg-soft), var(--bg)); padding: 72px 0 56px; }
.hero .wrap { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 48px; align-items: center; }
.eyebrow { color: var(--accent); font-weight: 600; font-size: 15px; letter-spacing: 0.02em; margin: 0 0 12px; }
h1 { font-size: clamp(36px, 6vw, 56px); line-height: 1.08; letter-spacing: -0.02em; margin: 0 0 20px; }
.lead { font-size: 20px; color: var(--muted); margin: 0 0 28px; max-width: 34em; }
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.button {
  display: inline-flex; align-items: center; justify-content: center; min-height: 48px;
  padding: 0 22px; border-radius: 999px; background: var(--accent); color: var(--on-accent);
  font-weight: 600; text-decoration: none;
}
.button.secondary { background: transparent; color: var(--accent); border: 1.5px solid var(--line); }
.note { font-size: 14px; color: var(--muted); }
.hero-art { display: flex; justify-content: center; }
.hero-art img { width: min(280px, 70vw); border-radius: 22%; box-shadow: 0 24px 60px rgba(31, 111, 120, 0.25); }

/* Sections */
section { padding: 64px 0; scroll-margin-top: 64px; }
section.soft { background: var(--bg-soft); }
h2 { font-size: clamp(26px, 4vw, 36px); line-height: 1.15; letter-spacing: -0.01em; margin: 0 0 12px; }
.section-lead { color: var(--muted); font-size: 18px; max-width: 40em; margin: 0 0 36px; }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.card h3 { margin: 12px 0 8px; font-size: 19px; }
.card p, .card ul { margin: 0; color: var(--muted); }
.card ul { padding-left: 20px; }
.card li + li { margin-top: 4px; }
.icon { width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center; background: var(--bg-soft); }
.icon svg { width: 24px; height: 24px; stroke: var(--accent); fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.icon.win svg { stroke: var(--win); }
.icon.celebrate svg { stroke: var(--celebrate); }

/* Loop */
.loop { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; counter-reset: step; padding: 0; margin: 0; list-style: none; }
.loop li { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; counter-increment: step; }
.loop li::before { content: counter(step); display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; background: var(--accent); color: var(--on-accent); font-weight: 700; font-size: 15px; margin-bottom: 10px; }
.loop strong { display: block; margin-bottom: 4px; }
.loop span { color: var(--muted); font-size: 16px; }

/* Trust */
.trust { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px 40px; padding: 0; margin: 0; list-style: none; }
.trust li { padding-left: 32px; position: relative; }
.trust li::before { content: ""; position: absolute; left: 0; top: 6px; width: 18px; height: 18px; border-radius: 50%; background: var(--win); -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 2a10 10 0 100 20 10 10 0 000-20zm-1.2 14.2l-4-4 1.4-1.4 2.6 2.6 5.6-5.6 1.4 1.4-7 7z'/%3E%3C/svg%3E") center/contain no-repeat; mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 2a10 10 0 100 20 10 10 0 000-20zm-1.2 14.2l-4-4 1.4-1.4 2.6 2.6 5.6-5.6 1.4 1.4-7 7z'/%3E%3C/svg%3E") center/contain no-repeat; }
.trust strong { display: block; }
.trust span { color: var(--muted); }

.disclaimer { border-left: 4px solid var(--mist); padding: 4px 0 4px 18px; color: var(--muted); max-width: 46em; }

/* Long-form pages (privacy, support) */
.page { padding: 48px 0 72px; }
.page .wrap { max-width: 760px; }
.page h1 { font-size: clamp(32px, 5vw, 44px); }
.page h2 { font-size: 24px; margin-top: 40px; }
.page h3 { font-size: 19px; margin: 24px 0 6px; }
.page p, .page li { color: var(--text); }
.page ul { padding-left: 22px; }
.page li + li { margin-top: 6px; }
.meta { color: var(--muted); font-size: 15px; }
.callout { background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; margin: 24px 0; }
.callout.danger { border-color: #d64545; }
details { border-bottom: 1px solid var(--line); padding: 14px 0; }
details summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; color: var(--accent); font-weight: 400; font-size: 22px; line-height: 1; }
details[open] summary::after { content: "–"; }
details p, details ol, details ul { color: var(--muted); margin: 10px 0 0; }

/* Footer */
.site-footer { border-top: 1px solid var(--line); padding: 32px 0 48px; font-size: 15px; color: var(--muted); }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px; }
.site-footer nav { display: flex; gap: 20px; }
.site-footer a { color: var(--muted); }

@media (max-width: 860px) {
  .hero .wrap { grid-template-columns: 1fr; gap: 32px; }
  .hero-art { order: -1; justify-content: flex-start; }
  .hero-art img { width: 120px; }
  .grid { grid-template-columns: 1fr; }
  .loop { grid-template-columns: 1fr 1fr; }
  .trust { grid-template-columns: 1fr; }
}
@media (max-width: 520px) {
  .site-nav { gap: 16px; }
  .site-nav .wide-only { display: none; }
  .brand { font-size: 17px; }
  .loop { grid-template-columns: 1fr; }
  .hero { padding-top: 40px; }
}