/* Pulse Instinct — landing page
   Design basis: themefisher "Small Apps" (MIT) hero/feature rhythm, re-skinned to
   Pulse Instinct's own tokens (pale blue #d5ddea, navy #022556, purple #8077ff, teal #16c1c9).
   No external CDN: fonts and images are served locally. */

@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("../assets/fonts/poppins-400.woff2") format("woff2");
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url("../assets/fonts/poppins-500.woff2") format("woff2");
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url("../assets/fonts/poppins-600.woff2") format("woff2");
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url("../assets/fonts/poppins-700.woff2") format("woff2");
}

:root {
  --navy: #022556;
  --navy-deep: #01163a;
  --pale: #d5ddea;
  --pale-soft: #eef2f8;
  --purple: #6257e8;   /* 5.19:1 with white, and as text on white */
  --teal: #16c1c9;
  --ink: #022556;
  --muted: #4f5f79;   /* 6.5:1 on white, 5.8:1 on the pale panels */
  --white: #ffffff;
  --radius: 18px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.16);
  --maxw: 1160px;
  --pad: clamp(20px, 5vw, 56px);
}

* { box-sizing: border-box; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Poppins", "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--ink);
  background: var(--white);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: inherit; }

.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
  padding: 0 var(--pad);
}

/* ---------- nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(2, 37, 86, 0.08);
  padding-bottom: 6px;
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: clamp(14px, 3vw, 34px);
  min-height: 72px;
  padding-top: 12px;
  padding-bottom: 12px;
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; margin-right: auto; }
.brand img { width: 34px; height: 34px; border-radius: 9px; }
.brand span { font-weight: 700; letter-spacing: 0.14em; font-size: 14px; color: var(--navy); }
.nav-links { display: flex; gap: clamp(12px, 2.4vw, 26px); }
.nav-links a {
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  color: var(--navy);
  opacity: 0.82;
}
.nav-links a:hover { opacity: 1; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--purple); color: #fff; box-shadow: 0 10px 26px rgba(0, 0, 0, 0.32); }
.btn-ghost { background: transparent; color: var(--navy); border-color: rgba(2, 37, 86, 0.22); }
.btn-light { background: #fff; color: var(--navy); }
.btn-sm { padding: 10px 20px; font-size: 14px; }

/* ---------- hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, #022556 0%, #01163a 100%);
  color: #fff;
  padding: clamp(56px, 9vw, 104px) 0 clamp(64px, 9vw, 116px);
}
.hero-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 15px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  background: rgba(255, 255, 255, 0.08);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  margin-bottom: 22px;
}
.eyebrow i { width: 7px; height: 7px; border-radius: 50%; background: var(--teal); }
.hero h1 {
  font-size: clamp(30px, 4.6vw, 52px);
  line-height: 1.12;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 20px;
}
.hero h1 em { font-style: normal; color: #cfcaff; }
.hero p.lede {
  font-size: clamp(16px, 1.7vw, 19px);
  color: rgba(255, 255, 255, 0.82);
  max-width: 52ch;
  margin: 0 0 30px;
}
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 26px; }
.hero-note { font-size: 13px; color: rgba(255, 255, 255, 0.84); }
.hero-shot {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}
/* the asset is a cut-out device render with transparency: it sits directly on the
   hero gradient, sized by height so the composition stays tight at every width */
.hero-shot img {
  height: clamp(340px, 56vh, 560px);
  width: auto;
  max-width: 100%;
  filter: drop-shadow(0 18px 28px rgba(0, 0, 0, 0.5));
}

/* ---------- steps ---------- */
.steps {
  background: var(--pale-soft);
  padding: 40px 20px;
  padding: clamp(40px, 6vw, 72px) clamp(20px, 5vw, 56px);
}
/* the section now owns the horizontal inset, so the inner wrapper drops its own */
.steps > .wrap,
.science > .wrap {
  padding-left: 0;
  padding-right: 0;
}
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}
.step {
  background: #fff;
  border-radius: var(--radius);
  padding: 26px 24px;
  box-shadow: var(--shadow);
}
.step b { display: block; font-size: 13px; letter-spacing: 0.14em; color: var(--purple); margin-bottom: 10px; }
.step h3 { margin: 0 0 8px; font-size: 21px; font-weight: 600; }
.step p { margin: 0; color: var(--muted); font-size: 15px; max-width: 42ch; }

/* ---------- sections ---------- */
.section { padding: clamp(56px, 8vw, 104px) 0; }
.section-head { max-width: 62ch; margin: 0 0 clamp(30px, 4vw, 52px); }
.section-head p { max-width: 52ch; }
.section-head h2 { font-size: clamp(25px, 3.2vw, 38px); line-height: 1.2; margin: 0 0 14px; font-weight: 700; }
.section-head p { margin: 0; color: var(--muted); }

.row-split {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: clamp(26px, 5vw, 60px);
  align-items: center;
}
.row-split + .row-split { margin-top: clamp(48px, 7vw, 92px); }
.shot {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid rgba(2, 37, 86, 0.08);
  background: var(--pale-soft);
}
.shot img { width: 100%; object-position: top; }
.shot.dark { background: linear-gradient(150deg, #16213c 0%, #0a1120 55%, #060a13 100%); }
.copy h3 { font-size: clamp(21px, 2.4vw, 28px); margin: 0 0 14px; font-weight: 600; }
.copy p { margin: 0 0 14px; color: var(--muted); max-width: 54ch; }
.copy ul { margin: 0; padding-left: 20px; color: var(--muted); }
.copy li { margin-bottom: 8px; }

.device-panel {
  background: linear-gradient(160deg, #eef2f8 0%, #dde5f2 100%);
  border: 1px solid rgba(2, 37, 86, 0.1);
  border-radius: var(--radius);
  padding: clamp(22px, 4vw, 46px);
  display: flex;
  justify-content: center;
  align-items: center;
  box-shadow: var(--shadow);
}
.device-panel img {
  width: min(262px, 68%);
  border-radius: 14px;
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.22);
}

/* ---------- science band ---------- */
.science {
  background: #022556;
  color: #fff;
  padding: 56px 20px;
  padding: clamp(56px, 8vw, 100px) clamp(20px, 5vw, 56px);
}
.science .section-head p { color: rgba(255, 255, 255, 0.78); }
.science-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: clamp(26px, 5vw, 56px);
  align-items: center;
}
.science-shot { border-radius: var(--radius); overflow: hidden; box-shadow: 0 30px 70px rgba(0, 0, 0, 0.4); }
.science-shot img { width: 100%; object-position: top; }
.science-facts { display: grid; gap: 18px; }
.fact { position: relative; padding-left: 22px; }
.fact::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--teal);
}
.fact b { display: block; font-size: 17px; font-weight: 600; margin-bottom: 4px; }
.fact span { color: rgba(255, 255, 255, 0.8); font-size: 15px; max-width: 52ch; display: block; }

/* ---------- faq ---------- */
.faq { display: grid; gap: 14px; }
details {
  border: 1px solid rgba(2, 37, 86, 0.18);
  border-radius: 14px;
  padding: 18px 22px;
  background: #fff;
}
details[open] { box-shadow: var(--shadow); }
summary { cursor: pointer; font-weight: 600; font-size: 17px; }
details p { margin: 12px 0 0; color: var(--muted); max-width: 56ch; }

/* ---------- cta ---------- */
.cta {
  background: linear-gradient(150deg, var(--purple), #5b52d6);
  color: #fff;
  border-radius: 26px;
  padding: clamp(34px, 6vw, 64px);
  text-align: center;
  margin: 0 0 clamp(56px, 8vw, 96px);
}
.cta h2 { font-size: clamp(24px, 3.4vw, 38px); margin: 0 0 12px; font-weight: 700; }
.cta p { margin: 0 auto 26px; max-width: 46ch; color: rgba(255, 255, 255, 0.92); }

/* ---------- footer ---------- */
.footer {
  background: #01163a;
  color: rgba(255, 255, 255, 0.8);
  padding: clamp(44px, 6vw, 72px) 0 32px;
  font-size: 14px;
}
.footer-top {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: clamp(24px, 4vw, 46px);
  padding-bottom: clamp(28px, 4vw, 44px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}
.footer-brand { grid-column: span 1; }
.footer-brand .brand span { color: #fff; }
.footer-brand p { margin: 14px 0 0; max-width: 34ch; line-height: 1.6; color: rgba(255, 255, 255, 0.8); }
.footer-cn { color: rgba(255, 255, 255, 0.68) !important; font-size: 13px; }
.footer-col h3 {
  margin: 0 0 14px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.94);
}
.footer-col a { display: block; margin-bottom: 10px; }
.footer a { color: rgba(255, 255, 255, 0.8); text-decoration: none; }
.footer a:hover { color: #fff; text-decoration: underline; }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  align-items: center;
  justify-content: space-between;
  padding-top: 22px;
  color: rgba(255, 255, 255, 0.72);
  font-size: 13px;
}

@media (max-width: 640px) {
  .nav-links { display: none; }
  body { font-size: 16px; }
}