/* Battery Intelligence — site styles */
:root {
  --navy-0: #0a1230;
  --navy-1: #0f1b46;
  --navy-2: #16224f;
  --navy-3: #1e2f66;
  --line: #2b3c78;
  --text: #eef2ff;
  --text-muted: #a9b8e6;
  --text-dim: #7d8dc4;
  --green: #34d17d;
  --green-bright: #5eea8d;
  --blue: #4f9bff;
  --radius: 14px;
  --maxw: 1080px;
  --font: -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--navy-0);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--green-bright); text-decoration: none; }
a:hover { text-decoration: underline; }

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

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(10, 18, 48, 0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 62px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 650; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand img { width: 30px; height: 30px; }
.nav-links { display: flex; align-items: center; gap: 22px; font-size: 0.94rem; }
.nav-links a { color: var(--text-muted); }
.nav-links a:hover { color: var(--text); text-decoration: none; }
.nav-cta {
  background: var(--green);
  color: #06231a !important;
  padding: 8px 16px;
  border-radius: 9px;
  font-weight: 650;
}
.nav-cta:hover { background: var(--green-bright); text-decoration: none; }

/* ---------- hero ---------- */
.hero {
  background:
    radial-gradient(1200px 500px at 70% -10%, rgba(79, 155, 255, 0.16), transparent 60%),
    linear-gradient(180deg, var(--navy-1), var(--navy-0));
  border-bottom: 1px solid var(--line);
  padding: 84px 0 72px;
  text-align: center;
}
.hero img.app-icon { width: 108px; height: 108px; margin: 0 auto 26px; }
.hero h1 {
  font-size: clamp(2.1rem, 5vw, 3.2rem);
  line-height: 1.12;
  margin: 0 0 18px;
  letter-spacing: -0.02em;
}
.hero p.lede {
  font-size: clamp(1.05rem, 2.4vw, 1.3rem);
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto 34px;
}
.cta-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 14px 26px;
  border-radius: 11px;
  font-weight: 650;
  font-size: 1.02rem;
  border: 1px solid transparent;
  cursor: pointer;
}
.btn-primary { background: var(--green); color: #06231a; }
.btn-primary:hover { background: var(--green-bright); text-decoration: none; }
.btn-ghost { border-color: var(--line); color: var(--text); background: transparent; }
.btn-ghost:hover { border-color: var(--text-dim); text-decoration: none; }
.hero .meta { margin-top: 18px; font-size: 0.9rem; color: var(--text-dim); }

/* ---------- promise strip ---------- */
.promise {
  background: var(--navy-2);
  border-bottom: 1px solid var(--line);
  padding: 34px 0;
}
.promise .wrap { display: flex; gap: 14px; align-items: flex-start; }
.promise .badge {
  flex: none;
  font-size: 1.4rem;
}
.promise p { margin: 0; color: var(--text-muted); }
.promise strong { color: var(--text); }
.tag {
  display: inline-block;
  padding: 1px 8px;
  border-radius: 6px;
  font-size: 0.82em;
  font-weight: 650;
  border: 1px solid var(--line);
  color: var(--text);
  white-space: nowrap;
}

/* ---------- sections ---------- */
section { padding: 68px 0; }
section.banded {
  background: var(--navy-1);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.sub.center { margin-left: auto; margin-right: auto; }
section h2 {
  font-size: clamp(1.6rem, 3.4vw, 2.1rem);
  margin: 0 0 10px;
  letter-spacing: -0.015em;
}
section .sub { color: var(--text-muted); margin: 0 0 40px; max-width: 620px; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
}
.card {
  background: linear-gradient(180deg, var(--navy-2), var(--navy-1));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
}
.card h3 { margin: 0 0 8px; font-size: 1.12rem; }
.card p { margin: 0; color: var(--text-muted); font-size: 0.96rem; }
.card .ico {
  width: 40px; height: 40px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 10px;
  background: rgba(52, 209, 125, 0.13);
  margin-bottom: 14px;
  font-size: 1.25rem;
}

/* ---------- steps ---------- */
.steps { counter-reset: step; display: grid; gap: 16px; max-width: 760px; }
.step {
  display: flex; gap: 16px; align-items: flex-start;
  background: var(--navy-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 22px;
}
.step::before {
  counter-increment: step;
  content: counter(step);
  flex: none;
  width: 30px; height: 30px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 50%;
  background: var(--green);
  color: #06231a;
  font-weight: 700;
  font-size: 0.95rem;
}
.step h3 { margin: 2px 0 4px; font-size: 1.04rem; }
.step p { margin: 0; color: var(--text-muted); font-size: 0.95rem; }

/* ---------- requirements ---------- */
.req-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; max-width: 640px; }
.req-list li { display: flex; gap: 10px; color: var(--text-muted); }
.req-list li::before { content: "✓"; color: var(--green-bright); font-weight: 700; }

.note {
  margin-top: 26px;
  padding: 16px 18px;
  border-left: 3px solid var(--blue);
  background: var(--navy-2);
  border-radius: 0 10px 10px 0;
  color: var(--text-muted);
  font-size: 0.94rem;
  max-width: 680px;
}

/* ---------- download band ---------- */
.download-band {
  background:
    radial-gradient(900px 400px at 30% 120%, rgba(52, 209, 125, 0.16), transparent 60%),
    var(--navy-1);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  text-align: center;
}
.download-band .hash {
  margin-top: 20px;
  font-family: ui-monospace, "Cascadia Code", Consolas, monospace;
  font-size: 0.8rem;
  color: var(--text-dim);
  word-break: break-all;
}

/* ---------- footer ---------- */
.site-footer {
  background: var(--navy-0);
  padding: 40px 0;
  border-top: 1px solid var(--line);
  color: var(--text-dim);
  font-size: 0.9rem;
}
.site-footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 16px; }
.site-footer a { color: var(--text-muted); }
.site-footer .foot-links { display: flex; gap: 18px; flex-wrap: wrap; }

/* ---------- legal / doc pages ---------- */
.doc { padding: 56px 0 80px; }
.doc .wrap { max-width: 780px; }
.doc h1 { font-size: 2rem; margin: 0 0 6px; letter-spacing: -0.02em; }
.doc .updated { color: var(--text-dim); margin: 0 0 36px; font-size: 0.92rem; }
.doc h2 { font-size: 1.28rem; margin: 38px 0 12px; }
.doc h3 { font-size: 1.06rem; margin: 26px 0 8px; }
.doc p, .doc li { color: var(--text-muted); }
.doc code {
  background: var(--navy-2);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 1px 6px;
  font-size: 0.88em;
}
.doc a { color: var(--green-bright); }
.doc ul { padding-left: 22px; }
.back-link { display: inline-block; margin-bottom: 28px; color: var(--text-muted); font-size: 0.92rem; }

@media (max-width: 640px) {
  .nav-links a:not(.nav-cta) { display: none; }
  section { padding: 52px 0; }
  .promise .wrap { flex-direction: column; gap: 8px; }
}