:root {
  --green: #0d7a32;
  --green-dark: #093d22;
  --green-soft: #eaf5ed;
  --blue: #2e80c4;
  --ink: #102015;
  --muted: #5f7067;
  --line: #dce8df;
  --white: #ffffff;
  --shadow: 0 24px 70px rgba(11, 47, 27, .14);
  --radius: 28px;
  --orange: #f28e08;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: #fbfdfb;
  line-height: 1.55;
}
a { color: inherit; }
img { max-width: 100%; display: block; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(20px, 5vw, 64px);
  background: rgba(255,255,255,.86);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(220,232,223,.8);
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -.02em;
}
.brand img { width: 44px; height: 44px; border-radius: 12px; }
nav { display: flex; gap: 22px; color: var(--muted); font-weight: 650; }
nav a { text-decoration: none; }
nav a:hover { color: var(--green); }
.section-pad { padding: clamp(54px, 8vw, 104px) clamp(20px, 5vw, 64px); }
.hero {
  display: grid;
  grid-template-columns: minmax(0, .92fr) minmax(0, 1.2fr);
  align-items: center;
  gap: clamp(36px, 6vw, 84px);
  min-height: 760px;
  background:
    radial-gradient(circle at 85% 10%, rgba(46,128,196,.18), transparent 30%),
    linear-gradient(180deg, #fff, var(--green-soft));
}
.eyebrow {
  color: var(--green);
  font-size: .78rem;
  font-weight: 850;
  letter-spacing: .15em;
  text-transform: uppercase;
  margin: 0 0 14px;
}
h1, h2, h3 { line-height: 1.05; letter-spacing: -.055em; margin: 0; }
h1 { font-size: clamp(3rem, 6.2vw, 6.8rem); max-width: 850px; }
h2 { font-size: clamp(2.2rem, 4.2vw, 4.6rem); }
h3 { font-size: clamp(1.55rem, 2.2vw, 2.35rem); }
.lead { font-size: clamp(1.15rem, 1.55vw, 1.42rem); color: var(--muted); max-width: 710px; margin: 24px 0 0; }
.button-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 34px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 54px;
  padding: 15px 22px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 800;
  border: 2px solid transparent;
}
.primary { background: var(--blue); color: white; box-shadow: 0 12px 30px rgba(13,122,50,.22); }
.secondary { background: var(--orange); color: white; box-shadow: 0 12px 30px rgba(13,122,50,.22); }
.secondary.light { background: rgba(255,255,255,.1); color: white; border-color: rgba(255,255,255,.35); }
.hero-art { position: relative; min-height: 530px; }
.ipad { border-radius: 36px; filter: drop-shadow(var(--shadow)); transform: rotate(-1deg); }
.iphone {
  position: absolute;
  right: 3%;
  bottom: -44px;
  width: min(34%, 260px);
  filter: drop-shadow(0 22px 50px rgba(11,47,27,.24));
}
.strip { overflow: hidden; padding: 24px 0; background: var(--green-dark); }
.strip img { width: 1120px; max-width: none; margin: 0 auto; opacity: .95; }
.section-heading { max-width: 900px; margin-bottom: 36px; }
.narrow { max-width: 820px; margin-inline: auto; text-align: center; }
.products { background: white; }
.product-grid { display: grid; grid-template-columns: 1fr 1.15fr; gap: 24px; }
.product-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(24px, 3vw, 38px);
  box-shadow: var(--shadow);
}
.product-card p { color: var(--muted); font-size: 1.05rem; }
.app-card { display: flex; flex-direction: column; justify-content: space-between; gap: 30px; background: linear-gradient(180deg, #fff, #eff8f1); }
.book-card { display: grid; grid-template-columns: minmax(160px, .48fr) 1fr; gap: 28px; align-items: center; }
.mini-icon { width: 84px; border-radius: 22px; margin-bottom: 22px; }
.book-cover { border-radius: 18px; box-shadow: 0 16px 40px rgba(0,0,0,.16); }
.tag { color: var(--blue) !important; font-weight: 800; margin: 0 0 10px; }
.inside { display: grid; grid-template-columns: .9fr 1.1fr; gap: clamp(34px, 6vw, 80px); align-items: center; background: var(--green-soft); }
.inside-copy > p:not(.eyebrow) { color: var(--muted); font-size: 1.12rem; }
.feature-list { display: grid; gap: 14px; margin-top: 28px; }
.feature-list div { background: rgba(255,255,255,.78); border: 1px solid var(--line); border-radius: 18px; padding: 18px 20px; }
.feature-list strong { display: block; font-size: 1.06rem; }
.feature-list span { color: var(--muted); }
.diagram-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.diagram-grid img, .wide-gallery img { border-radius: 18px; border: 1px solid rgba(255,255,255,.4); box-shadow: 0 10px 30px rgba(11,47,27,.15); background: var(--green-dark); }
.gallery { background: #fff; }
.wide-gallery { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-top: 34px; }
.cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 34px;
  color: white;
  background:
    linear-gradient(rgba(9,61,34,.91), rgba(9,61,34,.91)),
    url("assets/crossing_game.png") center/cover;
}
.cta .eyebrow { color: #a6edbb; }
.cta p { max-width: 760px; color: rgba(255,255,255,.82); font-size: 1.14rem; }
.centered { justify-content: center; min-width: max-content; }
footer { padding: 34px clamp(20px, 5vw, 64px); color: var(--muted); display: flex; justify-content: space-between; gap: 20px; border-top: 1px solid var(--line); background: white; }
footer p { margin: 0; }
footer a { color: var(--green); font-weight: 750; }
@media (max-width: 980px) {
  .hero, .inside, .product-grid, .cta { grid-template-columns: 1fr; display: grid; }
  .hero { min-height: auto; }
  .hero-art { min-height: auto; padding-bottom: 55px; }
  .book-card { grid-template-columns: 180px 1fr; }
  .wide-gallery { grid-template-columns: repeat(2, 1fr); }
  .cta { text-align: left; }
  .centered { justify-content: flex-start; min-width: 0; }
}
@media (max-width: 680px) {
  .site-header { align-items: flex-start; flex-direction: column; }
  nav { width: 100%; justify-content: space-between; gap: 10px; font-size: .95rem; }
  .iphone { width: 42%; right: 0; }
  .book-card { grid-template-columns: 1fr; }
  .book-cover { max-width: 240px; }
  .diagram-grid, .wide-gallery { grid-template-columns: 1fr; }
  footer { flex-direction: column; }
}