:root {
  color-scheme: light;
  --ink: #173c2a;
  --muted: #557064;
  --leaf: #2f9e57;
  --leaf-dark: #1f7040;
  --sky: #dff4ff;
  --rose: #e85d75;
  --sun: #f6c94c;
  --line: #d8e6dc;
  --paper: #ffffff;
  --mist: #f4faf6;
  --header-height: 68px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, "Noto Sans SC", "Noto Sans JP", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  letter-spacing: 0;
}

body, button, a { -webkit-font-smoothing: antialiased; }

a { color: inherit; }

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

[hidden] { display: none !important; }

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  min-height: var(--header-height);
  border-bottom: 1px solid rgba(23, 60, 42, 0.12);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(12px);
}

.header-inner {
  width: min(1180px, calc(100% - 32px));
  min-height: var(--header-height);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: var(--ink);
  font-size: 21px;
  font-weight: 900;
  text-decoration: none;
}

.brand-mark {
  width: 36px;
  height: 36px;
  flex: 0 0 36px;
  overflow: hidden;
  border: 0;
  border-radius: 8px;
  background: url("/assets/stackyq-icon-96.png") center / cover no-repeat;
  box-shadow: 0 2px 7px rgba(23, 60, 42, 0.18);
  color: transparent;
  font-size: 0;
}

.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 22px;
  color: #315544;
  font-size: 14px;
  font-weight: 700;
}

.site-nav a { text-decoration: none; }
.site-nav a:hover, .site-nav a:focus-visible { color: var(--leaf-dark); }

.language-switch {
  flex: 0 0 auto;
  display: inline-grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid #b9cec0;
  border-radius: 8px;
  overflow: hidden;
  background: #fff;
}

.language-switch button {
  min-width: 38px;
  min-height: 34px;
  padding: 0 9px;
  border: 0;
  border-right: 1px solid #d2dfd6;
  background: transparent;
  color: #426250;
  cursor: pointer;
  font: inherit;
  font-size: 12px;
  font-weight: 800;
}

.language-switch button:last-child { border-right: 0; }
.language-switch button[aria-pressed="true"] { background: var(--ink); color: #fff; }

.hero {
  position: relative;
  min-height: min(760px, calc(100svh - var(--header-height) - 42px));
  display: flex;
  align-items: center;
  overflow: hidden;
  isolation: isolate;
  background-image: url("/assets/pk_arena.webp");
  background-position: center 44%;
  background-size: cover;
}

.hero::before {
  position: absolute;
  z-index: -1;
  inset: 0;
  content: "";
  background: rgba(11, 46, 27, 0.54);
}

.hero-content {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 78px 0 84px;
  color: #fff;
}

.hero-copy { max-width: 690px; }

.hero-kicker {
  margin: 0 0 16px;
  color: #fff3b0;
  font-size: 15px;
  font-weight: 900;
}

.hero h1 {
  margin: 0;
  font-size: 68px;
  line-height: 1;
  font-weight: 950;
}

.hero-tagline {
  margin: 22px 0 0;
  color: #fff;
  font-size: 30px;
  line-height: 1.35;
  font-weight: 850;
}

.hero-summary {
  max-width: 620px;
  margin: 18px 0 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: 17px;
  line-height: 1.75;
}

.hero-actions { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 12px; }

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 850;
  text-decoration: none;
}

.button-primary { background: var(--sun); color: #193323; }
.button-secondary { border-color: rgba(255,255,255,.68); background: rgba(255,255,255,.1); color: #fff; }

.signal-band { border-bottom: 1px solid var(--line); background: var(--sky); }
.signal-grid {
  width: min(1020px, calc(100% - 32px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}
.signal {
  min-height: 96px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border-right: 1px solid #bedbe8;
  text-align: center;
}
.signal:last-child { border-right: 0; }
.signal strong { font-size: 22px; }
.signal span { margin-top: 5px; color: #466b78; font-size: 13px; }

.section { padding: 84px 0; }
.section-alt { background: var(--mist); }
.section-rose { background: #fff4f5; }
.section-inner { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.section-heading { max-width: 740px; margin-bottom: 34px; }
.eyebrow { margin: 0 0 9px; color: var(--leaf-dark); font-size: 13px; font-weight: 900; }
.section h2 { margin: 0; font-size: 38px; line-height: 1.25; }
.section-lead { margin: 14px 0 0; color: var(--muted); font-size: 16px; line-height: 1.75; }

.mode-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.mode-card { overflow: hidden; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.mode-card img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; object-position: center 34%; }
.mode-body { padding: 20px; }
.mode-body h3 { margin: 0; font-size: 20px; }
.mode-body p { margin: 10px 0 0; color: var(--muted); font-size: 14px; line-height: 1.7; }
.mode-label { display: inline-block; margin-bottom: 10px; color: var(--rose); font-size: 12px; font-weight: 900; }

.feature-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 48px; }
.feature {
  min-height: 150px;
  padding: 28px 0;
  border-top: 1px solid var(--line);
}
.feature:nth-child(-n+2) { border-top: 0; }
.feature-index { color: var(--rose); font-size: 13px; font-weight: 950; }
.feature h3 { margin: 8px 0 0; font-size: 20px; }
.feature p { margin: 9px 0 0; color: var(--muted); line-height: 1.7; }

.split-band { display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }
.split-band img { width: 100%; max-height: 520px; object-fit: cover; object-position: center 42%; border-radius: 8px; }
.plain-list { margin: 24px 0 0; padding: 0; list-style: none; }
.plain-list li { padding: 13px 0; border-bottom: 1px solid #efcdd2; line-height: 1.6; }
.plain-list strong { color: var(--rose); }

.site-footer { padding: 42px 0; background: #173c2a; color: rgba(255,255,255,.84); }
.footer-inner { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.footer-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 36px; }
.footer-brand { color: #fff; font-size: 22px; font-weight: 900; }
.footer-tagline { margin: 8px 0 0; color: rgba(255,255,255,.64); }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 18px; font-size: 13px; font-weight: 700; }
.footer-links a { text-decoration: none; }
.footer-bottom { margin-top: 30px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.16); display: flex; justify-content: space-between; gap: 20px; color: rgba(255,255,255,.58); font-size: 12px; }

.legal-hero { padding: 64px 0 46px; border-bottom: 1px solid var(--line); background: var(--sky); }
.legal-hero-inner, .legal-content { width: min(860px, calc(100% - 32px)); margin: 0 auto; }
.legal-hero h1 { margin: 0; font-size: 42px; line-height: 1.25; }
.legal-hero p { margin: 14px 0 0; color: #456777; line-height: 1.7; }
.legal-content { padding-top: 56px; padding-bottom: 88px; }
.legal-content h2 { margin: 42px 0 12px; font-size: 23px; }
.legal-content h2:first-child { margin-top: 0; }
.legal-content h3 { margin: 26px 0 8px; font-size: 18px; }
.legal-content p, .legal-content li { color: #445f52; font-size: 15px; line-height: 1.85; }
.legal-content ul, .legal-content ol { padding-left: 23px; }
.legal-content a { color: var(--leaf-dark); font-weight: 750; }
.legal-note { margin: 24px 0; padding: 18px 20px; border-left: 4px solid var(--sun); background: #fffbea; }
.legal-meta { color: #617a6e; font-size: 13px; font-weight: 750; }

.support-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin: 30px 0 48px; }
.support-item { padding: 22px; border: 1px solid var(--line); border-radius: 8px; }
.support-item h2 { margin: 0; font-size: 18px; }
.support-item p { margin-bottom: 0; }
.faq { border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary { padding: 20px 0; cursor: pointer; font-weight: 800; }
.faq details p { margin: -4px 0 20px; }

@media (max-width: 900px) {
  .site-nav { display: none; }
  .hero h1 { font-size: 54px; }
  .hero-tagline { font-size: 25px; }
  .mode-grid { grid-template-columns: repeat(2, 1fr); }
  .split-band { grid-template-columns: 1fr; }
  .split-band img { max-height: 430px; }
  .support-grid { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  :root { --header-height: 62px; }
  .header-inner { width: min(100% - 20px, 1180px); gap: 10px; }
  .brand { font-size: 18px; }
  .brand-mark { width: 32px; height: 32px; flex-basis: 32px; font-size: 0; }
  .language-switch { margin-left: auto; }
  .language-switch button { min-width: 34px; padding: 0 7px; }
  .hero { min-height: calc(84svh - var(--header-height)); background-position: center 36%; }
  .hero-content { width: calc(100% - 32px); padding: 54px 0 58px; }
  .hero h1 { font-size: 46px; }
  .hero-tagline { font-size: 22px; }
  .hero-summary { font-size: 15px; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .signal-grid { width: 100%; }
  .signal { min-height: 84px; }
  .signal strong { font-size: 18px; }
  .section { padding: 62px 0; }
  .section h2 { font-size: 30px; }
  .mode-grid, .feature-grid { grid-template-columns: 1fr; }
  .feature:nth-child(2) { border-top: 1px solid var(--line); }
  .footer-top, .footer-bottom { flex-direction: column; }
  .footer-links { justify-content: flex-start; }
  .legal-hero { padding: 48px 0 34px; }
  .legal-hero h1 { font-size: 32px; }
  .legal-content { padding-top: 40px; padding-bottom: 64px; }
}