:root {
  color-scheme: light;
  --bg: #f3f5f7;
  --card: #ffffff;
  --navy: #173b73;
  --muted: #687078;
  --border: #d9dee5;
  --green: #398441;
  --green-dark: #2f7037;
}

* {
  box-sizing: border-box;
}

html, body {
  min-height: 100%;
}

html {
  background: var(--bg);
}

body {
  margin: 0;
  background:
    radial-gradient(circle at top, rgba(57,132,65,.08), transparent 34rem),
    var(--bg);
  color: var(--navy);
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
}

.page-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding:
    max(22px, env(safe-area-inset-top))
    16px
    max(22px, env(safe-area-inset-bottom));
}

.app-card {
  width: min(100%, 680px);
  padding: 34px 28px 30px;
  text-align: center;
  background: rgba(255,255,255,.98);
  border: 1px solid var(--border);
  border-radius: 30px;
  box-shadow: 0 12px 34px rgba(26, 52, 78, .10);
}

.app-logo {
  display: block;
  width: min(60vw, 260px);
  height: auto;
  margin: 0 auto 20px;
}

.company-name {
  margin: 0 0 10px;
  color: var(--muted);
  font-size: clamp(16px, 3vw, 22px);
  font-weight: 700;
  letter-spacing: .04em;
}

h1 {
  margin: 0 0 20px;
  color: var(--navy);
  font-size: clamp(36px, 7vw, 58px);
  line-height: 1.15;
}

.description {
  max-width: 560px;
  margin: 0 auto 28px;
  color: var(--muted);
  font-size: clamp(18px, 4vw, 28px);
  line-height: 1.75;
}

.primary-button {
  display: block;
  width: 100%;
  padding: 22px 18px;
  color: #fff;
  background: var(--green);
  border-radius: 18px;
  text-decoration: none;
  font-size: clamp(22px, 5vw, 32px);
  font-weight: 800;
  line-height: 1.2;
  box-shadow: 0 6px 14px rgba(57, 132, 65, .24);
  transition: transform .12s ease, background-color .12s ease;
}

.primary-button:hover {
  background: var(--green-dark);
}

.primary-button:active {
  transform: scale(.99);
}

.primary-button:focus-visible {
  outline: 4px solid rgba(57,132,65,.25);
  outline-offset: 4px;
}

.install-guide {
  display: grid;
  gap: 6px;
  margin-top: 24px;
  padding: 16px;
  color: #70777f;
  background: #f7f9fa;
  border-radius: 14px;
  font-size: clamp(14px, 3vw, 17px);
  line-height: 1.65;
}

.status {
  min-height: 1.3em;
  margin: 12px 0 0;
  color: var(--green-dark);
  font-size: 14px;
}

@media (max-width: 420px) {
  .app-card {
    padding: 28px 20px 26px;
    border-radius: 24px;
  }

  .app-logo {
    width: min(68vw, 240px);
  }
}