:root {
  color-scheme: dark;
  --bg: #1d232f;
  --surface: #111824;
  --line: #3a4659;
  --text: #f5f7fa;
  --muted: #b5bdc9;
  --subtle: #919aa8;
  --accent: #f2c94c;
  --page-width: 1080px;
  --reading-width: 760px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  font-size: 16px;
  line-height: 1.8;
}

a { color: var(--accent); text-underline-offset: 0.2em; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }

.page {
  width: min(var(--page-width), calc(100% - 48px));
  margin: 0 auto;
  padding: 34px 0 44px;
}

.topline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}

.topline__brand {
  color: var(--text);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-decoration: none;
}

.topline__links { display: flex; flex-wrap: wrap; gap: 24px; }
.topline__links a { color: var(--muted); text-decoration: none; }
.topline__links a:hover { color: var(--text); text-decoration: underline; }

h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { color: var(--text); }

h1 {
  margin-bottom: 24px;
  font-size: clamp(32px, 4.5vw, 56px);
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.25;
}

h2 { margin-bottom: 18px; font-size: clamp(25px, 3vw, 32px); font-weight: 600; line-height: 1.4; }
h3 { margin-bottom: 8px; font-size: 19px; font-weight: 600; line-height: 1.5; }
p { margin-bottom: 18px; color: var(--muted); }

.overline {
  margin-bottom: 22px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.lead { max-width: 620px; font-size: 19px; line-height: 1.85; }
.small-copy { color: var(--subtle); font-size: 14px; line-height: 1.75; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 0.88fr);
  align-items: start;
  gap: clamp(36px, 7vw, 96px);
  padding: 60px 0 48px;
  border-bottom: 1px solid var(--line);
}

.hero__copy { max-width: 560px; padding-top: 42px; }
.hero__headline-line { display: block; white-space: nowrap; }
.hero__copy .overline { margin-bottom: 14px; }
.hero__copy h1 { margin-bottom: 16px; }
.hero__copy .lead { margin-bottom: 22px; }
.app-store-link {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 10px 22px;
  border-radius: 10px;
  background: var(--accent);
  color: var(--bg);
  font-weight: 700;
  text-decoration: none;
}
.app-store-link:hover { background: #dfb741; color: var(--bg); text-decoration: none; }
.hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 26px 0 0;
  padding: 14px 0 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
  list-style: none;
}

.hero__figure { justify-self: center; width: min(100%, 320px); margin: 0; }
.hero__image {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid #374152;
  border-radius: 34px;
  background: var(--surface);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.16);
}
.hero__caption { margin-top: 14px; color: var(--subtle); font-size: 13px; text-align: center; }

.section { padding: 68px 0; border-bottom: 1px solid var(--line); }
.section > p { max-width: var(--reading-width); }
.section__intro { max-width: 680px; }
.section__intro p:last-child { margin-bottom: 0; }

.feature-list { margin-top: 40px; border-top: 1px solid var(--line); }
.feature {
  display: grid;
  grid-template-columns: minmax(180px, 0.48fr) minmax(0, 1fr);
  gap: 28px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}
.feature h3, .feature p { margin-bottom: 0; }
.feature p { max-width: 650px; }

.secondary-features {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  margin-top: 48px;
}
.secondary-features h3 { font-size: 17px; }
.secondary-features p { margin-bottom: 0; font-size: 15px; line-height: 1.75; }

.privacy-summary { max-width: var(--reading-width); }
.privacy-summary p:last-child { margin-bottom: 0; }

.footer { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 24px; color: var(--subtle); font-size: 13px; }
.footer a { color: var(--muted); }

.policy { max-width: var(--reading-width); }
.policy__header { padding: 70px 0 42px; }
.policy__header h1 { font-size: clamp(36px, 4.5vw, 52px); }
.policy__updated { margin-bottom: 0; color: var(--subtle); font-size: 13px; }
.policy section { padding: 34px 0; border-top: 1px solid var(--line); }
.policy section h2 { margin-bottom: 16px; font-size: 23px; }
.policy section h3 { margin: 26px 0 10px; font-size: 17px; }
.policy section p:last-child { margin-bottom: 0; }
.policy ul { margin: 0 0 18px; padding-left: 1.4em; color: var(--muted); }
.policy li { margin-bottom: 8px; }
.policy .num { display: inline-block; width: 2.3em; color: var(--accent); font-size: 14px; font-variant-numeric: tabular-nums; }
.policy .strong { color: var(--text); font-weight: 600; }
.policy .links { overflow-wrap: anywhere; }

@media (max-width: 760px) {
  .page { width: min(100% - 36px, 640px); padding-top: 22px; }
  .topline { align-items: flex-start; gap: 14px; }
  .topline__links { gap: 10px 16px; justify-content: flex-end; }
  .hero { grid-template-columns: 1fr; gap: 26px; padding: 32px 0 48px; }
  .hero__copy { padding-top: 0; }
  .hero__figure { width: min(92%, 320px); }
  .section { padding: 52px 0; }
  .feature { grid-template-columns: 1fr; gap: 8px; }
  .secondary-features { grid-template-columns: 1fr; gap: 24px; margin-top: 36px; }
  .policy__header { padding: 56px 0 34px; }
}

@media (max-width: 480px) {
  h1 { font-size: clamp(32px, 9vw, 40px); }
  .lead { font-size: 17px; }
  .app-store-link { width: 100%; }
  .policy section h2 { font-size: 21px; }
}