:root {
  color-scheme: light;
  --paper: #fbfaf6;
  --card: #ffffff;
  --ink: #20242b;
  --muted: #69717d;
  --blue: #a9cef4;
  --blue-deep: #4f7fab;
  --red: #e96d61;
  --line: #20242b;
  --shadow: 0 14px 42px rgba(45, 66, 88, 0.12);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 18% 8%, rgba(169, 206, 244, 0.36), transparent 24rem),
    linear-gradient(180deg, #fff 0, var(--paper) 30rem);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC",
    "Noto Sans CJK SC", "Segoe UI", sans-serif;
  line-height: 1.75;
}

a { color: var(--blue-deep); }

.shell {
  width: min(920px, calc(100% - 32px));
  margin: 0 auto;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 22px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 900;
  letter-spacing: -0.03em;
  font-size: 1.25rem;
}

.brand img { width: 48px; height: 48px; object-fit: contain; }

nav { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px 18px; }
nav a { color: var(--muted); text-decoration: none; font-weight: 700; font-size: 0.94rem; }
nav a:hover { color: var(--ink); }

.hero {
  min-height: 62vh;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 48px;
  padding: 68px 0 92px;
}

.eyebrow {
  display: inline-block;
  padding: 5px 12px;
  border: 2px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-weight: 800;
  font-size: 0.82rem;
  transform: rotate(-1deg);
}

h1 {
  margin: 22px 0 14px;
  font-size: clamp(3rem, 9vw, 6.8rem);
  line-height: 0.98;
  letter-spacing: -0.075em;
}

.lead { max-width: 580px; color: var(--muted); font-size: 1.16rem; }

.hero-art {
  position: relative;
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  border: 3px solid var(--line);
  border-radius: 42% 48% 44% 50%;
  background: var(--blue);
  box-shadow: var(--shadow);
  transform: rotate(2deg);
}

.hero-art img { width: 72%; transform: rotate(-2deg); }
.hero-art::after {
  content: "◡";
  position: absolute;
  right: 8%;
  bottom: 3%;
  font-size: 4rem;
  color: var(--red);
  transform: rotate(-8deg);
}

.links { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 9px 18px;
  border: 2px solid var(--line);
  border-radius: 16px;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  font-weight: 850;
  box-shadow: 4px 5px 0 var(--blue);
}
.button.secondary { color: var(--ink); background: #fff; box-shadow: none; }

.document {
  margin: 32px auto 72px;
  padding: clamp(24px, 5vw, 54px);
  background: rgba(255, 255, 255, 0.94);
  border: 2px solid var(--line);
  border-radius: 28px 33px 26px 31px;
  box-shadow: var(--shadow);
}

.document h1 {
  font-size: clamp(2.25rem, 7vw, 4.25rem);
  letter-spacing: -0.055em;
}
.document h2 { margin-top: 2.1em; line-height: 1.25; }
.document h3 { margin-top: 1.7em; }
.document p, .document li { color: #3f4853; }
.document strong { color: var(--ink); }
.updated { color: var(--muted); font-size: 0.9rem; }

.notice {
  margin: 24px 0;
  padding: 16px 18px;
  border-left: 5px solid var(--red);
  background: #fff5ef;
  border-radius: 6px 15px 15px 6px;
}

.lang-divider {
  height: 2px;
  margin: 52px 0;
  background: repeating-linear-gradient(90deg, var(--line) 0 14px, transparent 14px 24px);
  opacity: 0.22;
}

footer {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding: 22px 0 40px;
  color: var(--muted);
  font-size: 0.88rem;
}

@media (max-width: 720px) {
  .topbar { align-items: flex-start; }
  nav { gap: 5px 12px; }
  .hero { grid-template-columns: 1fr; padding-top: 38px; }
  .hero-art { width: min(78vw, 330px); justify-self: center; }
}