:root {
  color-scheme: light;
  --page: #f6f9fd;
  --surface: rgba(255, 255, 255, 0.82);
  --text: #142033;
  --muted: #64748b;
  --line: #dce6f2;
  --blue: #2563eb;
  --cyan: #20bde4;
  --warning: #9a5b00;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 12% 0%, rgba(32, 189, 228, 0.14), transparent 28rem),
    radial-gradient(circle at 90% 12%, rgba(37, 99, 235, 0.12), transparent 30rem),
    var(--page);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }

.shell {
  width: min(760px, calc(100% - 40px));
  margin: 0 auto;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 28px 0 18px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--text);
  font-weight: 750;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.mark {
  display: grid;
  width: 36px;
  height: 36px;
  place-items: center;
  border: 1px solid rgba(37, 99, 235, 0.16);
  border-radius: 11px;
  background: linear-gradient(145deg, #ffffff, #e7f2ff);
  box-shadow: 0 7px 22px rgba(37, 99, 235, 0.13);
}

.mark svg { width: 25px; height: 25px; }

nav { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 16px; }
nav a { color: var(--muted); font-size: 14px; font-weight: 600; text-decoration: none; }
nav a[aria-current="page"], nav a:hover { color: var(--blue); }

main {
  margin-top: 12px;
  padding: clamp(28px, 6vw, 52px) clamp(22px, 6vw, 54px) 58px;
  border: 1px solid rgba(220, 230, 242, 0.9);
  border-radius: 28px;
  background: var(--surface);
  box-shadow: 0 24px 70px rgba(29, 65, 112, 0.1);
  backdrop-filter: blur(16px);
}

h1, h2, h3 { letter-spacing: -0.025em; }
h1 { margin: 0 0 6px; font-size: clamp(32px, 6vw, 46px); line-height: 1.12; }
h2 { margin: 36px 0 10px; font-size: 21px; line-height: 1.3; }
h3 { margin: 24px 0 8px; font-size: 17px; line-height: 1.35; }
p { margin: 0 0 15px; }
ul { margin: 8px 0 18px; padding-left: 23px; }
li + li { margin-top: 7px; }

.meta { margin-bottom: 28px; color: var(--muted); font-size: 14px; }
.lede { font-size: 18px; line-height: 1.65; }
.notice {
  margin: 24px 0;
  padding: 17px 18px;
  border-left: 4px solid var(--cyan);
  border-radius: 4px 14px 14px 4px;
  background: #eefaff;
}
.notice strong { display: block; margin-bottom: 3px; }
.contact-card {
  margin: 24px 0 4px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(247, 251, 255, 0.88);
}
.contact-card p:last-child { margin-bottom: 0; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 22px;
  padding: 26px 2px 42px;
  color: var(--muted);
  font-size: 13px;
}
footer div:last-child { text-align: right; }
footer a { margin-left: 14px; color: var(--muted); }

@media (max-width: 620px) {
  header { align-items: flex-start; flex-direction: column; }
  nav { justify-content: flex-start; }
  main { border-radius: 22px; }
  footer { flex-direction: column; }
  footer div:last-child { text-align: left; }
  footer a { margin: 0 14px 0 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}