:root {
  --bg: #f6f9fb;
  --card: #ffffff;
  --text: #1d2733;
  --sub: #5b6b7b;
  --line: #dde5ec;
  --accent: #1a73b8;
  --accent2: #06a9b8;
  --pink: #ffb3c1;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1419;
    --card: #182029;
    --text: #e8eef4;
    --sub: #9aabbb;
    --line: #2a3642;
    --accent: #6cb6f0;
    --accent2: #4fd2de;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  font-size: 16px;
  line-height: 1.8;
  overflow-wrap: anywhere;
}
a { color: var(--accent); }

header {
  position: sticky; top: 0; z-index: 1;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  padding: 10px 16px;
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px 20px;
}
.brand { display: flex; align-items: center; gap: 8px; text-decoration: none; color: var(--text); font-weight: 700; font-size: 18px; }
.brand img { border-radius: 9px; }
nav { display: flex; flex-wrap: wrap; gap: 4px 16px; font-size: 14px; }
nav a { color: var(--sub); text-decoration: none; }
nav a[aria-current] { color: var(--accent); font-weight: 700; }

main { max-width: 760px; margin: 0 auto; padding: 24px 16px 48px; }
h1 { font-size: 26px; line-height: 1.4; margin: 8px 0 20px; }
h2 { font-size: 20px; line-height: 1.4; margin: 36px 0 12px; padding-left: 10px; border-left: 4px solid var(--accent2); }
h3 { font-size: 17px; margin: 24px 0 8px; }
p, li { margin: 0 0 8px; }
ol, ul { padding-left: 1.5em; margin: 0 0 12px; }

.hero {
  text-align: center;
  padding: 32px 16px;
  border-radius: 24px;
  color: #fff;
  background: linear-gradient(135deg, #2557a7, #06a9b8);
  margin-bottom: 28px;
}
.hero img { width: 112px; height: 112px; border-radius: 26px; box-shadow: 0 6px 20px rgb(0 0 0 / .25); }
.hero h1 { margin: 16px 0 6px; font-size: 28px; }
.hero p { margin: 0; font-size: 17px; opacity: .95; }
.hero .soon { display: inline-block; margin-top: 16px; padding: 6px 16px; border-radius: 999px; background: rgb(255 255 255 / .2); font-size: 14px; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 16px 18px; }
.card h3 { margin: 0 0 6px; font-size: 16px; }
.card p { margin: 0; color: var(--sub); font-size: 15px; }

.steps { counter-reset: s; list-style: none; padding: 0; }
.steps li { counter-increment: s; position: relative; padding-left: 40px; margin-bottom: 12px; }
.steps li::before {
  content: counter(s); position: absolute; left: 0; top: 2px;
  width: 28px; height: 28px; border-radius: 50%;
  background: var(--accent2); color: #fff; font-weight: 700; font-size: 14px;
  display: flex; align-items: center; justify-content: center;
}

details { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 16px; margin-bottom: 10px; }
summary { cursor: pointer; font-weight: 700; }
details[open] summary { margin-bottom: 8px; }
details p:last-child { margin-bottom: 0; }

.note { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 16px; color: var(--sub); font-size: 15px; }
.mail { font-size: 18px; font-weight: 700; }

.table { overflow-x: auto; margin: 0 0 16px; }
table { border-collapse: collapse; width: 100%; font-size: 14px; background: var(--card); }
th, td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; vertical-align: top; }
th { background: color-mix(in srgb, var(--accent2) 12%, var(--card)); }
.doc .date { margin-top: 32px; color: var(--sub); }

footer { border-top: 1px solid var(--line); padding: 20px 16px; text-align: center; color: var(--sub); font-size: 14px; }
footer p { margin: 0; }