:root{
  --bg: #f6fbff;
  --card: rgba(255,255,255,0.88);
  --stroke: #cce0f5;
  --text: #0d2a3f;
  --muted: #325a78;
  --accent: #0078F8;
  --shadow: 0 16px 50px rgba(0,0,0,0.08);
  --r16: 16px;
  --r20: 20px;
}

*{ box-sizing: border-box; }

/* 変更：height:100% をやめる */
html, body{ height: auto; }

/* 追加：背景は html に持たせる（継ぎ目防止） */
html{
  min-height: 100vh;
  background:
    radial-gradient(1200px 800px at 10% -10%, rgba(0,120,248,0.10), transparent 60%),
    radial-gradient(900px 700px at 95% 0%, rgba(0,120,248,0.08), transparent 55%),
    var(--bg);
  background-repeat: no-repeat;
  background-attachment: fixed;
}

/* 変更：body から背景を外して透明にする */
body{
  margin: 0;
  min-height: 100vh;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, "Noto Sans", "Apple Color Emoji","Segoe UI Emoji";
  color: var(--text);
  background: transparent;
}


.container{
  width: min(980px, calc(100% - 32px));
  margin: 0 auto;
}

.header{
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(10px);
  background: rgba(246, 251, 255, 0.75);
  border-bottom: 1px solid var(--stroke);
}

.header__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding: 14px 0;
}

.brand{
  display:flex;
  align-items:center;
  gap: 10px;
  text-decoration:none;
  color: var(--text);
  font-weight: 800;
  letter-spacing: 0.2px;
}
.brand__dot{
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 6px 16px rgba(0,120,248,0.25);
}
.brand__text{ font-size: 16px; }

.header__nav{
  display:flex;
  gap: 14px;
  align-items:center;
}
.navlink{
  text-decoration:none;
  color: var(--muted);
  font-weight: 650;
  padding: 8px 10px;
  border-radius: 10px;
}
.navlink:hover{
  background: rgba(0,120,248,0.08);
  color: var(--text);
}

.card{
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: var(--r20);
  box-shadow: var(--shadow);
  padding: 18px 18px;
  margin: 18px 0;
}

.hero{ padding: 22px 18px; }
.hero__title{
  margin: 0 0 8px;
  font-size: 24px;
  line-height: 1.25;
}
.hero__subtitle{
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.section-title{
  margin: 0 0 14px;
  font-size: 18px;
  color: #004080;
  letter-spacing: 0.2px;
}

.note{
  margin-top: 14px;
  padding: 12px 12px;
  border-radius: var(--r16);
  border: 1px dashed var(--stroke);
  background: rgba(0,120,248,0.06);
}
.note__title{
  font-weight: 800;
  margin-bottom: 6px;
}
.note__body{
  color: var(--muted);
  line-height: 1.6;
}

.grid{
  margin: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 16px;
}
.item{
  padding: 12px 12px;
  border-radius: 14px;
  border: 1px solid rgba(204,224,245,0.9);
  background: rgba(255,255,255,0.62);
}
dt{
  font-weight: 800;
  color: #0f3b5a;
  margin-bottom: 6px;
}
dd{
  margin: 0;
  color: var(--text);
  line-height: 1.65;
}
a{
  color: var(--accent);
  text-decoration: none;
  font-weight: 700;
}
a:hover{ text-decoration: underline; }

.text p{
  margin: 0 0 12px;
  line-height: 1.75;
  color: var(--text);
}
.text p:last-child{ margin-bottom: 0; }

.footer{
  margin: 26px 0 34px;
  padding: 0;
  border: none;
  background: transparent;
  box-shadow: none;
}
.footer__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  padding: 10px 4px;
  border-top: 1px solid var(--stroke);
}
.small{
  font-size: 12px;
  color: var(--muted);
}

.btn{
  display:inline-block;
  padding: 10px 14px;
  border-radius: 12px;
  border: 2px solid var(--accent);
  background: var(--accent);
  color: white;
  font-weight: 800;
  text-decoration:none;
}
.btn:hover{ filter: brightness(0.96); }

@media (max-width: 760px){
  .grid{ grid-template-columns: 1fr; }
  .hero__title{ font-size: 22px; }
}