/* ===== Base & Theme ===== */
:root{
  --bg: #fffef9;
  --text: #263238;
  --muted: #607d8b;
  --brand: #FFB703;  /* 明るいイエロー */
  --brand-2:#219EBC; /* さわやかなブルー */
  --brand-3:#a5bc21; /* さわやかなグリーン */
  --accent:#FB8500;  /* オレンジ */
  --accent-2:#0075fb;  /* 青 */
  --accent-3:#11fb00;  /* 緑 */
  --card:#ffffff;
  --shadow: 0 10px 24px rgba(0,0,0,.08);
  --radius:18px;
}

*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Hiragino Kaku Gothic ProN", "Noto Sans JP", "Yu Gothic", "Meiryo", sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.75;
}
img{max-width:100%; display:block}

.container{
  width:min(1100px, 92vw);
  margin-inline:auto;
}

/* ===== Header / Nav ===== */
.site-header{
  position:sticky; top:0; z-index:50;
  background:rgba(255,255,255,.85);
  backdrop-filter:saturate(180%) blur(10px);
  border-bottom:1px solid #eee;
}
.nav{
  display:flex; align-items:center; justify-content:space-between;
  gap:12px; padding:10px 0;
}
.brand{display:flex; align-items:center; gap:12px; text-decoration:none; color:var(--text)}
.brand-mark{
  display:inline-grid; place-items:center;
  width:36px; height:36px; border-radius:10px;
  background:linear-gradient(135deg, var(--brand), var(--accent));
  color:#1b1b1b; font-weight:900;
  letter-spacing:.5px;
}
.brand-text{font-weight:700}

.menu{display:flex; gap:14px}
.menu a{
  text-decoration:none; color:var(--text); font-weight:600;
  padding:8px 10px; border-radius:10px;
}
.menu a:hover{background:#f5f7f8}

.nav-toggle{
  display:none; background:none; border:0; cursor:pointer;
}
.nav-toggle .bar{
  display:block; width:24px; height:2px; background:#333; margin:5px 0; border-radius:2px;
}

/* ===== Hero ===== */
.hero{
  position:relative;
  padding:42px 0 28px;
  overflow:hidden;
}
.hero-title{
  font-size:clamp(22px, 3.2vw, 38px);
  margin:8px 0 6px;
}
.hero-lead{
  color:var(--muted);
  margin:0 0 18px;
}
.hero-grid{
  display:grid; gap:14px;
  grid-template-columns: 1fr 1fr;
  grid-auto-rows: 1fr;
}
.hero-card{
  background:var(--card);
  border-radius:16px; overflow:hidden;
  box-shadow:var(--shadow);
}
.hero-card img{aspect-ratio: 16/10; object-fit:cover}
.hero-card figcaption{
  padding:10px 12px; font-size:.95rem; color:#37474f;
}

.blob{
  position:absolute; filter:blur(48px); opacity:.35; z-index:-1;
  border-radius:50%;
}
.blob-a{ width:360px; height:360px; background:var(--brand); right:-120px; top:-60px }
.blob-b{ width:420px; height:420px; background:var(--brand-2); left:-160px; bottom:-120px }

/* ===== Sections ===== */
.section{ padding:56px 0 }
.section.alt{ background:#fafbfc }
.section-title{
  font-size:clamp(20px, 2.6vw, 30px);
  margin:0 0 18px; position:relative;
}
.section-title::after{
  content:""; display:block; width:56px; height:6px;
  background: linear-gradient(90deg, var(--brand), var(--accent));
  border-radius:6px; margin-top:8px;
}

.grid{ display:grid; gap:16px }
.cards-2{ grid-template-columns: 1fr; }
.cards-3{ grid-template-columns: 1fr; }

@media (min-width: 720px){
  .cards-2{ grid-template-columns: 1fr 1fr; }
  .cards-3{ grid-template-columns: 1fr 1fr 1fr; }
}

/* ===== Cards ===== */
.card{
  background:var(--card);
  border-radius:var(--radius);
  overflow:hidden;
  box-shadow:var(--shadow);
  display:flex; flex-direction:column;
}
.card img{ width:100%; height:auto; aspect-ratio: 16/10; object-fit:cover }
.card-body{ padding:14px 16px }
.card h3{ margin:6px 0 6px; font-size:1.08rem }
.card .meta{ color:var(--muted); font-size:.9rem }
.tags{ list-style:none; padding:0; margin:10px 0 0; display:flex; gap:8px; flex-wrap:wrap }
.tags li{ background:#eef6ff; color:#1565c0; border-radius:999px; padding:4px 10px; font-size:.85rem }

.person img{ aspect-ratio: 1/1; }
.book img{ aspect-ratio: 4/3; }
.app img{ aspect-ratio: 16/10; }

.actions{ display:flex; gap:10px; margin-top:10px; flex-wrap:wrap }
.btn{
  display:inline-block; text-decoration:none; color:#0d1720;
  background:#f0f3f6; padding:8px 12px; border-radius:12px; font-weight:700;
}
.btn.primary{ background: linear-gradient(135deg, var(--brand), var(--accent)); }

/* ===== 研究（大きい画像） ===== */
.research-grid{
  display:grid; gap:18px;
  grid-template-columns: 1fr;
}
@media (min-width: 860px){
  .research-grid{ grid-template-columns: 1fr 1fr; }
}
.research-item{
  position:relative; border-radius:22px; overflow:hidden;
  box-shadow: var(--shadow);
}
.research-item img{
  width:100%; height:min(60vh, 520px);
  object-fit:cover; display:block;
  transition: transform .5s ease;
}
.research-item:hover img{ transform: scale(1.04) }
.research-item .overlay{
  position:absolute; inset:auto 0 0 0;
  background: linear-gradient(180deg, rgba(0,0,0,0) 0%, rgba(0,0,0,.55) 60%, rgba(0,0,0,.75) 100%);
  color:#ffffff; padding:18px;
}
.research-item .overlay h3{ margin:0 0 6px }
.research-item .overlay p{ margin:0; opacity:.95 }

/* ===== Timeline (受賞) ===== */
.timeline{
  list-style:none; margin:0; padding:0;
  display:grid; gap:18px;
}
.timeline li{
  display:grid; grid-template-columns: 24px 80px 1fr; align-items:start; gap:12px;
}
.timeline .dot{
  width:12px; height:12px; border-radius:50%;
  background:linear-gradient(135deg, var(--brand), var(--accent));
  margin-top:8px;
}
.timeline .dot2{
  width:12px; height:12px; border-radius:50%;
  background:linear-gradient(135deg, var(--brand-2), var(--accent-2));
  margin-top:8px;
}
.timeline .dot3{
  width:12px; height:12px; border-radius:50%;
  background:linear-gradient(135deg, var(--brand-3), var(--accent-3));
  margin-top:8px;
}
.timeline .time{ font-weight:700; color:#37474f }

/* ===== YouTube ===== */
.video-wrap{
  position:relative; width:100%; aspect-ratio: 16 / 9;
  border-radius:18px; overflow:hidden; box-shadow:var(--shadow);
  background:#000;
}
.video-wrap iframe{ width:100%; height:100%; border:0; display:block }
.center{ text-align:center; margin-top:12px }

/* ===== Link list ===== */
.link-list{
  list-style: none; display:grid; gap:10px; grid-template-columns: 1fr;
}
@media (min-width: 500px){
  .link-list{ grid-template-columns: 1fr 1fr; }
}
.link-list a{
  display:block; padding:12px 14px; border-radius:12px; background:#ffffff; box-shadow:var(--shadow);
  font-weight:700; text-decoration:none; color:#0d1720;
}
.link-list a:hover{ background:#f7fafc }

/* ===== Footer ===== */
.site-footer{
  border-top:1px solid #eee;
  padding:18px 0; color:#546e7a; font-size:.95rem;
}

/* ===== Mobile Nav ===== */
@media (max-width: 900px){
  .nav-toggle{ display:block }
  .menu{
    position:absolute; top:60px; right:16px; background:#fff; border:1px solid #eee;
    border-radius:12px; box-shadow:var(--shadow);
    padding:8px; flex-direction:column; gap:4px; display:none; min-width:180px;
  }
  .menu.open{ display:flex }
}