/* 2026年度 技術部報告会 共通スタイル */
:root{
  --navy:#2f6fb0;
  --navy-deep:#1f4e85;
  --accent:#6bb6e8;
  --accent-light:#bfe2f7;
  --tx2:#2c3e50;
  --white:#ffffff;
  --bg:#eef1f6;
  --text:#28303b;
  --muted:#657085;
  --line:#e2e7ee;
  --radius:16px;
  --shadow:0 6px 20px rgba(15,35,65,0.08);
  --shadow-hover:0 16px 32px rgba(15,60,120,0.18);
  --maxw:1080px;
}
*{box-sizing:border-box;}
html,body{
  margin:0;
  padding:0;
  background:var(--bg);
  color:var(--text);
  font-family:"Hiragino Kaku Gothic ProN","Hiragino Sans","Yu Gothic","MS PGothic",Meiryo,sans-serif;
  line-height:1.85;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;}
img{max-width:100%;}

/* ===== ヘッダー：大学名・部署名 + YNUロゴ ===== */
.site-header{
  display:flex;
  align-items:flex-start;
  justify-content:space-between;
  max-width:var(--maxw);
  margin:0 auto;
  padding:18px 20px 10px;
}
.site-header .univ-block .univ{
  margin:0;
  font-size:0.8rem;
  letter-spacing:.04em;
  color:var(--muted);
}
.site-header .univ-block .dept{
  margin:3px 0 0;
  font-size:1.55rem;
  font-weight:700;
  color:var(--tx2);
  letter-spacing:.02em;
}
.site-header img{
  height:26px;
  display:block;
  margin-top:6px;
}

/* ===== ヒーロー（タイトルバー） ===== */
.title-bar{
  position:relative;
  background:
    radial-gradient(1200px 260px at 15% -60%, rgba(255,255,255,.18), transparent 60%),
    linear-gradient(120deg, var(--navy-deep) 0%, var(--navy) 55%, var(--accent) 100%);
  padding:38px 20px 34px;
  overflow:hidden;
}
.title-bar::after{
  content:"";
  position:absolute;
  inset:auto 0 0 0;
  height:4px;
  background:linear-gradient(to right, var(--navy) 0%, var(--accent) 50%, var(--accent-light) 100%);
}
.title-bar h1{
  margin:0 auto;
  max-width:var(--maxw);
  color:#fff;
  font-size:clamp(1.15rem,2.6vw,1.85rem);
  font-weight:700;
  letter-spacing:.02em;
  line-height:1.5;
}
.title-bar-sub{
  margin:12px auto 0;
  max-width:var(--maxw);
  display:flex;
  flex-wrap:wrap;
  gap:10px 20px;
  color:#dce8f7;
  font-size:0.92rem;
}
.title-bar-sub span{
  display:inline-flex;
  align-items:center;
  gap:6px;
}
.title-bar-sub span::before{
  content:"";
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--accent-light);
  display:inline-block;
}

.wrap{
  max-width:var(--maxw);
  margin:0 auto;
  padding:36px 20px 60px;
}

/* ===== カード共通 ===== */
.card{
  background:#fff;
  border-radius:var(--radius);
  box-shadow:var(--shadow);
  padding:30px 34px;
  margin-bottom:32px;
  border-top:4px solid var(--accent);
}
.card h2{
  color:var(--tx2);
  margin:0 0 18px;
  font-size:1.3rem;
  display:flex;
  align-items:center;
  gap:10px;
}
.card h2::before{
  content:"";
  width:10px;
  height:10px;
  border-radius:2px;
  background:var(--accent);
  display:inline-block;
  transform:rotate(45deg);
}
.card .lead{
  margin:0 0 26px;
  text-align:justify;
  color:var(--text);
}

/* ===== 開催情報リスト ===== */
.info-list{
  margin:0;
  display:flex;
  flex-direction:column;
}
.info-row{
  display:grid;
  grid-template-columns:140px 1fr;
  gap:6px 20px;
  padding:16px 0;
  border-top:1px solid var(--line);
}
.info-row:first-child{border-top:none;}
.info-row dt{
  font-weight:700;
  color:var(--tx2);
  margin:0;
}
.info-row dd{
  margin:0;
}
@media (max-width:560px){
  .info-row{grid-template-columns:1fr;}
}
.info-sublist{
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  flex-direction:column;
  gap:8px;
}
.info-sublist li{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
}
.tag{
  display:inline-block;
  flex-shrink:0;
  background:#e7f0fb;
  color:var(--navy);
  border:1px solid #cfe1f5;
  border-radius:999px;
  padding:2px 12px;
  font-size:0.82rem;
  font-weight:700;
}

/* ===== 4つのリンクへのナビゲーション ===== */
.nav-section-title{
  margin:0 0 18px;
  color:var(--tx2);
  font-size:1.3rem;
}
.nav-grid{
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:20px;
}
@media (max-width:640px){
  .nav-grid{grid-template-columns:1fr;}
}
.nav-card{
  position:relative;
  display:flex;
  align-items:center;
  gap:18px;
  padding:24px 26px;
  border-radius:var(--radius);
  background:#fff;
  border:1px solid var(--line);
  text-decoration:none;
  color:var(--tx2);
  box-shadow:var(--shadow);
  transition:transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.nav-card:hover{
  transform:translateY(-4px);
  box-shadow:var(--shadow-hover);
  border-color:var(--accent);
}
.nav-icon{
  flex-shrink:0;
  width:52px;
  height:52px;
  border-radius:50%;
  display:flex;
  align-items:center;
  justify-content:center;
  background:linear-gradient(135deg, var(--navy) 0%, var(--accent) 100%);
  color:#fff;
}
.nav-icon svg{width:26px;height:26px;stroke:currentColor;fill:none;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;}
.nav-text{display:flex;flex-direction:column;gap:2px;}
.nav-label{font-weight:700;font-size:1.05rem;}
.nav-desc{font-size:0.82rem;color:var(--muted);font-weight:400;}
.nav-arrow{
  position:absolute;
  right:20px;
  top:50%;
  transform:translateY(-50%);
  color:var(--accent);
  font-size:1.2rem;
  transition:transform .18s ease;
}
.nav-card:hover .nav-arrow{transform:translateY(-50%) translateX(4px);}

/* ===== サイト外へのリンク ===== */
.ext-link{
  color:var(--navy);
  text-decoration:underline;
  text-underline-offset:2px;
}
.ext-link:hover{color:var(--accent);}
.ext-icon{
  display:inline-flex;
  vertical-align:middle;
  margin-left:4px;
  width:0.8em;
  height:0.8em;
}
.ext-icon svg{
  width:100%;
  height:100%;
  fill:none;
  stroke:currentColor;
  stroke-width:2;
  stroke-linecap:round;
  stroke-linejoin:round;
}
.sr-only{
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip:rect(0,0,0,0);
  white-space:nowrap;
  border:0;
}

/* ===== フッター ===== */
.footer-bar{
  background:linear-gradient(120deg, var(--navy-deep) 0%, var(--navy) 100%);
  padding:22px 20px;
  text-align:center;
  color:#eaf1fb;
}
.footer-bar .footer-dept{
  margin:0;
  font-weight:700;
  letter-spacing:.05em;
}
.footer-bar .footer-copy{
  margin:6px 0 0;
  font-size:0.78rem;
  color:#d3e6f7;
}

/* ===== 挨拶ページ用 ===== */
.back-link{
  display:inline-flex;
  align-items:center;
  gap:8px;
  margin-bottom:22px;
  padding:10px 22px 10px 18px;
  border-radius:999px;
  background:#fff;
  border:1px solid var(--line);
  color:var(--navy);
  text-decoration:none;
  font-size:0.92rem;
  font-weight:700;
  box-shadow:var(--shadow);
  transition:transform .15s ease, box-shadow .15s ease, border-color .15s ease;
}
.back-link:hover{
  transform:translateY(-2px);
  box-shadow:var(--shadow-hover);
  border-color:var(--accent);
}
.back-link svg{
  width:16px;
  height:16px;
  flex-shrink:0;
  fill:none;
  stroke:currentColor;
  stroke-width:2.2;
  stroke-linecap:round;
  stroke-linejoin:round;
}
.page-footer-nav{
  text-align:center;
  margin:44px 0 0;
  padding-top:30px;
  border-top:1px solid var(--line);
}
.page-footer-nav .back-link{margin-bottom:0;}
.speaker{
  font-size:1.1rem;
  font-weight:700;
  color:var(--tx2);
  margin:0 0 24px;
  padding-bottom:16px;
  border-bottom:1px solid var(--line);
}
.msg-body p{
  text-align:justify;
  margin:0 0 1.1em;
}

/* ===== 利用条件・免責事項ページ用 ===== */
.notice{
  display:flex;
  gap:12px;
  align-items:flex-start;
  background:#fdeceb;
  border:1px solid #f3b8b4;
  border-radius:12px;
  padding:16px 20px;
  margin:0 0 26px;
  color:#c0392b;
  font-weight:700;
}
.notice-icon{
  flex-shrink:0;
  width:22px;
  height:22px;
  margin-top:2px;
}
.notice-icon svg{width:100%;height:100%;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;}
.notice p{margin:0 0 4px;}
.notice p:last-child{margin-bottom:0;}

.terms-list{
  margin:0;
  padding-left:1.4em;
  display:flex;
  flex-direction:column;
  gap:14px;
}
.terms-list li{
  text-align:justify;
  padding-left:4px;
}

.agree-actions{
  text-align:center;
  margin-top:36px;
}
.btn-agree{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:16px 42px;
  border-radius:999px;
  background:linear-gradient(135deg, var(--navy) 0%, var(--accent) 100%);
  color:#fff;
  font-size:1.1rem;
  font-weight:700;
  text-decoration:none;
  box-shadow:var(--shadow-hover);
  transition:transform .18s ease, box-shadow .18s ease, filter .18s ease;
}
.btn-agree:hover{
  transform:translateY(-3px);
  filter:brightness(1.08);
}
.btn-agree svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;}

/* ===== ポスター掲示ページ用 ===== */
.poster-grid{
  display:grid;
  grid-template-columns:1fr;
  gap:28px;
}
.poster-item{
  background:#fff;
  border-radius:var(--radius);
  box-shadow:var(--shadow);
  padding:24px;
  border-top:4px solid var(--accent);
}
.poster-item h3{
  color:var(--tx2);
  margin:0 0 4px;
}
.poster-item .authors{
  color:var(--muted);
  font-size:0.9rem;
  margin:0 0 16px;
}
.poster-item object{
  display:block;
  width:100%;
  height:100%;
  pointer-events:none;
  background:#f8f9fb;
}
.poster-frame{
  display:block;
  width:100%;
  max-width:640px;
  aspect-ratio:210/297;
  margin:0 auto;
  border:1px solid var(--line);
  border-radius:8px;
  overflow:hidden;
  cursor:pointer;
  transition:border-color .15s ease, box-shadow .15s ease;
}
.poster-frame:hover,
.poster-frame:focus-visible{
  border-color:var(--accent);
  box-shadow:0 0 0 3px rgba(107,182,232,0.3);
}
.poster-item .fallback{
  padding:16px;
  color:var(--muted);
}
.poster-item .open-link{
  display:inline-block;
  margin-top:12px;
  color:var(--navy);
  font-weight:700;
  text-decoration:none;
}
.poster-item .open-link:hover{text-decoration:underline;}