:root {
  --bg: #eef3f8;
  --card: rgba(255, 255, 255, 0.93);
  --text: #1f2937;
  --muted: #64748b;
  --line: #e5e7eb;
  --blue: #1d4ed8;
  --blue-dark: #0f172a;
  --cyan: #38bdf8;
  --shadow: 0 24px 60px rgba(15, 23, 42, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Helvetica Neue", Arial, "Hiragino Sans", "Yu Gothic", sans-serif;
  background:
    radial-gradient(circle at top left, rgba(59, 130, 246, 0.20), transparent 32%),
    radial-gradient(circle at top right, rgba(56, 189, 248, 0.14), transparent 28%),
    linear-gradient(180deg, #f7f9fc 0%, var(--bg) 100%);
  color: var(--text);
  line-height: 1.8;
}

a {
  color: #1d4ed8;
  text-decoration: none;
  font-weight: 700;
}

a:hover {
  text-decoration: underline;
}

.site-header {
  position: relative;
  color: #ffffff;
  text-align: center;
  padding: 5rem 1.5rem 5.5rem;
  background:
    radial-gradient(circle at 18% 20%, rgba(56, 189, 248, 0.32), transparent 24%),
    radial-gradient(circle at 80% 10%, rgba(129, 140, 248, 0.25), transparent 20%),
    linear-gradient(135deg, rgba(15, 23, 42, 0.98), rgba(30, 64, 175, 0.92));
  overflow: hidden;
}

.site-header::after {
  content: "";
  position: absolute;
  inset: auto -10% -90px -10%;
  height: 180px;
  background: #f7f9fc;
  border-radius: 50% 50% 0 0;
}

.header-inner {
  position: relative;
  z-index: 1;
  max-width: 960px;
  margin: 0 auto;
}

.eyebrow {
  margin: 0 0 0.6rem;
  color: #bfdbfe;
  font-size: 0.85rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  font-weight: 800;
}

.site-header h1 {
  margin: 0;
  font-size: clamp(2.6rem, 7vw, 5rem);
  letter-spacing: 0.08em;
  line-height: 1.1;
}

.subtitle {
  margin: 1rem 0 0;
  color: #e0f2fe;
  font-size: 1.25rem;
  font-weight: 700;
}

.lead {
  max-width: 780px;
  margin: 1rem auto 0;
  color: #dbeafe;
  font-size: 1.03rem;
}

.header-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 2rem;
}

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.75rem 1.25rem;
  border-radius: 999px;
  text-decoration: none;
  transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.primary-button {
  background: linear-gradient(135deg, #38bdf8, #2563eb);
  color: #ffffff;
  box-shadow: 0 16px 32px rgba(37, 99, 235, 0.35);
}

.secondary-button {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.28);
  backdrop-filter: blur(8px);
}

.primary-button:hover,
.secondary-button:hover {
  transform: translateY(-3px);
  text-decoration: none;
}

.menu-toggle {
  display: none;
  position: absolute;
  z-index: 3;
  top: 1rem;
  right: 1rem;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.16);
  color: #ffffff;
  font-size: 1.4rem;
}

.site-nav {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  justify-content: center;
  gap: 0.35rem;
  flex-wrap: wrap;
  padding: 0.7rem 1rem;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(148, 163, 184, 0.25);
  box-shadow: 0 12px 30px rgba(15, 23, 42, 0.06);
}

.site-nav a {
  display: inline-block;
  padding: 0.55rem 0.85rem;
  border-radius: 999px;
  color: #334155;
  font-size: 0.93rem;
}

.site-nav a:hover {
  background: #e0f2fe;
  color: #075985;
  text-decoration: none;
}

.container {
  width: min(1080px, calc(100% - 2rem));
  margin: -1.8rem auto 4rem;
  position: relative;
  z-index: 2;
}

.section-card {
  margin-bottom: 2rem;
  padding: 2rem;
  border-radius: 28px;
  background: var(--card);
  border: 1px solid rgba(148, 163, 184, 0.25);
  box-shadow: var(--shadow);
}

.section-title {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}

.section-title h2 {
  margin: 0;
  color: #0f172a;
  font-size: 1.9rem;
  letter-spacing: 0.03em;
}

.section-title p {
  margin: 0;
  color: var(--muted);
  font-weight: 800;
}

.about-container {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 2rem;
  align-items: center;
}

.profile-photo {
  width: 220px;
  height: 220px;
  object-fit: cover;
  border-radius: 32px;
  box-shadow: 0 18px 38px rgba(15, 23, 42, 0.16);
  border: 6px solid #ffffff;
}

.profile-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.75rem;
}

.profile-list li {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 1rem;
  padding: 0.85rem 1rem;
  border-radius: 16px;
  background: #f8fafc;
}

.profile-list span {
  color: #075985;
  font-weight: 800;
}

.profile-list small {
  color: var(--muted);
}

.news-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.85rem;
}

.news-list li {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 1rem;
  padding: 1rem 1.1rem;
  border-radius: 18px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  box-shadow: 0 10px 28px rgba(15, 23, 42, 0.05);
}

.news-list time {
  color: #1d4ed8;
  font-weight: 900;
}

.research-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 1.5rem;
  align-items: start;
}

.research-summary {
  padding: 1.3rem;
  border-radius: 22px;
  background: linear-gradient(135deg, #ffffff, #eff6ff);
  border: 1px solid rgba(37, 99, 235, 0.12);
}

.check-list {
  padding-left: 1.2rem;
  margin: 1rem 0;
}

.check-list li {
  margin-bottom: 0.45rem;
}

.detail-note {
  margin-bottom: 0;
  color: #475569;
  font-weight: 800;
}

.research-links {
  display: grid;
  gap: 1rem;
}

.research-button {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 104px;
  padding: 1.25rem;
  border-radius: 24px;
  background: linear-gradient(135deg, #1d4ed8, #38bdf8);
  color: #ffffff;
  text-decoration: none;
  box-shadow: 0 14px 30px rgba(37, 99, 235, 0.24);
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
}

.research-button span {
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: 0.05em;
}

.research-button small {
  margin-top: 0.2rem;
  color: #dbeafe;
  font-weight: 700;
}

.research-button:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(37, 99, 235, 0.34);
  text-decoration: none;
  background: linear-gradient(135deg, #1e3a8a, #0ea5e9);
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.info-box {
  padding: 1.3rem;
  border-radius: 22px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  box-shadow: 0 10px 28px rgba(15, 23, 42, 0.06);
}

.info-box.wide {
  grid-column: 1 / -1;
}

.info-box h3 {
  margin: 0 0 0.8rem;
  color: #0f172a;
  font-size: 1.15rem;
}

.info-box ul {
  margin: 0;
  padding-left: 1.2rem;
}

.link-box li {
  margin-bottom: 0.3rem;
}

.message-card p {
  font-size: 1.05rem;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.9rem;
}

.gallery img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 18px;
  box-shadow: 0 12px 28px rgba(15, 23, 42, 0.12);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.gallery img:hover {
  transform: translateY(-4px) scale(1.02);
  box-shadow: 0 20px 36px rgba(15, 23, 42, 0.18);
}

.site-footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--muted);
}

@media (max-width: 820px) {
  .menu-toggle {
    display: block;
  }

  .site-nav {
    display: none;
    position: sticky;
    top: 0;
    padding: 0.75rem;
  }

  .site-nav.active {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .container {
    width: min(100% - 1rem, 1080px);
  }

  .section-card {
    padding: 1.25rem;
    border-radius: 22px;
  }

  .section-title {
    display: block;
  }

  .section-title p {
    margin-top: 0.25rem;
  }

  .about-container,
  .research-grid,
  .info-grid {
    grid-template-columns: 1fr;
  }

  .profile-photo {
    width: 180px;
    height: 180px;
  }

  .news-list li,
  .profile-list li {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }

  .gallery {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  .site-header {
    padding: 4rem 1rem 4.5rem;
  }

  .header-actions {
    flex-direction: column;
  }

  .primary-button,
  .secondary-button {
    width: 100%;
  }

  .site-nav.active {
    grid-template-columns: 1fr;
  }

  .gallery {
    grid-template-columns: 1fr;
  }
}