/* ===================================================
   FONTS & BASE
   =================================================== */
body, h1, h2, h3, h4, h5, h6, small, .site-subtitle, .page__lead {
  font-family:
    "Helvetica Neue", Arial,
    "Hiragino Kaku Gothic ProN", "Hiragino Sans",
    "Yu Gothic Medium", "Yu Gothic", Meiryo,
    sans-serif;
  line-height: 1.8;
}

/* ===================================================
   LANGUAGE TOGGLE — visibility
   =================================================== */
.lang-en { display: none; }

[data-lang="en"] .lang-en { display: block; }
[data-lang="en"] .lang-ja { display: none; }

/* inline variants (for mixed-flow content) */
span.lang-en { display: none; }
[data-lang="en"] span.lang-en { display: inline; }
[data-lang="en"] span.lang-ja { display: none; }

/* ===================================================
   LANGUAGE TOGGLE BUTTON
   =================================================== */
.lang-toggle-btn {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 9999;
  background: #1a237e;
  color: #fff;
  border: none;
  border-radius: 50px;
  padding: 0.45rem 1.1rem;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  cursor: pointer;
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.35);
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
}
.lang-toggle-btn:hover {
  background: #283593;
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(0, 0, 0, 0.35);
}

/* ===================================================
   ACCENT VARIABLES (cascade)
   =================================================== */
:root {
  --accent: #1a237e;
  --accent-light: #e8eaf6;
  --text-muted: #666;
  --border-light: #e0e0e0;
  --card-shadow: 0 1px 4px rgba(0, 0, 0, 0.07);
  --radius: 6px;
}

/* ===================================================
   SECTION BLOCK (共通ラッパー)
   =================================================== */
.section-block {
  background: #fafafa;
  border-radius: var(--radius);
  border-left: 4px solid var(--accent);
  padding: 1.4rem 1.8rem;
  margin-bottom: 2rem;
}
.section-block h2 {
  margin-top: 0;
  color: var(--accent);
  font-size: 1.1rem;
  letter-spacing: 0.03em;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 0.5rem;
  margin-bottom: 1.2rem;
}
.section-block h3 {
  font-size: 0.95rem;
  color: #444;
  margin-top: 1.2rem;
  margin-bottom: 0.6rem;
}

/* ===================================================
   TIMELINE (経歴)
   =================================================== */
.timeline {
  position: relative;
  padding-left: 1.6rem;
  margin: 0;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 3px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: var(--border-light);
}
.timeline-item {
  position: relative;
  display: flex;
  gap: 1rem;
  margin-bottom: 1.2rem;
  align-items: flex-start;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: -1.47rem;
  top: 0.45rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid #fff;
  box-shadow: 0 0 0 2px var(--accent);
}
.timeline-period {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
  min-width: 8.5rem;
  padding-top: 0.1rem;
  flex-shrink: 0;
}
.timeline-content {
  flex: 1;
}
.timeline-title {
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 0.15rem;
}
.timeline-sub {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* group separator within timeline */
.timeline-divider {
  height: 1.2rem;
}

/* ===================================================
   AWARD LIST
   =================================================== */
.award-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.award-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 0.65rem 0;
  border-bottom: 1px solid #f0f0f0;
}
.award-item:last-child { border-bottom: none; }
.award-date {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
  min-width: 4.5rem;
  flex-shrink: 0;
  padding-top: 0.05rem;
}
.award-name {
  font-size: 0.9rem;
}
.award-name a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px dotted var(--accent);
}
.award-name a:hover { border-bottom-style: solid; }

/* ===================================================
   SIMPLE TAGS LIST (資格・学会など)
   =================================================== */
.tag-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.tag-list li {
  background: var(--accent-light);
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.25rem 0.75rem;
  border-radius: 50px;
}

/* ===================================================
   PUBLICATION CARDS
   =================================================== */
.pub-card {
  background: #fff;
  border: 1px solid var(--border-light);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  padding: 1rem 1.2rem;
  margin-bottom: 1rem;
  box-shadow: var(--card-shadow);
}
.pub-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 0.4rem;
}
.pub-year {
  background: var(--accent);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.1rem 0.5rem;
  border-radius: 3px;
  letter-spacing: 0.05em;
}
.pub-journal {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-style: italic;
}
.pub-title {
  font-weight: 700;
  font-size: 0.92rem;
  margin-bottom: 0.25rem;
  line-height: 1.5;
}
.pub-authors {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}
.pub-doi {
  display: inline-block;
  font-size: 0.78rem;
  color: var(--accent);
  text-decoration: none;
  border: 1px solid var(--accent);
  padding: 0.12rem 0.6rem;
  border-radius: 3px;
  transition: all 0.15s;
}
.pub-doi:hover {
  background: var(--accent);
  color: #fff;
}

/* ===================================================
   PRESENTATION CARDS
   =================================================== */
.pres-section {
  margin-bottom: 1.6rem;
}
.pres-section-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #555;
  border-bottom: 1px solid #eee;
  padding-bottom: 0.35rem;
  margin-bottom: 0.8rem;
}
.pres-card {
  background: #fff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  margin-bottom: 0.6rem;
  box-shadow: var(--card-shadow);
}
.pres-header {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  align-items: center;
  margin-bottom: 0.35rem;
}
.pres-tag {
  font-size: 0.68rem;
  font-weight: 700;
  padding: 0.1rem 0.45rem;
  border-radius: 3px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  flex-shrink: 0;
}
.tag-intl   { background: #e3f2fd; color: #1565c0; }
.tag-dom    { background: #e8f5e9; color: #2e7d32; }
.tag-ws     { background: #fff3e0; color: #e65100; }
.tag-oral   { background: #f3e5f5; color: #6a1b9a; }
.tag-poster { background: #fce4ec; color: #880e4f; }
.pres-venue {
  font-size: 0.78rem;
  color: #888;
  margin-left: auto;
}
.pres-title {
  font-size: 0.88rem;
  color: #333;
  line-height: 1.5;
}

/* ===================================================
   RESPONSIVE
   =================================================== */
@media (max-width: 600px) {
  .timeline-item { flex-direction: column; gap: 0.2rem; }
  .timeline-period { min-width: auto; }
  .pres-venue { margin-left: 0; width: 100%; margin-top: 0.2rem; }
  .lang-toggle-btn { bottom: 1rem; right: 1rem; }
}