:root {
  color-scheme: light dark;
  --accent: #54812d;
  --fg: #1a1a1a;
  --bg: #ffffff;
  --muted: #666666;
  --border: #dddddd;
  --font-body: "Hiragino Mincho ProN", "Yu Mincho", "Noto Serif JP", Georgia, "Times New Roman", serif;
  --font-heading: "Hiragino Mincho ProN", "Yu Mincho", "Noto Serif JP", Georgia, "Times New Roman", serif;
  --font-size: 17px;
  --line-height: 1.6;
  --max-width: 800px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --fg: #e6e6e6;
    --bg: #121212;
    --muted: #a0a0a0;
    --border: #333333;
    --accent: #9ad46a;
  }
}

/* Placed after the media block, not merged into it: an explicit dark choice must
   also win on a light OS, where the media query never matches. */
:root[data-theme="dark"] {
  --fg: #e6e6e6;
  --bg: #121212;
  --muted: #a0a0a0;
  --border: #333333;
  --accent: #9ad46a;
}

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

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

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 2rem 1.25rem;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: var(--font-size);
  line-height: var(--line-height);
}

h1,
h2,
h3 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.4;
}

h1 {
  margin: 0;
  font-size: 1.7em;
}

h2 {
  margin: 2.5rem 0 1rem;
  font-size: 1.2em;
}

h3 {
  margin: 1.75rem 0 0.5rem;
  font-size: 1em;
  color: var(--muted);
}

html[data-heading-style="underline"] h2 {
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.3em;
}

html[data-heading-style="bar"] h2 {
  border-left: 4px solid var(--accent);
  padding-left: 0.6em;
}

html[data-heading-style="none"] h2 {
  border: 0;
  padding: 0;
}

p {
  margin: 0 0 1em;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.header-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
}

#lang-toggle {
  flex: none;
  padding: 0.3em 0.9em;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--fg);
  font: inherit;
  font-size: 0.8em;
  cursor: pointer;
}

#lang-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.affiliation {
  margin: 0.5em 0 1em;
  color: var(--muted);
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4em 1.1em;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.9em;
  overflow-wrap: anywhere;
}

.keywords {
  color: var(--muted);
  font-size: 0.9em;
}

.timeline {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 0.4em 1.25em;
  margin: 0;
}

.timeline dt {
  color: var(--muted);
  font-size: 0.9em;
  white-space: nowrap;
}

.timeline dd {
  margin: 0;
}

.pub-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.pub-list li {
  margin-bottom: 1em;
  overflow-wrap: anywhere;
}

.pub-venue {
  color: var(--muted);
}

.pub-links {
  font-size: 0.85em;
}

footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.85em;
}

footer p {
  margin: 0 0 0.3em;
}