:root,
[data-theme="light"] {
  --bg: #ffffff;
  --bg-alt: #f6f8f7;
  --text: #182424;
  --text-secondary: #536564;
  --accent: #0c7c72;
  --accent-hover: #095f58;
  --border: #dce5e3;
  --card-bg: #ffffff;
  --nav-bg: rgba(255, 255, 255, 0.92);
  --shadow: 0 1px 4px rgba(24, 36, 36, 0.08);
}

[data-theme="dark"] {
  --bg: #101918;
  --bg-alt: #172322;
  --text: #e7eeee;
  --text-secondary: #a6b9b7;
  --accent: #39c6b8;
  --accent-hover: #6ee0d5;
  --border: #2b403e;
  --card-bg: #14201f;
  --nav-bg: rgba(16, 25, 24, 0.92);
  --shadow: 0 1px 4px rgba(0, 0, 0, 0.25);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 5rem;
}

body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.7;
}

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

a:hover {
  color: var(--accent-hover);
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  font-family: Georgia, "Times New Roman", serif;
  line-height: 1.3;
  letter-spacing: 0;
}

.container {
  width: min(860px, calc(100% - 3rem));
  margin: 0 auto;
}

.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  border-bottom: 1px solid var(--border);
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 3.5rem;
  width: min(860px, calc(100% - 3rem));
  margin: 0 auto;
}

.nav-logo {
  color: var(--text);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.1rem;
  font-weight: 700;
}

.nav-links {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.88rem;
}

.nav-links a.active,
.nav-links a:hover {
  color: var(--accent);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-secondary);
  background: transparent;
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

[data-theme="light"] .icon-moon {
  display: none;
}

[data-theme="dark"] .icon-sun {
  display: none;
}

.nav-menu-btn {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 4px;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.nav-menu-btn span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text);
  transition: opacity 0.2s, transform 0.2s;
}

.nav-menu-btn.open span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-menu-btn.open span:nth-child(2) {
  opacity: 0;
}

.nav-menu-btn.open span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.hero {
  padding: 7rem 0 4rem;
}

.hero h1 {
  margin-bottom: 0.25rem;
  font-size: clamp(2rem, 6vw, 3.2rem);
}

.subtitle {
  margin-bottom: 1rem;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.bio {
  max-width: 760px;
  margin-bottom: 1.25rem;
  color: var(--text-secondary);
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0.46rem 1rem;
  border: 1px solid var(--accent);
  border-radius: 8px;
  background: var(--accent);
  color: #ffffff;
  font-size: 0.88rem;
  font-weight: 600;
}

.btn:hover {
  border-color: var(--accent-hover);
  background: var(--accent-hover);
  color: #ffffff;
}

.btn-outline {
  background: transparent;
  color: var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: #ffffff;
}

.section {
  padding: 4rem 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section h2 {
  display: inline-block;
  margin-bottom: 1.25rem;
  padding-bottom: 0.45rem;
  border-bottom: 2px solid var(--accent);
  font-size: 1.6rem;
}

.section-note {
  max-width: 680px;
  margin-bottom: 1.4rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

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

.research-item,
.timeline-item {
  padding-left: 1rem;
  border-left: 3px solid var(--border);
}

.research-item h3,
.timeline-item h3 {
  margin-bottom: 0.25rem;
  font-size: 1.05rem;
}

.research-item p,
.timeline-item p {
  margin-bottom: 0;
  color: var(--text-secondary);
}

.timeline-list {
  display: grid;
  gap: 1rem;
}

.timeline-item {
  display: grid;
  grid-template-columns: 145px minmax(0, 1fr);
  gap: 1rem;
}

.timeline-date {
  color: var(--accent);
  font-size: 0.88rem;
  font-weight: 700;
}

.timeline-item-no-date {
  grid-template-columns: 1fr;
}

.timeline-place {
  font-weight: 600;
}

.pub-year {
  margin: 1.55rem 0 0.75rem;
  color: var(--accent);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.22rem;
  font-weight: 700;
}

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 1.15rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.pub-item {
  display: flex;
  flex-direction: column;
  gap: 0.18rem;
  padding-left: 1rem;
  border-left: 3px solid var(--border);
}

.pub-item:hover {
  border-left-color: var(--accent);
}

.pub-title {
  color: var(--text);
  font-size: 0.98rem;
  font-weight: 600;
}

.pub-title a {
  color: inherit;
}

.pub-title a:hover {
  color: var(--accent);
}

.pub-authors,
.pub-venue {
  color: var(--text-secondary);
  font-size: 0.88rem;
}

.pub-venue {
  font-style: italic;
}

.author-me,
.venue-rank {
  color: var(--accent);
  font-weight: 700;
}

.pub-links {
  margin-top: 0.1rem;
  color: var(--text-secondary);
  font-size: 0.86rem;
}

.contact-list {
  display: grid;
  gap: 0.7rem;
}

.contact-item {
  color: var(--text-secondary);
}

.contact-item strong {
  color: var(--text);
}

.back-to-top {
  position: fixed;
  right: 2rem;
  bottom: 2rem;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--card-bg);
  color: var(--text-secondary);
  box-shadow: var(--shadow);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, color 0.2s, border-color 0.2s;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.footer {
  padding: 2rem 0;
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.82rem;
  text-align: center;
}

.footer p {
  margin: 0;
}

@media (max-width: 740px) {
  .nav-links {
    position: absolute;
    top: 3.5rem;
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
  }

  .nav-links.open {
    display: flex;
  }

  .nav-menu-btn {
    display: flex;
  }

  .hero {
    padding-top: 6rem;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }

  .container,
  .nav-inner {
    width: min(100% - 2rem, 860px);
  }
}