/* Root & base */
:root {
  --text: #1f2a3d;
  --muted: #5c6574;
  --accent: #1e88e5;
  --bg: #ffffff;
  --surface: #f6f8fb;
  --border: #e3e8ef;
  --shadow: 0 12px 30px rgba(17, 24, 39, 0.08);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  color: var(--text);
  margin: 0 0 0.5rem;
  line-height: 1.3;
}

p {
  margin: 0 0 1rem;
  color: var(--muted);
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  padding-left: 1.2rem;
  margin: 0.5rem 0 1rem;
}

.container {
  width: min(1100px, 92vw);
  margin: 0 auto;
}

.section {
  padding: 5rem 0;
}

.section h2 {
  font-size: 1.9rem;
  letter-spacing: -0.01em;
}

.section-lead {
  max-width: 760px;
}

.text-link {
  color: var(--accent);
  font-weight: 600;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.4rem;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  border: none;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
  box-shadow: 0 10px 25px rgba(30, 136, 229, 0.25);
}

.button:hover {
  transform: translateY(-1px);
  box-shadow: 0 12px 30px rgba(30, 136, 229, 0.3);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 800;
  letter-spacing: 0.01em;
}

.brand-name {
  display: inline-flex;
  align-items: center;
  line-height: 1.1;
  font-size: 2.1rem;
  transform: translateY(15px);
}

.brand-mark {
  width: 60px;
  height: 60px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: transparent;
  overflow: hidden;
}

.brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  border-radius: 10px;
}

.main-nav ul {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 0;
  padding: 0;
}

.main-nav a {
  padding: 0.6rem 0.9rem;
  border-radius: 999px;
  font-weight: 600;
  color: var(--muted);
  transition: color 0.15s ease, background 0.15s ease;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--accent);
  background: rgba(30, 136, 229, 0.12);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #fff;
  padding: 10px;
  flex-direction: column;
  justify-content: space-between;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: var(--text);
  border-radius: 4px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

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

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

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

/* Hero */
.hero {
  padding: 6rem 0 4rem;
  background: linear-gradient(135deg, #f7fbff 0%, #ffffff 60%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.hero-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: start;
  gap: 1.5rem;
}

.hero-text {
  min-width: 320px;
}

.eyebrow {
  text-transform: uppercase;
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  color: var(--accent);
  font-weight: 700;
}

.hero h1 {
  font-size: 2.8rem;
}

.tagline {
  font-size: 1.1rem;
  color: var(--text);
  margin-bottom: 0.6rem;
}

.bio {
  max-width: 720px;
  margin-bottom: 0.9rem;
}

.lists {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 1.5rem;
}

.info-box {
  margin-top: 1.5rem;
  padding: 1.25rem 1.4rem;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: #fff;
  box-shadow: var(--shadow);
}

.interest-box,
.news-box {
  margin-top: 1.25rem;
}

.news-box {
  max-height: 220px;
  overflow: auto;
}

.bullet-list,
.news-list {
  margin: 0.5rem 0 0;
  padding-left: 1.1rem;
  color: var(--muted);
}

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

.headshot-frame {
  width: 320px;
  height: 320px;
  border-radius: 18px;
  padding: 8px;
  background: #fff;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.headshot-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 12px;
}

.headshot-small {
  width: 320px;
  height: 320px;
}

@media (max-width: 860px) {
  .hero-header {
    grid-template-columns: 1fr;
    justify-items: start;
  }

  .headshot-small {
    width: 280px;
    height: 280px;
  }
}

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 1.75rem;
}

.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.4rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.card-header {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  background: rgba(30, 136, 229, 0.1);
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 700;
}

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

/* Publications */
.pub-group {
  margin-top: 1.5rem;
}

.pub-list {
  list-style: none;
  padding: 0;
  margin: 0.75rem 0 0;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.pub-list li {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: #fff;
  box-shadow: var(--shadow);
}

.pub-list .authors {
  display: block;
  color: var(--text);
  font-weight: 600;
}

.pub-list .title {
  display: block;
  margin: 0.25rem 0;
}

.pub-list .venue {
  display: block;
  color: var(--muted);
  margin-bottom: 0.35rem;
}

/* Talks & Posters */
.two-col {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.4rem;
  margin-top: 1rem;
}

.simple-list {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 0;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.simple-list li {
  padding: 1rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #fff;
  box-shadow: var(--shadow);
}

.item-title {
  display: block;
  color: var(--text);
  font-weight: 700;
}

.item-meta {
  display: block;
  color: var(--muted);
  margin: 0.25rem 0 0.35rem;
}

/* Teaching & Service */
.bullet-list {
  list-style: disc;
}

/* Contact */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
  margin-top: 0.75rem;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.icon-link {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.6rem 0.8rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  transition: background 0.15s ease, transform 0.15s ease;
}

.icon-link:hover {
  background: rgba(30, 136, 229, 0.08);
  transform: translateY(-1px);
}

.icon-link svg {
  width: 20px;
  height: 20px;
  fill: var(--accent);
}

/* Footer */
.site-footer {
  padding: 1.5rem 0 2rem;
  border-top: 1px solid var(--border);
  background: #fff;
  text-align: center;
  color: var(--muted);
}

/* Responsive */
@media (max-width: 960px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: left;
  }

  .hero-headshot {
    justify-content: flex-start;
  }
}

@media (max-width: 780px) {
  .main-nav {
    position: absolute;
    top: 64px;
    right: 4vw;
    left: 4vw;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 14px;
    box-shadow: var(--shadow);
    display: none;
  }

  .main-nav.open {
    display: block;
  }

  .main-nav ul {
    flex-direction: column;
    align-items: stretch;
    padding: 0.5rem;
  }

  .main-nav a {
    width: 100%;
  }

  .nav-toggle {
    display: flex;
  }
}