/* ==========================================================
   Base
   ========================================================== */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: #ffffff;
  color: #1f2937;
  font-family: Charter, "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
  font-size: 16px;
  line-height: 1.35;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #166534;
  font-weight: 600;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

h1 {
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1.15;
  color: #111827;
  margin: 0 0 0.75rem;
}

h2 {
  font-size: 1.2rem;
  font-weight: 600;
  color: #111827;
  margin: 1.5rem 0 0.5rem;
  padding-bottom: 0.2rem;
  border-bottom: 1px solid #b4bac3;
}

h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: #111827;
  margin: 1.1rem 0 0.3rem;
}

p {
  margin: 0 0 0.6rem;
}

strong {
  font-weight: 600;
  color: #111827;
}

.muted {
  color: #6b7280;
}

/* Page width */
.wrap {
  max-width: 62rem;
  margin: 0 auto;
  padding: 0 1.25rem;
}

main.wrap {
  padding-top: 1.5rem;
  padding-bottom: 1rem;
}

/* ==========================================================
   Header and footer
   ========================================================== */
.site-header {
  border-bottom: 1px solid #e5e7eb;
}

.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem 1.5rem;
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}

.site-name {
  font-size: 1.1rem;
  font-weight: 600;
  color: #111827;
}

.site-header nav {
  display: flex;
  gap: 1.5rem;
}

/* Menu links use the same regular weight and color as the page text */
.site-header nav a {
  color: #1f2937;
  font-weight: 400;
}

.site-footer {
  text-align: center;
  font-size: 0.85rem;
  color: #6b7280;
  padding: 2rem 0 1.5rem;
}

/* ==========================================================
   Markdown content (home page body, page intros)
   ========================================================== */
.content ul {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
}

.content ul li {
  margin-bottom: 0.45rem;
}

.intro {
  margin-bottom: 1rem;
}

/* ==========================================================
   Home page
   ========================================================== */
/* The photo is exactly as tall as the text block beside it */
.profile {
  display: flex;
  gap: 1.75rem;
  align-items: stretch;
  margin-bottom: 1.25rem;
}

.profile-photo {
  position: relative;
  width: 210px;
  flex-shrink: 0;
}

.profile-photo img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 4px;
}

.profile h1 {
  margin: 0;
  font-size: 1.15rem;
  line-height: 1.35;
}

.profile p {
  margin: 0 0 0.75rem;
}

.profile .title {
  font-style: italic;
}

.profile-links {
  margin-top: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.8rem;
  font-size: 0.95rem;
}

/* Awards in the Education section */
.award {
  color: #9a3412;
}

.award::before {
  content: "★ ";
}

@media (max-width: 640px) {
  .profile {
    flex-direction: column;
    gap: 1rem;
  }

  .profile-photo {
    height: 230px;
  }
}

/* ==========================================================
   Research and INFORMS pages
   ========================================================== */
/* The photo is exactly as tall as the intro text beside it */
.research-intro {
  display: flex;
  gap: 1.75rem;
  align-items: stretch;
  margin-bottom: 0.5rem;
}

.research-photo {
  position: relative;
  width: 170px;
  flex-shrink: 0;
}

.research-photo img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  border-radius: 4px;
}

.research-intro .content p:last-child {
  margin-bottom: 0;
}

@media (max-width: 640px) {
  .research-intro {
    flex-direction: column;
  }

  .research-photo {
    height: 230px;
  }
}

.areas h3 {
  font-size: 1.05rem;
  margin-top: 1.4rem;
}

.areas h3:first-child {
  margin-top: 0;
}

figure {
  margin: 0.75rem 0 1rem;
}

/* All figures share the same display height */
figure img {
  display: block;
  width: auto;
  height: auto;
  max-width: min(100%, 500px);
  max-height: 250px;
  margin: 0 auto;
}

figcaption {
  max-width: 500px;
  margin: 0.5rem auto 0;
  font-size: 0.85rem;
  color: #6b7280;
  line-height: 1.35;
}

.paper-title {
  font-weight: 600;
  color: #111827;
}

.paper-authors {
  font-size: 0.95rem;
  color: #4b5563;
}

.paper-links {
  font-size: 0.9rem;
}

.paper-links a {
  margin-right: 0.9rem;
}

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

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

/* Inline markdown (author lists) should not add paragraph spacing */
.ref-list p,
.paper-authors p {
  display: inline;
  margin: 0;
}

.eyebrow {
  margin: 0 0 0.5rem;
  color: #166534;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* ==========================================================
   Tables (Teaching page)
   ========================================================== */
.content table {
  border-collapse: collapse;
  margin: 0.25rem 0 1rem;
}

.content th,
.content td {
  text-align: left;
  vertical-align: top;
  padding: 0.2rem 1.5rem 0.2rem 0;
  border-bottom: 1px solid #e5e7eb;
}

.content th {
  font-weight: 600;
  color: #111827;
  border-bottom: 1px solid #b4bac3;
}

/* ==========================================================
   Diary (travel) page
   ========================================================== */
.travel h1 {
  text-align: center;
  margin-bottom: 0.25rem;
}

.travel > .muted {
  text-align: center;
  margin-bottom: 2rem;
}

.travel-entry {
  margin-bottom: 2rem;
}

.travel-entry h2 {
  border-bottom: none;
  padding-bottom: 0;
  margin: 0 0 0.25rem;
  font-size: 1.15rem;
}

.travel-entry p {
  color: #555;
  font-size: 0.9rem;
  margin-bottom: 0.75rem;
}

.swiper-container {
  position: relative;
  overflow: hidden;
  padding-bottom: 1.75rem;
}

.swiper-slide {
  display: flex;
  justify-content: center;
}

.gallery-img {
  width: 100%;
  max-width: 260px;
  height: 196px;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid #ddd;
  cursor: pointer;
}

.swiper-button-prev,
.swiper-button-next {
  width: 36px !important;
  height: 36px !important;
  background: rgba(0, 0, 0, 0.6);
  border-radius: 50%;
  color: #fff !important;
  margin-top: -32px !important;
}

.swiper-button-prev:after,
.swiper-button-next:after {
  font-size: 16px !important;
  font-weight: bold;
}

.swiper-pagination {
  bottom: 0 !important;
}

.swiper-pagination-bullet-active {
  background: #111827 !important;
}

#lightbox-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.8);
  align-items: center;
  justify-content: center;
  z-index: 100;
}

#lightbox-img {
  max-width: 90%;
  max-height: 90%;
  border-radius: 8px;
}