/* Research overview, topic pages, and shared Research dropdown. */
.research-area-strip {
  position: sticky;
  z-index: 8;
  top: 108px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: #fbfaf7;
  border: 1px solid #d8ddd9;
}

.research-area-strip a {
  min-height: 62px;
  padding: 14px 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #68737c;
  border-right: 1px solid #d8ddd9;
  font-size: 11px;
  font-weight: 800;
  line-height: 1.35;
}

.research-area-strip a:last-child { border-right: 0; }
.research-area-strip a:hover,
.research-area-strip a:focus-visible,
.research-area-strip a[aria-current="page"] {
  color: #fff;
  background: #087d81;
  outline: none;
}

.research-overview-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.research-overview-card {
  min-height: 500px;
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid #d8ddd9;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.research-overview-card:hover,
.research-overview-card:focus-visible {
  border-color: #08a6aa;
  transform: translateY(-5px);
  outline: none;
}

.research-overview-card img {
  width: 100%;
  height: 270px;
  object-fit: cover;
}

.research-overview-card div {
  padding: 30px;
}

.research-overview-card span,
.research-topic-index {
  color: #087d81;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 10px;
  font-weight: 900;
}

.research-overview-card h2 {
  margin: 14px 0 16px;
  font: 400 clamp(30px, 3vw, 43px)/1.08 Georgia, serif;
}

.research-overview-card p {
  color: #68737c;
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
}

.research-area-intro {
  max-width: 760px;
  margin-bottom: 58px;
}

.research-area-intro p {
  color: #68737c;
  font-size: 16px;
  line-height: 1.75;
}

.research-topic-list {
  display: grid;
  gap: 96px;
}

.research-topic {
  padding-bottom: 92px;
  display: grid;
  grid-template-columns: 0.72fr 1.28fr;
  align-items: center;
  gap: 70px;
  border-bottom: 1px solid #d8ddd9;
  scroll-margin-top: 190px;
}

.research-topic:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.research-topic-copy h2 {
  margin: 16px 0 24px;
  font: 400 clamp(36px, 4vw, 55px)/1.06 Georgia, serif;
  letter-spacing: -0.035em;
}

.research-topic-copy p {
  color: #68737c;
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.78;
}

.research-topic .area-carousel {
  height: 430px;
  margin: 0;
  background: #e8ebe7;
  border: 1px solid #d8ddd9;
  box-shadow: 0 26px 60px rgba(7, 26, 47, 0.12);
}

.research-topic .carousel-slide img {
  object-fit: contain;
  background: #fff;
}

.research-topic:nth-child(even) .research-topic-copy { order: 2; }
.research-topic:nth-child(even) .research-topic-carousel { order: 1; }

.research-chronology {
  margin: 0 0 42px;
  color: #68737c;
  font-size: 12px;
  font-style: italic;
}

.nav-dropdown {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 70px;
}

.nav-dropdown-trigger {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.nav-dropdown-trigger::after {
  content: "⌄";
  color: #64d8da;
  font-size: 12px;
}

.nav-dropdown-menu {
  position: absolute;
  z-index: 40;
  top: calc(100% - 2px);
  left: 50%;
  width: 330px;
  padding: 12px;
  display: none;
  background: #fff;
  color: #071a2f;
  border: 1px solid #d8ddd9;
  box-shadow: 0 22px 55px rgba(4, 17, 31, 0.24);
  transform: translateX(-50%);
}

.nav-dropdown-menu::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -13px;
  height: 13px;
}

.nav-dropdown-menu a {
  padding: 12px 13px;
  display: block;
  border-bottom: 1px solid #e5e8e4;
  font-size: 12px;
  font-weight: 750;
  line-height: 1.35;
}

.nav-dropdown-menu a:last-child { border-bottom: 0; }
.nav-dropdown-menu a:hover,
.nav-dropdown-menu a:focus-visible {
  color: #087d81;
  background: #f5f1e8;
  outline: none;
}

.nav-dropdown:hover .nav-dropdown-menu,
.nav-dropdown:focus-within .nav-dropdown-menu {
  display: grid;
}

.mobile-research-links {
  padding: 5px 0 8px 15px;
  display: grid;
  background: #f5f1e8;
}

.mobile-menu .mobile-research-links a {
  padding: 10px 11px;
  color: #52606a;
  font-size: 11px;
}

@media (max-width: 1000px) {
  .research-topic {
    grid-template-columns: 1fr;
    gap: 35px;
  }

  .research-topic:nth-child(even) .research-topic-copy,
  .research-topic:nth-child(even) .research-topic-carousel {
    order: initial;
  }

  .research-topic .area-carousel {
    height: 460px;
  }
}

@media (max-width: 760px) {
  .research-area-strip {
    top: 110px;
    display: flex;
    overflow-x: auto;
  }

  .research-area-strip a {
    min-width: 190px;
  }

  .research-overview-grid {
    grid-template-columns: 1fr;
  }

  .research-overview-card {
    min-height: auto;
  }

  .research-overview-card img {
    height: 230px;
  }

  .research-topic-list {
    gap: 68px;
  }

  .research-topic {
    padding-bottom: 65px;
  }

  .research-topic .area-carousel {
    height: 270px;
  }
}
/* Research video slides. */
.research-topic .carousel-slide video {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
  background: #02070c;
}

.research-video-slide {
  background: #02070c;
}
/* Keep the requested GNC sequence even before the carousel script finishes loading. */
#pontryagin-neural-networks { order: 1; }
#bellman-neural-networks { order: 2; }
#inspection-missions { order: 3; }
#lunar-landing { order: 4; }
#asteroid-proximity-operations { order: 5; }

.research-video-slide video {
  position: relative;
  z-index: 3;
  pointer-events: auto;
}