/* ============================================================
   SPENCER LAB — DESIGN TOKENS
   Fonts: Source Serif 4 (display/headlines) + Source Sans 3 (body/UI)
   — the same type family Stanford's own identity system uses —
   paired with the official Stanford color palette.
   ============================================================ */

:root {
  /* Stanford primary palette */
  --cardinal:      #8C1515;
  --cardinal-dark:  #820000;
  --black:          #2E2D29;
  --cool-gray:      #4D4F53;
  --gray-40:        #ABABA9;
  --gray-20:        #D5D5D4;
  --gray-10:        #EAEAEA;
  --white:          #FFFFFF;

  /* Accent (chosen to pair with Cardinal Red) */
  --palo-alto:       #175E54;
  --palo-alto-light: #2D716F;

  /* Surface tints */
  --bg:            var(--white);
  --bg-alt:        #F7F6F3;   /* warm-neutral section break, not pure gray */

  /* Type */
  --font-display: "Source Serif 4", "Source Serif Pro", Georgia, serif;
  --font-body:    "Source Sans 3", "Source Sans Pro", -apple-system, sans-serif;

  /* Rhythm */
  --max-width: 960px;
  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.75rem;
  --space-4: 3rem;
  --space-5: 5rem;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--black);
  background: var(--bg);
  line-height: 1.6;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--palo-alto);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease;
}
a:hover, a:focus { border-bottom-color: var(--palo-alto); }
a:focus-visible {
  outline: 2px solid var(--palo-alto);
  outline-offset: 2px;
}

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  margin: 0 0 var(--space-2);
  color: var(--black);
}
h1 { font-size: clamp(2.1rem, 5vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 3vw, 1.9rem); }
h3 { font-size: 1.15rem; }

p { margin: 0 0 var(--space-2); }

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-3);
}
/* ---------- Home Photo ---------- */

.home-photo {
  padding: var(--space-3) 0 0;
}
.home-photo img {
  width: 100%;
  max-height: 420px;
  object-fit: cover;
  border-radius: 4px;
  display: block;
}

/* ---------- carousel ---------- */

.carousel-viewport {
  position: relative;
  overflow: hidden;
  border-radius: 4px;
  margin: var(--space-4) 0;
}
.carousel-track {
  display: flex;
  transition: transform 0.5s ease;
}
.carousel-slide {
  flex: 0 0 100%;
  aspect-ratio: 16 / 7;
}
.carousel-slide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.carousel-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255,255,255,0.85);
  border: none;
  color: var(--black);
  font-size: 1.8rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  cursor: pointer;
  line-height: 1;
}
.carousel-arrow:hover { background: var(--white); color: var(--cardinal); }
.carousel-arrow.prev { left: var(--space-2); }
.carousel-arrow.next { right: var(--space-2); }

/* ---------- header / nav ---------- */
.site-header {
  border-bottom: 3px solid var(--cardinal);
  padding: var(--space-3) 0 var(--space-2);
}
.site-header .wrap {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
}
.site-title {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--black);
  text-decoration: none;
  border-bottom: none;
}
.site-title:hover { border-bottom: none; color: var(--cardinal); }
.site-title .dept {
  display: block;
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cool-gray);
  margin-top: 2px;
}

nav.main-nav ul {
  list-style: none;
  display: flex;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
}
nav.main-nav a {
  color: var(--black);
  font-size: 0.95rem;
  font-weight: 600;
  border-bottom: 2px solid transparent;
  padding-bottom: 4px;
}
nav.main-nav a:hover,
nav.main-nav a.active {
  color: var(--cardinal);
  border-bottom-color: var(--cardinal);
}

/* ---------- hero ---------- */
.hero {
  padding: var(--space-5) 0 var(--space-4);
}
.hero .eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--palo-alto);
  margin-bottom: var(--space-2);
}
.hero h1 { max-width: 760px; }
.hero .lede {
  max-width: 640px;
  font-size: 1.15rem;
  color: var(--cool-gray);
}
.hero-rule {
  width: 64px;
  height: 4px;
  background: var(--palo-alto);
  margin: var(--space-3) 0;
  border: none;
}
.home-hero {
  padding: var(--space-5) 0 var(--space-5);
  background: var(--bg-alt);
}
.home-hero h1 {
  color: var(--cardinal);
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
}
.home-hero .lede {
  font-size: 1.25rem;
  color: var(--black);
}
.home-hero .eyebrow {
  font-size: 0.85rem;
}

/* ---------- generic sections ---------- */
.section {
  padding: var(--space-4) 0;
}
.section.alt {
  background: var(--bg-alt);
}
.section-label {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cool-gray);
  margin-bottom: var(--space-1);
}

/* ---------- cards / grids ---------- */
.grid {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin-top: var(--space-3);
}
.card {
  border-top: 3px solid var(--cardinal);
  padding-top: var(--space-2);
}
.card h3 { margin-bottom: var(--space-1); }
.card p { color: var(--cool-gray); font-size: 0.98rem; }

.home-card {
  border: 1px solid var(--cardinal);
  border-radius: 4px;
  padding: var(--space-3);
}
.home-card h3 {
  font-size: 1.4rem;
}

/* ---------- people ---------- */
.people-grid {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  margin-top: var(--space-3);
}
.person-photo {
  width: 100%;
  aspect-ratio: 1 / 1;
  background: var(--gray-10);
  border-radius: 4px;
  margin-bottom: var(--space-1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-40);
  font-size: 0.8rem;
  overflow: hidden;
}
.principal-investigator-grid .person-photo {
  max-width: 450px;
}
.principal-investigator-grid {
  grid-template-columns: 1fr;
}
.person-photo img { width: 100%; height: 100%; object-fit: cover; }
.person-name { font-weight: 700; margin-bottom: 0; }
.person-role {
  font-size: 0.85rem;
  color: var(--palo-alto-light);
  font-weight: 600;
  margin-bottom: var(--space-1);
}
.person-bio { font-size: 0.92rem; color: var(--cool-gray); }
.principal-investigator-grid {
  grid-template-columns: 1fr;
  justify-content: center;
  text-align: center;
}
.principal-investigator-grid .person-photo {
  max-width: 320px;
  margin-left: auto;
  margin-right: auto;
}

.bio-details {
  margin-top: 0.4rem;
}
.bio-details summary {
  cursor: pointer;
  color: var(--palo-alto);
  font-size: 0.88rem;
  font-weight: 600;
  list-style: none; /* removes default triangle in some browsers */
}
.bio-details summary:hover {
  border-bottom: 1px solid var(--palo-alto);
}
.bio-details summary::-webkit-details-marker {
  display: none; /* removes default triangle in Chrome/Safari */
}
.person-full-bio {
  margin-top: 0.5rem;
  font-size: 0.92rem;
  color: var(--cool-gray);
}
 .people-section {
  margin-bottom: var(--space-5);
}
.people-section:last-child {
  margin-bottom: 0;
}
.people-section-title {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cardinal);
  margin-bottom: var(--space-1);
}
.section-divider {
  border: none;
  border-top: 2px solid var(--gray-20);
  margin: 0 0 var(--space-3);
}
/* ---------- news ---------- */
.news-item {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: var(--space-3);
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--gray-20);
  align-items: start;
}
.news-item:first-child { border-top: 1px solid var(--gray-20); }
.news-image {
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: 4px;
}
.news-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.news-date {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--cool-gray);
  letter-spacing: 0.03em;
  margin-bottom: 4px;
}

@media (max-width: 640px) {
  .news-item { grid-template-columns: 1fr; }
}

/* ---------- labnews ---------- */
.feed-list {
  margin-top: var(--space-3);
  max-width: 640px;
}
.feed-item {
  padding: var(--space-2) 0;
  border-left: 2px solid var(--gray-20);
  padding-left: var(--space-3);
  margin-bottom: var(--space-2);
}
.feed-item h3 {
  font-size: 1rem;
  margin-bottom: 2px;
}
.feed-date {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--palo-alto);
  letter-spacing: 0.03em;
  margin-bottom: 2px;
}
.feed-item p {
  color: var(--cool-gray);
  font-size: 0.92rem;
  margin-bottom: 0;
}

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--gray-20);
  padding: var(--space-4) 0;
  margin-top: var(--space-4);
  color: var(--cool-gray);
  font-size: 0.88rem;
}
.site-footer a { color: var(--cool-gray); }
.site-footer a:hover { color: var(--cardinal); border-bottom-color: var(--cardinal); }

/*-----------publications----------*/
.pub-list {
  margin-top: var(--space-3);
}
.pub-list.featured .pub-item {
  border-left: 3px solid var(--cardinal);
  padding-left: var(--space-2);
}
.pub-item {
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--gray-20);
}
.pub-item:last-child {
  border-bottom: none;
}
.pub-item h3 {
  font-size: 1.05rem;
  margin-bottom: 4px;
}
.pub-authors {
  font-size: 0.92rem;
  color: var(--cool-gray);
  margin-bottom: 2px;
}
.pub-journal {
  font-size: 0.85rem;
  font-style: italic;
  color: var(--gray-40);
  margin-bottom: 0;
}

/* ---------- placeholder notice (remove once real content is in) ---------- */
.placeholder-note {
  background: #FFF7F0;
  border: 1px dashed var(--gray-40);
  color: var(--cool-gray);
  font-size: 0.85rem;
  padding: var(--space-2);
  border-radius: 4px;
  margin-bottom: var(--space-3);
}
.research-index {
  border-top: 1px solid var(--gray-20);
  border-bottom: 1px solid var(--gray-20);
  background: var(--bg-alt);
  position: sticky;
  top: 0;
  z-index: 10;
}
.research-index ul {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  list-style: none;
  margin: 0;
  padding: var(--space-2) 0;
}
.research-index a {
  font-weight: 700;
  font-size: 0.92rem;
  color: var(--cool-gray);
  border-bottom: 2px solid transparent;
  padding-bottom: 2px;
}
.research-index a:hover {
  color: var(--cardinal);
  border-bottom-color: var(--cardinal);
}

.research-block {
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--gray-20);
  scroll-margin-top: 80px;
}
.research-block:last-child {
  border-bottom: none;
}
.research-block h2 {
  color: var(--cardinal);
}

/* Sticky bar layout: nav links left, button pinned right */
.research-index-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
}
.clinical-studies-btn {
  flex-shrink: 0;
  background: var(--cardinal);
  color: var(--white);
  font-size: 0.85rem;
  font-weight: 700;
  padding: 8px 16px;
  border-radius: 4px;
  border-bottom: none;
}
.clinical-studies-btn:hover {
  background: var(--cardinal-dark);
  border-bottom: none;
}

/* Clinical trials section */
.trials-list {
  margin-top: var(--space-3);
  display: grid;
  gap: var(--space-4);
}
.trial-item {
  background: var(--white);
  border-left: 3px solid var(--palo-alto);
  padding: var(--space-3);
  border-radius: 4px;
}
.trial-item h3 {
  margin-bottom: var(--space-1);
}
.trial-criteria {
  font-size: 0.9rem;
  color: var(--cool-gray);
  margin-bottom: 4px;
}
.trial-link {
  display: inline-block;
  margin-top: var(--space-1);
  font-weight: 700;
}