@font-face {
  font-family: "PT Sans";
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url("fonts/pt-sans-bold.woff2") format("woff2");
}

:root {
  --color-bg: #ffffff;
  --color-text: #24211d;
  --color-muted: #6b6459;
  --color-accent: #b1541f;
  --color-accent-dark: #8a3e15;
  --color-line: #e3dccf;
  --color-badge: #6e9cb3;
  --color-badge-dark: #4f7891;
  --font-serif: Georgia, "Times New Roman", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.5;
}

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

img {
  max-width: 100%;
  display: block;
  -webkit-user-drag: none;
  user-drag: none;
}

/* Header */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 2rem;
  border-bottom: 1px solid var(--color-line);
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--color-bg);
}

.logo {
  font-family: var(--font-sans);
  font-size: clamp(0.8rem, 3.2vw, 1.1rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #4a453d;
}

.site-byline {
  font-family: Arial, sans-serif;
  font-size: 1.4rem;
  color: var(--color-badge);
  width: 33.333%;
  text-align: center;
  margin: 1rem 0 0;
}

.main-nav ul {
  display: flex;
  gap: 1.75rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.main-nav a {
  font-size: 0.9rem;
  color: var(--color-text);
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.15s ease;
}

.main-nav a:hover,
.main-nav a:focus-visible {
  border-color: var(--color-accent);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.4rem;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  margin: 5px 0;
}

/* Hero */

.hero-stack {
  width: 33.333%;
  min-width: 320px;
  margin: 4rem auto 2.5rem;
}

.hero {
  position: relative;
  width: 100%;
  border-radius: 4px;
}

.hero-img {
  width: 100%;
  height: auto;
  border-radius: 4px;
  transform: scaleX(1.08) scaleY(0.92);
  transform-origin: center;
}

.hero-caption {
  text-align: center;
  margin-top: 0.6rem;
}

.hero-caption h1 {
  font-family: var(--font-sans);
  font-style: italic;
  font-size: clamp(0.6rem, 1.8vw, 0.85rem);
  line-height: 1.25;
  color: #c2185b;
  margin: 0;
  font-weight: 600;
}

/* Badges */

.badge-row {
  display: flex;
  justify-content: center;
  gap: 0.6rem;
  margin-top: 0.85rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  background: var(--color-badge);
  color: #fff;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
  transition: background 0.15s ease, transform 0.15s ease;
}

.badge:hover,
.badge:focus-visible {
  background: var(--color-badge-dark);
  transform: translateY(-1px);
}

.badge-outline {
  background: transparent;
  color: var(--color-badge);
  border: 1px solid var(--color-badge);
}

.badge-outline:hover,
.badge-outline:focus-visible {
  background: var(--color-badge);
  color: #fff;
}

.badge-arrow {
  font-size: 0.65rem;
}

/* CTA card (used on the Collaboration stub page) */

.cta-card {
  background: var(--color-bg);
  padding: 1.75rem 2rem;
  min-height: 130px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.35rem;
  transition: background 0.15s ease;
}

.cta-card:hover,
.cta-card:focus-visible {
  background: #f1ebe0;
}

.cta-eyebrow {
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
}

.cta-title {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.cta-arrow {
  color: var(--color-accent);
  transition: transform 0.15s ease;
}

.cta-card:hover .cta-arrow {
  transform: translateX(3px);
}

/* Copy protection: block text selection on Sujin's own graph captions/sources/notes
   (both Insights and Research pages), but keep the paper abstract selectable since
   it's meant to be quoted/cited. */
.story,
.paper {
  user-select: none;
}

.paper-abstract {
  user-select: text;
}

/* Insights page */

.page-title {
  max-width: 960px;
  margin: 3rem auto 2.5rem;
  padding: 0 1.5rem;
  font-family: "PT Sans", Arial, sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: #6d9eeb;
  border-bottom: 1px solid var(--color-line);
  padding-bottom: 1rem;
}

.story {
  max-width: 960px;
  margin: 0 auto 3.5rem;
  padding: 0 1.5rem;
}

.story-title {
  font-family: Arial, sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1.4;
  margin: 0 0 1.25rem;
}

.story--accordion > summary.story-title {
  cursor: pointer;
  list-style: none;
  position: relative;
  padding: 0.75rem 2.75rem 0.9rem 0;
  margin: 0;
  border-bottom: 2px solid var(--color-badge);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.07);
}

.story--accordion > summary.story-title::-webkit-details-marker {
  display: none;
}

.story--accordion > summary.story-title::after {
  content: "+";
  position: absolute;
  right: 0.25rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.9rem;
  height: 1.9rem;
  border-radius: 50%;
  background: var(--color-badge);
  color: #fff;
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.9rem;
  text-align: center;
}

.story--accordion[open] > summary.story-title::after {
  content: "\2212";
}

.story--accordion[open] > summary.story-title {
  margin-bottom: 1.25rem;
}

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

.story-grid--split {
  align-items: start;
}

.story-substack {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.story-single {
  max-width: 62%;
  margin: 0 auto 0 8%;
}

.story-single--wide {
  max-width: 80%;
  margin: 0 auto;
}

.story-grid--compact .story-cell img {
  max-width: 82%;
  margin-left: auto;
  margin-right: auto;
}

.story-cell img {
  width: 100%;
  border: 1px solid var(--color-line);
  border-radius: 4px;
  margin-bottom: 0.5rem;
}

.story-desc {
  font-size: 0.8rem;
  color: var(--color-text);
  margin: 0;
}

.story-source p {
  font-size: 0.72rem;
  color: var(--color-muted);
  margin: 0 0 0.5rem;
}

.story-source a {
  color: var(--color-badge);
}

.story-link--news {
  color: #c2185b;
  font-style: italic;
}

.story-note {
  font-size: 0.72rem;
  font-style: italic;
  color: var(--color-muted);
  margin: 0 0 0.5rem;
}

.story > .story-source {
  margin-top: 0.25rem;
}

.story > .story-note {
  margin-top: -0.25rem;
}

@media (max-width: 720px) {
  .story-grid {
    grid-template-columns: 1fr;
  }
}

/* Research page */

.paper {
  max-width: 960px;
  margin: 0 auto 3.5rem;
  padding: 0 1.5rem;
}

.paper-grid {
  display: grid;
  grid-template-columns: 43% 57%;
  gap: 2rem;
  align-items: start;
}

.paper-figure img {
  width: 100%;
  border: 1px solid var(--color-line);
  border-radius: 4px;
}

.paper-title {
  font-family: Arial, sans-serif;
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.45;
  margin: 0 0 0.9rem;
  color: var(--color-text);
}

.paper-title-highlight {
  color: var(--color-badge);
}

.paper-link-label {
  color: #d6598b;
}

.paper-abstract {
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--color-text);
  margin: 0 0 0.9rem;
}

.paper-note {
  font-size: 0.72rem;
  font-style: italic;
  color: var(--color-muted);
  margin: 0.6rem 0 0;
}

.paper-figure-caption {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--color-text);
  text-align: center;
  margin: 0.6rem 0 0;
}

.paper-substudy {
  font-size: 0.72rem;
  color: var(--color-text);
  margin: 0.6rem 0 0.4rem;
}

.paper-link {
  font-size: 0.72rem;
  margin: 0;
}

@media (max-width: 720px) {
  .paper-grid {
    grid-template-columns: 1fr;
  }
}

.paper--accordion > summary.paper-title {
  cursor: pointer;
  list-style: none;
  position: relative;
  padding: 0.75rem 2.75rem 0.9rem 0;
  margin: 0;
  border-bottom: 2px solid var(--color-badge);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.07);
}

.paper--accordion > summary.paper-title::-webkit-details-marker {
  display: none;
}

.paper--accordion > summary.paper-title::after {
  content: "+";
  position: absolute;
  right: 0.25rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.9rem;
  height: 1.9rem;
  border-radius: 50%;
  background: var(--color-badge);
  color: #fff;
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.9rem;
  text-align: center;
}

.paper--accordion[open] > summary.paper-title::after {
  content: "\2212";
}

.paper--accordion[open] > summary.paper-title {
  margin-bottom: 1rem;
}

.paper-empty {
  font-size: 0.82rem;
  color: var(--color-muted);
  font-style: italic;
  margin: 0;
}

/* Footer */

.site-footer {
  padding: 1.5rem 2rem;
  border-top: 1px solid var(--color-line);
  font-size: 0.75rem;
  color: var(--color-muted);
  text-align: center;
}

/* Responsive */

@media (max-width: 720px) {
  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-line);
    display: none;
  }

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

  .main-nav ul {
    flex-direction: column;
    gap: 0;
    padding: 0.5rem 2rem 1rem;
  }

  .main-nav li {
    padding: 0.6rem 0;
    border-bottom: 1px solid var(--color-line);
  }

  .nav-toggle {
    display: block;
  }
}