@import url("https://fonts.googleapis.com/css2?family=Playfair+Display:wght@500&family=Inter:wght@300;400;500&display=swap");

.page-header {
  text-align: center;
  padding: 3.5rem 1rem 2rem;
  position: relative; /* <-- important for absolute positioning */
}

.back-desktop {
  position: absolute;
  top: rem; /* ⬇ move this value to push button down */
  left: 1rem;

  padding: 0.3rem 0.9rem;
  border-radius: 999px;
  border: 1px solid #6078cf;
  background: #f3f4f0;
  color: #2e4185;
  font-size: 0.85rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

/* optional hover state */
.back-desktop:hover {
  background: #e4e6df;
}

body {
  margin: 0;
  background: #eff1e8;
  color: #2e4185;
  font-family: "Inter", sans-serif;
}

/* ===== Header ===== */
.page-header {
  text-align: center;
  padding: 1rem 1rem 2rem;
  border-bottom: 3px dotted #eee;
}

.page-header h1 {
  font-family: "Playfair Display", serif;
  font-size: 2.3rem;
  margin-top: 4.5rem;
  margin-bottom: 0.4rem;
  font-weight: 500;
}

.subtitle {
  color: #2e4185;
  font-size: 1rem;
}

.concept-text {
  font-size: 0.9rem;
  color: #6078cf;
  font-style: italic;
  max-width: 600px;
  margin: 0.8rem auto 0;
  line-height: 1.3;
}

/* ===== Top-level mode buttons ===== */

.archive-switch {
  display: flex;
  justify-content: center;
  gap: 3rem;
  margin: 1.5rem 0 0.3rem;
}

.titlebutton {
  position: relative; /* ← add this line */
  font-size: 0.95rem;
  color: #2e4185;
  border-radius: 999px;
  border: 0.5px solid #6078cf;
  background: #d0d2cb;
  padding: 0.4rem 1.8rem;
  line-height: 1.8;
  cursor: pointer;
  transition: background 0.2s ease, box-shadow 0.2s ease, color 0.2s ease;
}

/* Hover tooltip for buttons that have data-tooltip */
.titlebutton[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  left: 100%;
  top: 115%;
  transform: translateX(-50%);
  white-space: nowrap;
  background: #9eade5;
  color: #ffffff;
  font-size: 0.75rem;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.18);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
  z-index: 10;
}

.titlebutton[data-tooltip]:hover::after {
  opacity: 1;
}

.titlebutton--active {
  background: #f3f4f0;
  box-shadow: 0 0 0 1px #6078cf;
}

/* ===== Sections (docs vs dataviz) ===== */

.archive-section {
  display: none;
}

.archive-section.active {
  display: block;
}

/* Arrow that visually links the active titlebutton to its subtabs */
.section-arrow {
  width: 0;
  height: 0;
  border-left: 9px solid transparent;
  border-right: 9px solid transparent;
  border-top: 9px solid #5c80ff;
  margin: 1rem auto 1.5rem;
}

/* ===== Subtabs ===== */

.subtabs {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 0 0 2.5rem;
}

.tab {
  border: 1px solid #6078cf;
  border-radius: 999px;
  background: #ffffff;
  color: #2e4185;
  font-size: 0.9rem;
  padding: 0.35rem 1.1rem;
  cursor: pointer;
  transition: all 0.25s ease;
}

.tab:hover {
  border-color: #2e4185;
  color: #003cff;
}

.tab.active {
  background: #576dbd;
  color: #ffffff;
  border-color: #2e4185;
}

/* ===== Docs Grid ===== */
.grid {
  column-count: 4;
  column-gap: 1.8rem;
  max-width: 2000px;
  margin: 0 auto;
  padding: 0 2rem 5rem;
}
/* Stamp-style card */
.card {
  position: relative;
  z-index: 0;
  padding: 1rem;
  border: 3px dotted #808bb0; /* perforated edge */
  border-radius: 18px;
  background: transparent;
  box-shadow: 0 3px 8px rgba(0, 0, 0, 0.2);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  overflow: hidden;
  break-inside: avoid;
  margin-bottom: 1.8rem;
  display: block;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}
.card-link {
  display: block;
  color: inherit;
  text-decoration: line-through;
}

.card-link:hover {
  text-decoration: dashed;
}

@media (max-width: 1500px) {
  .grid {
    column-count: 3;
  }
}

@media (max-width: 1000px) {
  .grid {
    column-count: 2;
  }
}

@media (max-width: 600px) {
  .grid {
    column-count: 1;
  }
}

.thumb {
  width: 100%;
  background-size: cover;
  background-position: center;
  background-color: #98a3b7;
  min-height: 160px;
  max-height: 280px;
}

.info {
  padding: 1rem;
}

.info h2 {
  font-family: "Playfair Display", serif;
  font-size: 1.1rem;
  margin: 0 0 0.3rem;
}

.info .meta {
  color: #5d6a96;
  font-size: 0.85rem;
  font-style: italic;
}

/* ===== Data Visualization panel ===== */

.dataviz-panel {
  max-width: 700px;
  margin: 0 auto 4rem;
  padding: 1.5rem 2rem 2rem;
  border-radius: 12px;
  border: 2px dashed #6078cf;
  background: rgba(255, 255, 255, 0.7);
}

#datavizCanvas {
  width: 100%;
  max-height: 360px;
}

.dataviz-note {
  margin-top: 0.8rem;
  font-size: 0.85rem;
  color: #4a5694;
  font-style: italic;
  text-align: center;
}

/* 3D thumbnail styling */
.card model-viewer {
  object-fit: contain;
  border-radius: 12px;
}