/* =========================================================
   HuMI project page
   ========================================================= */
:root {
  --bg:        #ffffff;
  --ink:       #1e1e1e;
  --ink-soft:  #555555;
  --ink-mute:  #8a8a8a;
  --line:      #e5e7ef;
  --primary:   #1f6fff;
  --primary-2: #1456c8;
  --sans:      "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --mono:      "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-2); }
img, video { max-width: 100%; display: block; }

/* =========================================================
   Sentinel + Floating Nav
   ========================================================= */
#nav-trigger {
  position: absolute;
  top: 80vh;
  left: 0;
  width: 1px;
  height: 1px;
  pointer-events: none;
}

.floating-nav {
  position: fixed;
  top: 50%;
  right: 18px;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: flex-end;
  opacity: 0;
  pointer-events: none;
  transition: opacity .35s ease;
}
.floating-nav.visible {
  opacity: 1;
  pointer-events: auto;
}
.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink-soft);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  padding: 4px 0;
}
.nav-item:hover { color: var(--ink); }
.nav-text {
  opacity: 0;
  transform: translateX(8px);
  transition: opacity .25s ease, transform .25s ease;
  background: rgba(255, 255, 255, .9);
  padding: 4px 10px;
  border-radius: 999px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, .08);
  pointer-events: none;
}
.nav-item:hover .nav-text,
.nav-item.active .nav-text {
  opacity: 1;
  transform: translateX(0);
}
.nav-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid var(--ink-soft);
  background: transparent;
  transition: all .2s ease;
}
.nav-item.active .nav-dot {
  background: var(--primary);
  border-color: var(--primary);
  transform: scale(1.2);
}

/* =========================================================
   Hero (full-screen video bg)
   ========================================================= */
.hero {
  position: relative;
  overflow: hidden;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}
.hero-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, .45);
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  width: 90vw;
  max-width: 1200px;
  text-align: center;
  padding: 4rem 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .35rem;
}
.hero-headline {
  margin: 0;
  color: #fff;
  font-weight: 700;
  font-size: clamp(5.5rem, 13vw, 11rem);
  line-height: 1;
  letter-spacing: -0.02em;
  text-shadow: 0 10px 30px rgba(0, 0, 0, .45);
}
.hero-subtitle {
  margin: 0;
  color: #fff;
  font-weight: 400;
  font-size: clamp(1.5rem, 2.8vw, 2.6rem);
  line-height: 1.25;
}
.hero-authors {
  width: min(95%, 900px);
  margin: 1.25rem 0 0;
  color: rgba(255, 255, 255, .9);
  font-size: clamp(1rem, 1.6vw, 1.35rem);
  line-height: 1.6;
}
.hero-author {
  display: inline-block;
  white-space: nowrap;
  color: inherit;
  text-decoration: none;
}
.hero-author-name {
  display: inline-block;
  padding: 0 .2em;
  border-radius: .25em;
  transition: background-color .15s ease;
}
a.hero-author:hover .hero-author-name {
  background-color: rgba(120, 190, 255, .3);
  text-decoration: underline;
}
.hero-author-star {
  color: rgba(255, 255, 255, .9);
}
.hero-footnote {
  margin: .25rem 0 0;
  color: rgba(255, 255, 255, .9);
  font-size: clamp(.85rem, 1.2vw, 1rem);
}
.hero-footnote-star { padding-right: .15em; }

.hero-buttons {
  margin-top: 2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  justify-content: center;
}
.hero-btn {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  background: rgba(255, 255, 255, .9);
  color: rgba(0, 0, 0, .7);
  border-radius: 999px;
  padding: .8rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 500;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(0, 0, 0, .15);
  transition: background-color .2s, color .2s, transform .12s;
}
.hero-btn:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-1px);
}
.hero-btn-icon {
  width: 1.15em;
  height: 1.15em;
  opacity: .7;
  transition: opacity .2s;
}
.hero-btn:hover .hero-btn-icon { opacity: 1; }
.hero-btn-disabled {
  background: rgba(255, 255, 255, .7) !important;
  color: rgba(0, 0, 0, .4) !important;
  cursor: not-allowed;
  pointer-events: auto;
}
.hero-btn-disabled:hover {
  background: rgba(255, 255, 255, .7) !important;
  color: rgba(0, 0, 0, .4) !important;
  transform: none;
}
.hero-btn-disabled .hero-btn-icon { opacity: .4; }

/* =========================================================
   Hero with no background video → solid backdrop
   ========================================================= */
.hero-video:not([src]) { display: none; }
.hero:has(.hero-video:not([src])) {
  background: linear-gradient(135deg, #1f1f1f 0%, #2b3a55 60%, #1f6fff 140%);
}

/* =========================================================
   Generic media placeholder
   ========================================================= */
.media-placeholder {
  position: relative;
  width: 100%;
  aspect-ratio: 16/9;
  background:
    repeating-linear-gradient(135deg,
      rgba(0,0,0,.04) 0 12px,
      rgba(0,0,0,.07) 12px 24px),
    #ececf2;
  border-radius: inherit;
  overflow: hidden;
}
.media-placeholder::after {
  content: "Add media";
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(0,0,0,.35);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: .04em;
  text-transform: uppercase;
  pointer-events: none;
}
.placeholder-square { aspect-ratio: 1 / 1; }
.placeholder-wide   { aspect-ratio: 21 / 9; }

/* =========================================================
   Panels (sections)
   ========================================================= */
.panel {
  width: 100%;
  padding: clamp(2rem, 5vw, 4rem) 0;
}
.panel-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}
.section-title {
  text-align: center;
  width: 100%;
  margin: 0 0 2rem;
  font-size: clamp(1.35rem, 1.8vw, 1.75rem);
  font-weight: 700;
  color: var(--ink);
  letter-spacing: -.005em;
}

/* =========================================================
   Capabilities — 2x2 grid
   ========================================================= */
.cap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}
.cap-card {
  background: #fff;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 3px 16px rgba(0, 0, 0, .12);
  display: flex;
  flex-direction: column;
}
.cap-video {
  background: #000;
  aspect-ratio: 9/10; /* portrait — matches the source clips so cropping is minimal */
}
.cap-video video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.cap-foot {
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  text-align: center;
}
.cap-title {
  font-size: 1rem;
  font-weight: 500;
}
.cap-next {
  background: transparent;
  border: 0;
  color: var(--primary);
  font: 500 14px var(--sans);
  cursor: pointer;
  padding: 6px 10px;
  border-radius: 6px;
  transition: background-color .15s;
}
.cap-next:hover { background: rgba(31, 111, 255, .08); }

/* 5th card: span both columns but keep one-column width, centered */
.cap-card-center {
  grid-column: 1 / -1;
  justify-self: center;
  width: calc(50% - 1rem); /* matches a single-column card (gap is 2rem) */
}

/* =========================================================
   Generalization — task tabs + object selector + comparison
   ========================================================= */
.task-intro {
  max-width: 80ch;
  margin: 0 auto 2rem;
  text-align: center;
  color: var(--ink-soft);
  font-size: 1rem;
  line-height: 1.65;
}

.task-tabs {
  display: flex;
  justify-content: center;
  gap: .25rem;
  margin: 0 auto 1.25rem;
  border-bottom: 1px solid var(--line);
}
.task-tab {
  background: transparent;
  border: 0;
  border-bottom: 3px solid transparent;
  padding: .7rem 1.5rem;
  margin-bottom: -1px;
  font: 600 1rem var(--sans);
  color: var(--ink-soft);
  cursor: pointer;
  transition: color .2s, border-color .2s;
}
.task-tab:hover { color: var(--ink); }
.task-tab.is-active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.object-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .55rem;
  margin: 1.25rem auto .75rem;
}
.obj-btn {
  border: 2px solid var(--ink-mute);
  background: transparent;
  color: var(--ink-soft);
  border-radius: 999px;
  padding: .4rem 1rem;
  font: 500 .9rem var(--sans);
  cursor: pointer;
  transition: background-color .15s, color .15s, transform .12s;
}
.obj-btn:hover { transform: translateY(-1px); }
.obj-btn[data-cat="seen"]   { border-color: #2e9d51; color: #2e9d51; }
.obj-btn[data-cat="human"]  { border-color: #d4a017; color: #d4a017; }
.obj-btn[data-cat="unseen"] { border-color: #d83a4d; color: #d83a4d; }
.obj-btn.is-active[data-cat="seen"]   { background: #2e9d51; color: #fff; }
.obj-btn.is-active[data-cat="human"]  { background: #d4a017; color: #fff; }
.obj-btn.is-active[data-cat="unseen"] { background: #d83a4d; color: #fff; }
.obj-btn[hidden] { display: none; }

.task-legend {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
  margin: .25rem 0 1rem;
  font-size: .9rem;
  color: var(--ink-soft);
}
.legend-item {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
}
.legend-dot {
  width: 12px;
  height: 12px;
  border-radius: 3px;
}
.legend-seen   { background: #2e9d51; }
.legend-human  { background: #d4a017; }
.legend-unseen { background: #d83a4d; }

.speed-indicator {
  text-align: center;
  margin: .25rem 0 1.5rem;
  font-weight: 600;
  font-size: 1rem;
  color: var(--ink-soft);
}

.task-compare {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}
.task-col {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.task-col-title {
  margin: 0 0 .65rem;
  font-size: .95rem;
  font-weight: 600;
  color: var(--ink-soft);
  text-align: center;
}
.task-col-title-primary { color: var(--primary); }

.task-video {
  position: relative;
  width: 100%;
  aspect-ratio: 16/9;
  border-radius: 10px;
  overflow: hidden;
  background: #000;
  border: 2px solid var(--line);
}
.task-col-primary .task-video { border-color: var(--primary); }
.task-video video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.task-video video:not([src]):not(:has(source[src])) { display: none; }
.task-video > .media-placeholder {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  aspect-ratio: auto;
  border-radius: 0;
}

/* =========================================================
   Data collection: bag animation + compare
   ========================================================= */
.backpack {
  position: relative;
  width: 100%;
  max-width: 900px;
  margin: 0 auto 2rem;
  aspect-ratio: 16/9;
  display: flex;
  align-items: center;
  justify-content: center;
}
.backpack-text {
  position: absolute;
  z-index: 2;
  left: 6%;
  top: 50%;
  transform: translateY(-50%);
  max-width: 260px;
  text-align: center;
  cursor: pointer;
  transition: opacity .6s ease, transform .6s ease;
}
.backpack[data-step="2"] .backpack-text {
  opacity: 0;
  transform: translate(-40px, -50%);
  pointer-events: none;
}
.backpack-text h3 {
  margin: 0 0 .8rem;
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.2;
}
.backpack-cta {
  margin: 0;
  color: var(--primary);
  font-weight: 700;
  font-size: 1rem;
}

.backpack-images {
  position: relative;
  width: 60%;
  height: 100%;
  margin-left: auto;
  cursor: pointer;
}
.backpack-images img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: opacity .4s ease, transform .6s cubic-bezier(.34,1.56,.64,1);
}
.bag-closed { opacity: 1; }
.bag-open   { opacity: 0; transform: scale(.85); }

.backpack[data-step="1"] .bag-closed { opacity: 0; }
.backpack[data-step="1"] .bag-open   { opacity: 1; transform: scale(1); }
.backpack[data-step="2"] .bag-closed { opacity: 0; }
.backpack[data-step="2"] .bag-open   { opacity: 0; transform: translateX(80px); }

.backpack-video {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(.95);
  pointer-events: none;
  transition: opacity 1s ease, transform 1s ease;
  z-index: 1;
}
.backpack-video video {
  width: 100%;
  max-width: 700px;
  border-radius: 10px;
  background: #000;
  box-shadow: 0 4px 18px rgba(0, 0, 0, .15);
}
.backpack[data-step="2"] .backpack-video {
  opacity: 1;
  transform: scale(1);
  pointer-events: auto;
  z-index: 3;
}

.dc-compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-top: 1.5rem;
}
.dc-card {
  background: #fff;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 3px 16px rgba(0, 0, 0, .12);
}
.dc-video {
  position: relative;
  background: #000;
  aspect-ratio: 16/9;
}
.dc-video video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.dc-label {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 2;
  padding: 4px 12px;
  border-radius: 4px;
  color: #fff;
  font-size: .85rem;
  font-weight: 700;
}
.dc-label-primary { background: var(--primary); }
.dc-label-dark    { background: #333; }

.dc-stats {
  padding: 1.5rem;
  text-align: center;
}
.dc-num {
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--primary);
  line-height: 1;
}
.dc-num-muted { color: var(--ink-mute); }
.dc-stat-label {
  margin-top: .3rem;
  font-weight: 500;
}
.dc-stat-sub {
  color: var(--ink-mute);
  font-size: .85rem;
  margin-top: .1rem;
}

/* =========================================================
   Abstract
   ========================================================= */
.panel-text {
  padding: clamp(2rem, 5vw, 4rem) 1.5rem;
}
.abstract-inner {
  max-width: 80ch;
  margin: 0 auto;
}
.abstract-text {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--ink);
  text-align: justify;
}

/* =========================================================
   Figure wrapper + caption (Framework, Hardware, Results)
   ========================================================= */
.figure-wrap {
  display: flex;
  justify-content: center;
  margin: 0 auto;
}
.figure-wrap img,
.figure-wrap .media-placeholder {
  width: 100%;
  max-width: min(90%, 1000px);
  border-radius: 10px;
  display: block;
}
.figure-caption {
  margin: 1rem auto 0;
  max-width: 80ch;
  text-align: center;
  font-size: .95rem;
  color: var(--ink-soft);
  line-height: 1.55;
}

/* =========================================================
   Results table (academic / booktabs-style)
   ========================================================= */
.results-table-wrap {
  width: 100%;
  overflow-x: auto;
  margin: 0 auto;
  max-width: 1000px;
}
.results-table {
  width: 100%;
  border-collapse: collapse;
  font-size: .95rem;
  border-top:    2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
}
.results-table thead th {
  font-weight: 600;
  text-align: center;
  padding: 10px 14px;
  border-bottom: 1px solid var(--ink);
  white-space: nowrap;
}
.results-table th.th-left,
.results-table td.td-left {
  text-align: left;
  padding-left: 4px;
}
.results-table td {
  text-align: center;
  padding: 9px 14px;
  font-variant-numeric: tabular-nums;
}
.results-table tbody tr.row-divider td {
  border-bottom: 1px solid rgba(0,0,0,.25);
}
.results-table tbody tr:hover td {
  background: rgba(31, 111, 255, .04);
}
.results-table .arrow {
  color: var(--ink-mute);
  font-weight: 500;
  margin-left: 2px;
}

/* =========================================================
   Teaser image
   ========================================================= */
.panel-teaser-image {
  padding-top: 0;
}
.teaser-image-wrap {
  display: flex;
  justify-content: center;
  padding: 0 24px;
}
.teaser-image-wrap img {
  width: min(65vw, 82ch);
  border-radius: 10px;
}

/* =========================================================
   BibTeX
   ========================================================= */
.panel-cite { padding-bottom: 4rem; }
.cite-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .8rem;
  padding: 0 24px;
}
.cite-wrap {
  position: relative;
  width: min(65vw, 82ch);
}
.cite-copy {
  position: absolute;
  top: .6rem;
  right: .7rem;
  z-index: 1;
  border: 1px solid rgba(127, 127, 127, .36);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, .85);
  color: var(--ink);
  padding: 0;
  cursor: pointer;
  opacity: 0;
  transform: translateY(-2px);
  transition: opacity .2s ease, transform .2s ease, background-color .2s ease;
}
.cite-copy svg { width: 16px; height: 16px; }
.cite-wrap:hover .cite-copy,
.cite-wrap:focus-within .cite-copy { opacity: 1; transform: translateY(0); }
.cite-copy:hover { background: #fff; }
.cite-copy.copied {
  opacity: 1;
  background: #e7f7ec;
  border-color: #2e9d51;
  color: #2e9d51;
}

.cite-code {
  margin: 0;
  padding: 1rem 4.8rem 1rem 1.1rem;
  border-radius: 10px;
  border: 1px solid rgba(127, 127, 127, .28);
  background: rgba(127, 127, 127, .08);
  color: var(--ink);
  font-family: var(--mono);
  font-size: clamp(.82rem, 1vw, .95rem);
  line-height: 1.55;
  overflow-x: auto;
  white-space: pre;
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 900px) {
  .cap-grid { grid-template-columns: 1fr; }
  .cap-card-center { width: 100%; }
  .dc-compare { grid-template-columns: 1fr; }
  .task-compare { grid-template-columns: 1fr; }
  .task-tab { padding: .6rem 1rem; font-size: .9rem; }
  .floating-nav { right: 10px; gap: 10px; }
  .nav-text { font-size: 12px; }

  .backpack {
    aspect-ratio: auto;
    flex-direction: column;
    gap: 1rem;
    height: auto;
  }
  .backpack-text {
    position: static;
    transform: none;
    max-width: 100%;
  }
  .backpack-images {
    width: 80%;
    height: 280px;
    margin: 0 auto;
  }
  .backpack[data-step="2"] .backpack-text {
    transform: translateY(-40px);
  }
}

@media (max-width: 600px) {
  .hero-buttons { gap: .75rem; }
  .hero-btn { padding: .65rem 1.1rem; font-size: .95rem; }
  .teaser-image-wrap img,
  .teaser-image-wrap .media-placeholder,
  .cite-wrap { width: 95vw; }
  .cite-code { padding-right: 4.4rem; }
}

/* =========================================================
   Placeholder overrides — must beat .cap-video / .env-video /
   .dc-video / .backpack-* backgrounds and aspect rules.
   ========================================================= */
.cap-video.media-placeholder,
.task-video > .media-placeholder,
.dc-video > .media-placeholder,
.backpack-video .media-placeholder {
  background:
    repeating-linear-gradient(135deg,
      rgba(0,0,0,.04) 0 12px,
      rgba(0,0,0,.07) 12px 24px),
    #ececf2;
}
.backpack-images .media-placeholder {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  aspect-ratio: auto;
  border-radius: 8px;
  background:
    repeating-linear-gradient(135deg,
      rgba(0,0,0,.04) 0 12px,
      rgba(0,0,0,.07) 12px 24px),
    #ececf2;
}
.teaser-image-wrap .media-placeholder {
  width: min(65vw, 82ch);
  border-radius: 10px;
}