/* ═══════════════════════════ TOKENS ═══════════════════════════ */
:root {
  --bg:         #f5f6fa;
  --bg-alt:     #eef0f6;
  --surface:    #ffffff;
  --surface-hi: #f8f9fc;
  --border:     #e2e5ee;
  --border-hi:  #d0d5e0;

  --ink:        #1a1e2e;
  --ink-2:      #3d4255;
  --ink-3:      #6b7189;
  --ink-4:      #9da2b6;

  --blue:       #3b6cef;
  --blue-soft:  rgba(59,108,239,0.09);
  --blue-med:   rgba(59,108,239,0.18);
  --green:      #16a163;
  --green-soft: rgba(22,161,99,0.09);
  --green-med:  rgba(22,161,99,0.18);
  --amber:      #d08819;
  --amber-soft: rgba(208,136,25,0.09);
  --amber-med:  rgba(208,136,25,0.18);
  --red:        #dc4848;
  --red-soft:   rgba(220,72,72,0.09);

  --r-xl: 20px;
  --r-lg: 14px;
  --r-md: 10px;
  --r-sm: 6px;

  --serif: 'Source Serif 4', Georgia, serif;
  --sans:  'DM Sans', system-ui, sans-serif;
  --mono:  'JetBrains Mono', 'Menlo', monospace;

  --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 40px rgba(0,0,0,0.08);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { overflow-x: clip; scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  overflow-x: clip;
  min-height: 100vh;
}

a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }

button, input, select { font: inherit; }

::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-hi); border-radius: 4px; }

/* ═══════════════════════════ TOPBAR ═══════════════════════════ */
.topbar {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; gap: 0;
  height: 56px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-xs);
  padding: 0 24px;
}

.logo {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--ink);
  margin-right: 32px; flex-shrink: 0;
}
.logo-mark {
  width: 32px; height: 32px;
  border-radius: 7px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.logo-mark img {
  width: 100%; height: 100%;
  object-fit: contain;
  display: block;
}
.logo-mark svg { width: 16px; height: 16px; }
.logo-text {
  font-family: var(--serif); font-size: 1.1rem; font-weight: 700;
  letter-spacing: -0.02em;
}

.topbar-spacer { flex: 1; }
.topbar-right {
  display: flex; align-items: center; gap: 10px;
  margin-left: auto; flex-shrink: 0;
}
.badge-venue {
  display: flex; align-items: center; gap: 6px;
  padding: 4px 12px; border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-soft), var(--green-soft));
  border: 1px solid var(--blue-med);
  font-size: 0.74rem; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--blue);
}
.topbar-link {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-radius: var(--r-sm);
  font-size: 0.84rem; font-weight: 500;
  color: var(--ink-3); text-decoration: none;
  transition: background 0.15s, color 0.15s;
}
.topbar-link:hover { background: var(--bg-alt); color: var(--ink); text-decoration: none; }
.topbar-link svg { width: 15px; height: 15px; stroke: currentColor; fill: none; stroke-width: 1.8; }

/* ═══════════════════════════ PAGE SHELL ═══════════════════════════ */
.page {
  max-width: 1460px; margin: 0 auto;
  padding: 28px 24px 60px;
}

/* Subtle fade-in on load */
.paper-wrap > * {
  animation: fade-up 0.45s cubic-bezier(0.22,1,0.36,1) both;
}
.paper-wrap > *:nth-child(1) { animation-delay: 0.03s; }
.paper-wrap > *:nth-child(2) { animation-delay: 0.09s; }
.paper-wrap > *:nth-child(3) { animation-delay: 0.15s; }
.paper-wrap > *:nth-child(4) { animation-delay: 0.21s; }
.paper-wrap > *:nth-child(5) { animation-delay: 0.27s; }
.paper-wrap > *:nth-child(n+6) { animation-delay: 0.33s; }

@keyframes fade-up {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ═══════════════════════════ PAPER / PROJECT PAGE ═══════════════════════════ */
.paper-wrap {
  max-width: 860px; margin: 0 auto;
}

.paper-hero {
  text-align: center;
  padding: 40px 0 32px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 32px;
}

.paper-venue-badge {
  display: inline-block;
  padding: 3px 12px; border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-soft), var(--green-soft));
  border: 1px solid var(--blue-med);
  font-size: 0.72rem; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--blue);
  margin-bottom: 20px;
}

.paper-title {
  font-family: var(--serif);
  font-size: clamp(1.5rem, 3.2vw, 2.2rem);
  font-weight: 700; line-height: 1.22;
  letter-spacing: -0.025em;
  color: var(--ink);
  max-width: 760px; margin: 0 auto 28px;
}
.paper-title-icon {
  display: inline-block;
  width: 1.6em; height: 1.6em;
  vertical-align: -0.36em;
  margin-right: 0.32em;
  object-fit: contain;
  filter: drop-shadow(0 2px 6px rgba(59,108,239,0.18));
}
@media (max-width: 480px) {
  .paper-title-icon { width: 1.4em; height: 1.4em; vertical-align: -0.32em; }
}
.paper-title .method-name {
  font-variant: small-caps;
  letter-spacing: 0.01em;
  background: linear-gradient(135deg, var(--blue), var(--green));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.paper-author-list {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 4px 20px;
  font-size: 0.97rem; font-weight: 500; color: var(--ink-2);
  margin-bottom: 10px;
}
.paper-author-list a { color: var(--ink-2); font-weight: 500; }
.paper-author-list a:hover { color: var(--blue); text-decoration: none; }
.paper-author-list sup { font-size: 0.65rem; color: var(--ink-4); }

.paper-affil {
  font-size: 0.84rem; color: var(--ink-3); margin-bottom: 6px;
  display: flex; flex-wrap: wrap; justify-content: center; gap: 4px 18px;
}
.paper-affil-item { display: flex; align-items: center; gap: 5px; }
.paper-affil-icon { width: 16px; height: 16px; opacity: 0.6; }

.paper-eq-note {
  font-size: 0.78rem; color: var(--ink-4);
  margin-bottom: 28px;
}
.paper-eq-note sup { font-size: 0.65rem; }

.paper-btns {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 10px;
  margin-top: 8px;
}
.paper-btn {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 8px 18px; border-radius: var(--r-md);
  font-size: 0.86rem; font-weight: 600;
  border: 1.5px solid var(--border);
  background: var(--surface); color: var(--ink-2);
  cursor: pointer; text-decoration: none;
  transition: background 0.2s, border-color 0.2s, color 0.2s, transform 0.2s, box-shadow 0.2s;
  box-shadow: var(--shadow-xs);
}
.paper-btn:hover { background: var(--bg-alt); border-color: var(--border-hi); color: var(--ink); transform: translateY(-1px); box-shadow: var(--shadow-sm); text-decoration: none; }
.paper-btn svg { width: 16px; height: 16px; stroke: currentColor; fill: none; stroke-width: 1.8; flex-shrink: 0; }
.paper-btn.btn-primary { background: var(--blue); border-color: var(--blue); color: #fff; }
.paper-btn.btn-primary:hover { background: #2a54c7; border-color: #2a54c7; color: #fff; }
.paper-btn.btn-gh { background: var(--ink); border-color: var(--ink); color: #fff; }
.paper-btn.btn-gh:hover { background: var(--ink-2); border-color: var(--ink-2); color: #fff; }

/* Preprint notice */
.paper-preprint-notice {
  display: flex; align-items: flex-start; gap: 12px;
  padding: 14px 18px;
  border-radius: var(--r-md);
  background: linear-gradient(135deg, rgba(208,136,25,0.07), rgba(59,108,239,0.05));
  border: 1.5px solid var(--amber-med);
  margin-bottom: 36px;
}
.paper-preprint-notice svg { width: 18px; height: 18px; flex-shrink: 0; color: var(--amber); stroke: currentColor; fill: none; stroke-width: 2; margin-top: 1px; }
.paper-preprint-notice p { font-size: 0.88rem; color: var(--ink-2); line-height: 1.55; }
.paper-preprint-notice strong { color: var(--amber); }

/* Section layout */
.paper-section { margin-bottom: 44px; }

.paper-section-title {
  font-family: var(--serif);
  font-size: 1.25rem; font-weight: 700;
  letter-spacing: -0.02em; color: var(--ink);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
  position: relative;
}
.paper-section-title::after {
  content: '';
  position: absolute; bottom: -1px; left: 0;
  width: 40px; height: 2px;
  background: linear-gradient(90deg, var(--blue), var(--green));
  border-radius: 1px;
}

/* Abstract */
.paper-abstract {
  font-family: var(--serif);
  font-size: 1rem; line-height: 1.75;
  color: var(--ink-2);
  padding: 22px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-xs);
  border-left: 3px solid var(--blue);
}
.paper-abstract p + p { margin-top: 12px; }
.paper-abstract .method-name {
  font-variant: small-caps;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--blue);
}

/* Figures */
.paper-figure-full { display: block; margin: 0; }
.paper-figure-full img {
  width: 100%; display: block;
  border-radius: var(--r-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  background: var(--surface);
}
.paper-figure-full figcaption {
  margin-top: 10px;
  font-size: 0.82rem; color: var(--ink-3); line-height: 1.5;
  text-align: center;
}
/* Constrained figure (for portrait / small diagrams) */
.paper-figure-sm {
  max-width: 420px;
  margin-left: auto; margin-right: auto;
}
.paper-figure-sm img { border-radius: var(--r-md); box-shadow: var(--shadow-sm); }

/* Side-by-side figure row */
.paper-figures-row {
  display: grid; grid-template-columns: 1fr 1fr; gap: 20px;
}
.paper-figures-row figure { margin: 0; }
.paper-figures-row figure img {
  width: 100%; border-radius: var(--r-md);
  border: 1px solid var(--border); box-shadow: var(--shadow-sm);
  background: var(--surface);
}
.paper-figures-row figcaption {
  margin-top: 8px; font-size: 0.78rem;
  color: var(--ink-3); line-height: 1.45; text-align: center;
}

/* Highlights */
.paper-highlights {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px;
}
.paper-highlight {
  display: block;
  padding: 20px 16px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--r-lg); box-shadow: var(--shadow-xs);
  text-align: center;
  position: relative; overflow: hidden;
  text-decoration: none; color: inherit; cursor: pointer;
  transition: transform 0.28s cubic-bezier(0.22,1,0.36,1), box-shadow 0.28s, border-color 0.2s;
}
.paper-highlight:hover { text-decoration: none; border-color: var(--blue-med); }
.paper-highlight:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
}
.paper-highlight::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--blue), var(--green));
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.32s cubic-bezier(0.22,1,0.36,1);
}
.paper-highlight:hover { transform: translateY(-3px); box-shadow: 0 8px 28px rgba(0,0,0,0.07); }
.paper-highlight:hover::before { transform: scaleX(1); }
.ph-num {
  display: block; font-family: var(--serif);
  font-size: 2rem; font-weight: 700;
  letter-spacing: -0.03em; color: var(--blue);
  margin-bottom: 4px; line-height: 1;
}
.ph-lab { display: block; font-size: 0.78rem; color: var(--ink-3); }

/* Method pipeline */
.paper-method { display: grid; gap: 10px; }
.paper-step {
  display: flex; gap: 16px; align-items: flex-start;
  padding: 16px 18px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--r-lg); box-shadow: var(--shadow-xs);
  transition: border-color 0.2s, transform 0.22s cubic-bezier(0.22,1,0.36,1), box-shadow 0.2s;
}
.paper-step:hover { border-color: var(--blue-med); transform: translateX(4px); box-shadow: var(--shadow-sm); }
.paper-step-num {
  flex-shrink: 0;
  width: 28px; height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue), #5b8af8);
  color: #fff;
  font-size: 0.78rem; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
  margin-top: 1px;
}
.paper-step-content { flex: 1; }
.paper-step-content h4 {
  font-family: var(--serif); font-size: 0.95rem;
  font-weight: 600; color: var(--ink); margin-bottom: 3px;
}
.paper-step-content p {
  font-size: 0.84rem; color: var(--ink-3);
  line-height: 1.55; margin: 0;
}
.paper-step-content code {
  font-family: var(--mono); font-size: 0.78rem;
  background: var(--bg-alt); color: var(--ink-2);
  padding: 1px 5px; border-radius: 4px;
}

/* Experiment blocks (stacked) */
.paper-exp-block {
  margin-bottom: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: 72px;
}
.paper-exp-block:last-child { margin-bottom: 0; padding-bottom: 0; border-bottom: none; }

/* Briefly flash a target on anchor jump */
.paper-exp-block:target {
  animation: target-flash 1.6s ease-out 1;
}
@keyframes target-flash {
  0%   { background: var(--blue-soft); }
  100% { background: transparent; }
}
.paper-exp-title {
  font-family: var(--serif); font-size: 1.05rem; font-weight: 600;
  color: var(--ink); margin-bottom: 8px; letter-spacing: -0.01em;
}
.paper-exp-desc {
  font-size: 0.88rem; color: var(--ink-3); line-height: 1.65;
  margin-bottom: 16px;
}
.paper-exp-desc strong { color: var(--ink-2); }
.paper-exp-desc a { color: var(--blue); }

/* Results table */
.paper-results-table {
  width: 100%; border-collapse: collapse; margin-top: 16px;
  font-size: 0.82rem;
}
.paper-results-table th {
  background: var(--surface-hi);
  color: var(--ink-2); font-weight: 600;
  padding: 8px 10px; border: 1px solid var(--border);
  text-align: center; white-space: nowrap;
}
.paper-results-table th.col-group {
  background: var(--blue-soft); color: var(--blue);
  font-size: 0.8rem; letter-spacing: 0.02em;
}
.paper-results-table td {
  padding: 7px 10px; border: 1px solid var(--border);
  text-align: center; color: var(--ink);
}
.paper-results-table tr.row-base td { color: var(--ink-3); }
.paper-results-table tr.row-ours td { font-weight: 600; background: var(--blue-soft); }
.paper-results-table td.setting,
.paper-results-table th.setting {
  text-align: left; font-weight: 500; white-space: nowrap;
}
.paper-results-table .best { color: var(--blue); font-weight: 700; }
/* Highlighted column (e.g., "Combined" in the PBMC table) */
.paper-results-table col.col-best { background: var(--blue-soft); }
.paper-results-table th.th-best {
  background: linear-gradient(180deg, var(--blue-soft), var(--blue-med)) !important;
  color: var(--blue) !important;
  font-weight: 700; letter-spacing: 0.02em;
}
.paper-results-table td.td-best {
  color: var(--blue) !important; font-weight: 700;
  background: rgba(59,108,239,0.04);
}
.paper-results-table tr.row-ours td.td-best { background: var(--blue-med); }
.paper-results-table-wrap {
  overflow-x: auto; margin-top: 16px;
  border-radius: var(--r-md); border: 1px solid var(--border);
}
.paper-results-table-wrap .paper-results-table { margin-top: 0; }
.paper-results-table-caption {
  margin-top: 10px; font-size: 0.8rem; color: var(--ink-3);
  line-height: 1.5; text-align: center;
}

/* Footer */
.paper-footer {
  margin-top: 56px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 0.78rem; color: var(--ink-4);
  text-align: center;
}
.paper-footer a { color: var(--ink-3); }
.paper-footer a:hover { color: var(--blue); }

/* ═══════════════════════════ RESPONSIVE ═══════════════════════════ */
@media (max-width: 900px) {
  .paper-highlights { grid-template-columns: repeat(2, 1fr); }
  .paper-figures-row { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .page { padding: 14px 12px 36px; }
  .badge-venue { display: none; }
  .paper-highlights { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .page { padding: 12px 10px 28px; }
  .paper-title { font-size: 1.4rem; }
  .paper-highlights { grid-template-columns: repeat(2, 1fr); }
  .ph-num { font-size: 1.5rem; }
  .logo-text { display: none; }
}