:root {
  --ink: #142326;
  --muted: #5e6f73;
  --soft: #eef4f2;
  --paper: #fbfcf9;
  --line: #d9e3df;
  --accent: #0f8b8d;
  --accent-dark: #0a5f61;
  --gold: #d59f2f;
  --coral: #c85f44;
  --panel: #ffffff;
  --shadow: 0 18px 50px rgba(20, 35, 38, 0.12);
  --shadow-soft: 0 10px 30px rgba(20, 35, 38, 0.08);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  margin: 0;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

a {
  color: inherit;
}

img,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

button {
  font: inherit;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 20;
  padding: 0.6rem 0.8rem;
  background: var(--ink);
  color: white;
  border-radius: 6px;
}

.skip-link:focus {
  top: 1rem;
}

.topbar {
  width: min(var(--max), calc(100% - 36px));
  margin: 0 auto;
  padding: 22px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
}

.brand {
  font-weight: 900;
  letter-spacing: 0;
  text-decoration: none;
  color: var(--ink);
}

.nav-links {
  display: flex;
  gap: 22px;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--muted);
}

.nav-links a {
  text-decoration: none;
}

.nav-links a:hover {
  color: var(--ink);
}

.site-hero {
  color: var(--ink);
  background: #f4f5f3;
  overflow: hidden;
}

.hero-content {
  width: min(1040px, calc(100% - 36px));
  margin: 0 auto;
  padding: 42px 0 30px;
  text-align: center;
}

.eyebrow {
  margin: 0 0 10px;
  color: #b98512;
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.hero-content h1 {
  margin: 0 auto 22px;
  max-width: 1040px;
  font-size: clamp(1.95rem, 4vw, 4.05rem);
  line-height: 1.04;
  letter-spacing: 0;
  font-weight: 900;
  color: var(--ink);
}

.authors {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px 20px;
  margin: 0 auto 8px;
  color: var(--ink);
  font-weight: 700;
}

.affiliations {
  margin: 0 auto 24px;
  max-width: 780px;
  color: var(--muted);
  font-weight: 500;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

.button {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 0.72rem 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  color: var(--ink);
  text-decoration: none;
  font-weight: 800;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
  background: white;
  border-color: var(--accent);
}

.button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

.button.primary:hover {
  background: #11a1a3;
}

.button.disabled {
  cursor: not-allowed;
  opacity: 0.76;
}

.hero-media {
  width: min(600px, calc(100% - 36px));
  margin: 24px auto 0;
  padding: 10px;
  background: rgba(255, 255, 255, 0.98);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.hero-media img {
  width: 100%;
  border-radius: 5px;
}

figcaption {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.45;
}

.hero-media figcaption {
  padding: 12px 8px 3px;
  text-align: center;
}

.section {
  width: min(var(--max), calc(100% - 36px));
  margin: 0 auto;
  padding: 96px 0;
}

.abstract-section {
  padding-top: 72px;
}

.section-heading {
  margin-bottom: 26px;
  max-width: 860px;
}

.section-heading h2,
.principle-section h2,
.citation-header h2 {
  margin: 0;
  font-size: clamp(1.85rem, 3vw, 3.1rem);
  line-height: 1.12;
  letter-spacing: 0;
  font-weight: 900;
}

.abstract-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
  gap: 38px;
  align-items: start;
}

.abstract-copy {
  font-size: 1.08rem;
  color: #33474c;
}

.abstract-copy p:first-child {
  margin-top: 0;
}

.abstract-media {
  margin: 0;
  padding: 10px;
  background: rgba(255, 255, 255, 0.98);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
  align-self: start;
}

.abstract-media img {
  width: 100%;
  border-radius: 5px;
}

.abstract-media figcaption {
  padding: 12px 8px 3px;
  text-align: center;
}

.abstract-keywords {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 18px;
}

.abstract-keyword {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 50px;
  padding: 12px 14px;
  background: #ffffff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 8px 20px rgba(20, 35, 38, 0.05);
}

.abstract-keyword i,
.abstract-keyword svg {
  flex: 0 0 auto;
  color: var(--accent);
  font-size: 1.05rem;
}

.abstract-keyword h3 {
  margin: 0;
  font-size: 0.98rem;
  line-height: 1.25;
  font-weight: 900;
}

.core-intuition-card {
  margin-top: 20px;
  padding: 18px;
  background: #eef6f5;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.core-intuition-card h3 {
  margin: 0 0 10px;
  font-size: 1.4rem;
  line-height: 1.2;
}

.core-intuition-card p {
  margin: 0;
}

.core-intuition-figure {
  margin: 16px 0 0;
  padding: 10px;
  background: rgba(255, 255, 255, 0.68);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.core-intuition-figure img {
  width: 100%;
  border-radius: 5px;
}

.core-intuition-figure figcaption {
  margin-top: 10px;
  font-size: 0.9rem;
}

.contribution-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.contribution-grid article,
.stat-card,
.result-table-card,
.equation-card,
.tab-panels,
.framed-figure,
.gallery-item,
.result-media,
.wide-result-item,
.force-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
}

.contribution-grid article {
  padding: 20px;
}

.contribution-grid i,
.contribution-grid svg {
  color: var(--accent);
  font-size: 1.25rem;
}

.contribution-grid h3 {
  margin: 12px 0 6px;
  font-size: 1rem;
}

.contribution-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.5;
}

.principle-section {
  width: 100%;
  max-width: none;
  padding: 86px max(18px, calc((100vw - var(--max)) / 2));
  background: var(--soft);
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(340px, 1.14fr);
  gap: 42px;
  align-items: center;
}

.result-split {
  align-items: start;
}

.result-subsection {
  margin-top: 42px;
}

.result-copy h3,
.subsection-heading h3 {
  margin: 0 0 12px;
  font-size: 1.6rem;
  line-height: 1.15;
}

.result-copy p {
  margin: 0;
  color: #385056;
  font-size: 1.02rem;
}

.subsection-heading {
  margin-bottom: 18px;
}

.wide-results {
  display: grid;
  gap: 28px;
}

.wide-result-item {
  margin: 0;
  padding: 12px;
}

.wide-result-item img,
.force-card img {
  width: 100%;
  height: auto;
}

.wide-result-item img {
  object-fit: contain;
  background: #f3f6f4;
  border-radius: 5px;
}

.force-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.force-card {
  margin: 0;
  padding: 12px;
  cursor: zoom-in;
  transition: transform 160ms ease, box-shadow 160ms ease;
}

.force-card img {
  aspect-ratio: 4 / 3;
  object-fit: contain;
  background: #f3f6f4;
  border-radius: 5px;
}

.force-card:hover {
  transform: translateY(-2px);
}

.split p:not(.eyebrow) {
  color: #385056;
  font-size: 1.05rem;
}

.framed-figure {
  margin: 0;
  padding: 10px;
}

.framed-figure img {
  border-radius: 5px;
}

.framed-figure figcaption,
.gallery-item figcaption {
  padding: 12px 4px 2px;
}

.method-layout {
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr);
  gap: 18px;
  align-items: stretch;
}

.tabs {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.tab,
.gallery-filter,
.copy-bibtex-btn {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  color: var(--ink);
  cursor: pointer;
  font-weight: 800;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease, transform 160ms ease;
}

.tab {
  min-height: 50px;
  padding: 0 16px;
  text-align: left;
}

.tab:hover,
.gallery-filter:hover,
.copy-bibtex-btn:hover {
  transform: translateY(-1px);
  border-color: var(--accent);
}

.tab.active,
.gallery-filter.active,
.copy-bibtex-btn {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

.tab-panels {
  padding: 30px;
  min-height: 250px;
}

.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
}

.tab-panel h3 {
  margin: 0 0 12px;
  font-size: 1.45rem;
}

.tab-panel p {
  margin: 0;
  color: #385056;
  font-size: 1.04rem;
}

.equation-card {
  margin-top: 18px;
  padding: 18px;
  overflow-x: auto;
}

.equation-card span {
  display: block;
  margin-bottom: 8px;
  color: var(--accent-dark);
  font-weight: 900;
}

.media-section {
  width: 100%;
  max-width: none;
  padding: 86px max(18px, calc((100vw - var(--max)) / 2));
  background: white;
  color: var(--ink);
}

.media-section .section-heading {
  color: var(--ink);
}

.video-shell {
  padding: 10px;
  background: white;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
}

.video-shell video {
  width: 100%;
  border-radius: 5px;
  background: #0a0f10;
  aspect-ratio: 16 / 9;
}

.media-description {
  padding: 18px 12px 8px;
}

.media-description h3 {
  margin: 0 0 8px;
  font-size: 1.15rem;
  line-height: 1.25;
  font-weight: 900;
  color: var(--ink);
}

.media-description p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.6;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-bottom: 28px;
}

.stat-card {
  padding: 22px;
}

.stat-card strong {
  display: block;
  color: var(--accent-dark);
  font-size: 2.25rem;
  line-height: 1;
  letter-spacing: 0;
}

.stat-card span {
  display: block;
  margin-top: 10px;
  color: var(--muted);
  font-weight: 600;
  font-size: 0.94rem;
}

.gallery-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-bottom: 18px;
}

.gallery-filter {
  min-height: 38px;
  padding: 0 14px;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.gallery-item {
  margin: 0;
  padding: 10px;
}

.gallery-item[hidden] {
  display: none;
}

.gallery-item img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: #f4f7f5;
  border-radius: 5px;
}

.gallery-item figcaption strong {
  color: var(--ink);
}

.table-section {
  padding-top: 18px;
}

.table-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.results-footnote {
  grid-column: 1 / -1;
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.results-footnote a {
  color: var(--accent-dark);
  font-weight: 800;
}

.modal-overlay {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(10, 20, 22, 0.82);
  z-index: 1000;
}

.modal-overlay.is-open {
  display: flex;
}

.modal-dialog {
  position: relative;
  width: min(1040px, 100%);
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.modal-dialog img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: contain;
  background: #f4f7f5;
}

.modal-caption {
  padding: 14px 16px 16px;
  color: var(--muted);
  font-size: 0.95rem;
}

.modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 40px;
  height: 40px;
  border: 0;
  border-radius: 50%;
  background: white;
  color: var(--ink);
  cursor: pointer;
  box-shadow: var(--shadow-soft);
}

.result-table-card {
  padding: 22px;
}

.result-table-card h3 {
  margin: 0 0 14px;
}

.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 560px;
  font-size: 0.92rem;
}

th,
td {
  padding: 11px 10px;
  border-bottom: 1px solid var(--line);
  text-align: left;
}

th {
  color: var(--muted);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

tr.highlight td {
  background: #eef8f7;
  font-weight: 800;
}

.citation-section {
  padding-top: 72px;
}

.citation-header {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: end;
  margin-bottom: 16px;
}

.copy-bibtex-btn {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0 14px;
}

.copy-bibtex-btn.copied {
  background: #237047;
  border-color: #237047;
}

pre {
  margin: 0;
  padding: 22px;
  overflow-x: auto;
  color: #dce9e5;
  background: #102025;
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.92rem;
  line-height: 1.6;
}

.site-footer {
  padding: 42px 18px;
  text-align: center;
  color: var(--muted);
  background: #edf3f0;
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin: 5px auto;
  max-width: 760px;
}

.site-footer a {
  color: var(--accent-dark);
  font-weight: 800;
}

.scroll-to-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 10;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border: 0;
  border-radius: 50%;
  color: white;
  background: var(--accent);
  box-shadow: var(--shadow-soft);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 160ms ease, transform 160ms ease;
}

.scroll-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

@media (max-width: 980px) {
  .abstract-grid,
  .split,
  .table-grid {
    grid-template-columns: 1fr;
  }

  .method-layout {
    grid-template-columns: 1fr;
  }

  .tabs {
    flex-direction: row;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .tab {
    flex: 0 0 auto;
    min-width: 170px;
  }

  .stats-grid,
  .force-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 700px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav-links {
    width: 100%;
    gap: 12px;
    overflow-x: auto;
    font-size: 0.85rem;
  }

  .hero-content {
    padding-top: 18px;
  }

  .hero-content h1 {
    font-size: 1.95rem;
  }

  .button {
    width: 100%;
  }

  .hero-media {
    width: min(100%, 560px);
    margin-bottom: 0;
  }

  .abstract-section {
    padding-top: 46px;
  }

  .section,
  .principle-section,
  .media-section {
    padding-top: 62px;
    padding-bottom: 62px;
  }

  .contribution-grid,
  .abstract-keywords,
  .stats-grid,
  .force-grid {
    grid-template-columns: 1fr;
  }

  .wide-result-item,
  .force-card {
    padding: 10px;
  }

  .split {
    gap: 20px;
  }

  .tab-panels {
    padding: 22px;
  }

  .citation-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .copy-bibtex-btn {
    width: 100%;
    justify-content: center;
  }
}

.force-card img,
.modal-dialog img {
  aspect-ratio: 4 / 3;
}