/* Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html,
body {
  width: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #fff;
  counter-reset: figure table algorithm;
}

/* Dark / light modes */
body.dark-mode {
  background-color: #000000;
  color: #ffffff;
}

body.light-mode {
  background-color: #ffffff;
  color: #000000;
}

/* Links */
a {
  text-decoration: none;
  transition: color 0.3s ease;
}

body.dark-mode a {
  color: #aaaaaa;
}

body.light-mode a {
  color: #555555;
}

a:hover {
  color: #ffffff;
}

/* Header */
.header {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  position: relative;
  text-align: center;
  background-color: #000;
  color: #fff;
}

/* Hero banner */
.promo-banner {
  background: #f8f9fa;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  min-height: 100vh;
  justify-content: center;
  align-items: center;
  position: relative;
  color: white;
  transition: background 0.3s ease;
}

body.light-mode .promo-banner {
  background: #f8f9fa;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  min-height: 100vh;
  justify-content: center;
  align-items: center;
  position: relative;
  color: white;
  transition: background 0.3s ease;
}

/* Header title */
.header h1 {
  font-size: 3.5rem;
  font-weight: 700;
  color: #ffffff;
  margin: 0;
  z-index: 1;
  text-shadow: none;
}

/* Scroll bar */
.scroll-bar {
  position: absolute;
  bottom: 5vh;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  width: max(5vw, 60px);
  height: max(1vh, 8px);
  background-color: rgba(255, 255, 255, 0.15);
  border-radius: 50px;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.scroll-bar::after {
  content: "";
  display: block;
  width: max(3vw, 40px);
  height: max(0.5vh, 3px);
  background-color: rgba(255, 255, 255, 0.7);
  border-radius: 50px;
  animation: pulse 1.8s infinite;
  transition: background-color 0.3s ease;
}

body.light-mode .scroll-bar {
  background-color: rgba(0, 0, 0, 0.15);
}

body.light-mode .scroll-bar::after {
  background-color: rgba(0, 0, 0, 0.7);
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
    transform: translateY(0);
  }
  50% {
    opacity: 0.5;
    transform: translateY(max(0.8vh, 8px));
  }
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  height: 60px;
  display: flex;
  justify-content: center;
  background-color: transparent;
  color: inherit;
  padding: 0 20px;
  z-index: 1000;
  transition: background-color 0.3s ease;
}

.navbar-content {
  width: 100%;
  max-width: 1200px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

body.dark-mode .navbar {
  background-color: rgba(0, 0, 0, 0.8);
}

body.light-mode .navbar {
  background-color: rgba(255, 255, 255, 0.8);
}

/* Context bar */
.context-bar {
  position: sticky;
  top: 80px;
  width: 300px;
  padding-right: 20px;
  max-height: calc(100vh - 80px);
  overflow: auto;
}

.context-bar ul {
  list-style: none;
  padding: 0;
  margin: 0;
  background-color: #fff;
  border-radius: 8px;
  padding: 10px;
}

.context-bar ul li {
  margin: 10px 0;
}

.context-bar ul li a {
  font-size: 1rem;
  padding: 10px;
  text-decoration: none;
  color: #000;
  border-radius: 4px;
  display: block;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.context-bar ul li a:hover {
  background-color: #444;
  color: #fff;
}

/* Placeholder */
.content-placeholder {
  width: 250px;
  visibility: hidden;
}

/* Main content layout */
.content {
  margin: 0 auto;
  display: flex;
  margin-top: 60px;
  min-height: calc(100vh - 60px);
  align-items: flex-start;
  max-width: 1200px;
  padding: 0 2rem;
  width: 100%;
}

.content-section {
  flex: 1;
  width: 100%;
}

.content-section section {
  scroll-margin-top: 80px;
}

.content-section h2 {
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 20px;
}

.content-section p {
  font-size: 1.2rem;
  line-height: 1.8;
  margin-bottom: 40px;
}

/* Mode toggle */
.mode-toggle {
  font-size: 1.5rem;
  background: none;
  border: none;
  color: inherit;
  cursor: pointer;
  transition: transform 0.3s ease;
}

.mode-toggle:hover {
  transform: scale(1.2);
}

/* Footer */
.footer {
  text-align: center;
  padding: 20px 10px;
  font-size: 0.9rem;
  color: inherit;
}

.footer a {
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer a:hover {
  color: inherit;
}

/* Section anchor offset */
.section {
  position: relative;
}

/* Header buttons */
.header-buttons {
  margin-top: 20px;
  display: flex;
  gap: 15px;
  justify-content: center;
}

.header-button {
  text-decoration: none;
  font-size: 1rem;
  padding: 10px 25px;
  color: #ffffff !important;
  background-color: transparent;
  border: 2px solid rgba(255, 255, 255, 0.8);
  border-radius: 25px;
  font-weight: 500;
  transition: background-color 0.3s ease, transform 0.2s ease,
    border-color 0.3s ease;
}

.header-button:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 1);
  transform: translateY(-2px);
}

/* Byline */
.byline {
  margin: 40px 20px;
  padding: 20px;
  background-color: inherit;
  border-radius: 10px;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.byline-container {
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
  max-width: 1200px;
  width: 100%;
  justify-content: space-around;
}

.byline-column {
  flex: 1;
  min-width: 200px;
}

.byline-column h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 15px;
  color: inherit;
}

.byline-column p {
  margin: 8px 0;
  font-size: 1rem;
  color: inherit;
}

.author-link,
.affiliation-link {
  text-decoration: none;
  font-weight: 500;
  color: inherit;
  transition: color 0.3s ease;
}

.author-link:hover,
.affiliation-link:hover {
  color: #ffd700;
}

.byline-column p sup {
  font-size: 0.8rem;
  vertical-align: top;
  margin-left: 5px;
  color: #aaaaaa;
}

/* Double column layout */
.double-column {
  --left-width: 0.5;
  display: grid;
  grid-template-columns: minmax(0, calc(var(--left-width) * 100%))
    minmax(0, calc((1 - var(--left-width)) * 100%));
  gap: 2rem;
  margin: 2rem 0;
  max-width: 100%;
}

.double-column .left-column,
.double-column .right-column {
  width: 100%;
}

/* Card */
.card {
  --card-padding: 1.5rem;
  --card-radius: 12px;
  position: relative;
  border-radius: var(--card-radius);
  padding: var(--card-padding);
  overflow: hidden;
  background-color: #ffffff;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  min-height: 100px;
  display: flex;
  flex-direction: column;
}

.card-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

.card-content {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: inherit;
}

.card-body {
  flex: 1;
}

.card.dark-theme {
  color: #ffffff;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

.card-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.4));
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: 0;
}

.card.dark-theme .card-overlay {
  opacity: 1;
}

/* Flip card */
.flip-container {
  position: relative;
  width: 100%;
  perspective: 1000px;
}

.flip-inner {
  position: relative;
  width: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}

.flip-container:hover .flip-inner {
  transform: rotateY(180deg);
}

.flip-front,
.flip-back {
  width: 100%;
  backface-visibility: hidden;
  border-radius: var(--card-radius);
}

.flip-front img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--card-radius);
}

.flip-back {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  transform: rotateY(180deg);
  display: flex;
  align-items: center;
  justify-content: center;
  background: #ffffff;
}

.flip-back img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  border-radius: var(--card-radius);
  background: #ffffff;
}

.head-content {
  font-size: 1.1rem;
  color: #444;
  max-width: 1500px;
}

.kw {
  color: #2563eb;
}

/* Banner bar at top */
.banner {
  position: fixed;
  top: 0;
  width: 100%;
  background-color: #fff;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  z-index: 1000;
}

.banner .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.nav-title h1 {
  font-size: 1.5rem;
  font-weight: 600;
  color: #333;
}

/* Containers */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  width: 100%;
}

/* Main */
main {
  margin-top: 80px;
}

/* Section spacing tweaks */
.section p,
.section ul {
  margin-block-start: 0;
  margin-block-end: 0.5rem;
}

/* Figures */
.figure {
  margin: 1.5rem 0;
  text-align: center;
}

.figure img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
}

.figure .caption {
  margin-top: 0.5rem;
  font-size: 0.9rem;
  color: #999;
}

.figure .caption::before {
  counter-increment: figure;
  content: "Figure " counter(figure) ": ";
  font-weight: 500;
}

.ref-list {
  font-size: 0.9rem;
  line-height: 1.5;
  list-style-type: decimal;
  margin-left: 1.5rem;
  margin-top: 0.5rem;
}

.ref-list li {
  margin-bottom: 0.35rem;
}

/* Tables */
.table {
  margin: 1.5rem 0;
  text-align: center;
  overflow-x: auto;
}

.table table {
  margin: 0 auto;
  border-collapse: collapse;
  font-size: 0.85rem;
  max-width: 100vh;
}

.table table th,
.table table td {
  padding: 0.25rem 0.6rem;
  border-bottom: 1px solid #eee;
  white-space: nowrap;
}

.table table tr.section-header th {
  padding-top: 0.6rem;
  padding-bottom: 0.2rem;
  border-bottom: none;
  text-align: left;
  font-weight: 600;
}

.table .caption {
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
  color: #999;
}

.table .caption::before {
  counter-increment: table;
  content: "Table " counter(table) ": ";
  font-weight: 500;
}

/* Algorithm block */
.algorithm {
  margin: 1.5rem 0;
  text-align: center;
}

.algorithm .caption {
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
  color: #777;
}

.algorithm .caption::before {
  counter-increment: algorithm;
  content: "Algorithm " counter(algorithm) ": ";
  font-weight: 500;
}

.algorithm pre {
  margin: 0;
  padding: 0;
  display: inline-block;
  text-align: left;
  background: none;
  border: none;
  white-space: pre;
  overflow-x: auto;
  font-family: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  font-size: 0.85rem;
}

.algorithm code {
  font-family: inherit;
}

.algorithm .alg-comment {
  color: #3a9696;
}

.algorithm .alg-keyword {
  color: #c0265b;
  font-weight: 600;
}

.algorithm .alg-func {
  color: #0057b7;
}

.algorithm .alg-builtin {
  color: #8b5cf6;
}

/* BibTeX block */
.bibtex {
  font-family: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  font-size: 0.8rem;
  background: #fafafa;
  border-radius: 0.5rem;
  padding: 0.75rem 1rem;

  white-space: pre-wrap;
  word-break: break-word;
  max-width: 100%;
  overflow-x: hidden;
}

.footer .bibtex {
  text-align: left;
  display: inline-block;
  margin: 0.5rem auto;
}

.footer .ref-list {
  text-align: left;
  display: inline-block;
  margin: 0.5rem auto;
}

/* Wide screens */
@media (min-width: 1200px) {
  .container {
    max-width: 1200px;
  }
  .content {
    max-width: 1200px;
  }
}

@media (max-width: 1200px) {
  .context-bar {
    display: none;
  }
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2rem;
  }

  .navbar {
    flex-direction: column;
    height: auto;
  }

  .context-bar {
    display: none;
  }

  .content {
    flex-direction: column;
    padding: 0 1.5rem;
  }

  .content-placeholder {
    display: none;
  }

  .footer {
    font-size: 0.8rem;
  }

  .navbar-content {
    max-width: none;
    width: 100%;
  }

  .double-column {
    grid-template-columns: 1fr;
    gap: 1rem;
    max-height: none !important;
  }

  .head-content {
    font-size: 1rem;
    padding: 0 2rem;
  }

  .card {
    width: 100%;
  }
}

/* Phones / portrait-specific tweaks */
@media (max-width: 768px), (orientation: portrait) {
  .promo-banner,
  .header {
    min-height: 100vh;
    height: auto;
  }
}

/* Mobile nav + overlay (kept from original) */
@media (max-width: 768px) {
  .banner {
    padding: 0;
  }

  .menu-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -300px;
    width: 300px;
    height: 100vh;
    background-color: white;
    flex-direction: column;
    padding: 80px 2rem 2rem;
    gap: 2rem;
    transition: right 0.3s ease;
    z-index: 999;
  }

  .nav-links.active {
    right: 0;
  }

  .overlay.active {
    display: block;
  }

  .menu-toggle.active span:first-child {
    transform: rotate(45deg) translate(6px, 6px);
  }

  .menu-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .menu-toggle.active span:last-child {
    transform: rotate(-45deg) translate(6px, -6px);
  }

  main {
    padding: 1rem;
  }
}

@media (max-width: 900px), (orientation: portrait) {
  .algorithm pre {
    font-size: 0.6rem;
  }
  .table table th,
  .table table td {
    white-space: normal;
  }
  .table table {
    width: 100%;
  }
}