/* ===== CSS Reset & Variables ===== */
:root {
  --text-color: #1a1a1a;
  --text-light: #666;
  --bg-color: #ffffff;
  --bg-secondary: #fafafa;
  --accent-color: #0066cc;
  --border-color: #e0e0e0;
  --max-width: 720px;
  --spacing: 1.5rem;
}

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

/* ===== Typography ===== */
html {
  font-size: 16px;
  line-height: 1.6;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  color: var(--text-color);
  background-color: var(--bg-color);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  margin-top: 2rem;
  margin-bottom: 1rem;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }

p {
  margin-bottom: 1rem;
}

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  text-decoration: underline;
}

strong {
  font-weight: 600;
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
  font-size: 0.9em;
  background: var(--bg-secondary);
  padding: 0.2em 0.4em;
  border-radius: 3px;
}

pre {
  background: var(--bg-secondary);
  padding: 1rem;
  border-radius: 4px;
  overflow-x: auto;
  margin-bottom: 1.5rem;
}

pre code {
  background: none;
  padding: 0;
}

/* ===== Layout ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

main {
  min-height: calc(100vh - 200px);
  padding: 3rem 0;
}

/* ===== Navigation ===== */
.navbar {
  border-bottom: 1px solid var(--border-color);
  padding: 1.5rem 0;
  background: var(--bg-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-color);
  text-decoration: none;
}

.site-title:hover {
  text-decoration: none;
  color: var(--accent-color);
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 2rem;
  margin: 0;
}

.nav-links a {
  color: var(--text-light);
  font-size: 0.95rem;
  position: relative;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent-color);
  text-decoration: none;
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -1.7rem;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-color);
}

/* ===== Home Page ===== */
.home-content h2 {
  font-size: 2rem;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.home-content h3 {
  margin-top: 3rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
}

.home-content ul {
  margin-left: 1.5rem;
  margin-bottom: 1.5rem;
}

.home-content li {
  margin-bottom: 0.5rem;
}

/* ===== Page Header ===== */
.page-header {
  margin-bottom: 3rem;
}

.page-header h1 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.page-header p {
  color: var(--text-light);
  margin-bottom: 0;
}

/* ===== Publications ===== */
.publication {
  margin-bottom: 2.5rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid var(--border-color);
}

.publication:last-child {
  border-bottom: none;
}

.pub-title {
  font-size: 1.15rem;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.pub-title a {
  color: var(--text-color);
}

.pub-title a:hover {
  color: var(--accent-color);
  text-decoration: none;
}

.pub-authors {
  color: var(--text-light);
  font-size: 0.95rem;
  margin-bottom: 0.25rem;
}

.pub-venue {
  color: var(--text-light);
  font-size: 0.9rem;
  font-style: italic;
  margin-bottom: 0.75rem;
}

.pub-description {
  margin-bottom: 1rem;
  line-height: 1.6;
}

.pub-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.pub-link {
  padding: 0.4rem 0.9rem;
  background: var(--bg-secondary);
  color: var(--accent-color);
  border-radius: 3px;
  font-size: 0.85rem;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}

.pub-link:hover {
  background: var(--accent-color);
  color: white;
  text-decoration: none;
  border-color: var(--accent-color);
}

/* ===== Projects ===== */
.project-card {
  margin-bottom: 2.5rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid var(--border-color);
}

.project-card:last-child {
  border-bottom: none;
}

.project-card h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.project-card h3 a {
  color: var(--text-color);
}

.project-card h3 a:hover {
  color: var(--accent-color);
  text-decoration: none;
}

.project-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.project-date {
  color: var(--text-light);
  font-size: 0.9rem;
}

.project-tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.tag {
  padding: 0.25rem 0.6rem;
  background: var(--bg-secondary);
  color: var(--text-light);
  border-radius: 3px;
  font-size: 0.8rem;
  border: 1px solid var(--border-color);
}

.project-links {
  display: flex;
  gap: 0.75rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.project-link {
  padding: 0.4rem 0.9rem;
  background: var(--bg-secondary);
  color: var(--accent-color);
  border-radius: 3px;
  font-size: 0.85rem;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}

.project-link:hover {
  background: var(--accent-color);
  color: white;
  text-decoration: none;
  border-color: var(--accent-color);
}

/* ===== Publication/Project Detail Pages ===== */
.publication-detail h1,
.project-detail h1 {
  margin-top: 0;
  margin-bottom: 1rem;
}

.pub-content,
.project-content {
  margin-top: 2rem;
}

.pub-content h2,
.project-content h2 {
  margin-top: 2.5rem;
}

/* ===== Footer ===== */
footer {
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  margin-top: 4rem;
}

footer p {
  text-align: center;
  color: var(--text-light);
  font-size: 0.9rem;
  margin: 0;
}

footer a {
  color: var(--text-light);
}

footer a:hover {
  color: var(--accent-color);
}

/* ===== Responsive Design ===== */
@media (max-width: 640px) {
  html {
    font-size: 15px;
  }

  .navbar .container {
    flex-direction: column;
    gap: 1rem;
    align-items: flex-start;
  }

  .nav-links {
    gap: 1.5rem;
  }

  .nav-links a.active::after {
    display: none;
  }

  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.35rem; }
  h3 { font-size: 1.15rem; }

  .project-meta {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  main {
    padding: 2rem 0;
  }
}

/* ===== Utilities ===== */
hr {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 2rem 0;
}

blockquote {
  border-left: 3px solid var(--accent-color);
  padding-left: 1rem;
  margin-left: 0;
  color: var(--text-light);
  font-style: italic;
}

img {
  max-width: 100%;
  height: auto;
  border-radius: 4px;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
}

th, td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

th {
  font-weight: 600;
  background: var(--bg-secondary);
}