/* ============================================================
   Cyber green personal site
   ============================================================ */

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --color-bg: #080808;
  --color-bg-alt: #0c0d0c;
  --color-surface: #101210;
  --color-text: #ffffff;
  --color-text-light: #e0e0e0;
  --color-heading: #4ae04a;
  --color-accent: #4ae04a;
  --color-accent-dim: #2e7d3a;
  --color-link: #b07adb;
  --color-border: #1a2a1a;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, monospace;
  --max-width: 860px;
  --radius: 5px;
  --transition: 0.25s ease;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--color-link);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: #c9a0ee;
  text-decoration: underline;
}

img {
  max-width: 100%;
  height: auto;
}

::selection {
  background: var(--color-accent-dim);
  color: #fff;
}

/* ---------- Navigation ---------- */
nav {
  padding: 1.5rem 1.5rem 0.5rem;
  text-align: center;
}

nav ul {
  list-style: none;
  display: inline-flex;
  gap: 0;
  flex-wrap: wrap;
  justify-content: center;
}

nav ul li a {
  display: block;
  color: var(--color-heading);
  padding: 0.4rem 1.2rem;
  font-size: 0.95rem;
  font-style: italic;
  font-weight: 600;
  border: 1.5px solid var(--color-heading);
  transition: background var(--transition), color var(--transition);
  text-decoration: none;
}

nav ul li a:hover {
  background: rgba(74, 224, 74, 0.1);
  text-decoration: none;
}

/* ---------- Main Content (two-column) ---------- */
.content {
  max-width: var(--max-width);
  margin: 2rem auto 0;
  padding: 0 1.5rem;
  display: flex;
  gap: 2rem;
  align-items: flex-start;
}

/* ---------- Sidebar (photo + social) ---------- */
.sidebar {
  flex-shrink: 0;
  width: 200px;
}

.sidebar .profile-photo {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  display: block;
  margin-bottom: 1rem;
}

.sidebar .social-links {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.sidebar .social-links a {
  color: var(--color-text);
  font-size: 0.92rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.15rem 0;
  text-decoration: none;
}

.sidebar .social-links a:hover {
  color: #7ef28b;
  text-decoration: none;
}

.sidebar .social-links a i {
  font-size: 0.9rem;
  width: 1.1rem;
  text-align: center;
}

/* ---------- Main Body ---------- */
.main-body {
  flex: 1;
  min-width: 0;
}

.main-body h1 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.6rem;
  color: var(--color-heading);
  margin-bottom: 0.8rem;
}

.main-body h2 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.05rem;
  font-style: italic;
  color: var(--color-heading);
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.main-body p {
  font-style: italic;
  font-weight: 600;
  margin-bottom: 0.9rem;
}

.main-body ul {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0.5rem;
}

.main-body ul li {
  padding-left: 0;
  margin-bottom: 0.2rem;
  font-weight: 500;
}

.main-body ul li::before {
  content: "✳ ";
}

/* ---------- Page Header (sub-pages) ---------- */
.page-header {
  background: var(--color-bg);
  color: var(--color-text);
  padding: 3rem 1.5rem 1.5rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.page-header h1 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.6rem;
  color: var(--color-heading);
  margin-bottom: 0.25rem;
  letter-spacing: -0.025em;
}

.page-header p {
  color: var(--color-text-light);
  font-size: 0.92rem;
}

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

section {
  padding: 2.5rem 0;
}

section h2 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--color-heading);
  margin-bottom: 1.25rem;
  padding-bottom: 0.45rem;
  border-bottom: 1px solid var(--color-border);
  display: block;
  letter-spacing: -0.02em;
}

/* ---------- Fade-in animation ---------- */
.fade-in-section {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.65s ease-out, transform 0.65s ease-out;
}

.fade-in-section.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- About ---------- */
.about-content .bio p {
  margin-bottom: 1rem;
}

.bio-quote {
  margin-top: 1.25rem;
  padding: 0.85rem 1.15rem;
  border-left: 2px solid var(--color-accent-dim);
  color: var(--color-text-light);
  font-style: italic;
  font-size: 0.92rem;
  background: var(--color-surface);
  border-radius: 0 var(--radius) var(--radius) 0;
}

/* ---------- Publications Page – Cards ---------- */
.pub-filters {
  padding: 1.5rem 0 0;
  max-width: var(--max-width);
  margin: 0 auto;
}

.filter-bar {
  display: flex;
  gap: 0.45rem;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: transparent;
  color: var(--color-text-light);
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}

.filter-btn:hover {
  border-color: var(--color-accent-dim);
  color: var(--color-accent);
}

.filter-btn.active {
  background: var(--color-accent-dim);
  border-color: var(--color-accent-dim);
  color: #fff;
}

.pub-list-section {
  padding: 1.5rem 0 3rem;
}

.pub-year-heading {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--color-text-light);
  margin: 2rem 0 0.75rem;
  padding-bottom: 0.3rem;
  border-bottom: 1px solid var(--color-border);
}

.pub-year-heading:first-child {
  margin-top: 0;
}

.publication-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.15rem;
  margin-bottom: 0.65rem;
  position: relative;
  transition: border-color var(--transition);
}

.publication-card:hover {
  border-color: #252a25;
}

.pub-type-badge {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.12rem 0.45rem;
  border-radius: var(--radius);
  margin-bottom: 0.35rem;
}

.pub-type-badge.conference {
  background: rgba(92, 219, 111, 0.12);
  color: var(--color-accent);
}

.pub-type-badge.journal {
  background: rgba(100, 160, 210, 0.12);
  color: #6aa0d2;
}

.pub-type-badge.preprint {
  background: rgba(200, 180, 100, 0.12);
  color: #c0a850;
}

.pub-title {
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-heading);
  margin-bottom: 0.12rem;
}

.pub-authors {
  color: var(--color-text-light);
  font-size: 0.85rem;
}

.pub-venue {
  font-style: italic;
  font-size: 0.82rem;
  color: var(--color-text-light);
  margin-bottom: 0.35rem;
}

.pub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.pub-links a {
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.18rem 0.45rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

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

.pub-links a i {
  margin-right: 0.15rem;
}

/* ---------- Blog Listing ---------- */
.blog-listing {
  padding: 2rem 0 3rem;
}

.blog-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.15rem 1.25rem;
  margin-bottom: 0.65rem;
  transition: border-color var(--transition);
}

.blog-card:hover {
  border-color: #252a25;
}

.blog-card-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-bottom: 0.35rem;
  font-size: 0.78rem;
}

.blog-date {
  color: var(--color-text-light);
  font-size: 0.76rem;
}

.blog-tag {
  background: var(--color-accent-dim);
  color: #c0d4c4;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.08rem 0.4rem;
  border-radius: var(--radius);
}

.blog-card h2 {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--color-heading);
  margin-bottom: 0.25rem;
  border: none;
  padding-bottom: 0;
  display: block;
}

.blog-card h2 a {
  color: var(--color-heading);
}

.blog-card h2 a:hover {
  color: var(--color-accent);
  text-decoration: none;
}

.blog-card p {
  color: var(--color-text-light);
  font-size: 0.88rem;
  margin-bottom: 0.35rem;
}

.read-more {
  font-weight: 600;
  font-size: 0.8rem;
}

/* ---------- Loading ---------- */
.loading-msg {
  text-align: center;
  padding: 2rem;
  color: var(--color-text-light);
  font-size: 0.88rem;
}

/* ---------- Blog Post ---------- */
.blog-post {
  padding: 2.5rem 0;
}

.post-header {
  margin-bottom: 2rem;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-bottom: 0.55rem;
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.post-header h1 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.65rem;
  color: var(--color-heading);
  line-height: 1.3;
  letter-spacing: -0.025em;
}

.post-body h2 {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--color-heading);
  margin: 2rem 0 0.55rem;
  border: none;
  padding-bottom: 0;
  display: block;
}

.post-body p {
  margin-bottom: 1rem;
}

.post-body code {
  font-family: var(--font-mono);
  background: var(--color-surface);
  padding: 0.12rem 0.3rem;
  border-radius: 3px;
  font-size: 0.86em;
  color: var(--color-accent);
}

.post-body pre {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem;
  overflow-x: auto;
  margin-bottom: 1rem;
}

.post-body pre code {
  background: none;
  padding: 0;
}

.post-body ul, .post-body ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.post-body li {
  margin-bottom: 0.25rem;
}

.post-nav {
  margin-top: 2.5rem;
  padding-top: 1.15rem;
  border-top: 1px solid var(--color-border);
}

.post-nav a {
  font-weight: 600;
  font-size: 0.82rem;
}

/* ---------- Section CTA ---------- */
.section-cta {
  margin-top: 1.15rem;
}

/* ---------- Teaching ---------- */
.teaching-item {
  margin-bottom: 0.65rem;
  padding: 0.75rem 1rem;
  border-left: 2px solid var(--color-accent-dim);
  background: var(--color-surface);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.teaching-item h3 {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-heading);
  margin-bottom: 0.1rem;
}

.teaching-item .role {
  font-style: italic;
  color: var(--color-text-light);
  font-size: 0.82rem;
}

.teaching-item p {
  font-size: 0.85rem;
  color: var(--color-text-light);
}

/* ---------- Button ---------- */
.btn {
  display: inline-block;
  padding: 0.4rem 0.95rem;
  background: transparent;
  color: var(--color-accent);
  border: 1px solid var(--color-accent-dim);
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.82rem;
  transition: all var(--transition);
}

.btn:hover {
  background: var(--color-accent-dim);
  color: #fff;
  text-decoration: none;
}

/* ---------- Contact ---------- */
.contact-info {
  font-size: 0.88rem;
  color: var(--color-text-light);
}

.contact-info a {
  font-size: 0.85rem;
}

/* ---------- Footer ---------- */
footer {
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-light);
  text-align: center;
  padding: 1.5rem 1rem;
  font-size: 0.78rem;
  max-width: var(--max-width);
  margin: 2rem auto 0;
}

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

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

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
  nav ul {
    flex-wrap: wrap;
    justify-content: center;
  }

  .content {
    flex-direction: column;
    align-items: center;
  }

  .sidebar {
    width: 160px;
    text-align: center;
  }

  .sidebar .profile-photo {
    width: 160px;
  }

  .sidebar .social-links {
    align-items: center;
  }

  .main-body h1 {
    font-size: 1.4rem;
  }

  .page-header h1 {
    font-size: 1.4rem;
  }
}