:root {
  --primary: #f0f0f0;
  --accent: #6eb5e0;
  --accent-dark: #5a9fc9;
  --text: #e0e0e0;
  --text-light: #a0a0a0;
  --bg: #0d0d0d;
  --bg-alt: #1a1a1a;
  --border: #2a2a2a;
  --shadow: 0 2px 12px rgba(0,0,0,0.4);
  --radius: 8px;
  --max-width: 960px;
  --transition: 0.2s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}

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

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Navbar ── */
.navbar {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  background: rgba(13,13,13,0.98);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 60px;
}

.nav-brand {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--primary);
  letter-spacing: -0.02em;
}

.nav-brand:hover {
  color: var(--accent);
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 32px;
}

.nav-links a {
  color: var(--text-light);
  font-size: 0.95rem;
  font-weight: 400;
  padding: 4px 0;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--transition);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-links a.active {
  color: var(--primary);
  font-weight: 500;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: all var(--transition);
}

.nav-brand .nav-emoji {
  margin-right: 6px;
}

/* ── Hero ── */
.hero {
  padding: 64px 0 48px;
}

.hero-content {
  display: flex;
  gap: 48px;
  align-items: flex-start;
}

.hero-text {
  flex: 1;
}

.hero-text h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
  letter-spacing: -0.03em;
}

.tagline {
  color: var(--text-light);
  font-size: 1rem;
  margin-bottom: 24px;
  font-weight: 400;
}

.hero-about p {
  margin-bottom: 16px;
  color: var(--text);
  font-size: 0.95rem;
}

.hero-about strong {
  font-weight: 600;
}

.social-links {
  display: flex;
  gap: 16px;
  margin-top: 24px;
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-alt);
  color: var(--text-light);
  font-size: 1.1rem;
  transition: all var(--transition);
}

.social-links a:hover {
  background: var(--accent);
  color: #0d0d0d;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(110,181,224,0.3);
}

.hero-image {
  flex-shrink: 0;
}

.profile-placeholder {
  width: 220px;
  height: 260px;
  border-radius: var(--radius);
  background: var(--bg-alt);
  border: 2px dashed var(--border);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  gap: 8px;
}

.profile-placeholder i {
  font-size: 3rem;
  opacity: 0.3;
}

.profile-placeholder span {
  font-size: 0.8rem;
  text-align: center;
  opacity: 0.5;
}

.profile-img {
  width: 220px;
  height: 260px;
  object-fit: cover;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ── News ── */
.news-section {
  padding: 48px 0;
  border-top: 1px solid var(--border);
}

.news-section h2 {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.news-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.news-item {
  display: flex;
  gap: 24px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}

.news-item:last-child {
  border-bottom: none;
}

.news-date {
  flex-shrink: 0;
  width: 100px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
}

.news-text {
  font-size: 0.95rem;
  color: var(--text);
}

/* ── Projects Page ── */
.page-header {
  padding: 48px 0 24px;
}

.page-header h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: -0.03em;
}

.page-header p {
  color: var(--text-light);
  margin-top: 8px;
}

/* Project detail page */
.project-page-content {
  padding-bottom: 64px;
  max-width: 720px;
}

.project-page-content p {
  font-size: 0.95rem;
  color: var(--text);
  margin-bottom: 16px;
  line-height: 1.7;
}

.project-page-content h2 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--primary);
  margin-top: 28px;
  margin-bottom: 12px;
}

.project-page-content .project-links {
  margin-top: 28px;
}

.project-page-content .project-figure {
  margin: 20px 0 24px 0;
  max-width: 520px;
  padding-left: 0;
}

.project-page-content .project-figure img {
  width: 100%;
  max-height: 320px;
  height: auto;
  object-fit: contain;
  object-position: top left;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  display: block;
  background: var(--bg-alt);
}

.project-page-content .project-figure figcaption {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-top: 8px;
  font-style: italic;
}

/* Project category sections (Vivek-style) */
.project-category {
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--primary);
  letter-spacing: -0.02em;
  margin-top: 40px;
  margin-bottom: 20px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
}

.project-category:first-of-type {
  margin-top: 0;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 24px;
  padding-bottom: 32px;
}

.projects-grid:last-of-type {
  padding-bottom: 64px;
}

.project-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.project-thumbnail {
  width: 100%;
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: rgba(255,255,255,0.9);
  flex-shrink: 0;
  overflow: hidden;
  position: relative;
}

.project-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.project-thumbnail.agentic { background: linear-gradient(135deg, #4a5568 0%, #2d3748 100%); }
.project-thumbnail.software { background: linear-gradient(135deg, #2b6cb0 0%, #1a365d 100%); }
.project-thumbnail.nlp { background: linear-gradient(135deg, #805ad5 0%, #553c9a 100%); }
.project-thumbnail.ml { background: linear-gradient(135deg, #d69e2e 0%, #744210 100%); }

.project-card .project-card-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.project-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
  border-color: var(--accent);
}

.project-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
  line-height: 1.35;
}

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

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

.project-links a:not(.btn-github) {
  color: var(--accent);
  font-size: 0.9rem;
}

.project-card .project-course {
  font-size: 0.75rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.project-card p {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 14px;
  flex: 1;
  line-height: 1.55;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 16px;
}

.project-tags span {
  display: inline-block;
  padding: 4px 10px;
  background: var(--bg-alt);
  color: var(--text-light);
  font-size: 0.75rem;
  border-radius: 20px;
  font-weight: 500;
}

.project-card .project-tags span {
  background: var(--border);
  color: var(--text-light);
}

.project-links {
  display: flex;
  gap: 12px;
  margin-top: auto;
}

.project-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  transition: all var(--transition);
}

.btn-github {
  background: var(--primary);
  color: #0d0d0d;
}

.btn-github:hover {
  background: var(--accent);
  color: #0d0d0d;
}

/* ── Publications ── */
.publications-list {
  padding-bottom: 64px;
}

.pub-item {
  padding: 24px 0;
  border-bottom: 1px solid var(--border);
}

.pub-item:last-child {
  border-bottom: none;
}

.pub-title {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 4px;
}

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

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

.pub-venue {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 8px;
}

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

/* ── CV Page ── */
.cv-section {
  padding-bottom: 64px;
}

.cv-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--accent);
  color: #fff;
  border-radius: 6px;
  font-weight: 500;
  margin-bottom: 40px;
  transition: all var(--transition);
}

.cv-download:hover {
  background: var(--accent-dark);
  color: #0d0d0d;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(110,181,224,0.3);
}

.cv-block {
  margin-bottom: 40px;
}

.cv-block h2 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 16px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
  display: inline-block;
}

.cv-entry {
  margin-bottom: 24px;
  padding-left: 16px;
  border-left: 3px solid var(--bg-alt);
}

.cv-entry:hover {
  border-left-color: var(--accent);
}

.cv-entry h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--primary);
}

.cv-entry .cv-subtitle {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 4px;
}

.cv-entry .cv-date {
  font-size: 0.8rem;
  color: var(--accent);
  font-weight: 500;
}

.cv-entry ul {
  margin-top: 8px;
  padding-left: 18px;
}

.cv-entry li {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 4px;
}

/* CV — General Information table */
.cv-general-table {
  width: 100%;
  max-width: 520px;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.cv-general-table tr {
  border-bottom: 1px solid var(--border);
}

.cv-general-table tr:last-child {
  border-bottom: none;
}

.cv-general-table td {
  padding: 10px 16px 10px 0;
  vertical-align: top;
  color: var(--text);
}

.cv-general-table td:first-child {
  width: 160px;
  color: var(--text-light);
  font-weight: 500;
}

.cv-general-table strong {
  color: var(--primary);
  font-weight: 600;
}

/* CV — Timeline layout */
.cv-timeline {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.cv-timeline-item {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 24px;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
}

.cv-timeline-item:last-child {
  border-bottom: none;
}

.cv-timeline-date {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
  flex-shrink: 0;
}

.cv-timeline-body h3 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 2px;
}

.cv-timeline-place {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 8px;
}

.cv-timeline-body ul {
  margin: 0;
  padding-left: 18px;
}

.cv-timeline-body li {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 4px;
  line-height: 1.5;
}

.cv-interests {
  font-size: 0.9rem;
  color: var(--text-light);
  margin: 0;
}

@media (max-width: 600px) {
  .cv-timeline-item {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .cv-timeline-date {
    margin-bottom: 4px;
  }
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.skill-category h4 {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 4px;
}

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

/* ── Footer ── */
footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  text-align: center;
}

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

/* ── Responsive ── */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: rgba(13,13,13,0.98);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 16px 24px;
    gap: 12px;
  }

  .nav-links.active {
    display: flex;
  }

  .hero-content {
    flex-direction: column-reverse;
    gap: 32px;
  }

  .hero-image {
    align-self: center;
  }

  .hero-text h1 {
    font-size: 1.6rem;
  }

  .news-item {
    flex-direction: column;
    gap: 4px;
  }

  .news-date {
    width: auto;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }
}