/* ============================================================
   Academic Portfolio – Refined CSS
   ============================================================ */

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

:root {
  --primary:       #0f172a;
  --primary-mid:   #1e293b;
  --accent:        #2563eb;
  --accent-dark:   #1d4ed8;
  --accent-light:  #dbeafe;
  --accent-subtle: #eff6ff;
  --text:          #1e293b;
  --text-light:    #64748b;
  --text-muted:    #94a3b8;
  --bg:            #ffffff;
  --bg-alt:        #f8fafc;
  --bg-card:       #ffffff;
  --border:        #e2e8f0;
  --border-light:  #f1f5f9;
  --radius:        8px;
  --radius-lg:     12px;
  --shadow-sm:     0 1px 2px rgba(0,0,0,.05);
  --shadow:        0 1px 3px rgba(0,0,0,.1), 0 1px 2px rgba(0,0,0,.06);
  --shadow-md:     0 4px 6px rgba(0,0,0,.07), 0 2px 4px rgba(0,0,0,.06);
  --shadow-lg:     0 10px 15px rgba(0,0,0,.1), 0 4px 6px rgba(0,0,0,.05);
  --max-w:         960px;
  --nav-h:         60px;
  --font:          'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono:          'SF Mono', 'Fira Code', 'Consolas', monospace;
}

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 24px); }

body {
  font-family: var(--font);
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--accent); text-decoration: none; transition: color .15s; }
a:hover { color: var(--accent-dark); }

img { max-width: 100%; display: block; }

/* ---------- Navigation ---------- */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: var(--nav-h);
  background: rgba(15, 23, 42, 0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex; align-items: center; justify-content: center;
  border-bottom: 1px solid rgba(255,255,255,.06);
  box-shadow: 0 4px 24px rgba(0,0,0,.2);
}

.navbar-inner {
  width: 100%; max-width: var(--max-w);
  padding: 0 28px;
  display: flex; align-items: center; justify-content: space-between;
}

.navbar .site-title {
  color: #fff;
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -.1px;
  transition: opacity .15s;
}
.navbar .site-title:hover { opacity: .8; color: #fff; }
.nav-credentials {
  font-weight: 400;
  font-size: 11.5px;
  opacity: .6;
  letter-spacing: .2px;
  margin-left: 3px;
}

.nav-links { display: flex; gap: 4px; list-style: none; }
.nav-links a {
  color: rgba(255,255,255,.65);
  font-size: 13.5px;
  font-weight: 500;
  padding: 6px 13px;
  border-radius: 6px;
  transition: background .15s, color .15s;
  letter-spacing: .1px;
}
.nav-links a:hover { color: #fff; background: rgba(255,255,255,.1); }
.nav-links a.active { color: #fff; background: rgba(37, 99, 235, .35); }

.hamburger {
  display: none; background: none; border: none; cursor: pointer;
  color: rgba(255,255,255,.85); font-size: 22px; padding: 4px;
}

/* ---------- Layout ---------- */
.main { margin-top: var(--nav-h); padding: 48px 24px 80px; }
.container { max-width: var(--max-w); margin: 0 auto; }

/* ---------- Profile Section ---------- */
.profile-section {
  display: flex; gap: 48px; align-items: flex-start;
  margin-bottom: 40px;
}

.profile-photo-wrapper { flex-shrink: 0; width: 200px; }

.profile-photo {
  width: 200px; height: 200px;
  object-fit: cover;
  border-radius: 50%;
  box-shadow: 0 0 0 4px #fff, 0 0 0 7px var(--accent), var(--shadow-lg);
}

.profile-meta {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.9;
  margin-top: 18px;
}
.profile-meta a { color: var(--accent); }

.profile-info { flex: 1; }

.profile-info h1 {
  font-size: 30px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--primary);
  letter-spacing: -.5px;
  line-height: 1.2;
}
.h1-credentials {
  font-weight: 400;
  font-size: 20px;
  color: var(--text-light);
}

.profile-info .subtitle {
  font-size: 14.5px;
  color: var(--text-light);
  margin-bottom: 0;
  line-height: 1.65;
}
.profile-info .subtitle a { color: var(--accent); font-weight: 500; }

/* ---------- Stats Row ---------- */
.stats-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin: 20px 0;
}
.stat-item {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 18px;
  min-width: 108px;
  text-align: center;
  transition: box-shadow .15s, border-color .15s;
}
.stat-item:hover {
  border-color: var(--accent-light);
  box-shadow: 0 2px 12px rgba(37,99,235,.1);
}
.stat-number {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.2;
  letter-spacing: -.5px;
}
.stat-label {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .7px;
  margin-top: 2px;
}

/* ---------- Social Links ---------- */
.social-links { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.social-links a {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 5px 13px; font-size: 12.5px; font-weight: 500;
  border: 1px solid var(--border); border-radius: 20px;
  color: var(--text-light);
  background: var(--bg);
  transition: border-color .15s, color .15s, background .15s, box-shadow .15s;
}
.social-links a:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-subtle);
  box-shadow: 0 2px 8px rgba(37,99,235,.12);
}

/* ---------- Research Interest Tags ---------- */
.research-interests { margin-top: 18px; }
.research-interests strong {
  font-size: 11px;
  color: var(--text-muted);
  display: block;
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: .8px;
  font-weight: 600;
}
.interest-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tag {
  background: var(--accent-subtle);
  color: var(--accent-dark);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 500;
  border: 1px solid var(--accent-light);
  transition: background .15s, box-shadow .15s;
}
.tag:hover {
  background: var(--accent-light);
  box-shadow: 0 2px 8px rgba(37,99,235,.15);
}

/* ---------- Bio Text ---------- */
.bio-text { line-height: 1.8; }
.bio-text p { margin-bottom: 16px; }

/* ---------- Section Block ---------- */
.section-block { margin: 2.5rem 0; }

/* ---------- Page Header ---------- */
.page-header { margin-bottom: 36px; }
.page-header h1 {
  font-size: 26px; font-weight: 700; color: var(--primary);
  display: inline-block;
  letter-spacing: -.3px;
}
.page-header .description { margin-top: 12px; color: var(--text-light); font-size: 15px; line-height: 1.7; }

/* ---------- Section Headings ---------- */
h2 {
  font-size: 18.5px; font-weight: 700; color: var(--primary);
  margin: 40px 0 18px;
  letter-spacing: -.2px;
}

h3 { font-size: 16px; font-weight: 600; margin: 22px 0 10px; color: var(--primary); }

/* ---------- Divider ---------- */
hr {
  display: none;
}

/* ---------- News ---------- */
.news-list { list-style: none; padding: 0; margin: 0; }
.news-list li {
  position: relative;
  padding: 10px 0 10px 20px;
  font-size: 14.5px;
  line-height: 1.75;
}
.news-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 18px;
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
}
.news-list li:last-child { border-bottom: none; }
.news-date {
  font-weight: 600;
  color: var(--accent);
  margin-right: 6px;
  font-size: 13px;
}

/* ---------- Publication List (publications.html) ---------- */
.pub-list { list-style: none; counter-reset: pub; padding: 0; }
.pub-list > li {
  position: relative; padding: 16px 0 16px 44px;
  line-height: 1.65;
}
.pub-list > li::before {
  counter-increment: pub;
  content: counter(pub) ".";
  position: absolute; left: 0; top: 16px;
  font-weight: 700; color: var(--text-muted); font-size: 13px; width: 32px; text-align: right;
}
.pub-list .pub-title { font-weight: 600; }
.pub-list .pub-venue { font-style: italic; color: var(--text-light); }

/* ---------- Selected Publications (index.html) ---------- */
.pub-legend {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 1.2rem;
  line-height: 2.2;
  padding: 12px 16px;
  background: var(--bg-alt);
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.pub-item {
  margin-bottom: 0;
  padding-top: 16px;
  padding-bottom: 16px;
  line-height: 1.6;
}
.pub-item .pub-title {
  font-weight: 600;
  font-size: 14.5px;
  margin-bottom: 4px;
  line-height: 1.5;
}
.pub-item .pub-title a { color: var(--primary); }
.pub-item .pub-title a:hover { color: var(--accent); text-decoration: underline; }
.pub-item .pub-authors {
  font-size: 13.5px;
  color: var(--text-light);
  margin-bottom: 3px;
}
.pub-item .pub-venue {
  font-size: 13px;
  color: var(--text-light);
  font-style: italic;
}
.pub-more {
  margin-top: 1.4rem;
  font-size: 14.5px;
  font-weight: 500;
}
.pub-more a { color: var(--accent); }
.pub-more a:hover { color: var(--accent-dark); }

/* ---------- Badges ---------- */
.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 20px;
  font-size: 10.5px;
  font-weight: 600;
  margin: 0 2px;
  text-decoration: none;
  vertical-align: middle;
  line-height: 1.8;
  white-space: nowrap;
  letter-spacing: .2px;
}
.badge-esi          { background: #fef9c3; color: #854d0e; border: 1px solid #fde68a; }
.badge-top100       { background: #dcfce7; color: #166534; border: 1px solid #bbf7d0; }
.badge-doi          { background: #e0e7ff; color: #3730a3; border: 1px solid #c7d2fe; }
.badge-arxiv        { background: #fce7f3; color: #9d174d; border: 1px solid #fbcfe8; }
.badge-highly-cited { background: #fef9c3; color: #854d0e; border: 1px solid #fde68a; }

/* ---------- Tables ---------- */
table { width: 100%; border-collapse: collapse; margin: 18px 0; font-size: 14.5px; }
th, td { text-align: left; padding: 11px 16px; }
th {
  font-weight: 600;
  background: var(--bg-alt);
  color: var(--primary);
  font-size: 11.5px;
  text-transform: uppercase;
  letter-spacing: .7px;
}
tr:last-child td { border-bottom: none; }

/* ---------- Lists ---------- */
.content-list { padding-left: 20px; margin: 10px 0; }
.content-list li { margin-bottom: 10px; line-height: 1.7; }

/* ---------- Cards ---------- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 16px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow .2s;
}
.card:hover { box-shadow: var(--shadow-md); }
.card h3 { margin-top: 0; }
.card .meta { font-size: 13px; color: var(--text-light); margin-bottom: 10px; font-weight: 500; }

/* ---------- Presentations ---------- */
.presentation-list { list-style: none; }
.presentation-list li { padding: 10px 0; }
.presentation-list .venue { font-weight: 600; }
.presentation-list .talk-title { font-style: italic; }

/* ---------- CV Page ---------- */
.cv-download {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 24px; background: var(--accent); color: #fff;
  border-radius: var(--radius-lg); font-weight: 600; font-size: 14px;
  transition: background .15s, box-shadow .15s;
  box-shadow: 0 4px 12px rgba(37,99,235,.3);
}
.cv-download:hover { background: var(--accent-dark); color: #fff; box-shadow: 0 6px 16px rgba(37,99,235,.4); }

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--border);
  padding: 28px 24px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  background: var(--bg-alt);
}

/* ---------- About Read More ---------- */
.bio-collapsed-extra[hidden] { display: none; }

.read-more-btn {
  margin-top: 8px;
  padding: 8px 18px;
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--bg);
  color: var(--accent);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  font-family: var(--font);
  transition: border-color .15s, color .15s, background .15s, box-shadow .15s;
}
.read-more-btn:hover {
  border-color: var(--accent);
  background: var(--accent-subtle);
  box-shadow: 0 2px 8px rgba(37,99,235,.15);
}

/* ---------- Topic / Callout Card ---------- */
.callout-card {
  border-left: 4px solid var(--accent);
  background: linear-gradient(135deg, #ffffff 0%, var(--accent-subtle) 100%);
  box-shadow: var(--shadow);
}
.callout-card h3 { margin-bottom: 8px; color: var(--accent-dark); }
.callout-card p:last-child { margin-bottom: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 700px) {
  .profile-section { flex-direction: column; align-items: center; text-align: center; }
  .profile-photo-wrapper { width: 100%; display: flex; flex-direction: column; align-items: center; }
  .profile-photo { width: 160px; height: 160px; margin: 0 auto; }
  .profile-meta { text-align: center; width: 100%; }
  .nav-credentials { font-size: 10px; }
  .navbar .site-title { font-size: 14px; }
  .social-links { justify-content: center; }
  .interest-tags { justify-content: center; }
  .stats-row { justify-content: center; }
  .hamburger { display: block; }
  .nav-links {
    display: none; flex-direction: column;
    position: absolute; top: var(--nav-h); right: 0;
    background: var(--primary); padding: 12px;
    border-radius: 0 0 var(--radius) var(--radius);
    box-shadow: var(--shadow-md);
    min-width: 160px;
  }
  .nav-links.open { display: flex; }
  .pub-list > li { padding-left: 34px; }
  table { font-size: 13px; }
  th, td { padding: 8px 10px; }
  .main { padding: 32px 16px 64px; }
  .stat-item { min-width: 90px; }
}