/* ===== DESIGN TOKENS ===== */
:root {
  --accent:      #60a5fa;
  --accent-dark: #3b82f6;
  --text:        #e2e8f0;
  --text-light:  #9ca3af;
  --border:      #3a3a3a;
  --bg:          #181818;
  --bg-alt:      #222222;
  --white:       #e2e8f0;
  --gray-light:  #3a3a3a;
  --transition:  0.15s ease;
  --radius:      6px;
  --radius-lg:   10px;
  --shadow-sm:   0 1px 3px rgba(0,0,0,.4);
  --shadow-md:   0 4px 12px rgba(0,0,0,.5);

  /* Legacy aliases so existing HTML classes keep working */
  --navy:        #222222;
  --navy-mid:    #2a2a2a;
  --navy-light:  #60a5fa;
  --amber:       #60a5fa;
  --amber-dark:  #3b82f6;
  --off-white:   #222222;
}

/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}
a { color: var(--accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-dark); text-decoration: underline; }
img { max-width: 100%; display: block; }

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5 {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  color: var(--text);
  line-height: 1.25;
  font-weight: 700;
}
h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h2 { font-size: clamp(1.3rem, 2.5vw, 1.75rem); }
h3 { font-size: 1.1rem; }
h4 { font-size: .95rem; font-weight: 600; }
p  { margin-bottom: 1rem; }

/* ===== LAYOUT ===== */
.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }
.section    { padding: 60px 0; }
.section-alt  { background: var(--bg-alt); }
.section-dark { background: var(--bg-alt); color: var(--text); }
.section-dark h2, .section-dark h3 { color: var(--text); }
.section-dark p, .section-dark li  { color: var(--text-light); }

.section-label {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--text-light);
  margin-bottom: .4rem;
  display: block;
}
.section-title { margin-bottom: 1rem; }
.section-title + p { color: var(--text-light); margin-bottom: 2rem; }

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-5 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }

/* ===== NAVIGATION ===== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  max-width: 960px;
  margin: 0 auto;
}
.nav-brand {
  font-size: .95rem;
  font-weight: 700;
  color: var(--text) !important;
  text-decoration: none !important;
}
.nav-links { display: flex; gap: 4px; align-items: center; }
.nav-links a {
  font-size: .85rem;
  color: var(--text-light) !important;
  padding: 5px 12px;
  border-radius: 5px;
  font-weight: 500;
  transition: color var(--transition);
  text-decoration: none !important;
}
.nav-links a:hover { color: var(--text) !important; }
.nav-links a.active { color: var(--accent) !important; font-weight: 600; }

/* ===== HERO ===== */
.hero {
  background: var(--bg);
  padding: 72px 0 60px;
  border-bottom: 1px solid var(--border);
}
.hero-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 48px;
  align-items: center;
}
.hero-text h1 { color: var(--text); margin-bottom: .4rem; }
.hero-subtitle {
  font-size: 1rem;
  color: var(--text-light);
  margin-bottom: .2rem;
}
.hero-subtitle-2 {
  font-size: .9rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 1.5rem;
}
.hero-quote {
  font-size: .9rem;
  color: var(--text-light);
  font-style: italic;
  margin-bottom: 1.75rem;
  border-left: 3px solid var(--border);
  padding-left: 14px;
}
.hero-quote span {
  display: block;
  font-size: .75rem;
  font-style: normal;
  margin-top: .25rem;
  color: var(--text-light);
}
.hero-buttons { display: flex; gap: 10px; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border-radius: 6px;
  font-size: .85rem;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
  text-decoration: none !important;
}
.btn-amber {
  background: var(--accent);
  color: white !important;
}
.btn-amber:hover {
  background: var(--accent-dark);
  color: white !important;
  text-decoration: none !important;
}
.btn-outline {
  background: transparent;
  color: var(--text) !important;
  border: 1.5px solid var(--border);
}
.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent) !important;
  text-decoration: none !important;
}
.btn-navy {
  background: var(--accent);
  color: var(--bg) !important;
}
.btn-navy:hover { background: var(--accent-dark); color: var(--bg) !important; }

.hero-photo {
  width: 180px;
  height: 180px;
  border-radius: 50%;
  border: 2px solid var(--border);
  background: var(--bg-alt);
  overflow: hidden;
  flex-shrink: 0;
}
.hero-photo img { width: 100%; height: 100%; object-fit: cover; }

/* ===== STATS BAR (kept for compat, hidden by default) ===== */
.stats-bar { display: none; }

/* ===== ABOUT ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 48px;
  align-items: start;
}
.about-bio p { color: var(--text-light); }
.about-bio p:last-of-type { margin-bottom: 0; }
.research-interests { margin-top: 1.5rem; }
.research-interests h4 {
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--text-light);
  margin-bottom: .6rem;
}
.tag-list { display: flex; flex-wrap: wrap; gap: 7px; }
.tag {
  font-size: .78rem;
  padding: 4px 11px;
  background: var(--bg-alt);
  border-radius: 20px;
  color: var(--text);
  font-weight: 500;
  border: 1px solid var(--border);
}
.contact-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
}
.contact-card h4 {
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--text-light);
  margin-bottom: .9rem;
}
.contact-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-bottom: .65rem;
  font-size: .875rem;
  color: var(--text-light);
}
.contact-item .icon { color: var(--text-light); margin-top: 2px; flex-shrink: 0; }
.contact-links { margin-top: 1rem; display: flex; flex-direction: column; gap: 7px; }
.contact-link-btn {
  font-size: .8rem;
  padding: 7px 14px;
  border-radius: 6px;
  text-align: center;
  font-weight: 600;
  transition: all var(--transition);
  display: block;
  text-decoration: none !important;
}
.contact-link-btn.scholar { background: #4285f4; color: white !important; }
.contact-link-btn.scholar:hover { background: #3367d6; }
.contact-link-btn.github  { background: #24292e; color: white !important; }
.contact-link-btn.github:hover  { background: #1a1e21; }

/* ===== RESEARCH THEMES ===== */
.theme-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition);
}
.theme-card:hover { border-color: var(--accent); }
.theme-number {
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--text-light);
  text-transform: uppercase;
  margin-bottom: .4rem;
}
.theme-card h3 { margin-bottom: .6rem; font-size: 1rem; }
.theme-card p  { font-size: .875rem; color: var(--text-light); flex: 1; margin-bottom: .75rem; }
.theme-papers {
  font-size: .75rem;
  color: var(--accent);
  border-top: 1px solid var(--border);
  padding-top: .65rem;
  margin-top: auto;
}

/* ===== HIGHLIGHTS (section-dark, now light) ===== */
.highlights-list { list-style: none; }
.highlight-year {
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 2rem 0 .75rem;
  padding-left: 24px;
  position: relative;
}
.highlight-year::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 16px;
  height: 2px;
  background: var(--accent);
}
.highlight-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}
.highlight-badge {
  font-size: .63rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: .04em;
  white-space: nowrap;
  flex-shrink: 0;
  margin-top: 3px;
}
.badge-conf    { background: #1e3a5f; color: #93c5fd; }
.badge-journal { background: #14532d; color: #86efac; }
.badge-grant   { background: #713f12; color: #fde68a; }
.badge-startup { background: #4c1d95; color: #d8b4fe; }
.badge-award   { background: #7f1d1d; color: #fca5a5; }
.badge-service { background: #0c4a6e; color: #7dd3fc; }
.highlight-text {
  font-size: .875rem;
  color: var(--text-light);
  line-height: 1.5;
}
.highlight-text strong { color: var(--text); }

/* ===== AWARDS ===== */
.award-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}
.award-card::before { display: none; }
.award-icon  { font-size: 1.5rem; margin-bottom: .5rem; }
.award-card h3 { font-size: .95rem; margin-bottom: .2rem; }
.award-card .award-org  { font-size: .8rem; color: var(--text-light); margin-bottom: .4rem; }
.award-card .award-year {
  font-size: .72rem;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .04em;
}

/* ===== ENTREPRENEURSHIP ===== */
.startup-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.startup-tag {
  display: inline-block;
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: .75rem;
}
.tag-active   { background: #14532d; color: #86efac; }
.tag-acquired { background: #1e3a5f; color: #93c5fd; }
.startup-name { font-size: 1.3rem; margin-bottom: .25rem; }
.startup-role { font-size: .85rem; color: var(--text-light); margin-bottom: 1rem; }
.startup-stats {
  display: flex;
  gap: 24px;
  margin: 1rem 0;
  padding: .75rem 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.startup-stat-val { font-size: 1.15rem; font-weight: 700; color: var(--text); }
.startup-stat-lbl { font-size: .72rem; color: var(--text-light); }
.startup-card p   { font-size: .875rem; color: var(--text-light); margin-bottom: 0; }

/* ===== PUBLICATIONS PAGE ===== */
.pub-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--border); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.pub-stat  { background: var(--bg); padding: 20px; text-align: center; }
.pub-stat .num { font-size: 1.75rem; font-weight: 700; color: var(--text); }
.pub-stat .lbl { font-size: .72rem; color: var(--text-light); text-transform: uppercase; letter-spacing: .08em; margin-top: 3px; }

.featured-paper {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 12px;
  background: var(--bg);
  display: grid;
  grid-template-columns: 28px 1fr;
  gap: 16px;
  align-items: start;
  transition: border-color var(--transition);
}
.featured-paper:hover { border-color: var(--accent); }
.paper-rank   { font-size: 1.4rem; font-weight: 900; color: var(--border); line-height: 1; margin-top: 2px; }
.paper-venue  { font-size: .7rem; font-weight: 700; letter-spacing: .07em; text-transform: uppercase; color: var(--accent); margin-bottom: .3rem; }
.paper-title  { font-size: .95rem; margin-bottom: .3rem; color: var(--text); }
.paper-authors { font-size: .78rem; color: var(--text-light); margin-bottom: .4rem; }
.paper-desc   { font-size: .85rem; color: var(--text-light); margin: 0; }

.pub-year-section { margin-bottom: 2.5rem; }
.pub-year-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 1rem;
  padding-bottom: .6rem;
  border-bottom: 2px solid var(--text);
}
.pub-year-title { font-size: 1.2rem; }
.pub-year-count {
  font-size: .72rem;
  background: var(--accent);
  color: var(--bg);
  padding: 2px 8px;
  border-radius: 20px;
}
.pub-list { list-style: none; }
.pub-item {
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 14px;
  align-items: start;
}
.pub-item:last-child { border-bottom: none; }
.pub-item-title   { font-size: .93rem; color: var(--text); margin-bottom: .15rem; font-weight: 600; }
.pub-item-authors { font-size: .78rem; color: var(--text-light); margin-bottom: .15rem; }
.pub-item-venue   { font-size: .78rem; font-style: italic; color: var(--text-light); }
.pub-item-venue strong { font-style: normal; color: var(--accent); }
.pub-badge {
  font-size: .63rem;
  font-weight: 700;
  padding: 3px 7px;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: .04em;
  white-space: nowrap;
  align-self: start;
}
.badge-j { background: #14532d; color: #86efac; }
.badge-c { background: #1e3a5f; color: #93c5fd; }

/* ===== STUDENTS PAGE ===== */
.student-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}
.student-card h3 { font-size: .95rem; margin-bottom: .2rem; }
.student-card .fellowship {
  font-size: .7rem;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .06em;
  margin-bottom: .4rem;
}
.student-card .area { font-size: .85rem; color: var(--text-light); margin-bottom: .6rem; }
.student-papers {
  font-size: .75rem;
  color: var(--text-light);
  border-top: 1px solid var(--border);
  padding-top: .5rem;
}
.placement-table { width: 100%; border-collapse: collapse; }
.placement-table th {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .07em;
  text-transform: uppercase;
  color: var(--text-light);
  padding: 9px 12px;
  text-align: left;
  border-bottom: 2px solid var(--border);
}
.placement-table td {
  font-size: .85rem;
  padding: 11px 12px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  vertical-align: top;
}
.placement-table tr:last-child td { border-bottom: none; }
.placement-table tr:hover td { background: var(--bg-alt); }

/* ===== PAGE HERO (inner pages) ===== */
.page-hero {
  background: var(--bg);
  padding: 40px 0 32px;
  border-bottom: 1px solid var(--border);
}
.page-hero h1 { color: var(--text); font-size: clamp(1.4rem, 2.5vw, 2rem); margin-bottom: .35rem; }
.page-hero p  { font-size: .9rem; color: var(--text-light); margin: 0; }
.page-hero .breadcrumb { font-size: .75rem; color: var(--text-light); margin-bottom: .6rem; }
.page-hero .breadcrumb a { color: var(--accent) !important; text-decoration: none !important; }

/* ===== PROJECTS PAGE ===== */
.role-badge {
  font-size: .62rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 3px;
  text-transform: uppercase;
  letter-spacing: .04em;
}
.role-pi  { background: #14532d; color: #86efac; }
.role-co  { background: #1e3a5f; color: #93c5fd; }

/* ===== FOOTER ===== */
footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  color: var(--text-light);
  padding: 32px 0;
}
.footer-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}
.footer-name { font-size: .9rem; font-weight: 600; color: var(--text); }
.footer-info { font-size: .8rem; margin-top: 3px; }
footer a { color: var(--accent) !important; text-decoration: none; }
footer a:hover { text-decoration: underline; }
.footer-links { display: flex; gap: 16px; }
.footer-links a { font-size: .8rem; color: var(--text-light) !important; }
.footer-links a:hover { color: var(--accent) !important; }

/* ===== UTILITIES ===== */
.divider { height: 1px; background: var(--border); }
.text-center { text-align: center; }
.mt-1 { margin-top: .5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-0 { margin-bottom: 0; }
.bold { font-weight: bold; }
.sans { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; }

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero-inner   { grid-template-columns: 1fr; }
  .hero-photo   { display: none; }
  .about-grid   { grid-template-columns: 1fr; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .pub-stats    { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { flex-direction: column; text-align: center; }
  .nav-links a  { padding: 5px 8px; font-size: .78rem; }
  .startup-stats { flex-wrap: wrap; gap: 14px; }
}
@media (max-width: 480px) {
  .section    { padding: 40px 0; }
  .pub-stats  { grid-template-columns: 1fr 1fr; }
  .pub-item   { grid-template-columns: 1fr; }
}