/* ===== RESET & VARIABLES ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg-0: #0f0b06;
  --bg-1: #16110a;
  --bg-2: #1c160d;
  --bg-card: #231a0f;
  --bg-card-hover: #2a2013;
  --border: rgba(255, 200, 100, 0.07);
  --border-active: rgba(245, 158, 11, 0.35);
  --accent: #f59e0b;
  --accent-glow: rgba(245, 158, 11, 0.12);
  --accent-2: #fb923c;
  --accent-3: #fcd34d;
  --accent-green: #34d399;
  --text-1: #fef3e2;
  --text-2: #a89070;
  --text-3: #5c4a30;
  --radius: 12px;
  --radius-sm: 6px;
  --radius-lg: 20px;
  --shadow: 0 4px 32px rgba(0, 0, 0, 0.6);
  --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.4);
  --transition: 0.2s ease;
  --max-width: 1140px;
  --nav-height: 64px;
  --section-pad: 80px;
}

html { scroll-behavior: smooth; }

body {
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  background: var(--bg-1);
  color: var(--text-1);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Prevent flex/grid children from overflowing their container */
* { min-width: 0; }
p, li, span { overflow-wrap: break-word; word-break: break-word; }

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; }
h1 { font-size: clamp(2.4rem, 6vw, 4.2rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.6rem, 3vw, 2.2rem); letter-spacing: -0.02em; }
h3 { font-size: 1.15rem; }
p { color: var(--text-2); }
a { color: var(--accent-2); text-decoration: none; transition: color var(--transition); }
a:hover { color: #fff; }
code, .mono { font-family: "Fira Code", "Cascadia Code", monospace; }

/* ===== UTILITIES ===== */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }
.section-label {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 0.75rem; font-weight: 600; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent);
  margin-bottom: 12px;
}
.section-label::before {
  content: ""; width: 28px; height: 2px; background: var(--accent); border-radius: 2px;
}
.section-title { margin-bottom: 48px; }
.tag {
  display: inline-flex; align-items: center;
  padding: 3px 10px; border-radius: 99px;
  font-size: 0.72rem; font-weight: 500; letter-spacing: 0.03em;
  background: rgba(245, 158, 11, 0.1); color: var(--accent);
  border: 1px solid rgba(245, 158, 11, 0.2);
  white-space: nowrap;
}
.tag.cyan   { background: rgba(251, 146, 60, 0.08); color: var(--accent-2); border-color: rgba(251, 146, 60, 0.2); }
.tag.green  { background: rgba(52, 211, 153, 0.08); color: var(--accent-green); border-color: rgba(52, 211, 153, 0.2); }
.tag.purple { background: rgba(252, 211, 77, 0.08); color: var(--accent-3); border-color: rgba(252, 211, 77, 0.2); }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 22px; border-radius: var(--radius-sm);
  font-size: 0.9rem; font-weight: 600; cursor: pointer;
  transition: all var(--transition); border: none;
  text-decoration: none;
}
.btn-primary {
  background: var(--accent); color: #000;
}
.btn-primary:hover { background: #e08d00; color: #000; transform: translateY(-1px); }
.btn-outline {
  background: transparent; color: var(--text-1);
  border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-1px); }

/* ===== SCROLL ANIMATIONS ===== */
.fade-in {
  opacity: 0; transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ===== NAV ===== */
#nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: var(--nav-height);
  background: rgba(22, 17, 10, 0.88);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}
.nav-container {
  max-width: var(--max-width); margin: 0 auto; padding: 0 24px;
  height: 100%; display: flex; align-items: center; justify-content: space-between;
}
.nav-logo {
  font-size: 1.1rem; font-weight: 800; letter-spacing: -0.02em;
  color: var(--text-1); text-decoration: none;
  background: linear-gradient(135deg, var(--accent-2), var(--accent));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.nav-links {
  display: flex; align-items: center; gap: 4px; list-style: none;
}
.nav-links a {
  padding: 6px 12px; border-radius: var(--radius-sm);
  font-size: 0.875rem; font-weight: 500; color: var(--text-2);
  transition: all var(--transition);
}
.nav-links a:hover, .nav-links a.active { color: var(--text-1); background: var(--bg-card); }
.nav-actions { display: flex; align-items: center; gap: 10px; }
.nav-toggle {
  display: none; background: none; border: 1px solid var(--border);
  color: var(--text-1); padding: 6px 10px; border-radius: var(--radius-sm);
  cursor: pointer; font-size: 1.1rem;
}

/* ===== HERO ===== */
#hero {
  min-height: 100vh; display: flex; align-items: center;
  padding-top: var(--nav-height);
  background: radial-gradient(ellipse 80% 50% at 50% -10%, rgba(245, 158, 11, 0.1), transparent),
              radial-gradient(ellipse 60% 40% at 80% 60%, rgba(251, 146, 60, 0.06), transparent);
}
.hero-content { max-width: 700px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border-radius: 99px;
  border: 1px solid rgba(245, 158, 11, 0.3);
  background: rgba(245, 158, 11, 0.08);
  font-size: 0.8rem; font-weight: 500; color: var(--accent-2);
  margin-bottom: 24px;
}
.hero-badge .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent-green); animation: pulse 2s infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.4; } }
.hero-name {
  font-size: clamp(2.8rem, 7vw, 5rem); font-weight: 800;
  letter-spacing: -0.04em; line-height: 1.05;
  background: linear-gradient(135deg, var(--text-1) 30%, var(--accent-2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
  margin-bottom: 8px;
}
.hero-title { font-size: clamp(1.1rem, 2.5vw, 1.4rem); color: var(--text-2); margin-bottom: 24px; font-weight: 400; }
.hero-tagline {
  display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px;
}
.hero-summary { font-size: 1rem; color: var(--text-2); max-width: 580px; margin-bottom: 36px; line-height: 1.75; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 48px; }
.hero-stats {
  display: flex; gap: 32px; flex-wrap: wrap;
  padding-top: 32px; border-top: 1px solid var(--border);
}
.hero-stat { text-align: center; }
.hero-stat-value { font-size: 1.8rem; font-weight: 800; color: var(--text-1); display: block; }
.hero-stat-label { font-size: 0.75rem; color: var(--text-3); text-transform: uppercase; letter-spacing: 0.08em; }
.hero-links { display: flex; gap: 12px; align-items: center; margin-top: 32px; }
.hero-link {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 14px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); color: var(--text-2);
  font-size: 0.85rem; font-weight: 500; transition: all var(--transition);
}
.hero-link:hover { border-color: var(--accent); color: var(--text-1); background: var(--accent-glow); }
.hero-link svg { width: 16px; height: 16px; }

/* ===== SECTION BASE ===== */
section { padding: var(--section-pad) 0; }
section:nth-child(even) { background: var(--bg-0); }

/* ===== EXPERIENCE ===== */
.timeline { position: relative; }
.timeline::before {
  content: ""; position: absolute; left: 20px; top: 0; bottom: 0;
  width: 2px; background: linear-gradient(to bottom, var(--accent), transparent);
}
.timeline-item {
  display: grid; grid-template-columns: 44px 1fr; gap: 20px; margin-bottom: 40px;
}
.timeline-dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--accent); border: 2px solid var(--bg-1);
  margin-top: 18px; z-index: 1; position: relative;
  box-shadow: 0 0 12px var(--accent);
}
.timeline-dot.current { background: var(--accent-green); box-shadow: 0 0 12px var(--accent-green); }
.timeline-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px;
  transition: border-color var(--transition), transform var(--transition);
}
.timeline-card:hover { border-color: var(--border-active); transform: translateX(4px); box-shadow: 0 0 20px rgba(0,255,136,0.06); }
.timeline-header { display: flex; flex-wrap: wrap; gap: 8px; align-items: flex-start; margin-bottom: 4px; }
.timeline-company { font-size: 1.05rem; font-weight: 700; color: var(--text-1); }
.timeline-role { font-size: 0.9rem; color: var(--accent-2); font-weight: 600; margin-bottom: 4px; }
.timeline-meta { display: flex; flex-wrap: wrap; gap: 12px; font-size: 0.8rem; color: var(--text-3); margin-bottom: 10px; }
.timeline-context { font-size: 0.8rem; color: var(--text-3); font-style: italic; margin-bottom: 14px; }
.timeline-desc { list-style: none; margin-bottom: 14px; }
.timeline-desc li {
  font-size: 0.88rem; color: var(--text-2); padding: 4px 0;
  padding-left: 16px; position: relative;
}
.timeline-desc li::before { content: "→"; position: absolute; left: 0; color: var(--accent); font-size: 0.75rem; top: 6px; }
.timeline-tech { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }

/* ===== PROJECTS ===== */
.project-filters {
  display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 32px;
}
.filter-btn {
  padding: 6px 16px; border-radius: 99px;
  border: 1px solid var(--border); background: transparent;
  color: var(--text-2); font-size: 0.82rem; font-weight: 500;
  cursor: pointer; transition: all var(--transition);
}
.filter-btn:hover, .filter-btn.active {
  border-color: var(--accent); color: var(--accent); background: var(--accent-glow);
}
.projects-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 24px;
}
.project-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px;
  display: flex; flex-direction: column; gap: 12px;
  transition: all var(--transition);
}
.project-card:hover { border-color: var(--border-active); transform: translateY(-4px); box-shadow: var(--shadow); }
.project-card.hidden { display: none; }
.project-img {
  width: calc(100% + 48px); margin: -24px -24px 16px;
  height: 180px; object-fit: cover; object-position: top;
  border-radius: var(--radius) var(--radius) 0 0;
  border-bottom: 1px solid var(--border);
  display: block;
  transition: opacity var(--transition);
}
.project-card:hover .project-img { opacity: 0.9; }
.project-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 8px; }
.project-name { font-size: 1.05rem; font-weight: 700; color: var(--text-1); }
.project-date { font-size: 0.75rem; color: var(--text-3); white-space: nowrap; }
.project-desc { font-size: 0.875rem; color: var(--text-2); line-height: 1.65; }
.project-desc li { list-style: none; padding: 2px 0; }
.project-desc li::before { content: "• "; color: var(--accent); }
.project-tech { display: flex; flex-wrap: wrap; gap: 5px; }
.project-links { display: flex; gap: 10px; margin-top: auto; padding-top: 4px; }
.project-link {
  display: inline-flex; align-items: center; gap: 5px;
  font-size: 0.8rem; color: var(--text-3);
  transition: color var(--transition);
}
.project-link:hover { color: var(--accent-2); }

/* ===== SKILLS ===== */
.skills-layout { display: grid; grid-template-columns: 1fr 380px; gap: 48px; align-items: start; }
.skill-categories { display: flex; flex-direction: column; gap: 24px; }
.skill-category-title {
  display: flex; align-items: center; gap: 8px;
  font-size: 0.95rem; font-weight: 600; color: var(--text-1);
  margin-bottom: 10px;
}
.skill-pills { display: flex; flex-wrap: wrap; gap: 7px; }
.skill-pill {
  padding: 5px 13px; border-radius: 99px;
  background: var(--bg-card); border: 1px solid var(--border);
  font-size: 0.8rem; color: var(--text-2); transition: all var(--transition);
}
.skill-pill:hover { border-color: var(--accent); color: var(--text-1); background: var(--accent-glow); }
.chart-container {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 28px; position: sticky; top: calc(var(--nav-height) + 24px);
}
.chart-title { font-size: 0.85rem; font-weight: 600; color: var(--text-2); margin-bottom: 20px; text-align: center; text-transform: uppercase; letter-spacing: 0.08em; }

/* ===== COURSES ===== */
.courses-filters { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 28px; }
.courses-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px;
}
.course-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 18px;
  transition: all var(--transition);
}
.course-card:hover { border-color: var(--border-active); }
.course-card.hidden { display: none; }
.course-title { font-size: 0.9rem; font-weight: 600; color: var(--text-1); margin-bottom: 6px; line-height: 1.4; }
.course-meta { display: flex; justify-content: space-between; align-items: center; margin-top: 10px; }
.course-platform { font-size: 0.75rem; color: var(--text-3); }
.course-date { font-size: 0.72rem; color: var(--text-3); }

/* ===== ACHIEVEMENTS ===== */
.achievements-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px;
}
.achievement-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 22px;
  display: flex; gap: 16px; align-items: flex-start;
  transition: all var(--transition);
}
.achievement-card:hover { border-color: var(--border-active); transform: translateY(-2px); }
.achievement-icon { font-size: 1.6rem; flex-shrink: 0; }
.achievement-title { font-size: 0.95rem; font-weight: 700; color: var(--text-1); margin-bottom: 2px; }
.achievement-meta { font-size: 0.75rem; color: var(--accent-2); margin-bottom: 6px; }
.achievement-desc { font-size: 0.82rem; color: var(--text-2); line-height: 1.6; }

/* ===== PUBLICATIONS & CONFERENCES ===== */
.publications-conferences { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.pub-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border: 1px solid rgba(232, 121, 249, 0.25);
  border-radius: var(--radius); padding: 24px;
  background: linear-gradient(135deg, var(--bg-card), rgba(232,121,249,0.05));
}
.pub-title { font-size: 1rem; font-weight: 700; color: var(--text-1); margin-bottom: 8px; line-height: 1.4; }
.pub-venue { font-size: 0.8rem; color: var(--accent); margin-bottom: 6px; }
.pub-desc { font-size: 0.85rem; color: var(--text-2); line-height: 1.65; margin-bottom: 12px; }
.pub-doi { font-size: 0.78rem; color: var(--text-3); font-family: monospace; }
.conf-list { display: flex; flex-direction: column; gap: 14px; }
.conf-item {
  display: flex; gap: 14px; align-items: flex-start;
  padding: 14px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: var(--bg-card);
  transition: all var(--transition);
}
.conf-item:hover { border-color: var(--border-active); }
.conf-role-badge {
  padding: 3px 8px; border-radius: 4px; font-size: 0.65rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em; flex-shrink: 0;
  background: rgba(16, 185, 129, 0.1); color: var(--accent-green);
  border: 1px solid rgba(16, 185, 129, 0.2);
}
.conf-role-badge.attendee { background: rgba(99,102,241,0.1); color: var(--accent); border-color: rgba(99,102,241,0.2); }
.conf-title { font-size: 0.9rem; font-weight: 600; color: var(--text-1); }
.conf-meta { font-size: 0.75rem; color: var(--text-3); margin-top: 2px; }

/* ===== CONTACT ===== */
#contact {
  text-align: center;
  background: radial-gradient(ellipse 60% 60% at 50% 100%, rgba(245, 158, 11, 0.08), transparent);
}
.contact-links { display: flex; justify-content: center; flex-wrap: wrap; gap: 14px; margin-top: 32px; }
.contact-link {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 24px; border-radius: var(--radius);
  border: 1px solid var(--border); background: var(--bg-card);
  color: var(--text-2); font-size: 0.9rem; font-weight: 500;
  transition: all var(--transition);
}
.contact-link:hover { border-color: var(--accent); color: var(--text-1); transform: translateY(-2px); box-shadow: var(--shadow-sm); }
.contact-link svg { width: 18px; height: 18px; }

/* ===== FOOTER ===== */
footer {
  padding: 28px 24px; text-align: center;
  border-top: 1px solid var(--border);
  font-size: 0.8rem; color: var(--text-3);
}

/* ===== MOBILE MENU ===== */
@media (max-width: 768px) {
  :root { --section-pad: 56px; }

  .nav-toggle { display: flex; }
  .nav-links {
    display: none; flex-direction: column; gap: 0;
    position: absolute; top: var(--nav-height); left: 0; right: 0;
    background: var(--bg-0); border-bottom: 1px solid var(--border);
    padding: 12px 0;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 10px 24px; border-radius: 0; }
  .nav-actions .btn { display: none; }

  .skills-layout { grid-template-columns: 1fr; }
  .chart-container { position: static; }
  .publications-conferences { grid-template-columns: 1fr; gap: 32px; }

  /* Stats: 2×2 grid so labels have room */
  .hero-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px 16px;
  }
  .hero-stat { text-align: left; }
  .hero-stat-label { white-space: normal; line-height: 1.3; }

  /* Links: wrap and truncate long email */
  .hero-links { flex-wrap: wrap; gap: 8px; }
  .hero-link { font-size: 0.78rem; padding: 6px 10px; }
  .hero-link.email-link {
    max-width: 100%; overflow: hidden;
    text-overflow: ellipsis; white-space: nowrap;
  }

  .timeline::before { left: 16px; }
  .timeline-item { grid-template-columns: 36px 1fr; gap: 14px; }
}

@media (max-width: 480px) {
  :root { --section-pad: 44px; }

  .hero-cta { flex-direction: column; }
  .btn { justify-content: center; }
  .hero-summary { font-size: 0.92rem; }

  /* Single column everywhere */
  .projects-grid, .achievements-grid, .courses-grid { grid-template-columns: 1fr; }

  /* Tighten contact links */
  .contact-links { gap: 8px; }
  .contact-link { padding: 10px 14px; font-size: 0.82rem; }
}


/* ===== LOADING SKELETON ===== */
.skeleton {
  background: linear-gradient(90deg, var(--bg-card) 25%, var(--bg-card-hover) 50%, var(--bg-card) 75%);
  background-size: 200% 100%; animation: shimmer 1.5s infinite; border-radius: 4px;
}
@keyframes shimmer { 0% { background-position: 200% 0; } 100% { background-position: -200% 0; } }