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

:root {
  --bg:           #161b22;
  --bg-alt:       #1c2128;
  --surface:      #21262d;
  --border:       #30363d;
  --text:         #e6edf3;
  --text-muted:   #8b949e;
  --accent:       #64ffda;
  --accent-dim:   rgba(100, 255, 218, 0.12);
  --font-body:    'Inter', sans-serif;
  --font-heading: 'Space Grotesk', sans-serif;
  --nav-h:        64px;
  --max-w:        1100px;
  --ease:         0.3s ease;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* =====================================================
   TYPOGRAPHY
   ===================================================== */
h1, h2, h3, h4 {
  font-family: var(--font-heading);
  line-height: 1.2;
}

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

a:hover {
  opacity: 0.75;
}

/* =====================================================
   LAYOUT HELPERS
   ===================================================== */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
}

.section {
  padding: 6rem 0;
}

.section-alt {
  background-color: var(--bg-alt);
}

.section-title {
  font-size: clamp(1.5rem, 2.8vw, 2.1rem);
  color: var(--text);
  margin-bottom: 3rem;
  display: inline-block;
}

.section-title::after {
  content: '';
  display: block;
  width: 2.75rem;
  height: 3px;
  background: var(--accent);
  margin-top: 0.45rem;
  border-radius: 2px;
}

/* =====================================================
   SCROLL REVEAL
   ===================================================== */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* =====================================================
   NAVBAR
   ===================================================== */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 1000;
  background: rgba(28, 33, 40, 0.90);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--ease);
}

#navbar.scrolled {
  border-color: var(--border);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--accent);
  letter-spacing: 0.06em;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 1.75rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color var(--ease);
}

.nav-links a:hover {
  color: var(--text);
  opacity: 1;
}

.nav-cta {
  color: var(--accent) !important;
  border: 1px solid var(--accent);
  padding: 0.35rem 0.95rem;
  border-radius: 4px;
  transition: background var(--ease) !important;
}

.nav-cta:hover {
  background: var(--accent-dim);
  opacity: 1 !important;
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.4rem;
  cursor: pointer;
  padding: 0.25rem;
}

/* =====================================================
   HERO
   ===================================================== */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: calc(var(--nav-h) + 3rem) 2rem 5rem;
  background-color: var(--bg-alt);
}

.hero-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 4rem;
  width: 100%;
}

.hero-photo-wrap {
  flex-shrink: 0;
}

.hero-photo {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--accent);
  box-shadow: 0 0 40px rgba(100, 255, 218, 0.15);
}

.hero-text {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.hero-greeting {
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.hero-name {
  font-size: clamp(2.2rem, 4.5vw, 3.6rem);
  font-weight: 700;
  color: var(--text);
}

.hero-title {
  font-size: clamp(1rem, 2.2vw, 1.5rem);
  color: var(--text-muted);
  font-weight: 400;
}

.accent {
  color: var(--accent);
}

.hero-tagline {
  color: var(--text-muted);
  font-size: 1rem;
  max-width: 520px;
  margin-top: 0.2rem;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  margin-top: 0.75rem;
  flex-wrap: wrap;
}

/* =====================================================
   BUTTONS
   ===================================================== */
.btn {
  display: inline-block;
  padding: 0.6rem 1.5rem;
  border-radius: 4px;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--ease);
  text-decoration: none;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg);
}

.btn-primary:hover {
  background: rgba(100, 255, 218, 0.82);
  opacity: 1;
}

.btn-outline {
  border: 1px solid var(--accent);
  color: var(--accent);
  background: transparent;
}

.btn-outline:hover {
  background: var(--accent-dim);
  opacity: 1;
}

.btn-large {
  padding: 0.85rem 2.5rem;
  font-size: 1rem;
}

/* =====================================================
   ABOUT
   ===================================================== */
.about-text {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 800px;
  line-height: 1.85;
  border-left: 3px solid var(--accent);
  padding-left: 1.5rem;
}

/* =====================================================
   TIMELINE (EXPERIENCE)
   ===================================================== */
.timeline {
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

.timeline-group-label {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--accent);
  margin-bottom: 1.5rem;
}

.timeline-item {
  display: flex;
  gap: 1.25rem;
  padding-bottom: 2rem;
  position: relative;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item:not(:last-child)::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 18px;
  bottom: 0;
  width: 2px;
  background: var(--border);
}

.timeline-marker {
  flex-shrink: 0;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  margin-top: 0.45rem;
  box-shadow: 0 0 10px rgba(100, 255, 218, 0.4);
}

.timeline-content {
  flex: 1;
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0.2rem;
}

.timeline-role {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
}

.timeline-period {
  font-size: 0.78rem;
  color: var(--accent);
  white-space: nowrap;
  font-weight: 500;
  padding-top: 0.15rem;
}

.timeline-org {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 0.7rem;
}

.timeline-sub {
  opacity: 0.72;
}

.timeline-bullets {
  padding-left: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.timeline-bullets li {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* =====================================================
   LAST PROJECTS
   ===================================================== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  transition: transform var(--ease), border-color var(--ease), box-shadow var(--ease);
}

.project-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  box-shadow: 0 10px 32px rgba(100, 255, 218, 0.08);
}

.project-card-inner {
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  height: 100%;
}

.project-name {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text);
}

.project-org {
  font-size: 0.78rem;
  color: var(--accent);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.project-subtitle {
  font-size: 0.88rem;
  color: var(--text-muted);
  font-style: italic;
  margin-top: -0.15rem;
}

.project-link-disabled {
  margin-top: 0.75rem;
  font-size: 0.875rem;
  font-weight: 600;
  font-family: var(--font-heading);
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  opacity: 0.5;
  cursor: default;
}

.project-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
  flex: 1;
}

.project-link {
  margin-top: 0.75rem;
  font-size: 0.875rem;
  font-weight: 600;
  font-family: var(--font-heading);
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: gap var(--ease);
}

.project-link:hover {
  gap: 0.65rem;
  opacity: 1;
}

.arrow {
  display: inline-block;
  transition: transform var(--ease);
}

.project-link:hover .arrow {
  transform: translateX(4px);
}

/* =====================================================
   EDUCATION
   ===================================================== */
.edu-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.edu-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.75rem;
  transition: border-color var(--ease), transform var(--ease);
}

.edu-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
}

.edu-degree {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.3rem;
}

.edu-institution {
  font-size: 0.92rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 0.85rem;
}

.edu-meta {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.edu-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.edu-detail {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.edu-location {
  font-size: 0.8rem;
  color: var(--text-muted);
  opacity: 0.65;
}

/* =====================================================
   SKILLS
   ===================================================== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: 2rem;
}

.skill-group-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.13em;
  color: var(--text-muted);
  margin-bottom: 0.8rem;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.skill-tag {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.78rem;
  padding: 0.3rem 0.75rem;
  border-radius: 20px;
  transition: border-color var(--ease), color var(--ease);
}

.skill-tag:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* =====================================================
   HONORS
   ===================================================== */
.honors-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.honor-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 3px solid var(--accent);
  border-radius: 6px;
  padding: 1.5rem 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  transition: transform var(--ease), box-shadow var(--ease);
}

.honor-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(100, 255, 218, 0.07);
}

.honor-issuer {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
}

.honor-name {
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--text);
  font-family: var(--font-heading);
  line-height: 1.4;
  flex: 1;
}

.honor-year {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.4rem;
}

/* =====================================================
   CONTACT
   ===================================================== */
.contact-container {
  text-align: center;
}

.contact-text {
  color: var(--text-muted);
  font-size: 1rem;
  max-width: 460px;
  margin: 0 auto 2.25rem;
  line-height: 1.75;
}

/* =====================================================
   FOOTER
   ===================================================== */
footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 1.75rem 0;
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* =====================================================
   RESPONSIVE — TABLET
   ===================================================== */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    flex-direction: column;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--bg-alt);
    padding: 1.5rem 2rem;
    gap: 1.25rem;
    border-bottom: 1px solid var(--border);
  }

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

  .hamburger {
    display: block;
  }

  #hero {
    padding-top: calc(var(--nav-h) + 2rem);
  }

  .hero-inner {
    flex-direction: column;
    text-align: center;
    gap: 2rem;
  }

  .hero-tagline {
    max-width: 100%;
  }

  .hero-actions {
    justify-content: center;
  }

  .timeline-header {
    flex-direction: column;
    gap: 0.15rem;
  }

  .section {
    padding: 4rem 0;
  }
}

/* =====================================================
   RESPONSIVE — MOBILE
   ===================================================== */
@media (max-width: 480px) {
  .hero-photo {
    width: 160px;
    height: 160px;
  }

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