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

:root {
  --bg: #0a0a0f;
  --bg-card: #111118;
  --bg-elevated: #16161f;
  --border: #1e1e2a;
  --text: #e2e8f0;
  --text-muted: #7a7f96;
  --text-dim: #4a4e64;
  --accent: #6366f1;
  --accent-soft: rgba(99, 102, 241, 0.12);
  --accent-glow: rgba(99, 102, 241, 0.25);
  --cyan: #22d3ee;
  --radius: 10px;
  --radius-lg: 16px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1080px;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ── Navigation ── */
#nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1rem 0;
  transition: background var(--transition), box-shadow var(--transition), padding var(--transition);
}

#nav.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 var(--border);
  padding: 0.65rem 0;
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition);
  letter-spacing: -0.01em;
}

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

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

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-muted);
  border-radius: 2px;
  transition: var(--transition);
}

/* ── Sections ── */
section {
  padding: 6rem 0;
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 2.5rem;
}

/* ── Hero ── */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8rem 1.5rem 6rem;
  opacity: 1;
  transform: none;
}

.hero-content {
  max-width: 680px;
}

.hero-greeting {
  font-size: 1rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
}

.hero-name {
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.15;
  margin-bottom: 0.75rem;
  background: linear-gradient(135deg, var(--text) 0%, var(--text-muted) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-role {
  font-size: 1.15rem;
  color: var(--text-muted);
  font-weight: 400;
  margin-bottom: 1.5rem;
}

.hero-sep {
  color: var(--text-dim);
}

.hero-statement {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.75;
  margin-bottom: 2.5rem;
  max-width: 560px;
}

.hero-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition);
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: #5558e6;
  box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-outline {
  background: transparent;
  color: var(--text-muted);
  border-color: var(--border);
}

.btn-outline:hover {
  border-color: var(--text-dim);
  color: var(--text);
  background: var(--bg-card);
}

/* ── About ── */
#about {
  border-top: 1px solid var(--border);
}

.about-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 1rem;
  line-height: 1.8;
}

.about-text strong {
  color: var(--text);
  font-weight: 600;
}

.about-details {
  display: grid;
  gap: 1rem;
}

.detail-item {
  padding: 1rem 1.25rem;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
}

.detail-label {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  margin-bottom: 0.25rem;
  font-weight: 500;
}

.detail-value {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text);
}

/* ── Experience / Timeline ── */
#experience {
  border-top: 1px solid var(--border);
}

.timeline {
  position: relative;
  padding-left: 2.5rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: 2.5rem;
}

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

.timeline-marker {
  position: absolute;
  left: -2.5rem;
  top: 6px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 2px solid var(--accent);
  background: var(--bg);
}

.timeline-item:first-child .timeline-marker {
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.timeline-content {
  padding: 1.25rem 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}

.timeline-content:hover {
  border-color: var(--text-dim);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0.25rem;
}

.timeline-header h3 {
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.timeline-company {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
}

.timeline-date {
  display: block;
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 0.75rem;
}

.timeline-content p {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.timeline-content ul {
  padding-left: 1.1rem;
  list-style: disc;
}

.timeline-content li {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 0.3rem;
  line-height: 1.6;
}

.timeline-content li::marker {
  color: var(--text-dim);
}

/* ── Projects ── */
#projects {
  border-top: 1px solid var(--border);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.projects-loading {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 4rem 0;
  color: var(--text-muted);
}

.spinner {
  width: 28px;
  height: 28px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.project-card {
  display: flex;
  flex-direction: column;
  padding: 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  cursor: pointer;
}

.project-card:hover {
  border-color: var(--text-dim);
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.25);
}

.project-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
  color: var(--text-muted);
}

.project-card-header svg {
  color: var(--text-dim);
}

.project-lang {
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text-muted);
}

.lang-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

.project-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.project-card p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
  flex-grow: 1;
  margin-bottom: 1rem;
}

.project-meta {
  font-size: 0.75rem;
  color: var(--text-dim);
}

.error a {
  color: var(--accent);
  text-decoration: underline;
}

/* ── Skills ── */
#skills {
  border-top: 1px solid var(--border);
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.5rem;
}

.skill-category {
  padding: 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.skill-category h3 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  font-weight: 600;
  margin-bottom: 1rem;
}

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

.skill-tags span {
  padding: 0.35rem 0.75rem;
  border-radius: 6px;
  font-size: 0.825rem;
  font-weight: 500;
  color: var(--text-muted);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.skill-tags span:hover {
  color: var(--text);
  border-color: var(--text-dim);
  background: var(--bg);
}

/* ── Currently Learning ── */
#learning {
  border-top: 1px solid var(--border);
}

.learning-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.5rem;
}

.learning-card {
  padding: 1.75rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

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

.learning-icon {
  font-size: 1.5rem;
  display: block;
  margin-bottom: 0.75rem;
}

.learning-card h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.5rem;
}

.learning-card p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ── Contact ── */
#contact {
  border-top: 1px solid var(--border);
}

.contact-text {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 2rem;
  max-width: 520px;
}

.contact-links {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition);
}

.contact-card:hover {
  border-color: var(--text-dim);
  transform: translateY(-1px);
}

.contact-card svg {
  color: var(--accent);
  flex-shrink: 0;
}

.contact-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  display: block;
}

.contact-value {
  font-size: 0.9rem;
  color: var(--text);
  font-weight: 500;
}

/* ── Footer ── */
footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  text-align: center;
}

footer p {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* ── Responsive ── */
@media (max-width: 768px) {
  section {
    padding: 4rem 0;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .nav-links {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(10, 10, 15, 0.96);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2.5rem;
    z-index: 99;
  }

  .nav-links a {
    font-size: 1.25rem;
  }

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

  .nav-toggle {
    display: flex;
    z-index: 101;
  }

  body.nav-open .nav-toggle span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  body.nav-open .nav-toggle span:nth-child(2) {
    opacity: 0;
  }

  body.nav-open .nav-toggle span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  #hero {
    padding: 7rem 1.5rem 4rem;
    min-height: auto;
  }

  .hero-name {
    font-size: 2rem;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .timeline {
    padding-left: 2rem;
  }

  .timeline-marker {
    left: -2rem;
    width: 12px;
    height: 12px;
  }

  .timeline::before {
    left: 5px;
  }

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

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

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

  .contact-links {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 15px;
  }

  .hero-links {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}