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

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  color: #1c1c1e;
  background: #ffffff;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #2563eb;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid #2563eb;
  outline-offset: 3px;
  border-radius: 2px;
}

ul {
  list-style: none;
}

/* =====================================================
   Layout
   ===================================================== */
.container {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
}

.section-alt {
  background: #f7f9fc;
}

/* =====================================================
   Nav
   ===================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #e5e7eb;
}

.nav {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 58px;
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-logo {
  font-weight: 700;
  font-size: 0.95rem;
  color: #1c1c1e;
  white-space: nowrap;
  flex-shrink: 0;
  letter-spacing: -0.01em;
}

.nav-logo:hover {
  text-decoration: none;
  color: #2563eb;
}

.nav-links {
  display: flex;
  gap: 0.25rem;
  align-items: center;
  margin-left: auto;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: #6b7280;
  padding: 0.4rem 0.75rem;
  border-radius: 6px;
  transition: color 0.15s, background 0.15s;
}

.nav-links a:hover {
  color: #2563eb;
  background: #eff6ff;
  text-decoration: none;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  margin-left: auto;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: #1c1c1e;
  border-radius: 2px;
  transition: transform 0.2s, opacity 0.2s;
}

/* =====================================================
   Hero / About
   ===================================================== */
.section-hero {
  padding-top: 6rem;
  padding-bottom: 6rem;
  background: linear-gradient(160deg, #f0f6ff 0%, #ffffff 55%);
  position: relative;
  overflow: hidden;
}

.section-hero::before {
  content: '';
  position: absolute;
  top: -80px;
  right: -80px;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(37,99,235,0.07) 0%, transparent 70%);
  pointer-events: none;
}

.hero-layout {
  display: flex;
  align-items: center;
  gap: 3.5rem;
}

.hero-content {
  flex: 1;
  min-width: 0;
}

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

.hero-image {
  width: 210px;
  height: 210px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center top;
  display: block;
  box-shadow: 0 0 0 4px #ffffff, 0 0 0 6px #dbeafe, 0 16px 40px rgba(37,99,235,0.15);
}

.hero-label {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: #2563eb;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
  background: #eff6ff;
  padding: 0.3rem 0.75rem;
  border-radius: 100px;
}

.hero-name {
  font-size: clamp(2.25rem, 6vw, 3.25rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.03em;
  color: #0f172a;
  margin-bottom: 0.5rem;
}

.hero-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: #64748b;
  margin-bottom: 1.5rem;
  letter-spacing: -0.01em;
}

.hero-tagline {
  font-size: 0.9875rem;
  color: #475569;
  max-width: 600px;
  margin-bottom: 2rem;
  line-height: 1.7;
}

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

/* =====================================================
   Buttons
   ===================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.6rem 1.35rem;
  background: #2563eb;
  color: #ffffff;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: 8px;
  transition: background 0.15s, box-shadow 0.15s, transform 0.1s;
  box-shadow: 0 1px 3px rgba(37,99,235,0.3), 0 4px 12px rgba(37,99,235,0.15);
}

.btn:hover {
  background: #1d4ed8;
  text-decoration: none;
  color: #ffffff;
  box-shadow: 0 2px 6px rgba(37,99,235,0.35), 0 6px 20px rgba(37,99,235,0.2);
  transform: translateY(-1px);
}

.btn-outline {
  background: #ffffff;
  color: #374151;
  border: 1.5px solid #d1d5db;
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.btn-outline:hover {
  background: #f9fafb;
  border-color: #9ca3af;
  text-decoration: none;
  color: #1c1c1e;
  transform: translateY(-1px);
  box-shadow: 0 2px 6px rgba(0,0,0,0.1);
}

/* =====================================================
   Section Title
   ===================================================== */
.section-title {
  font-size: 1.375rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 2.5rem;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.section-title::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 1.375rem;
  background: #2563eb;
  border-radius: 2px;
  flex-shrink: 0;
}

/* =====================================================
   Experience
   ===================================================== */
.exp-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.exp-card {
  padding: 1.75rem 1.75rem 1.75rem 1.5rem;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-left: 3px solid #2563eb;
  border-radius: 10px;
  transition: box-shadow 0.2s, transform 0.2s;
}

.exp-card:hover {
  box-shadow: 0 4px 16px rgba(0,0,0,0.07);
  transform: translateY(-2px);
}

.exp-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  margin-bottom: 0.6rem;
}

.exp-period {
  font-size: 0.775rem;
  font-weight: 600;
  color: #2563eb;
  background: #eff6ff;
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
}

.exp-location {
  font-size: 0.775rem;
  font-weight: 500;
  color: #6b7280;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.exp-role {
  font-size: 1.0625rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 0.1rem;
  letter-spacing: -0.01em;
}

.exp-company {
  font-size: 0.875rem;
  font-weight: 500;
  color: #64748b;
  margin-bottom: 1rem;
}

.exp-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.exp-bullets li {
  font-size: 0.9rem;
  color: #475569;
  padding-left: 1.1rem;
  position: relative;
  line-height: 1.6;
}

.exp-bullets li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 5px;
  height: 5px;
  background: #93c5fd;
  border-radius: 50%;
}

/* =====================================================
   Skills
   ===================================================== */
.skills-grid {
  display: flex;
  flex-direction: column;
  gap: 2.25rem;
}

.skills-group {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.skills-group-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: #94a3b8;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

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

.skills-tags li {
  font-size: 0.8125rem;
  font-weight: 500;
  color: #334155;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  padding: 0.35rem 0.85rem;
  border-radius: 100px;
  transition: border-color 0.15s, background 0.15s, color 0.15s;
  cursor: default;
}

.skills-tags li:hover {
  border-color: #93c5fd;
  background: #eff6ff;
  color: #1d4ed8;
}

/* Per-group accent colors */
.skills-group:nth-child(1) .skills-tags li:hover {
  border-color: #93c5fd;
  background: #eff6ff;
  color: #1d4ed8;
}

.skills-group:nth-child(2) .skills-tags li:hover {
  border-color: #a5b4fc;
  background: #eef2ff;
  color: #4338ca;
}

.skills-group:nth-child(3) .skills-tags li:hover {
  border-color: #6ee7b7;
  background: #f0fdf4;
  color: #065f46;
}

/* =====================================================
   Education
   ===================================================== */
.edu-card {
  padding: 1.5rem 1.75rem;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.edu-degree {
  font-size: 1rem;
  font-weight: 700;
  color: #0f172a;
  letter-spacing: -0.01em;
}

.edu-school {
  font-size: 0.9rem;
  color: #475569;
}

.edu-period {
  font-size: 0.8rem;
  color: #94a3b8;
  font-weight: 600;
  margin-top: 0.1rem;
}

/* =====================================================
   Contact
   ===================================================== */
.contact-intro {
  font-size: 1rem;
  color: #64748b;
  margin-bottom: 2rem;
}

.contact-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-list li {
  display: flex;
  align-items: center;
}

.contact-list a,
.contact-location {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.9375rem;
  font-weight: 500;
  padding: 0.6rem 1rem;
  border-radius: 8px;
  border: 1px solid #e2e8f0;
  background: #ffffff;
  color: #374151;
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
}

.contact-list a {
  color: #2563eb;
}

.contact-list a:hover {
  text-decoration: none;
  border-color: #bfdbfe;
  background: #eff6ff;
  box-shadow: 0 2px 8px rgba(37,99,235,0.08);
}

.contact-location {
  color: #6b7280;
  cursor: default;
}

/* =====================================================
   Footer
   ===================================================== */
.site-footer {
  border-top: 1px solid #e5e7eb;
  padding: 2rem 0;
  background: #f7f9fc;
}

.site-footer p {
  font-size: 0.8125rem;
  color: #9ca3af;
  text-align: center;
}

/* =====================================================
   Nav Contact Buttons
   ===================================================== */
.nav-contacts {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-left: 0.75rem;
  opacity: 0;
  pointer-events: none;
  transform: translateX(6px);
  transition: opacity 0.25s, transform 0.25s;
}

.nav-contacts.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateX(0);
}

.floating-btn {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: transparent;
  color: #6b7280;
  border: 1px solid #e2e8f0;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.floating-btn:hover {
  text-decoration: none;
  background: #2563eb;
  color: #ffffff;
  border-color: #2563eb;
}

/* =====================================================
   Back to Top
   ===================================================== */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 200;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: #2563eb;
  color: #ffffff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(37,99,235,0.35);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 0.25s, transform 0.25s, background 0.15s;
}

.back-to-top.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.back-to-top:hover {
  background: #1d4ed8;
  box-shadow: 0 6px 20px rgba(37,99,235,0.45);
  transform: translateY(-2px);
}

/* =====================================================
   Responsive — Mobile
   ===================================================== */
@media (max-width: 640px) {
  .section {
    padding: 3.5rem 0;
  }

  .section-hero {
    padding-top: 3.5rem;
    padding-bottom: 3.5rem;
  }

  .nav-contacts {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 58px;
    left: 0;
    right: 0;
    background: #ffffff;
    border-bottom: 1px solid #e5e7eb;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    margin-left: 0;
    padding: 0.5rem 0;
  }

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

  .nav-links a {
    display: block;
    width: 100%;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    border-radius: 0;
  }

  .hero-layout {
    flex-direction: column-reverse;
    gap: 2rem;
  }

  .hero-image {
    width: 140px;
    height: 140px;
  }

  .exp-card {
    padding: 1.25rem 1.25rem 1.25rem 1rem;
  }

  .hero-links {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    text-align: center;
  }

  .contact-list a,
  .contact-location {
    width: 100%;
  }
}