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

:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-text: #1e293b;
  --color-text-light: #64748b;
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafc;
  --color-border: #e2e8f0;
  --color-card: #ffffff;
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --max-width: 1100px;
  --nav-height: 64px;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
}

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

/* ========================================
   Layout
   ======================================== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 96px 0;
}

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

.section-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 48px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 48px;
  height: 3px;
  background: var(--color-primary);
  border-radius: 2px;
}

/* ========================================
   Navigation
   ======================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: box-shadow 0.3s ease;
}

.nav.scrolled {
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.08);
}

.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: 1.5rem;
  font-weight: 800;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-light);
  transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-primary);
}

.nav-blog-link {
  padding: 6px 16px;
  border: 1.5px solid var(--color-primary);
  border-radius: 6px;
  color: var(--color-primary) !important;
  transition: all 0.2s ease !important;
}

.nav-blog-link:hover {
  background: var(--color-primary);
  color: white !important;
}

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

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* ========================================
   Hero
   ======================================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--nav-height);
}

.hero-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}

.hero-content {
  max-width: 640px;
}

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

.hero-image img {
  width: 280px;
  height: 280px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center top;
  border: 4px solid var(--color-border);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

.hero-greeting {
  font-size: 1.1rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-bottom: 8px;
}

.hero-name {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}

.hero-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-text-light);
  margin-bottom: 20px;
}

.hero-tagline {
  font-size: 1.1rem;
  color: var(--color-text-light);
  line-height: 1.7;
  margin-bottom: 32px;
}

.hero-links {
  display: flex;
  gap: 16px;
  margin-bottom: 40px;
}

.hero-social {
  display: flex;
  gap: 20px;
}

.hero-social a {
  color: var(--color-text-light);
  transition: color 0.2s ease, transform 0.2s ease;
}

.hero-social a:hover {
  color: var(--color-primary);
  transform: translateY(-2px);
}

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  padding: 12px 28px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 8px;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
}

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

.btn-primary:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-outline {
  border: 1.5px solid var(--color-border);
  color: var(--color-text);
  background: transparent;
}

.btn-outline:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* ========================================
   About
   ======================================== */
.about-content {
  max-width: 720px;
}

.about-content p {
  font-size: 1.05rem;
  color: var(--color-text-light);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-content p:last-child {
  margin-bottom: 0;
}

/* ========================================
   Skills
   ======================================== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}

.skill-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 28px;
  transition: box-shadow 0.2s ease;
}

.skill-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.skill-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  display: inline-block;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 500;
  background: var(--color-bg-alt);
  color: var(--color-text-light);
  border-radius: 20px;
  border: 1px solid var(--color-border);
}

/* ========================================
   Experience Timeline
   ======================================== */
.timeline {
  position: relative;
  padding-left: 32px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--color-border);
}

.timeline-item {
  position: relative;
  margin-bottom: 48px;
}

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

.timeline-marker {
  position: absolute;
  left: -32px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 3px solid var(--color-primary);
  z-index: 1;
}

.timeline-item:first-child .timeline-marker {
  background: var(--color-primary);
}

.timeline-header {
  margin-bottom: 16px;
}

.timeline-header h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.timeline-company {
  display: block;
  font-size: 1rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-bottom: 4px;
}

.timeline-date {
  display: block;
  font-size: 0.85rem;
  color: var(--color-text-light);
  font-weight: 500;
}

.timeline-details {
  list-style: disc;
  padding-left: 20px;
}

.timeline-details li {
  font-size: 0.95rem;
  color: var(--color-text-light);
  line-height: 1.7;
  margin-bottom: 8px;
}

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

/* ========================================
   Projects
   ======================================== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.project-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 32px;
  transition: all 0.2s ease;
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.project-icon {
  color: var(--color-primary);
  margin-bottom: 20px;
}

.project-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.project-subtitle {
  font-size: 0.9rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-bottom: 12px;
}

.project-description {
  font-size: 0.9rem;
  color: var(--color-text-light);
  line-height: 1.7;
  margin-bottom: 16px;
}

.project-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 16px;
}

.project-stats span {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-primary);
  background: rgba(37, 99, 235, 0.08);
  padding: 4px 12px;
  border-radius: 20px;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.project-tags .tag {
  font-size: 0.75rem;
  padding: 3px 10px;
}

.project-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-primary);
  transition: gap 0.2s ease;
}

.project-link:hover {
  gap: 10px;
}

.project-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: #059669;
  background: rgba(5, 150, 105, 0.1);
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 12px;
}

.project-card-oss {
  border-color: rgba(5, 150, 105, 0.2);
}

.section-subtitle {
  color: var(--color-text-light);
  font-size: 1rem;
  margin-top: -36px;
  margin-bottom: 40px;
}

/* ========================================
   Impact Stats Bar
   ======================================== */
.stats-bar {
  padding: 48px 0;
  background: var(--color-text);
  color: #ffffff;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-number {
  display: block;
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  opacity: 0.7;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ========================================
   Technical Writing
   ======================================== */
.writing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.writing-card {
  display: block;
  padding: 24px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  transition: all 0.2s ease;
}

.writing-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  border-color: var(--color-primary);
}

.writing-date {
  font-size: 0.75rem;
  color: var(--color-text-light);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.writing-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 8px 0;
  line-height: 1.4;
  color: var(--color-text);
}

.writing-card p {
  font-size: 0.85rem;
  color: var(--color-text-light);
  line-height: 1.6;
  margin-bottom: 12px;
}

.writing-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.writing-tags .tag {
  font-size: 0.7rem;
  padding: 2px 8px;
}

/* ========================================
   Testimonials
   ======================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

.testimonial-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-primary);
  border-radius: 0 12px 12px 0;
  padding: 28px;
  position: relative;
}

.testimonial-quote {
  color: var(--color-primary);
  margin-bottom: 12px;
}

.testimonial-text {
  font-size: 0.95rem;
  color: var(--color-text-light);
  line-height: 1.7;
  font-style: italic;
  margin-bottom: 20px;
}

.testimonial-name {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text);
}

.testimonial-role {
  font-size: 0.8rem;
  color: var(--color-text-light);
}

/* ========================================
   Education
   ======================================== */
.education-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 32px;
  max-width: 480px;
}

.education-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.education-school {
  font-size: 1rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-bottom: 4px;
}

.education-location {
  font-size: 0.9rem;
  color: var(--color-text-light);
  margin-bottom: 4px;
}

.education-date {
  font-size: 0.85rem;
  color: var(--color-text-light);
  font-weight: 500;
}

/* ========================================
   Contact
   ======================================== */
.contact-intro {
  font-size: 1.05rem;
  color: var(--color-text-light);
  max-width: 560px;
  margin-bottom: 40px;
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  color: var(--color-text);
  transition: all 0.2s ease;
}

.contact-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

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

.contact-card span {
  font-size: 0.9rem;
  font-weight: 500;
}

/* ========================================
   Footer
   ======================================== */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer p {
  font-size: 0.85rem;
  color: var(--color-text-light);
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 768px) {
  .hero-inner {
    flex-direction: column-reverse;
    text-align: center;
    gap: 32px;
  }

  .hero-image img {
    width: 200px;
    height: 200px;
  }

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

  .hero-name {
    font-size: 2.5rem;
  }

  .hero-title {
    font-size: 1.25rem;
  }

  .section {
    padding: 64px 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-bg);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s ease;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .hero-links {
    flex-direction: column;
    gap: 12px;
  }

  .btn {
    text-align: center;
    justify-content: center;
  }

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

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

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

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .stat-number {
    font-size: 2rem;
  }

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

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

@media (max-width: 480px) {
  .hero-name {
    font-size: 2rem;
  }

  .container {
    padding: 0 16px;
  }
}

/* ========================================
   Animations
   ======================================== */
@media (prefers-reduced-motion: no-preference) {
  .fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
  }

  .fade-in.visible {
    opacity: 1;
    transform: translateY(0);
  }
}