/* ================================
   CSS Variables & Base Styles
   ================================ */

:root {
  /* Colors */
  --primary: #a855f7;
  --primary-dark: #9333ea;
  --primary-light: #c084fc;
  --secondary: #ec4899;
  --secondary-dark: #db2777;
  --accent: #3b82f6;
  
  --bg-primary: #faf7ff;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #f3f0ff;
  
  --text-primary: #1f1f1f;
  --text-secondary: #6b7280;
  --text-light: #9ca3af;
  
  --border-color: #e5e7eb;
  --border-light: rgba(168, 85, 247, 0.1);
  
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 20px 60px rgba(168, 85, 247, 0.12);
  --shadow-xl: 0 30px 80px rgba(168, 85, 247, 0.15);
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 6rem;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
  --transition-cubic: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ================================
   Reset & Base Styles
   ================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ================================
   Typography
   ================================ */

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
}

h2 {
  font-size: clamp(2rem, 4vw, 3rem);
}

h3 {
  font-size: clamp(1.5rem, 3vw, 2rem);
}

p {
  line-height: 1.7;
  color: var(--text-secondary);
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-base);
}

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

em {
  font-style: italic;
}

/* ================================
   Utility Classes
   ================================ */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.gradient-text {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ================================
   Scroll Progress Bar
   ================================ */

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  z-index: 9999;
  transition: width 0.1s ease;
}

/* ================================
   Navigation
   ================================ */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(250, 247, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  z-index: 1000;
  transition: var(--transition-base);
}

.navbar.scrolled {
  background: rgba(250, 247, 255, 0.95);
  box-shadow: var(--shadow-sm);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md) var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.logo-icon {
  font-size: 1.5rem;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-xl);
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  transition: var(--transition-base);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transition: width var(--transition-base);
}

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

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
}

.nav-toggle span {
  width: 25px;
  height: 3px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition-base);
}

/* ================================
   Hero Section
   ================================ */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding-top: 80px;
  overflow: hidden;
}

.hero-background {
  position: absolute;
  inset: 0;
  opacity: 0.4;
  pointer-events: none;
}

.hero-grid {
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(var(--border-light) 1px, transparent 1px),
    linear-gradient(90deg, var(--border-light) 1px, transparent 1px);
  background-size: 50px 50px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% { transform: translate(0, 0); }
  100% { transform: translate(50px, 50px); }
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 900px;
  animation: fadeInUp 1s ease;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-xs) var(--spacing-md);
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
}

.badge-icon {
  font-size: 1.2rem;
}

.hero-title {
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease 0.2s backwards;
}

.typing-container {
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  margin-bottom: var(--spacing-lg);
  animation: fadeInUp 1s ease 0.4s backwards;
}

.typing-text {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  font-weight: 600;
  color: var(--primary);
  min-width: 20ch;
  text-align: left;
}

.typing-cursor {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  font-weight: 300;
  color: var(--primary);
  animation: blink 1s infinite;
}

@keyframes blink {
  0%, 50% { opacity: 1; }
  51%, 100% { opacity: 0; }
}

.hero-description {
  font-size: clamp(1rem, 1.5vw, 1.125rem);
  max-width: 700px;
  margin: 0 auto var(--spacing-xl);
  animation: fadeInUp 1s ease 0.6s backwards;
}

.hero-cta {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--spacing-2xl);
  animation: fadeInUp 1s ease 0.8s backwards;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: 14px 32px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  border: none;
  transition: all var(--transition-cubic);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  box-shadow: 0 8px 20px rgba(168, 85, 247, 0.3);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 30px rgba(168, 85, 247, 0.4);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary);
  color: white;
  transform: translateY(-3px);
}

.hero-stats {
  display: flex;
  gap: var(--spacing-xl);
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 1s ease 1s backwards;
}

.stat-item {
  text-align: center;
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: var(--spacing-xs);
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.stat-divider {
  width: 1px;
  height: 50px;
  background: var(--border-color);
}

.scroll-indicator {
  position: absolute;
  bottom: var(--spacing-xl);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--text-light);
  font-size: 0.875rem;
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translate(-50%, 0); }
  50% { transform: translate(-50%, 10px); }
}

/* ================================
   Section Styles
   ================================ */

section {
  padding: var(--spacing-3xl) 0;
  position: relative;
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-badge {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-md);
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.section-title {
  margin-bottom: var(--spacing-md);
  position: relative;
  display: inline-block;
}

.section-description {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ================================
   About Section
   ================================ */

.about {
  background: var(--bg-secondary);
}

.about-content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
}

.about-card {
  background: var(--bg-card);
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-md);
  transition: var(--transition-cubic);
}

.about-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.main-card {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.05), rgba(236, 72, 153, 0.05));
  border: 2px solid var(--border-light);
}

.card-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
}

.about-card h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.about-card p {
  line-height: 1.8;
  margin-bottom: var(--spacing-md);
}

.about-card ul {
  list-style: none;
  padding: 0;
}

.about-card li {
  padding: var(--spacing-xs) 0;
  color: var(--text-secondary);
  line-height: 1.8;
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

/* ================================
   Projects Section
   ================================ */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--spacing-xl);
}

.project-card {
  background: var(--bg-card);
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-cubic);
  position: relative;
  overflow: hidden;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: scaleX(0);
  transition: transform var(--transition-cubic);
}

.project-card:hover::before {
  transform: scaleX(1);
}

.project-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary);
}

.project-card.featured {
  border: 2px solid var(--primary);
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.03), rgba(236, 72, 153, 0.03));
}

.project-card.highlight {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.05), rgba(168, 85, 247, 0.05));
  border: 2px solid rgba(59, 130, 246, 0.3);
}

.project-badge {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  padding: 4px 12px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.project-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
}

.project-title {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.project-description {
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: var(--spacing-lg);
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-lg);
}

.tag {
  padding: 4px 12px;
  background: var(--bg-hover);
  color: var(--primary);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
}

.project-stats {
  display: flex;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.stat {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.lang-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.lang-dot.c {
  background: #555555;
}

.lang-dot.cpp {
  background: #f34b7d;
}

.project-link {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--primary);
  font-weight: 600;
  transition: var(--transition-base);
}

.project-link:hover {
  gap: var(--spacing-sm);
}

/* ================================
   Skills Section
   ================================ */

.skills {
  background: var(--bg-secondary);
}

.skills-container {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3xl);
}

.skill-category {
  background: var(--bg-card);
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-md);
}

.category-title {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  font-size: 1.5rem;
  margin-bottom: var(--spacing-xl);
  color: var(--text-primary);
}

.category-icon {
  font-size: 2rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

.skill-card {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-lg);
  background: var(--bg-hover);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  transition: var(--transition-cubic);
}

.skill-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.skill-icon {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  min-width: 50px;
  text-align: center;
}

.skill-info {
  flex: 1;
}

.skill-name {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.skill-level {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.skill-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ================================
   Contact Section
   ================================ */

.contact-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--spacing-2xl);
  align-items: start;
}

.contact-info h3 {
  font-size: 1.75rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.contact-info > p {
  margin-bottom: var(--spacing-xl);
  line-height: 1.8;
}

.social-links {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-2xl);
}

.social-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-weight: 500;
  transition: var(--transition-cubic);
  box-shadow: var(--shadow-sm);
}

.social-link:hover {
  transform: translateX(8px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
  color: var(--primary);
}

.social-link svg {
  flex-shrink: 0;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.detail-item {
  display: flex;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  background: var(--bg-hover);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
}

.detail-icon {
  font-size: 1.5rem;
}

.detail-text {
  flex: 1;
}

.detail-label {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 4px;
}

.detail-value {
  font-weight: 600;
  color: var(--text-primary);
}

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

.cta-card {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.05), rgba(236, 72, 153, 0.05));
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  border: 2px solid var(--border-light);
  box-shadow: var(--shadow-md);
}

.cta-card h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.cta-card p {
  margin-bottom: var(--spacing-lg);
  line-height: 1.8;
}

/* ================================
   Footer
   ================================ */

.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--spacing-3xl) 0 var(--spacing-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-brand {
  max-width: 350px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
}

.footer-tagline {
  color: var(--text-secondary);
  line-height: 1.7;
}

.footer-column h4 {
  font-size: 1rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.footer-column ul {
  list-style: none;
}

.footer-column li {
  margin-bottom: var(--spacing-sm);
}

.footer-column a {
  color: var(--text-secondary);
  transition: var(--transition-base);
}

.footer-column a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--border-color);
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.footer-tech {
  margin-top: var(--spacing-xs);
  font-size: 0.75rem;
  opacity: 0.7;
}

/* ================================
   Back to Top Button
   ================================ */

.back-to-top {
  position: fixed;
  bottom: var(--spacing-xl);
  right: var(--spacing-xl);
  width: 50px;
  height: 50px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-cubic);
  box-shadow: var(--shadow-lg);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

/* ================================
   Animations
   ================================ */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  opacity: 0;
  transform: translateY(40px);
  transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* ================================
   Responsive Design
   ================================ */

@media (max-width: 1024px) {
  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
  
  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 768px) {
  :root {
    --spacing-3xl: 4rem;
  }
  
  .nav-menu {
    position: fixed;
    top: 73px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 73px);
    background: var(--bg-primary);
    flex-direction: column;
    gap: 0;
    padding: var(--spacing-lg);
    transition: left var(--transition-base);
    box-shadow: var(--shadow-lg);
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .nav-link {
    padding: var(--spacing-md) 0;
    font-size: 1.125rem;
    border-bottom: 1px solid var(--border-color);
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
  }
  
  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }
  
  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--spacing-lg);
  }
  
  .stat-divider {
    display: none;
  }
  
  .projects-grid,
  .about-grid,
  .skills-grid {
    grid-template-columns: 1fr;
  }
  
  .contact-content {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-brand {
    grid-column: 1;
  }
  
  .back-to-top {
    width: 45px;
    height: 45px;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
  }
}

@media (max-width: 480px) {
  .hero-cta {
    flex-direction: column;
    width: 100%;
  }
  
  .btn {
    width: 100%;
    justify-content: center;
  }
  
  .typing-text {
    text-align: center;
    min-width: auto;
  }
}