/* =========================================
   CSS Custom Properties — Dark & Light Themes
   GitHub-inspired palette
   ========================================= */

:root,
[data-theme="dark"] {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-tertiary: #1c2128;
  --bg-card: #161b22;
  --bg-card-hover: #1c2128;
  --bg-nav: rgba(13, 17, 23, 0.85);
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  --accent-blue: #58a6ff;
  --accent-green: #3fb950;
  --accent-purple: #bc8cff;
  --accent-glow: rgba(88, 166, 255, 0.15);
  --border-color: #30363d;
  --border-hover: #484f58;
  --code-bg: #161b22;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
}

[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f6f8fa;
  --bg-tertiary: #eaeef2;
  --bg-card: #ffffff;
  --bg-card-hover: #f6f8fa;
  --bg-nav: rgba(255, 255, 255, 0.85);
  --text-primary: #1f2328;
  --text-secondary: #656d76;
  --text-muted: #8b949e;
  --accent-blue: #0969da;
  --accent-green: #1a7f37;
  --accent-purple: #8250df;
  --accent-glow: rgba(9, 105, 218, 0.1);
  --border-color: #d0d7de;
  --border-hover: #afb8c1;
  --code-bg: #f6f8fa;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
}

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

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-green);
}

::selection {
  background: var(--accent-blue);
  color: var(--bg-primary);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

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

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--bg-nav);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav-logo:hover {
  color: var(--text-primary);
}

.logo-bracket {
  color: var(--accent-blue);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 8px;
}

.nav-link {
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: 8px;
  transition: color 0.2s ease, background-color 0.2s ease;
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-toggle {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-secondary);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  background: var(--accent-glow);
}

[data-theme="dark"] .icon-moon {
  display: none;
}

[data-theme="light"] .icon-sun {
  display: none;
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

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

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

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

.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 120px 24px 60px;
  position: relative;
}

.hero-content {
  max-width: 720px;
}

.hero-greeting {
  font-family: 'JetBrains Mono', monospace;
  font-size: 1rem;
  color: var(--accent-green);
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.hero-name {
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-blue) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-title {
  font-size: 1.15rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0;
}

.hero-title-static {
  color: var(--text-secondary);
}

.hero-title-separator {
  color: var(--text-muted);
}

.typing-wrapper {
  font-family: 'JetBrains Mono', monospace;
  color: var(--accent-blue);
}

.typing-cursor {
  animation: blink 1s step-end infinite;
  color: var(--accent-green);
  font-weight: 300;
}

@keyframes blink {
  50% { opacity: 0; }
}

.hero-summary {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 36px;
  max-width: 540px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.8;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-scroll-indicator {
  position: absolute;
  bottom: 32px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.75rem;
  letter-spacing: 2px;
  text-transform: uppercase;
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--accent-blue), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50% { opacity: 1; transform: scaleY(1); }
}

/* =========================================
   Buttons
   ========================================= */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.25s ease;
  border: 1px solid transparent;
}

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

.btn-primary:hover {
  background: transparent;
  color: var(--accent-blue);
  box-shadow: 0 0 20px var(--accent-glow);
}

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

.btn-outline:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  box-shadow: 0 0 20px var(--accent-glow);
}

/* =========================================
   Sections
   ========================================= */

.section {
  padding: 100px 0;
}

.section-alt {
  background: var(--bg-secondary);
  transition: background-color 0.3s ease;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 48px;
  padding-bottom: 12px;
  position: relative;
  display: inline-block;
}

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

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

.about-grid {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 48px;
  align-items: start;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-size: 0.95rem;
}

.code-hello {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85rem;
  background: var(--code-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 20px 24px;
  margin-bottom: 24px;
  line-height: 1.9;
  overflow-x: auto;
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.code-keyword { color: var(--accent-purple); }
.code-var { color: var(--accent-blue); }
.code-key { color: var(--text-primary); }
.code-string { color: var(--accent-green); }

.about-stats {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 24px;
  text-align: center;
  transition: all 0.3s ease;
}

.stat-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 24px var(--accent-glow);
  transform: translateY(-2px);
}

.stat-number {
  display: block;
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--accent-blue);
  font-family: 'JetBrains Mono', monospace;
}

.stat-label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

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

.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 28px 24px;
  transition: all 0.3s ease;
}

.skill-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 24px var(--accent-glow);
  transform: translateY(-4px);
}

.skill-icon {
  width: 48px;
  height: 48px;
  border-radius: 10px;
  background: var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--accent-blue);
}

.skill-category {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 12px;
}

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

.skill-tag {
  font-size: 0.8rem;
  font-family: 'JetBrains Mono', monospace;
  white-space: nowrap;
  padding: 4px 12px;
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  border-radius: 6px;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}

.skill-tag-secondary {
  opacity: 0.6;
  font-style: italic;
}

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

/* AI / Agentic Development Section */
.ai-section {
  margin-top: 40px;
  background: var(--bg-card);
  border: 1px solid var(--accent-blue);
  border-radius: 12px;
  padding: 28px 28px 24px;
  position: relative;
  overflow: hidden;
  transition: all 0.3s ease;
}

.ai-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-green), var(--accent-purple));
}

.ai-section:hover {
  box-shadow: 0 0 32px var(--accent-glow);
}

.ai-section-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.ai-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-blue);
  flex-shrink: 0;
}

.ai-section-header h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 0;
}

.ai-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  padding: 3px 10px;
  border-radius: 20px;
  background: rgba(63, 185, 80, 0.12);
  color: var(--accent-green);
  border: 1px solid rgba(63, 185, 80, 0.25);
}

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

.skill-tag-ai {
  border-color: var(--accent-blue) !important;
  color: var(--accent-blue) !important;
  background: var(--accent-glow) !important;
}

/* =========================================
   Timeline / Experience
   ========================================= */

.timeline {
  position: relative;
  padding-left: 40px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-blue), var(--accent-green), transparent);
}

.timeline-item {
  position: relative;
  margin-bottom: 40px;
}

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

.timeline-dot {
  position: absolute;
  left: -40px;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 3px solid var(--accent-blue);
  z-index: 2;
  transition: background-color 0.3s ease;
}

.timeline-dot::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent-glow);
  z-index: -1;
}

.timeline-content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 28px;
  transition: all 0.3s ease;
}

.timeline-content:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 24px var(--accent-glow);
}

.timeline-header h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.timeline-company {
  color: var(--accent-blue);
  font-weight: 600;
  font-size: 0.95rem;
}

.timeline-meta {
  display: flex;
  gap: 20px;
  margin: 12px 0 16px;
  flex-wrap: wrap;
}

.timeline-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.timeline-meta svg {
  color: var(--accent-blue);
}

.timeline-bullets {
  list-style: none;
  padding: 0;
}

.timeline-bullets li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 10px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
}

.timeline-bullets li::before {
  content: '\25b9';
  position: absolute;
  left: 0;
  color: var(--accent-green);
  font-size: 1rem;
}

.exp-subheading {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--accent-blue);
  margin: 20px 0 12px;
}

.exp-subheading:first-of-type {
  margin-top: 4px;
}

/* =========================================
   Education
   ========================================= */

.education-card {
  display: flex;
  gap: 24px;
  align-items: flex-start;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 32px;
  transition: all 0.3s ease;
}

.education-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 24px var(--accent-glow);
}

.education-icon {
  width: 56px;
  height: 56px;
  min-width: 56px;
  border-radius: 12px;
  background: var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-blue);
}

.education-info h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.education-college {
  color: var(--accent-blue);
  font-weight: 500;
  font-size: 0.95rem;
  margin-bottom: 12px;
}

.education-meta {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.education-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.education-meta svg {
  color: var(--accent-blue);
}

.education-cgpa {
  font-family: 'JetBrains Mono', monospace;
  color: var(--accent-green) !important;
  font-weight: 600;
}

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

.contact-intro {
  color: var(--text-secondary);
  font-size: 1.05rem;
  margin-bottom: 40px;
  max-width: 540px;
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.contact-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 32px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  transition: all 0.3s ease;
  color: var(--text-primary);
}

.contact-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 24px var(--accent-glow);
  transform: translateY(-4px);
  color: var(--text-primary);
}

.contact-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--accent-blue);
}

.contact-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

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

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

.footer {
  padding: 40px 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
  transition: border-color 0.3s ease;
}

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

.footer strong {
  color: var(--text-primary);
}

.footer-sub {
  color: var(--text-muted);
  font-size: 0.75rem;
  margin-top: 4px;
}

/* =========================================
   Scroll Reveal Animations
   ========================================= */

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Staggered delays for skill cards */
.skills-grid .skill-card:nth-child(1) { transition-delay: 0s; }
.skills-grid .skill-card:nth-child(2) { transition-delay: 0.1s; }
.skills-grid .skill-card:nth-child(3) { transition-delay: 0.2s; }
.skills-grid .skill-card:nth-child(4) { transition-delay: 0.3s; }
.skills-grid .skill-card:nth-child(5) { transition-delay: 0.4s; }
.skills-grid .skill-card:nth-child(6) { transition-delay: 0.5s; }

/* =========================================
   Responsive — Tablet
   ========================================= */

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    inset: 0;
    background: var(--bg-primary);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 16px;
    padding-top: 80px;
    padding-bottom: 40px;
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform 0.35s ease;
    z-index: 999;
  }

  .nav-links.open {
    transform: translateX(0);
  }

  .hamburger {
    display: flex;
    z-index: 1001;
  }

  .hero-name {
    font-size: clamp(2rem, 10vw, 3.5rem);
  }

  .hero-title {
    flex-direction: column;
    gap: 4px;
  }

  .hero-title-separator {
    display: none;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .about-stats {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .stat-card {
    flex: 1;
    min-width: 120px;
  }

  .skills-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-grid {
    grid-template-columns: 1fr;
    max-width: 400px;
  }

  .section {
    padding: 72px 0;
  }

  .timeline {
    padding-left: 32px;
  }

  .timeline-dot {
    left: -32px;
  }
}

/* =========================================
   Responsive — Mobile
   ========================================= */

@media (max-width: 480px) {
  .nav-container {
    padding: 0 16px;
  }

  .container {
    padding: 0 16px;
  }

  .hero {
    padding: 100px 16px 48px;
  }

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

  .about-stats {
    flex-direction: column;
  }

  .education-card {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .education-meta {
    justify-content: center;
  }

  .timeline-content {
    padding: 20px;
  }

  .timeline-meta {
    flex-direction: column;
    gap: 8px;
  }

  .ai-section {
    padding: 20px 16px 16px;
  }

  .ai-section-header {
    flex-wrap: wrap;
  }
}

/* =============================================
   Touch / Mobile: Always-on Glow
   Targets phones & tablets where hover doesn't
   exist — glow is shown permanently on scroll
   ============================================= */
@media (hover: none) and (pointer: coarse) {
  .skill-card {
    border-color: var(--accent-blue);
    box-shadow: 0 0 24px var(--accent-glow);
  }

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

  .stat-card {
    border-color: var(--accent-blue);
    box-shadow: 0 0 24px var(--accent-glow);
  }

  .ai-section {
    border-color: var(--accent-blue);
    box-shadow: 0 0 32px var(--accent-glow);
  }

  .timeline-content {
    border-color: var(--accent-blue);
    box-shadow: 0 0 24px var(--accent-glow);
  }

  .education-card {
    border-color: var(--accent-blue);
    box-shadow: 0 0 24px var(--accent-glow);
  }

  .contact-card {
    border-color: var(--accent-blue);
    box-shadow: 0 0 24px var(--accent-glow);
  }
}