/* ============================================
   KAMALAKAR PETA - PORTFOLIO
   Dark Slate Professional Theme
   ============================================ */

/* --- CSS Variables --- */
:root {
  --slate-900: #0f172a;
  --slate-800: #1e293b;
  --slate-700: #334155;
  --slate-600: #475569;
  --slate-500: #64748b;
  --slate-400: #94a3b8;
  --slate-300: #cbd5e1;
  --slate-200: #e2e8f0;
  --slate-100: #f1f5f9;
  --accent-primary: #3b82f6;
  --accent-secondary: #8b5cf6;
  --accent-gradient: linear-gradient(135deg, #3b82f6, #8b5cf6);
  --accent-glow: 0 0 20px rgba(59, 130, 246, 0.3);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--slate-900);
  color: var(--slate-300);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: color var(--transition);
}

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

h1, h2, h3, h4, h5, h6 {
  color: var(--slate-100);
  font-weight: 700;
  line-height: 1.2;
}

img {
  max-width: 100%;
  height: auto;
}

/* --- Navigation --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(51, 65, 85, 0.5);
  transition: all var(--transition);
}

.navbar.scrolled {
  background: rgba(15, 23, 42, 0.95);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo .logo-text {
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-links a {
  color: var(--slate-400);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: color var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-gradient);
  transition: width var(--transition);
}

.nav-links a:hover {
  color: var(--slate-100);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.hamburger,
.hamburger::before,
.hamburger::after {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--slate-300);
  border-radius: 2px;
  transition: all var(--transition);
}

.hamburger {
  position: relative;
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
}

.hamburger::before { top: -7px; }
.hamburger::after { top: 7px; }

/* --- Sections Common --- */
.section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-header p {
  font-size: 1.1rem;
  color: var(--slate-400);
  max-width: 600px;
  margin: 0 auto;
}

/* --- Hero Section --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 8rem 2rem 4rem;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(ellipse at center, rgba(59, 130, 246, 0.08) 0%, transparent 60%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}

@keyframes heroGlow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(2%, -2%) scale(1.05); }
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-block;
  padding: 0.5rem 1.25rem;
  border: 1px solid var(--slate-700);
  border-radius: 50px;
  font-size: 0.85rem;
  color: var(--accent-primary);
  font-weight: 500;
  margin-bottom: 2rem;
  background: rgba(59, 130, 246, 0.05);
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

.hero h1 .highlight {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--slate-400);
  margin-bottom: 2.5rem;
  max-width: 650px;
  margin-left: auto;
  margin-right: auto;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent-gradient);
  color: white;
  box-shadow: var(--accent-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(59, 130, 246, 0.4);
  color: white;
}

.btn-outline {
  border: 1px solid var(--slate-600);
  color: var(--slate-300);
  background: transparent;
}

.btn-outline:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  transform: translateY(-2px);
}

/* --- Architectural Gallery --- */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 2rem;
}

.gallery-card {
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
  position: relative;
}

.gallery-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-primary);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3), var(--accent-glow);
}

.gallery-card-img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  border-bottom: 1px solid var(--slate-700);
}

.gallery-card-body {
  padding: 1.5rem;
}

.gallery-card-body h3 {
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
}

.gallery-card-body p {
  font-size: 0.9rem;
  color: var(--slate-400);
}

.gallery-card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.tag {
  padding: 0.25rem 0.75rem;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: 50px;
  font-size: 0.75rem;
  color: var(--accent-primary);
  font-weight: 500;
}

/* --- Professional Timeline --- */
.timeline {
  position: relative;
  padding: 2rem 0;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-primary), var(--accent-secondary));
  transform: translateX(-50%);
}

.timeline-item {
  display: flex;
  align-items: flex-start;
  margin-bottom: 3rem;
  position: relative;
}

.timeline-item:nth-child(odd) {
  flex-direction: row-reverse;
}

.timeline-item:nth-child(odd) .timeline-content {
  text-align: right;
  margin-right: 3rem;
  margin-left: 0;
}

.timeline-item:nth-child(even) .timeline-content {
  margin-left: 3rem;
}

.timeline-dot {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent-primary);
  border: 3px solid var(--slate-900);
  box-shadow: 0 0 0 3px var(--accent-primary);
  z-index: 2;
}

.timeline-content {
  width: calc(50% - 2rem);
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: all var(--transition);
}

.timeline-content:hover {
  border-color: var(--accent-primary);
  box-shadow: var(--accent-glow);
}

.timeline-date {
  font-size: 0.85rem;
  color: var(--accent-primary);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.timeline-content h3 {
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
}

.timeline-content h4 {
  font-size: 0.95rem;
  color: var(--slate-400);
  font-weight: 500;
  margin-bottom: 0.75rem;
}

.timeline-content p {
  font-size: 0.9rem;
  color: var(--slate-400);
}

/* --- Blog Section --- */
.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 2rem;
}

.blog-card {
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: all var(--transition);
}

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

.blog-card-meta {
  font-size: 0.8rem;
  color: var(--slate-500);
  margin-bottom: 0.75rem;
}

.blog-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
}

.blog-card h3 a {
  color: var(--slate-100);
}

.blog-card h3 a:hover {
  color: var(--accent-primary);
}

.blog-card p {
  font-size: 0.9rem;
  color: var(--slate-400);
}

/* --- YouTube Section --- */
.youtube-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 2rem;
}

.youtube-card {
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}

.youtube-card:hover {
  transform: translateY(-3px);
  border-color: #ff0000;
  box-shadow: 0 10px 30px rgba(255, 0, 0, 0.1);
}

.youtube-card iframe {
  width: 100%;
  aspect-ratio: 16 / 9;
  border: none;
}

.youtube-card-thumbnail {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--slate-700), var(--slate-800));
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  border-bottom: 1px solid var(--slate-700);
}

.youtube-card-thumbnail i {
  font-size: 3rem;
  color: #ff0000;
  transition: transform var(--transition);
}

.youtube-card:hover .youtube-card-thumbnail i {
  transform: scale(1.15);
}

.youtube-card-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  padding: 0.2rem 0.5rem;
  background: rgba(0, 0, 0, 0.8);
  border-radius: 4px;
  font-size: 0.7rem;
  color: var(--slate-200);
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.youtube-card-body {
  padding: 1.25rem;
}

.youtube-card-body h3 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.youtube-card-body p {
  font-size: 0.85rem;
  color: var(--slate-400);
}

.youtube-card-telugu {
  font-size: 0.9rem;
  color: var(--accent-primary);
  font-style: italic;
  margin-bottom: 0.6rem;
  opacity: 0.85;
}

.youtube-lang-badge {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  background: rgba(255, 0, 0, 0.1);
  border: 1px solid rgba(255, 0, 0, 0.3);
  border-radius: 50px;
  font-size: 0.7rem;
  color: #ff6b6b;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

/* --- Tech Stack --- */
.techstack-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.techstack-category {
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: all var(--transition);
}

.techstack-category:hover {
  border-color: var(--accent-primary);
}

.techstack-category h3 {
  font-size: 1rem;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.techstack-category h3 i {
  color: var(--accent-primary);
}

.tech-items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tech-item {
  padding: 0.35rem 0.85rem;
  background: var(--slate-700);
  border-radius: 50px;
  font-size: 0.8rem;
  color: var(--slate-300);
  font-weight: 500;
  transition: all var(--transition);
}

.tech-item:hover {
  background: rgba(59, 130, 246, 0.15);
  color: var(--accent-primary);
}

/* --- About Section --- */
.about-container {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
  align-items: start;
}

.about-image {
  position: relative;
}

.about-image-wrapper {
  border-radius: var(--radius);
  overflow: hidden;
  border: 2px solid var(--slate-700);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.about-image-wrapper img {
  width: 100%;
  display: block;
}

.about-text h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.about-text p {
  margin-bottom: 1rem;
  color: var(--slate-400);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
}

.stat-item {
  text-align: center;
  padding: 1.25rem;
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius-sm);
}

.stat-number {
  font-size: 2rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--slate-500);
  margin-top: 0.25rem;
}

/* --- Footer --- */
.site-footer {
  background: var(--slate-800);
  border-top: 1px solid var(--slate-700);
  padding: 3rem 2rem;
  text-align: center;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
}

.footer-brand .logo-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--slate-100);
}

.footer-brand p {
  color: var(--slate-500);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin: 1.5rem 0;
}

.footer-links a {
  color: var(--slate-400);
  font-size: 1.25rem;
  transition: color var(--transition);
}

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

.footer-copy {
  font-size: 0.8rem;
  color: var(--slate-600);
}

/* --- Animations --- */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* --- Responsive --- */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: rgba(15, 23, 42, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    padding: 2rem;
    gap: 1.5rem;
    transform: translateY(-100%);
    opacity: 0;
    transition: all var(--transition);
    pointer-events: none;
    border-bottom: 1px solid var(--slate-700);
  }

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

  .hero h1 {
    font-size: 2.2rem;
  }

  .timeline::before {
    left: 20px;
  }

  .timeline-item,
  .timeline-item:nth-child(odd) {
    flex-direction: column;
    padding-left: 50px;
  }

  .timeline-dot {
    left: 20px;
  }

  .timeline-content,
  .timeline-item:nth-child(odd) .timeline-content {
    width: 100%;
    margin: 0;
    text-align: left;
  }

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

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

  .gallery-grid,
  .blog-grid,
  .youtube-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 4rem 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .about-stats {
    grid-template-columns: 1fr;
  }

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

/* --- Post Content --- */
.post-content {
  max-width: 800px;
  margin: 6rem auto 4rem;
  padding: 0 2rem;
}

.post-header h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.post-header time {
  color: var(--slate-500);
  font-size: 0.9rem;
}

.post-content p {
  margin-bottom: 1.5rem;
}

.post-content code {
  font-family: var(--font-mono);
  background: var(--slate-800);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  font-size: 0.9em;
}

.post-content pre {
  background: var(--slate-800);
  border: 1px solid var(--slate-700);
  border-radius: var(--radius-sm);
  padding: 1.5rem;
  overflow-x: auto;
  margin-bottom: 1.5rem;
}

.post-content pre code {
  background: none;
  padding: 0;
}