/* ==========================================================================
   Modern Minimal Portfolio Theme System
   ========================================================================== */

/* Design Tokens & CSS Variables */
:root {
  /* Light Theme Palette (Default) */
  --bg: #f8fafc;
  --bg-subtle: #f1f5f9;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: #ffffff;
  --border: rgba(226, 232, 240, 0.8);
  --border-hover: rgba(148, 163, 184, 0.4);
  
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-subtle: #64748b;
  
  --primary: #0284c7;
  --primary-hover: #0369a1;
  --primary-light: rgba(2, 132, 199, 0.08);
  --accent-gradient: linear-gradient(135deg, #0284c7 0%, #6366f1 100%);
  --accent-glow: rgba(2, 132, 199, 0.25);
  
  --tag-bg: #e2e8f0;
  --tag-text: #1e293b;
  --code-bg: #1e293b;
  --code-text: #f8fafc;
  
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.05), 0 8px 10px -6px rgba(15, 23, 42, 0.03);
  --shadow-lg: 0 20px 35px -10px rgba(15, 23, 42, 0.08);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  --font-main: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

[data-theme="dark"] {
  /* Dark Theme Palette */
  --bg: #090d16;
  --bg-subtle: #0f172a;
  --bg-card: rgba(17, 24, 39, 0.75);
  --bg-card-hover: rgba(30, 41, 59, 0.8);
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.2);
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-subtle: #64748b;
  
  --primary: #38bdf8;
  --primary-hover: #7dd3fc;
  --primary-light: rgba(56, 189, 248, 0.12);
  --accent-gradient: linear-gradient(135deg, #38bdf8 0%, #818cf8 100%);
  --accent-glow: rgba(56, 189, 248, 0.3);
  
  --tag-bg: rgba(30, 41, 59, 0.9);
  --tag-text: #cbd5e1;
  --code-bg: #0b1120;
  --code-text: #f8fafc;
  
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 10px 30px -5px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 25px 45px -10px rgba(0, 0, 0, 0.6);
}

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

html {
  scroll-behavior: smooth;
  color-scheme: light dark;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.6;
  transition: background-color 0.3s ease, color 0.3s ease;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* Ambient Background Glow */
body::before {
  content: '';
  position: fixed;
  top: -20vh;
  left: 50%;
  transform: translateX(-50%);
  width: 90vw;
  height: 60vh;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  opacity: 0.4;
  pointer-events: none;
  z-index: 0;
  filter: blur(80px);
}

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

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

/* Layout Container */
.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.article-container {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.section {
  padding: 80px 0;
}

.section-header {
  margin-bottom: 40px;
}

.section-title {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-main);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
  margin-left: 12px;
}

.section-lead {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 600px;
}

/* Header & Navigation */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-card);
  backdrop-filter: blur(16px) saturate(180%);
  border-bottom: 1px solid var(--border);
  transition: var(--transition);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 8px;
}

.brand-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-gradient);
  border-radius: 50%;
  display: inline-block;
}

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

.nav-links a {
  color: var(--text-muted);
  font-size: 0.925rem;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-full);
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a[aria-current="true"] {
  color: var(--text-main);
  background-color: var(--primary-light);
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Theme Switcher Button */
.theme-toggle {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  color: var(--text-main);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
  outline: none;
}

.theme-toggle:hover {
  background: var(--primary-light);
  border-color: var(--primary);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  stroke-width: 2;
  transition: transform 0.4s ease;
}

.theme-toggle:hover svg {
  transform: rotate(15deg);
}

.icon-sun { display: none; }
.icon-moon { display: block; }

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

/* Mobile Menu Button */
.mobile-nav-toggle {
  display: none;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  color: var(--text-main);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

/* Hero Section */
.hero {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: center;
  padding-top: 60px;
  padding-bottom: 80px;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--primary-light);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 20px;
}

.status-dot {
  width: 8px;
  height: 8px;
  background-color: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 8px #10b981;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(1.2); }
  100% { opacity: 1; transform: scale(1); }
}

.hero-title {
  font-size: clamp(2.4rem, 5vw, 3.4rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.04em;
  margin-bottom: 20px;
}

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

.hero-bio {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 32px;
  max-width: 540px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: var(--transition);
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: var(--shadow-md), 0 4px 15px var(--accent-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg), 0 6px 20px var(--accent-glow);
  color: #ffffff;
}

.btn-secondary {
  background: var(--bg-card);
  border-color: var(--border);
  color: var(--text-main);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.btn-icon {
  width: 44px;
  height: 44px;
  padding: 0;
  border-radius: 50%;
}

/* Hero Avatar Container */
.avatar-container {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

.avatar-frame {
  position: relative;
  width: 240px;
  height: 240px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: var(--accent-gradient);
  padding: 4px;
  animation: morph 8s ease-in-out infinite;
  box-shadow: 0 15px 35px var(--accent-glow);
}

@keyframes morph {
  0% { border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%; }
  50% { border-radius: 60% 40% 30% 70% / 60% 30% 70% 40%; }
  100% { border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%; }
}

.avatar-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: inherit;
  background-color: var(--bg-subtle);
  filter: contrast(1.03);
}

/* Cards & Grid Layouts */
.grid {
  display: grid;
  gap: 24px;
}

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

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
}

/* Blog Cards */
.blog-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  height: 100%;
}

.blog-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.825rem;
  font-family: var(--font-mono);
  color: var(--text-subtle);
  margin-bottom: 12px;
}

.blog-category {
  color: var(--primary);
  background: var(--primary-light);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-weight: 600;
}

.blog-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
  line-height: 1.35;
  transition: var(--transition);
}

.blog-card:hover .blog-title {
  color: var(--primary);
}

.blog-excerpt {
  color: var(--text-muted);
  font-size: 0.925rem;
  margin-bottom: 20px;
  line-height: 1.55;
  flex-grow: 1;
}

.blog-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary);
}

.blog-link svg {
  transition: transform 0.2s ease;
}

.blog-card:hover .blog-link svg {
  transform: translateX(4px);
}

/* Single Blog Post Reading Styles */
.article-header {
  padding-top: 60px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 40px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.back-link:hover {
  color: var(--primary);
  transform: translateX(-3px);
}

.article-page-title {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
  color: var(--text-main);
}

.author-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 24px;
}

.author-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--primary);
}

.author-info {
  display: flex;
  flex-direction: column;
}

.author-name {
  font-weight: 700;
  color: var(--text-main);
  font-size: 0.975rem;
}

.article-body {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text-muted);
  margin-bottom: 60px;
}

.article-body p {
  margin-bottom: 24px;
}

.article-body h2 {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-main);
  margin-top: 48px;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.article-body h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-main);
  margin-top: 36px;
  margin-bottom: 12px;
}

.article-body ul, .article-body ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

.article-body li {
  margin-bottom: 8px;
}

.article-body blockquote {
  border-left: 4px solid var(--primary);
  padding: 16px 24px;
  background: var(--bg-subtle);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 32px 0;
  font-style: italic;
  color: var(--text-main);
}

.article-body code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--primary-light);
  color: var(--primary);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
}

.article-body pre {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 20px 24px;
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: 32px 0;
  border: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.6;
}

.article-body pre code {
  background: none;
  color: inherit;
  padding: 0;
}

.author-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  display: flex;
  align-items: center;
  gap: 24px;
  margin-bottom: 60px;
}

/* Skills Section */
.skill-category {
  margin-bottom: 24px;
}

.skill-category-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  margin-bottom: 12px;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tag {
  background: var(--tag-bg);
  color: var(--tag-text);
  font-size: 0.85rem;
  font-family: var(--font-mono);
  font-weight: 500;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border);
  transition: var(--transition);
}

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

/* Experience Timeline */
.timeline {
  position: relative;
  padding-left: 28px;
}

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

.timeline-item {
  position: relative;
  margin-bottom: 36px;
}

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

.timeline-dot {
  position: absolute;
  left: -28px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg);
  border: 3px solid var(--primary);
  transition: var(--transition);
}

.timeline-item:hover .timeline-dot {
  background: var(--primary);
  box-shadow: 0 0 10px var(--accent-glow);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 8px;
}

.timeline-role {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
}

.timeline-company {
  color: var(--primary);
  font-weight: 600;
}

.timeline-date {
  font-size: 0.85rem;
  font-family: var(--font-mono);
  color: var(--text-subtle);
  background: var(--bg-subtle);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

.timeline-desc {
  color: var(--text-muted);
  font-size: 0.975rem;
}

.timeline-desc p {
  margin-bottom: 6px;
}

/* Certifications */
.cert-card {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.cert-icon {
  width: 48px;
  height: 48px;
  background: var(--primary-light);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  flex-shrink: 0;
}

/* Contact Form */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 40px;
}

.contact-info-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-top: 24px;
}

.contact-info-item {
  display: flex;
  align-items: center;
  gap: 14px;
}

.contact-info-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-main);
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  font-family: var(--font-main);
  font-size: 0.95rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text-main);
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

textarea.form-control {
  min-height: 130px;
  resize: vertical;
}

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 40px 0;
  margin-top: 60px;
  color: var(--text-subtle);
  font-size: 0.9rem;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.social-links {
  display: flex;
  gap: 16px;
}

.social-links a {
  color: var(--text-subtle);
  font-size: 1.1rem;
  transition: var(--transition);
}

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

/* Responsive Media Queries */
@media (max-width: 868px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 36px;
    padding-top: 30px;
  }

  .status-badge {
    margin-inline: auto;
  }

  .hero-bio {
    margin-inline: auto;
  }

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

  .avatar-frame {
    width: 200px;
    height: 200px;
  }

  .grid-2, .grid-3, .contact-grid {
    grid-template-columns: 1fr;
  }

  .author-box {
    flex-direction: column;
    text-align: center;
  }

  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 20px;
    gap: 12px;
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    box-shadow: var(--shadow-lg);
  }

  .nav-links.active {
    transform: translateY(0);
  }

  .mobile-nav-toggle {
    display: flex;
  }
}