:root {
  --bg-primary: #0a0e17;
  --bg-secondary: #111827;
  --bg-card: #151d2e;
  --bg-card-hover: #1a2438;
  --accent: #00d4ff;
  --accent-dim: #0099cc;
  --accent-glow: rgba(0, 212, 255, 0.15);
  --text-primary: #f0f4f8;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border: rgba(0, 212, 255, 0.12);
  --border-strong: rgba(0, 212, 255, 0.25);
  --gradient-hero: linear-gradient(135deg, #0a0e17 0%, #111827 50%, #0d1b2a 100%);
  --font-sans: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}

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

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

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

/* Background grid */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: 0;
  opacity: 0.4;
}

.bg-glow {
  position: fixed;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.bg-glow--top {
  top: -200px;
  right: -100px;
}

.bg-glow--bottom {
  bottom: -300px;
  left: -200px;
}

/* Layout */
.container {
  width: min(1140px, 92%);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--text-primary);
  transition: opacity var(--transition);
}

.logo:hover {
  color: var(--text-primary);
  opacity: 0.92;
}

.logo__brand {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  line-height: 1.2;
}

.logo__name {
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.logo__tagline {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  opacity: 0.9;
}

.logo__icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, #151d2e 0%, #0a1628 100%);
  border: 1.5px solid var(--accent);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 800;
  color: var(--accent);
  box-shadow: 0 0 16px rgba(0, 212, 255, 0.15);
  flex-shrink: 0;
  position: relative;
}

.logo__icon::before {
  content: '';
  position: absolute;
  inset: 5px;
  border: 1px dashed rgba(0, 212, 255, 0.25);
  border-radius: 8px;
  pointer-events: none;
}

.logo__img {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  object-fit: cover;
  border: 1px solid var(--border-strong);
  flex-shrink: 0;
}

.logo__img--svg {
  background: transparent;
  border: none;
  filter: drop-shadow(0 0 8px rgba(0, 212, 255, 0.2));
}

.nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

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

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

.nav__link:hover,
.nav__link--active {
  color: var(--text-primary);
}

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

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 0.5rem;
}

/* Hero */
.hero {
  padding: 5rem 0 4rem;
  background: var(--gradient-hero);
}

.hero__content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  background: var(--accent-glow);
  border: 1px solid var(--border-strong);
  border-radius: 100px;
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--accent);
  margin-bottom: 1.5rem;
}

.hero__badge-dot {
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero__title {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 1.25rem;
}

.hero__title span {
  background: linear-gradient(135deg, var(--accent), #7dd3fc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__desc {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 2rem;
  max-width: 520px;
}

.hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 2rem;
}

.tag {
  padding: 0.35rem 0.85rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 100px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  transition: all var(--transition);
}

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

.hero__actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
}

.btn--primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-dim));
  color: var(--bg-primary);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--accent-glow);
  color: var(--bg-primary);
}

.btn--outline {
  background: transparent;
  border: 1px solid var(--border-strong);
  color: var(--text-primary);
}

.btn--outline:hover {
  border-color: var(--accent);
  background: var(--accent-glow);
  color: var(--accent);
}

/* Network visual */
.hero__visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.network-graph {
  width: 100%;
  max-width: 420px;
  aspect-ratio: 1;
  position: relative;
}

.network-node {
  position: absolute;
  width: 56px;
  height: 56px;
  background: var(--bg-card);
  border: 2px solid var(--border-strong);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  animation: float 6s ease-in-out infinite;
  box-shadow: var(--shadow);
}

.network-node--center {
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 72px;
  height: 72px;
  background: linear-gradient(135deg, var(--bg-card), var(--bg-secondary));
  border-color: var(--accent);
  font-size: 1.8rem;
  animation: none;
  z-index: 2;
}

.network-node--1 { top: 8%; left: 50%; transform: translateX(-50%); animation-delay: 0s; }
.network-node--2 { top: 25%; right: 5%; animation-delay: 1s; }
.network-node--3 { bottom: 25%; right: 5%; animation-delay: 2s; }
.network-node--4 { bottom: 8%; left: 50%; transform: translateX(-50%); animation-delay: 3s; }
.network-node--5 { bottom: 25%; left: 5%; animation-delay: 4s; }
.network-node--6 { top: 25%; left: 5%; animation-delay: 5s; }

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.network-lines {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.network-lines line {
  stroke: var(--border-strong);
  stroke-width: 1.5;
  stroke-dasharray: 6 4;
  animation: dash 20s linear infinite;
}

@keyframes dash {
  to { stroke-dashoffset: -200; }
}

/* Sections */
.section {
  padding: 4rem 0;
}

.section__header {
  text-align: center;
  margin-bottom: 3rem;
}

.section__label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: 0.75rem;
}

.section__title {
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  font-weight: 700;
}

.section__desc {
  color: var(--text-secondary);
  margin-top: 0.75rem;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

/* Categories */
.categories {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
}

.category-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: all var(--transition);
  cursor: pointer;
}

.category-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.3);
}

.category-card__icon {
  width: 48px;
  height: 48px;
  background: var(--accent-glow);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.category-card__title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.category-card__desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.category-card__count {
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
}

/* Blog cards */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.post-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
}

.post-card:hover {
  border-color: var(--border-strong);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.post-card__image {
  height: 180px;
  background: linear-gradient(135deg, var(--bg-secondary), var(--bg-card));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  border-bottom: 1px solid var(--border);
}

.post-card__image--photo {
  padding: 0;
  overflow: hidden;
}

.post-card__image--photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.post-card__body {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.post-card__meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.post-card__category {
  color: var(--accent);
  background: var(--accent-glow);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
}

.post-card__title {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  line-height: 1.4;
}

.post-card__title a {
  color: var(--text-primary);
}

.post-card__title a:hover {
  color: var(--accent);
}

.post-card__excerpt {
  font-size: 0.9rem;
  color: var(--text-secondary);
  flex: 1;
  margin-bottom: 1rem;
}

.post-card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
}

.read-more {
  color: var(--accent);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.read-more:hover {
  gap: 0.6rem;
}

/* Stats */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  padding: 3rem 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.stat {
  text-align: center;
}

.stat__number {
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent), #7dd3fc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-family: var(--font-mono);
}

.stat__label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

/* About page */
.about-hero {
  padding: 4rem 0 3rem;
  text-align: center;
}

.about-avatar {
  width: 140px;
  height: 140px;
  margin: 0 auto 1.5rem;
  background: linear-gradient(135deg, var(--accent), var(--accent-dim));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--bg-primary);
  border: 4px solid var(--bg-card);
  box-shadow: 0 0 40px var(--accent-glow);
}

.about-avatar--img {
  display: block;
  object-fit: cover;
  background: var(--bg-card);
  padding: 6px;
}

.hero__photo {
  width: 100%;
  max-width: 420px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
}

.about-content {
  max-width: 720px;
  margin: 0 auto;
}

.about-content p {
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
  font-size: 1.05rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin-top: 2.5rem;
}

.skill-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  text-align: center;
}

.skill-item__icon {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.skill-item__name {
  font-weight: 600;
  font-size: 0.95rem;
}

/* Post detail */
.post-detail {
  max-width: 760px;
  margin: 0 auto;
  padding: 3rem 0 4rem;
}

.post-detail__back {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.post-detail__back:hover {
  color: var(--accent);
}

.post-detail__header {
  margin-bottom: 2.5rem;
}

.post-detail__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.post-detail__title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.post-detail__excerpt {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.post-detail__content {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.post-detail__content h2 {
  color: var(--text-primary);
  font-size: 1.5rem;
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.post-detail__content h3 {
  color: var(--text-primary);
  font-size: 1.2rem;
  margin: 2rem 0 0.75rem;
}

.post-detail__content p {
  margin-bottom: 1.25rem;
}

.post-detail__content ul,
.post-detail__content ol {
  margin: 1rem 0 1.25rem 1.5rem;
}

.post-detail__content li {
  margin-bottom: 0.5rem;
}

.post-detail__content code {
  font-family: var(--font-mono);
  background: var(--bg-card);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  font-size: 0.9em;
  color: var(--accent);
  border: 1px solid var(--border);
}

.post-detail__content pre {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  overflow-x: auto;
  margin: 1.5rem 0;
}

.post-detail__content pre code {
  background: none;
  border: none;
  padding: 0;
  color: var(--text-primary);
}

.post-detail__content blockquote {
  border-left: 3px solid var(--accent);
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
  background: var(--accent-glow);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--text-primary);
  font-style: italic;
}

.post-detail__footer {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.post-detail__footer p {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Breadcrumb */
.breadcrumb {
  padding: 1.5rem 0 0.5rem;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  list-style: none;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb__item:not(:last-child)::after {
  content: '›';
  margin-left: 0.35rem;
  color: var(--text-muted);
}

.breadcrumb__item a {
  color: var(--text-secondary);
}

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

.breadcrumb__item--current {
  color: var(--accent);
}
  border-left: 3px solid var(--accent);
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
  background: var(--accent-glow);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--text-primary);
  font-style: italic;
}

/* Contact */
.contact-section {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.contact-info__item {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
  color: var(--text-secondary);
}

.contact-info__icon {
  width: 44px;
  height: 44px;
  background: var(--accent-glow);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}

/* Footer */
.footer {
  padding: 3rem 0 2rem;
  border-top: 1px solid var(--border);
}

.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer__copy {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer__links {
  display: flex;
  gap: 1.5rem;
}

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

.footer__social {
  display: flex;
  gap: 0.75rem;
}

.social-link {
  width: 40px;
  height: 40px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: all var(--transition);
}

.social-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

/* Filter bar */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 2.5rem;
  justify-content: center;
}

.filter-btn {
  padding: 0.5rem 1.25rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 100px;
  color: var(--text-secondary);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-sans);
}

.filter-btn:hover,
.filter-btn--active {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

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

@keyframes fadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in:nth-child(2) { animation-delay: 0.1s; }
.fade-in:nth-child(3) { animation-delay: 0.2s; }
.fade-in:nth-child(4) { animation-delay: 0.3s; }
.fade-in:nth-child(5) { animation-delay: 0.4s; }
.fade-in:nth-child(6) { animation-delay: 0.5s; }

/* Responsive */
@media (max-width: 900px) {
  .hero__content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero__desc {
    margin-left: auto;
    margin-right: auto;
  }

  .hero__tags,
  .hero__actions {
    justify-content: center;
  }

  .hero__visual {
    order: -1;
  }

  .network-graph {
    max-width: 300px;
  }

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

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

@media (max-width: 768px) {
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    flex-direction: column;
    padding: 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
  }

  .nav--open {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

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