/* Neural Pulse - Modern Professional Theme */

/* ========================================
   CSS Custom Properties (Design Tokens)
   ======================================== */
:root {
  /* Brand Colors - Modern Tech Theme */
  --primary: #3b82f6;
  --primary-dark: #2563eb;
  --primary-light: #60a5fa;
  --secondary: #8b5cf6;
  --accent: #f59e0b;
  --success: #10b981;
  --danger: #ef4444;

  /* Neutral Colors */
  --white: #ffffff;
  --gray-50: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --gray-400: #94a3b8;
  --gray-500: #64748b;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1e293b;
  --gray-900: #0f172a;
  --black: #020617;

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-serif: 'Merriweather', Georgia, serif;
  --font-mono: 'Fira Code', monospace;

  /* 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: 0.375rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 15px rgba(59, 130, 246, 0.5);

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Layout */
  --max-width: 1400px;
  --content-width: 850px;
  --sidebar-width: 380px;
}

/* Light Mode (Default) */
:root,
body.light-theme {
  --bg-primary: var(--white);
  --bg-secondary: var(--gray-50);
  --bg-tertiary: var(--gray-100);
  --text-primary: var(--gray-900);
  --text-secondary: var(--gray-600);
  --text-tertiary: var(--gray-500);
  --border-color: var(--gray-200);
  --header-bg: rgba(255, 255, 255, 0.85);
  --card-bg: var(--white);
  --overlay-bg: rgba(0, 0, 0, 0.5);
  --glass-border: rgba(255, 255, 255, 0.2);
}

/* Dark Mode */
body.dark-theme {
  --bg-primary: var(--gray-900);
  --bg-secondary: var(--gray-800);
  --bg-tertiary: var(--gray-700);
  --text-primary: var(--gray-50);
  --text-secondary: var(--gray-300);
  --text-tertiary: var(--gray-400);
  --border-color: var(--gray-700);
  --header-bg: rgba(15, 23, 42, 0.85);
  --card-bg: var(--gray-800);
  --overlay-bg: rgba(0, 0, 0, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
}

/* Auto Dark Mode (System Preference) */
@media (prefers-color-scheme: dark) {
  :root:not(.light-theme):not(.dark-theme) {
    --bg-primary: var(--gray-900);
    --bg-secondary: var(--gray-800);
    --bg-tertiary: var(--gray-700);
    --text-primary: var(--gray-50);
    --text-secondary: var(--gray-300);
    --text-tertiary: var(--gray-400);
    --border-color: var(--gray-700);
    --header-bg: rgba(15, 23, 42, 0.85);
    --card-bg: var(--gray-800);
    --overlay-bg: rgba(0, 0, 0, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
  }
}

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

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

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--transition-base), color var(--transition-base);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-md);
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: all var(--transition-fast);
  position: relative;
}

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

/* ========================================
   Typography
   ======================================== */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  letter-spacing: -0.02em;
}

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

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

h3 {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
}

h4 {
  font-size: 1.5rem;
}

p {
  margin-bottom: var(--spacing-md);
  color: var(--text-secondary);
}

.lead {
  font-size: 1.25rem;
  line-height: 1.8;
  color: var(--text-secondary);
  font-weight: 400;
}

/* ========================================
   Header & Navigation
   ======================================== */
.top-bar {
  background: var(--primary-dark);
  color: var(--white);
  padding: 0.5rem 0;
  font-size: 0.875rem;
}

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

.site-header {
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: all var(--transition-base);
}

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

.site-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.site-logo img {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
}

.main-nav ul {
  display: flex;
  gap: var(--spacing-sm);
  list-style: none;
  align-items: center;
}

.main-nav a {
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--primary);
  background: rgba(59, 130, 246, 0.1);
}

/* ========================================
   Featured Hero Section
   ======================================== */
.featured-hero {
  position: relative;
  height: 70vh;
  min-height: 600px;
  border-radius: 0 0 var(--radius-xl) var(--radius-xl);
  overflow: hidden;
  margin-bottom: var(--spacing-2xl);
  box-shadow: var(--shadow-lg);
}

.featured-hero-image {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.featured-hero:hover .featured-hero-image {
  transform: scale(1.02);
}

.featured-hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.4) 0%, rgba(15, 23, 42, 0.9) 100%);
}

.featured-hero-content {
  position: relative;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding-bottom: var(--spacing-3xl);
}

.featured-category {
  display: inline-block;
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(4px);
  color: var(--white);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.featured-hero h1 {
  color: var(--white);
  font-size: clamp(3rem, 7vw, 5rem);
  margin-bottom: var(--spacing-md);
  text-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
  max-width: 900px;
}

.featured-excerpt {
  color: var(--gray-300);
  font-size: 1.25rem;
  max-width: 700px;
  margin-bottom: var(--spacing-lg);
}

/* ========================================
   Main Content Layout
   ======================================== */
.main-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-lg);
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  gap: var(--spacing-3xl);
}

.sidebar {
  position: sticky;
  top: 100px;
  height: fit-content;
}

/* ========================================
   Post Cards
   ======================================== */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-2xl);
}

.post-card {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  border: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.post-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-light);
}

.post-card-image {
  position: relative;
  width: 100%;
  height: 240px;
  overflow: hidden;
}

.post-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 0;
}

.post-card:hover .post-card-image img {
  transform: scale(1.08);
}

.post-card-category {
  position: absolute;
  top: 1rem;
  left: 1rem;
  background: rgba(255, 255, 255, 0.9);
  color: var(--text-primary);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  box-shadow: var(--shadow-sm);
}

body.dark-theme .post-card-category {
  background: rgba(15, 23, 42, 0.9);
  color: var(--white);
}

.post-card-content {
  padding: var(--spacing-md);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.post-card h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-xs);
  line-height: 1.3;
}

.post-card h3 a {
  color: var(--text-primary);
}

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

.post-excerpt {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: var(--spacing-md);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-meta {
  margin-top: auto;
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  color: var(--text-tertiary);
}

/* ========================================
   Blog Listing (Professional List View)
   ======================================== */
.blog-listing {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
  max-width: 900px;
  margin: 0 auto;
}

.post-list-item {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
  border: 1px solid var(--border-color);
  display: block;
}

.post-list-item a {
  display: flex;
  flex-direction: row;
  color: inherit;
  text-decoration: none;
  height: 200px;
  /* Fixed height for consistency */
}

.post-list-item img {
  width: 300px;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
  transition: transform var(--transition-base);
}

.post-list-content {
  padding: var(--spacing-md) var(--spacing-lg);
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.post-list-item h2 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-xs);
  color: var(--text-primary);
  line-height: 1.3;
}

.post-list-item .post-excerpt {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-list-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary-light);
}

.post-list-item:hover img {
  transform: scale(1.05);
}

/* Responsive List View */
@media (max-width: 768px) {
  .post-list-item a {
    flex-direction: column;
    height: auto;
  }

  .post-list-item img {
    width: 100%;
    height: 200px;
  }

  .post-list-content {
    padding: var(--spacing-md);
  }

  .post-list-item h2 {
    font-size: 1.25rem;
  }
}

/* ========================================
   Sidebar Widgets
   ======================================== */
.widget {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.widget-title {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-xs);
  border-bottom: 2px solid var(--primary);
  display: inline-block;
}

.widget-list-item {
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--border-color);
}

.widget-list-item:last-child {
  border-bottom: none;
}

.widget-list-item a {
  font-weight: 500;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.widget-list-item a:hover {
  color: var(--primary);
  transform: translateX(4px);
}

/* ========================================
   Footer
   ======================================== */
.site-footer {
  background: var(--black);
  color: var(--gray-400);
  padding: var(--spacing-3xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-3xl);
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-3xl);
  margin-bottom: var(--spacing-3xl);
}

.footer-section h3 {
  color: var(--white);
  font-size: 1.25rem;
  margin-bottom: var(--spacing-lg);
}

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

.footer-section li {
  margin-bottom: 0.75rem;
}

.footer-section a {
  color: var(--gray-400);
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  border-top: 1px solid var(--gray-800);
  padding-top: var(--spacing-lg);
  text-align: center;
  font-size: 0.875rem;
}

/* ========================================
   Responsive Design
   ======================================== */
/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1024px) {
  .main-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
  }

  .sidebar {
    position: static;
    margin-top: var(--spacing-2xl);
  }

  .footer-container {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    gap: var(--spacing-md);
  }

  .featured-hero h1 {
    font-size: 2.5rem;
  }

  .footer-container {
    grid-template-columns: 1fr;
  }

  .main-nav ul {
    flex-wrap: wrap;
    justify-content: center;
  }
}

/* Forms & Buttons */
input,
textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-family: var(--font-sans);
  transition: all var(--transition-fast);
}

input:focus,
textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  background: var(--bg-primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
}

.btn-primary {
  background: var(--primary);
  color: var(--white);
}

.btn-primary:hover {
  background: var(--primary-dark);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* ========================================
   Utility Classes
   ======================================== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

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

.mt-lg {
  margin-top: var(--spacing-lg);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}