/* ========================================
   BLV Anh Ngọc Blog - Design System
   Premium Dark Theme with Modern Aesthetics
   ======================================== */

/* ===== CSS Custom Properties (Design Tokens) ===== */
:root {
  /* Color Palette */
  --color-primary: #ff6b35;
  --color-primary-light: #ff8c5a;
  --color-primary-dark: #e55a2b;
  --color-secondary: #ffd700;
  --color-secondary-light: #ffdf33;
  
  /* Background Colors */
  --bg-dark: #0a1628;
  --bg-card: #0f1d32;
  --bg-card-hover: #152540;
  --bg-glass: rgba(15, 29, 50, 0.7);
  --bg-gradient: linear-gradient(135deg, #0a1628 0%, #1a2d4a 50%, #0a1628 100%);
  --bg-hero-gradient: linear-gradient(180deg, rgba(10, 22, 40, 0.9) 0%, rgba(10, 22, 40, 0.95) 100%);
  
  /* Text Colors */
  --text-primary: #ffffff;
  --text-secondary: #a0aec0;
  --text-muted: #718096;
  --text-accent: var(--color-primary);
  
  /* Border Colors */
  --border-color: rgba(255, 255, 255, 0.1);
  --border-glow: rgba(255, 107, 53, 0.3);
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 30px rgba(255, 107, 53, 0.3);
  --shadow-gold: 0 0 20px rgba(255, 215, 0, 0.2);
  
  /* Typography */
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Roboto', -apple-system, BlinkMacSystemFont, sans-serif;
  
  /* Font Sizes */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  
  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;
  
  /* Container */
  --container-max: 1200px;
  --container-padding: var(--space-6);
}

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

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

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-dark);
  background-image: var(--bg-gradient);
  min-height: 100vh;
  overflow-x: hidden;
}

/* Background Pattern */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    radial-gradient(ellipse at 20% 20%, rgba(255, 107, 53, 0.05) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 80%, rgba(255, 215, 0, 0.03) 0%, transparent 50%);
  pointer-events: none;
  z-index: -1;
}

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

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

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

@media (max-width: 768px) {
  h1 { font-size: var(--text-4xl); }
  h2 { font-size: var(--text-2xl); }
  h3 { font-size: var(--text-lg); }
}

/* ===== Layout Components ===== */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section {
  padding: var(--space-20) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.section-title {
  margin-bottom: var(--space-4);
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: var(--color-primary);
  border-radius: var(--radius-full);
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: var(--text-lg);
  max-width: 600px;
  margin: 0 auto;
}

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-4) 0;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  transition: all var(--transition-base);
}

.navbar.scrolled {
  padding: var(--space-3) 0;
  background: rgba(10, 22, 40, 0.95);
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-xl);
  color: var(--text-primary);
}

.nav-logo-icon {
  width: 40px;
  height: 40px;
  background: var(--color-primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-lg);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition-fast);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition-fast);
}

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

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.lang-switch {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  background: var(--bg-card);
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
}

.lang-btn {
  padding: var(--space-1) var(--space-2);
  font-size: var(--text-sm);
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.lang-btn.active {
  background: var(--color-primary);
  color: var(--text-primary);
}

.lang-btn:hover:not(.active) {
  color: var(--text-primary);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
}

.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition-fast);
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  
  .mobile-menu-btn {
    display: flex;
  }
  
  .nav-menu.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-dark);
    padding: var(--space-6);
    gap: var(--space-4);
    border-bottom: 1px solid var(--border-color);
  }
}

/* ===== Hero Section ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-24) 0 var(--space-16);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-hero-gradient);
  z-index: 1;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 30% 30%, rgba(255, 107, 53, 0.1) 0%, transparent 40%),
    radial-gradient(circle at 70% 70%, rgba(255, 215, 0, 0.05) 0%, transparent 40%);
  z-index: 0;
}

.hero .container {
  position: relative;
  z-index: 2;
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--space-8);
}

.hero-avatar-wrapper {
  position: relative;
}

.hero-avatar {
  width: 200px;
  height: 200px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: 4px solid var(--color-primary);
  box-shadow: var(--shadow-glow);
  animation: avatarPulse 3s ease-in-out infinite;
}

@keyframes avatarPulse {
  0%, 100% {
    box-shadow: 0 0 30px rgba(255, 107, 53, 0.3);
  }
  50% {
    box-shadow: 0 0 50px rgba(255, 107, 53, 0.5);
  }
}

.hero-avatar-badge {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: var(--color-secondary);
  color: var(--bg-dark);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 700;
  box-shadow: var(--shadow-gold);
}

.hero-title {
  font-size: var(--text-6xl);
  background: linear-gradient(135deg, var(--text-primary), var(--color-primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: titleFadeIn 1s ease-out;
}

@keyframes titleFadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-subtitle {
  font-size: var(--text-xl);
  color: var(--text-secondary);
  max-width: 600px;
}

.hero-bio {
  max-width: 700px;
  color: var(--text-secondary);
  line-height: 1.8;
  font-size: var(--text-lg);
}

.hero-stats {
  display: flex;
  gap: var(--space-12);
  margin-top: var(--space-4);
}

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

.stat-value {
  font-size: var(--text-4xl);
  font-weight: 700;
  color: var(--color-primary);
  font-family: var(--font-heading);
}

.stat-label {
  font-size: var(--text-sm);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.hero-actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
  justify-content: center;
}

.hero-social {
  display: flex;
  gap: var(--space-4);
  margin-top: var(--space-4);
}

.social-link {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  font-size: var(--text-xl);
  transition: all var(--transition-base);
}

.social-link:hover {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--text-primary);
  transform: translateY(-3px);
  box-shadow: var(--shadow-glow);
}

@media (max-width: 768px) {
  .hero-title {
    font-size: var(--text-4xl);
  }
  
  .hero-avatar {
    width: 150px;
    height: 150px;
  }
  
  .hero-stats {
    gap: var(--space-6);
  }
  
  .stat-value {
    font-size: var(--text-2xl);
  }
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
  font-weight: 600;
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  cursor: pointer;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--text-primary);
  border: 2px solid var(--color-primary);
}

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

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 2px solid var(--border-color);
}

.btn-secondary:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-ghost {
  background: transparent;
  color: var(--color-primary);
  padding: var(--space-2) var(--space-4);
}

.btn-ghost:hover {
  background: rgba(255, 107, 53, 0.1);
}

/* ===== Cards ===== */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all var(--transition-base);
}

.card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-lg);
}

.card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card-content {
  padding: var(--space-6);
}

.card-category {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  background: rgba(255, 107, 53, 0.1);
  color: var(--color-primary);
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: var(--space-3);
}

.card-title {
  margin-bottom: var(--space-3);
  line-height: 1.4;
}

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

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

.card-excerpt {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  font-size: var(--text-sm);
  color: var(--text-muted);
}

.card-meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* ===== Articles Grid ===== */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
}

@media (max-width: 1024px) {
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .articles-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== Videos Section ===== */
.videos-grid {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: var(--space-8);
}

.video-featured {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
}

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

.video-featured-info {
  padding: var(--space-6);
}

.video-featured-title {
  margin-bottom: var(--space-2);
}

.video-featured-desc {
  color: var(--text-secondary);
  font-size: var(--text-sm);
}

.video-sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.video-thumb {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  cursor: pointer;
}

.video-thumb:hover {
  border-color: var(--color-primary);
  transform: translateX(5px);
}

.video-thumb-img {
  width: 120px;
  height: 70px;
  object-fit: cover;
  border-radius: var(--radius-md);
  flex-shrink: 0;
}

.video-thumb-info {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.video-thumb-title {
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: var(--space-1);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-thumb-meta {
  font-size: var(--text-xs);
  color: var(--text-muted);
}

.video-cta {
  margin-top: auto;
  padding: var(--space-6);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  text-align: center;
}

.video-cta-title {
  margin-bottom: var(--space-2);
  font-size: var(--text-lg);
}

.video-cta-stats {
  color: var(--text-muted);
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
}

@media (max-width: 1024px) {
  .videos-grid {
    grid-template-columns: 1fr;
  }
  
  .video-sidebar {
    flex-direction: row;
    flex-wrap: wrap;
  }
  
  .video-thumb {
    flex: 1 1 300px;
  }
  
  .video-cta {
    flex: 1 1 100%;
  }
}

/* ===== Predictions Section ===== */
.predictions-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  overflow: hidden;
}

.predictions-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-6);
  border-bottom: 1px solid var(--border-color);
}

.predictions-title {
  font-size: var(--text-xl);
}

.predictions-accuracy {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(16, 185, 129, 0.1);
  color: #10b981;
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
}

.predictions-list {
  padding: var(--space-4);
}

.prediction-item {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  border-bottom: 1px solid var(--border-color);
  transition: background var(--transition-fast);
}

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

.prediction-item:hover {
  background: var(--bg-card-hover);
}

.prediction-team {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.prediction-team.away {
  justify-content: flex-end;
}

.prediction-team.away .team-name {
  text-align: right;
}

.team-logo {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  object-fit: contain;
  background: var(--bg-glass);
  padding: 4px;
}

.team-name {
  font-weight: 600;
}

.prediction-vs {
  text-align: center;
  min-width: 100px;
}

.prediction-time {
  font-size: var(--text-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-1);
}

.prediction-date {
  font-size: var(--text-xs);
  color: var(--text-muted);
}

.prediction-result {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  min-width: 80px;
}

.prediction-score {
  padding: var(--space-2) var(--space-4);
  background: var(--color-primary);
  color: var(--text-primary);
  border-radius: var(--radius-lg);
  font-weight: 700;
  font-size: var(--text-lg);
}

.prediction-label {
  font-size: var(--text-xs);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

@media (max-width: 768px) {
  .prediction-item {
    grid-template-columns: 1fr;
    gap: var(--space-3);
    text-align: center;
  }
  
  .prediction-team {
    justify-content: center;
  }
  
  .prediction-team.away {
    justify-content: center;
  }
  
  .prediction-team.away .team-name {
    text-align: center;
  }
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  padding: var(--space-16) 0 var(--space-8);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer-brand {
  max-width: 300px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-xl);
  color: var(--text-primary);
}

.footer-desc {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: 1.8;
  margin-bottom: var(--space-6);
}

.footer-social {
  display: flex;
  gap: var(--space-3);
}

.footer-title {
  font-size: var(--text-base);
  margin-bottom: var(--space-6);
  color: var(--text-primary);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-link {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-8);
  border-top: 1px solid var(--border-color);
}

.footer-copyright {
  color: var(--text-muted);
  font-size: var(--text-sm);
}

.footer-legal {
  display: flex;
  gap: var(--space-6);
}

.footer-legal a {
  color: var(--text-muted);
  font-size: var(--text-sm);
}

@media (max-width: 1024px) {
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
  }
  
  .footer-brand {
    grid-column: span 2;
    max-width: none;
  }
}

@media (max-width: 640px) {
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-brand {
    grid-column: span 1;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }
}

/* ===== Scroll Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s ease-out;
}

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

/* ===== Utilities ===== */
.text-center { text-align: center; }
.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }

.mt-4 { margin-top: var(--space-4); }
.mt-8 { margin-top: var(--space-8); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-8 { margin-bottom: var(--space-8); }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.gap-4 { gap: var(--space-4); }
.gap-8 { gap: var(--space-8); }

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-dark);
}

::-webkit-scrollbar-thumb {
  background: var(--bg-card);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-primary);
}

/* ===== Selection ===== */
::selection {
  background: var(--color-primary);
  color: var(--text-primary);
}