/* ===================================================== */
/*     EYE ONLINE GUIDE - DEEP SPACE DESIGN SYSTEM        */
/* ===================================================== */

:root {
  /* Primary - Deep Space */
  --primary-dark: #0A0A2A;
  --primary-mid: #12123C;
  --primary-light: #1A1A5E;
  
  /* Secondary - Nebulas */
  --nebula-purple: #7D26FF;
  --nebula-pink: #E84FD0;
  --nebula-orange: #FF6B35;
  --nebula-teal: #4DF5FF;
  --nebula-blue: #1DA1FF;
  
  /* Accent Color Palette */
  --accent-primary: #4DF5FF; /* Electric Teal */
  --accent-secondary: #FFD700; /* Starlight Gold */
  --accent-warning: #FF7B00; /* Alert Orange */
  --accent-success: #00FF9D; /* Mission Complete Green */
  
  /* Utility Colors */
  --text-primary: #E8F0FE;
  --text-secondary: #B8C4D8;
  --text-muted: #6B7894;
  --text-dark: #1A2236;
  --background-gradient-start: #0A0A2A;
  --background-gradient-end: #12123C;
  --card-bg: rgba(26, 26, 94, 0.8);
  --border-glow: rgba(77, 245, 255, 0.3);
  
  /* Shadows & Glow */
  --shadow-deep: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-glow-primary: 0 0 20px rgba(77, 245, 255, 0.2);
  --shadow-glow-secondary: 0 0 20px rgba(125, 38, 255, 0.2);
  --shadow-glow-accent: 0 0 30px rgba(77, 245, 255, 0.3);
  
  /* Typography */
  --font-display: 'Orbitron', 'Rajdhani', sans-serif; /* Futuristic headings */
  --font-body: 'Inter', 'Poppins', 'SF Pro Display', sans-serif; /* Body text */
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* ===================================================== */
/* GLOBAL RESET & BASE                                   */
/* ===================================================== */

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

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

body {
  font-family: var(--font-body);
  background: 
    radial-gradient(ellipse at 50% -20%, var(--primary-light) 0%, var(--primary-dark) 60%, var(--background-gradient-end) 100%),
    linear-gradient(
      90deg,
      transparent 48%,
      rgba(255, 255, 255, 0.03) 50%,
      transparent 52%
    );
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  background-size: 100% 100%, 50px 50px, 100% 100%;
  overflow-x: hidden;
}

/* ===================================================== */
/* PARTICLE EFFECT BACKGROUND                            */
/* ===================================================== */

.particle-field {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: var(--accent-primary);
  border-radius: 50%;
  opacity: 0.3;
  box-shadow: 0 0 10px var(--accent-primary);
  animation: twinkle var(--particle-duration) ease-in-out infinite;
}

.particle:nth-child(3n) { animation-duration: 3s; }
.particle:nth-child(3n+1) { animation-duration: 5s; }
.particle:nth-child(3n+2) { animation-duration: 7s; }

.particle::after {
  content: '';
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 2px;
  height: 10px;
  background: linear-gradient(to bottom,
    var(--accent-primary) 0%,
    transparent 100%
  );
  opacity: 0.6;
}

@keyframes twinkle {
  0%, 100% { opacity: 0.3; transform: scale(1); }
  50% { opacity: 0.7; transform: scale(1.2); }
}

@keyframes drift {
  0% { transform: translateX(-10px); }
  50% { transform: translateX(10px); }
  100% { transform: translateX(-10px); }
}

/* ===================================================== */
/* HEADER SECTION                                        */
/* ===================================================== */

.site-header {
  position: relative;
  z-index: 100;
  background: linear-gradient(180deg, rgba(10, 10, 42, 0.95) 0%, rgba(10, 10, 42, 0.7) 100%);
  border-bottom: 1px solid var(--border-glow);
  padding: 0 2rem;
  height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-glow-secondary);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-icon {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: conic-gradient(from 180deg,
    var(--nebula-purple) 0%,
    var(--nebula-blue) 33%,
    var(--nebula-teal) 66%,
    var(--nebula-purple) 100%
  );
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-glow-accent);
}

.logo-icon::before {
  content: '';
  width: 28px;
  height: 28px;
  border: 2px solid var(--text-primary);
  border-radius: 50%;
}

.logo-text {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  background: linear-gradient(90deg, 
    var(--accent-primary),
    var(--nebula-purple),
    var(--accent-primary)
  );
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: shimmer 3s linear infinite;
}

@keyframes shimmer {
  0% { background-position: 200% center; }
  100% { background-position: -200% center; }
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.header-nav button {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition-fast);
}

.header-nav button:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--border-glow);
}

.header-nav button.active {
  color: var(--accent-primary);
  background: rgba(77, 245, 255, 0.1);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow-primary);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* ===================================================== */
/* LANGUAGE SELECTOR                                     */
/* ===================================================== */

.language-selector {
  position: relative;
}

.language-select {
  appearance: none;
  background: var(--card-bg);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-sm);
  padding: 0.4rem 1rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.85rem;
  cursor: pointer;
  transition: var(--transition-fast);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='var(--accent-primary)' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
}

.language-select:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(77, 245, 255, 0.2);
}

.language-options {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-10px);
  background: var(--primary-light);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-sm);
  min-width: 160px;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition-normal);
  z-index: 1000;
  box-shadow: var(--shadow-deep);
}

.language-selector:focus-within .language-options {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.language-option {
  display: block;
  width: 100%;
  padding: 0.6rem 1rem;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.9rem;
  cursor: pointer;
  text-align: left;
  transition: var(--transition-fast);
}

.language-option:hover {
  background: rgba(77, 245, 255, 0.15);
}

.language-option.active {
  background: rgba(77, 245, 255, 0.2);
  color: var(--accent-primary);
}

/* ===================================================== */
/* MAIN LAYOUT                                          */
/* ===================================================== */

.main-layout {
  position: relative;
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: calc(100vh - 70px);
  gap: 2rem;
  padding: 0 2rem 4rem;
  z-index: 1;
}

@media (max-width: 1024px) {
  .main-layout {
    grid-template-columns: 1fr;
    padding: 0 1.5rem 2rem;
  }
  
  .side-nav.hidden-mobile {
    display: none;
  }
  
  .main-content {
    margin-top: 0;
  }
}

/* ===================================================== */
/* SIDE NAVIGATION                                       */
/* ===================================================== */

.side-nav {
  position: sticky;
  top: 70px;
  background: linear-gradient(180deg, 
    var(--card-bg) 0%,
    transparent 100%
  );
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1rem;
  backdrop-filter: blur(10px);
  max-height: calc(100vh - 70px);
  overflow-y: auto;
  box-shadow: var(--shadow-deep);
}

.nav-section {
  margin-bottom: 2rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 1.5rem;
}

.nav-section:last-child {
  margin-bottom: 0;
  border-bottom: none;
  padding-bottom: 0;
}

.nav-section-title {
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--accent-primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
  padding-left: 0.75rem;
  border-left: 3px solid var(--accent-primary);
}

.nav-link {
  display: block;
  width: 100%;
  padding: 0.75rem 1rem;
  margin: 0.25rem 0;
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition-fast);
  text-align: left;
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--accent-primary);
  opacity: 0;
  transition: var(--transition-fast);
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-primary);
  border-color: rgba(255, 255, 255, 0.1);
}

.nav-link:hover::before {
  opacity: 1;
}

.nav-link.active {
  background: linear-gradient(90deg,
    rgba(77, 245, 255, 0.2) 0%,
    transparent 100%
  );
  color: var(--accent-primary);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow-primary);
  padding-left: 1.4rem;
}

.nav-link.active::before {
  opacity: 1;
}

.nav-link .level-badge {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  font-size: 0.7rem;
  background: rgba(77, 245, 255, 0.2);
  color: var(--accent-primary);
  border-radius: 4px;
  font-weight: 600;
  margin-left: 0.75rem;
  vertical-align: super;
}

/* ===================================================== */
/* MAIN CONTENT AREA                                     */
/* ===================================================== */

.main-content {
  background: linear-gradient(180deg, 
    var(--card-bg) 0%,
    rgba(18, 18, 60, 0.5) 100%
  );
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-deep), var(--shadow-glow-secondary);
  padding: 2.5rem;
  min-height: calc(100vh - 70px - 80px);
  position: relative;
  overflow: hidden;
}

.content-header {
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-glow);
}

.content-title {
  font-family: var(--font-display);
  font-size: 2.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  background: linear-gradient(90deg,
    var(--text-primary),
    var(--accent-primary),
    var(--text-primary)
  );
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: shimmer 4s linear infinite;
}

.content-subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  font-weight: 400;
}

.content-body {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-secondary);
}

/* ===================================================== */
/* CONTENT CARDS                                         */
/* ===================================================== */

.content-card {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 1.5rem 0;
  transition: var(--transition-normal);
}

.content-card:hover {
  background: rgba(255, 255, 255, 0.04);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-primary);
}

.card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--accent-primary);
  margin-bottom: 1rem;
}

.card-description {
  color: var(--text-secondary);
}

/* ===================================================== */
/* BEGINNER SECTION SPECIFIC                             */
/* ===================================================== */

.beg-welcome {
  background: linear-gradient(135deg,
    rgba(77, 245, 255, 0.1) 0%,
    rgba(125, 38, 255, 0.1) 100%
  );
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2rem;
  margin-bottom: 2rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.beg-welcome::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(
    circle at center,
    transparent 0%,
    rgba(77, 245, 255, 0.05) 100%
  );
  animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

/* ===================================================== */
/* PARENTESIS BAR (PERMANENT STATUS INDICATOR)           */
/* ===================================================== */

.parenesis-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(90deg,
    var(--nebula-purple),
    var(--nebula-blue),
    var(--nebula-teal),
    var(--nebula-blue)
  );
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  border-top: 1px solid var(--border-glow);
  padding: 0.75rem 1.5rem;
  text-align: center;
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--accent-primary);
  backdrop-filter: blur(10px);
  box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.3);
  z-index: 1000;
  animation: shimmer 5s linear infinite;
}

.parenesis-bar .icon {
  display: inline-block;
  margin-right: 0.5rem;
  animation: spin 10s linear infinite;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* ===================================================== */
/* RESPONSIVE ADJUSTMENTS                                */
/* ===================================================== */

@media (max-width: 768px) {
  .site-header {
    padding: 0 1rem;
    height: 60px;
  }
  
  .main-layout {
    padding: 0 1rem 2rem;
    gap: 1rem;
  }
  
  .side-nav {
    padding: 1rem;
  }
  
  .content-title {
    font-size: 1.75rem;
    text-align: center;
  }
  
  .content-subtitle {
    font-size: 1rem;
  }
  
  .content-body {
    font-size: 0.95rem;
  }
  
  .content-card {
    padding: 1.25rem;
  }
  
  .parenesis-bar {
    font-size: 0.8rem;
    padding: 0.6rem 1rem;
  }
}

@media (max-width: 480px) {
  .site-header {
    padding: 0 0.75rem;
  }
  
  .header-logo {
    gap: 0.5rem;
  }
  
  .logo-icon {
    width: 36px;
    height: 36px;
  }
  
  .logo-text {
    font-size: 1.2rem;
  }
  
  .header-nav {
    gap: 0.25rem;
  }
  
  .header-nav button {
    padding: 0.4rem 0.75rem;
    font-size: 0.8rem;
  }
  
  .content-title {
    font-size: 1.5rem;
  }
}

/* ===================================================== */
/* UTILITY CLASSES                                        */
/* ===================================================== */

.text-accent { color: var(--accent-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }

.bg-glow {
  box-shadow: var(--shadow-glow-primary);
}

.border-glow {
  border-color: var(--border-glow);
}

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

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

::-webkit-scrollbar-thumb {
  background: var(--primary-light);
  border-radius: 4px;
}

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

/* ===================================================== */
/* Tables          */
/* ===================================================== */
table.centered-table td,
  table.centered-table th {
    text-align: center;
    border: 1px solid var(--border-glow); /* Optional: for visibility */
    padding: 10px;
  }

/* ===================================================== */
/* ANIMATIONS                                            */
/* ===================================================== */

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.content-card {
  animation: fadeIn 0.4s ease;
}

/* ===================================================== */
/* END DESIGN SYSTEM                                     */
/* ===================================================== */