/* ==========================================================================
   BASE.CSS - Space Invaders Retro Arcade Theme
   Modern CSS with retro gaming aesthetics, neon accents, and pixel-art style
   ========================================================================== */

/* ==========================================================================
   CSS VARIABLES
   ========================================================================== */

:root {
  /* Color Palette - Retro Arcade with Neon Accents */
  --color-background: #0a0e27;
  --color-background-light: #131829;
  --color-background-card: #1a1f3a;
  --color-text: #e0e6ff;
  --color-text-muted: #8b92b8;
  --color-primary: #00ff88;
  --color-primary-dark: #00cc6d;
  --color-primary-glow: rgba(0, 255, 136, 0.3);
  --color-secondary: #ff0099;
  --color-secondary-glow: rgba(255, 0, 153, 0.3);
  --color-accent: #00d4ff;
  --color-accent-glow: rgba(0, 212, 255, 0.3);
  --color-success: #00ff88;
  --color-warning: #ffaa00;
  --color-danger: #ff0055;
  --color-neutral-100: #f5f7ff;
  --color-neutral-200: #e0e6ff;
  --color-neutral-300: #c5cdeb;
  --color-neutral-400: #8b92b8;
  --color-neutral-500: #5a6186;
  --color-neutral-600: #3a4063;
  --color-neutral-700: #262b47;
  --color-neutral-800: #1a1f3a;
  --color-neutral-900: #0a0e27;

  /* Typography - Gaming Aesthetic */
  --font-primary: 'Press Start 2P', 'Courier New', monospace;
  --font-secondary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  --font-mono: 'Courier New', 'Courier', monospace;
  
  /* Font Sizes - Scalable System */
  --font-size-xs: 0.625rem;    /* 10px */
  --font-size-sm: 0.75rem;     /* 12px */
  --font-size-base: 0.875rem;  /* 14px */
  --font-size-md: 1rem;        /* 16px */
  --font-size-lg: 1.125rem;    /* 18px */
  --font-size-xl: 1.25rem;     /* 20px */
  --font-size-2xl: 1.5rem;     /* 24px */
  --font-size-3xl: 1.875rem;   /* 30px */
  --font-size-4xl: 2.25rem;    /* 36px */
  --font-size-5xl: 3rem;       /* 48px */

  /* Line Heights */
  --line-height-tight: 1.2;
  --line-height-normal: 1.6;
  --line-height-relaxed: 1.8;

  /* Spacing Scale */
  --space-0: 0;
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  --space-24: 6rem;     /* 96px */

  /* Border Radius - Minimal, Pixel-Art Style */
  --radius-none: 0;
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;
  --radius-full: 9999px;

  /* Shadows - Neon Glow Effects */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.6);
  --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.7);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.8);
  --shadow-glow-primary: 0 0 20px var(--color-primary-glow), 0 0 40px var(--color-primary-glow);
  --shadow-glow-secondary: 0 0 20px var(--color-secondary-glow), 0 0 40px var(--color-secondary-glow);
  --shadow-glow-accent: 0 0 20px var(--color-accent-glow), 0 0 40px var(--color-accent-glow);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 400ms ease-in-out;

  /* Layout */
  --container-max-width: 1200px;
  --container-padding: var(--space-4);
  --grid-gap: var(--space-6);
}

/* ==========================================================================
   RESET & NORMALIZE
   ========================================================================== */

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  overflow-x: hidden;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

input,
button,
textarea,
select {
  font: inherit;
}

ul,
ol {
  list-style: none;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

/* ==========================================================================
   BASE STYLES
   ========================================================================== */

body {
  font-family: var(--font-secondary);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(0, 255, 136, 0.03) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(255, 0, 153, 0.03) 0%, transparent 50%);
  background-attachment: fixed;
}

/* Headings */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-primary);
  line-height: var(--line-height-tight);
  font-weight: 400;
  color: var(--color-neutral-100);
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

h1 {
  font-size: var(--font-size-3xl);
  margin-bottom: var(--space-6);
  color: var(--color-primary);
  text-shadow: var(--shadow-glow-primary);
}

h2 {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--space-6);
  color: var(--color-accent);
}

h3 {
  font-size: var(--font-size-xl);
  margin-bottom: var(--space-4);
}

h4 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--space-3);
}

h5 {
  font-size: var(--font-size-base);
  margin-bottom: var(--space-3);
}

h6 {
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-2);
}

@media (min-width: 768px) {
  h1 {
    font-size: var(--font-size-4xl);
  }
  h2 {
    font-size: var(--font-size-3xl);
  }
  h3 {
    font-size: var(--font-size-2xl);
  }
}

/* Paragraphs */
p {
  margin-bottom: var(--space-4);
}

p:last-child {
  margin-bottom: 0;
}

/* Links */
a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
  cursor: pointer;
}

a:hover,
a:focus {
  color: var(--color-neutral-900);
  text-shadow: 0 0 8px var(--color-primary-glow);
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Strong & Emphasis */
strong,
b {
  font-weight: 700;
  color: var(--color-primary);
}

em,
i {
  font-style: italic;
  color: var(--color-accent);
}

/* Code */
code,
pre {
  font-family: var(--font-mono);
  background-color: var(--color-neutral-800);
  border: 1px solid var(--color-neutral-700);
  border-radius: var(--radius-sm);
}

code {
  padding: var(--space-1) var(--space-2);
  font-size: 0.9em;
  color: var(--color-accent);
}

pre {
  padding: var(--space-4);
  overflow-x: auto;
  margin-bottom: var(--space-4);
}

pre code {
  padding: 0;
  border: none;
  background: none;
}

/* Horizontal Rule */
hr {
  border: none;
  border-top: 2px solid var(--color-neutral-700);
  margin: var(--space-8) 0;
  box-shadow: 0 1px 0 var(--color-primary-glow);
}

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

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.container-fluid {
  width: 100%;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* Flexbox Utilities */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-wrap {
  flex-wrap: wrap;
}

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

.items-start {
  align-items: flex-start;
}

.items-end {
  align-items: flex-end;
}

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

.justify-between {
  justify-content: space-between;
}

.justify-around {
  justify-content: space-around;
}

.gap-2 {
  gap: var(--space-2);
}

.gap-4 {
  gap: var(--space-4);
}

.gap-6 {
  gap: var(--space-6);
}

.gap-8 {
  gap: var(--space-8);
}

/* Grid Utilities */
.grid {
  display: grid;
  gap: var(--grid-gap);
}

.grid-cols-1 {
  grid-template-columns: repeat(1, minmax(0, 1fr));
}

.grid-cols-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-cols-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-cols-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

@media (min-width: 768px) {
  .md\:grid-cols-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .md\:grid-cols-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .md\:grid-cols-4 {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* Text Alignment */
.text-left {
  text-align: left;
}

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

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

/* Screen Reader Only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Spacing Utilities */
.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); }
.my-4 { margin-top: var(--space-4); margin-bottom: var(--space-4); }
.my-8 { margin-top: var(--space-8); margin-bottom: var(--space-8); }
.mx-auto { margin-left: auto; margin-right: auto; }

.pt-4 { padding-top: var(--space-4); }
.pt-8 { padding-top: var(--space-8); }
.pb-4 { padding-bottom: var(--space-4); }
.pb-8 { padding-bottom: var(--space-8); }
.py-4 { padding-top: var(--space-4); padding-bottom: var(--space-4); }
.py-8 { padding-top: var(--space-8); padding-bottom: var(--space-8); }

/* ==========================================================================
   COMPONENTS
   ========================================================================== */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-primary);
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-background);
  background-color: var(--color-primary);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  box-shadow: var(--shadow-glow-primary), var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transition: left var(--transition-slow);
}

.btn:hover::before {
  left: 100%;
}

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

.btn:active {
  transform: translateY(0);
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 4px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

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

.btn-secondary {
  color: var(--color-background);
  background-color: var(--color-secondary);
  border-color: var(--color-secondary);
  box-shadow: var(--shadow-glow-secondary), var(--shadow-md);
}

.btn-secondary:hover,
.btn-secondary:focus {
  background-color: #cc007a;
  border-color: #cc007a;
  box-shadow: var(--shadow-glow-secondary), var(--shadow-lg);
}

.btn-outline {
  color: var(--color-primary);
  background-color: transparent;
  border-color: var(--color-primary);
  box-shadow: none;
}

.btn-outline:hover,
.btn-outline:focus {
  color: var(--color-background);
  background-color: var(--color-primary);
  box-shadow: var(--shadow-glow-primary), var(--shadow-md);
}

.btn-sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-xs);
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--font-size-sm);
}

/* Input Fields */
.input,
.textarea,
.select {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background-color: var(--color-background-light);
  border: 2px solid var(--color-neutral-700);
  border-radius: var(--radius-sm);
  transition: all var(--transition-base);
}

.input:hover,
.textarea:hover,
.select:hover {
  border-color: var(--color-neutral-600);
}

.input:focus,
.textarea:focus,
.select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-glow);
}

.input::placeholder,
.textarea::placeholder {
  color: var(--color-text-muted);
}

.input:disabled,
.textarea:disabled,
.select:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  background-color: var(--color-neutral-800);
}

.textarea {
  min-height: 120px;
  resize: vertical;
}

/* Card Component */
.card {
  background-color: var(--color-background-card);
  border: 1px solid var(--color-neutral-700);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary), var(--color-accent));
  opacity: 0;
  transition: opacity var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg), 0 0 20px var(--color-primary-glow);
  border-color: var(--color-neutral-600);
}

.card:hover::before {
  opacity: 1;
}

.card-title {
  font-family: var(--font-primary);
  font-size: var(--font-size-lg);
  color: var(--color-primary);
  margin-bottom: var(--space-3);
  text-transform: uppercase;
}

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

.card-footer {
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-neutral-700);
}

/* Badge Component */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  font-family: var(--font-primary);
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  color: var(--color-background);
  background-color: var(--color-primary);
  border-radius: var(--radius-full);
  box-shadow: 0 0 10px var(--color-primary-glow);
}

.badge-secondary {
  background-color: var(--color-secondary);
  box-shadow: 0 0 10px var(--color-secondary-glow);
}

.badge-accent {
  background-color: var(--color-accent);
  box-shadow: 0 0 10px var(--color-accent-glow);
}

/* Alert Component */
.alert {
  padding: var(--space-4) var(--space-6);
  border-left: 4px solid var(--color-primary);
  background-color: var(--color-background-card);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-4);
}

.alert-success {
  border-left-color: var(--color-success);
  background-color: rgba(0, 255, 136, 0.1);
}

.alert-warning {
  border-left-color: var(--color-warning);
  background-color: rgba(255, 170, 0, 0.1);
}

.alert-danger {
  border-left-color: var(--color-danger);
  background-color: rgba(255, 0, 85, 0.1);
}

/* Divider with Pixel Effect */
.divider {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
  margin: var(--space-8) 0;
  position: relative;
}

.divider::before,
.divider::after {
  content: '';
  position: absolute;
  top: -2px;
  width: 8px;
  height: 8px;
  background-color: var(--color-primary);
  box-shadow: 0 0 10px var(--color-primary-glow);
}

.divider::before {
  left: 0;
}

.divider::after {
  right: 0;
}

/* ==========================================================================
   ACCESSIBILITY
   ========================================================================== */

/* Focus Visible Outline */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --color-background: #000000;
    --color-text: #ffffff;
  }
  
  .btn,
  .card,
  .input {
    border-width: 3px;
  }
}

/* Dark Mode Support (already dark by default) */
@media (prefers-color-scheme: light) {
  /* Keep dark theme even in light mode preference for retro aesthetic */
}

/* ==========================================================================
   RESPONSIVE UTILITIES
   ========================================================================== */

@media (max-width: 767px) {
  :root {
    --container-padding: var(--space-3);
  }
  
  h1 {
    font-size: var(--font-size-2xl);
  }
  
  .btn {
    width: 100%;
  }
}

@media (min-width: 1024px) {
  :root {
    --font-size-base: 1rem;
  }
}

/* Print Styles */
@media print {
  body {
    background: white;
    color: black;
  }
  
  .btn,
  .card {
    box-shadow: none;
    border: 1px solid black;
  }
}