/* 
   --------------------------------------------------------------------------
   1. VARIABLES
   --------------------------------------------------------------------------
*/
:root {
  /* Colors - Automotive Dark Palette (Matte Black, Gunmetal, Crimson, Neon Blue) */
  --color-bg: #0a0a0a;
  --color-surface: #161618;
  --color-surface-hover: #1f1f22;
  --color-text: #f0f0f0;
  --color-text-muted: #9ca3af;
  --color-primary: #dc143c;
  --color-primary-hover: #b01030;
  --color-accent: #00f0ff;
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-danger: #ef4444;
  --color-border: #2e2e33;

  /* Typography */
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
  
  --size-xs: 0.75rem;
  --size-sm: 0.875rem;
  --size-base: 1rem;
  --size-lg: 1.125rem;
  --size-xl: 1.25rem;
  --size-2xl: 1.5rem;
  --size-3xl: 1.875rem;
  --size-4xl: 2.25rem;

  --leading-tight: 1.2;
  --leading-base: 1.5;
  --leading-relaxed: 1.75;

  /* Spacing Scale */
  --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-24: 6rem;    /* 96px */

  /* UI Properties */
  --radius-sm: 2px;    /* Sharper corners for technical feel */
  --radius-md: 4px;
  --radius-lg: 8px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 15px rgba(0, 240, 255, 0.15);

  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
}

/* 
   --------------------------------------------------------------------------
   2. RESET / NORMALIZE
   --------------------------------------------------------------------------
*/
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--size-base);
  line-height: var(--leading-base);
  background-color: var(--color-bg);
  color: var(--color-text);
  -webkit-font-smoothing: antialiased;
}

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

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

/* 
   --------------------------------------------------------------------------
   3. BASE STYLES
   --------------------------------------------------------------------------
*/
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: var(--leading-tight);
  margin-top: 0;
  margin-bottom: var(--space-4);
  color: var(--color-text);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

h1 { font-size: var(--size-4xl); }
h2 { font-size: var(--size-3xl); }
h3 { font-size: var(--size-2xl); }
h4 { font-size: var(--size-xl); }

p {
  margin-top: 0;
  margin-bottom: var(--space-4);
  color: var(--color-text-muted);
}

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

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

/* 
   --------------------------------------------------------------------------
   4. UTILITIES
   --------------------------------------------------------------------------
*/
.container {
  width: 100%;
  max-width: 1280px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

.flex {
  display: flex;
}

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

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

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

.grid {
  display: grid;
}

.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;
}

/* 
   --------------------------------------------------------------------------
   5. COMPONENTS
   --------------------------------------------------------------------------
*/

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-3) var(--space-6);
  font-weight: 600;
  font-size: var(--size-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  line-height: 1;
}

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

.btn-primary:hover {
  background-color: var(--color-primary-hover);
  box-shadow: 0 0 10px rgba(220, 20, 60, 0.4);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--color-border);
  color: var(--color-text);
}

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

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

/* Inputs */
.input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  transition: border-color var(--transition-fast);
}

.input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 1px var(--color-accent);
}

/* Cards */
.card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.card:hover {
  border-color: var(--color-border);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* 
   --------------------------------------------------------------------------
   6. ACCESSIBILITY
   --------------------------------------------------------------------------
*/
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

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