/* ========================================
   PIXEL360 DESIGN - BASE CSS
   Corporate • Cinematic • Technical
   ======================================== */

/* ========================================
   1. VARIABLES
   ======================================== */
:root {
  /* Colors - Deep Charcoal & Electric Accents */
  --color-bg: #0a0a0f;
  --color-bg-elevated: #141419;
  --color-bg-surface: #1a1a20;
  --color-bg-overlay: rgba(10, 10, 15, 0.85);
  
  --color-text: #f4f4f5;
  --color-text-secondary: #a1a1aa;
  --color-text-muted: #71717a;
  
  --color-primary: #00d9ff;
  --color-primary-hover: #33e0ff;
  --color-primary-glow: rgba(0, 217, 255, 0.4);
  
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-danger: #ef4444;
  
  /* Neutral Grays - Slate Scale */
  --color-neutral-50: #fafafa;
  --color-neutral-100: #f4f4f5;
  --color-neutral-200: #e4e4e7;
  --color-neutral-300: #d4d4d8;
  --color-neutral-400: #a1a1aa;
  --color-neutral-500: #71717a;
  --color-neutral-600: #52525b;
  --color-neutral-700: #3f3f46;
  --color-neutral-800: #27272a;
  --color-neutral-900: #18181b;
  
  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, Monaco, monospace;
  
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.625vw, 1.25rem);
  --text-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);
  --text-2xl: clamp(1.5rem, 1.3rem + 1vw, 2rem);
  --text-3xl: clamp(1.875rem, 1.6rem + 1.375vw, 2.5rem);
  --text-4xl: clamp(2.25rem, 1.9rem + 1.75vw, 3rem);
  --text-5xl: clamp(3rem, 2.5rem + 2.5vw, 4rem);
  --text-6xl: clamp(3.75rem, 3rem + 3.75vw, 5rem);
  
  --leading-none: 1;
  --leading-tight: 1.2;
  --leading-snug: 1.375;
  --leading-normal: 1.6;
  --leading-relaxed: 1.75;
  
  /* Spacing Scale - 0 to 96px */
  --space-0: 0;
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.25rem;   /* 20px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-10: 2.5rem;   /* 40px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  --space-24: 6rem;     /* 96px */
  
  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows - Cinematic Depth */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.6), 0 4px 6px -4px rgba(0, 0, 0, 0.4);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.7), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 30px var(--color-primary-glow);
  --shadow-glow-sm: 0 0 15px var(--color-primary-glow);
  --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.4);
  
  /* Transitions - Micro-interactions */
  --duration-instant: 100ms;
  --duration-fast: 150ms;
  --duration-normal: 250ms;
  --duration-slow: 350ms;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  
  /* Effects */
  --backdrop-blur: blur(12px);
  --border-subtle: rgba(255, 255, 255, 0.06);
}

/* ========================================
   2. RESET & NORMALIZE
   ======================================== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

@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;
  }
}

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

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

button {
  cursor: pointer;
  background: none;
  border: none;
}

ul,
ol {
  list-style: none;
}

/* ========================================
   3. BASE STYLES
   ======================================== */
body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  font-weight: 400;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: var(--leading-tight);
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-4xl); }
h3 { font-size: var(--text-3xl); }
h4 { font-size: var(--text-2xl); }
h5 { font-size: var(--text-xl); }
h6 { font-size: var(--text-lg); }

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-secondary);
  }

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

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

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  color: var(--color-primary);
  background: var(--color-bg-surface);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-sm);
}

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

@media (min-width: 640px) {
  .container {
    padding-left: var(--space-6);
    padding-right: var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding-left: var(--space-8);
    padding-right: var(--space-8);
  }
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.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;
}

.text-gradient {
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ========================================
   5. COMPONENTS
   ======================================== */

/* 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-sm);
  font-weight: 600;
  letter-spacing: 0.025em;
  border-radius: var(--radius-md);
  transition: all var(--duration-normal) var(--ease-out);
  position: relative;
  overflow: hidden;
  white-space: nowrap;
}

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

.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-bg);
  box-shadow: var(--shadow-glow-sm);
}

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

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

.btn-secondary {
  background-color: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-neutral-700);
}

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

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none !important;
  box-shadow: none !important;
}

/* Inputs */
.input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  background-color: var(--color-bg-elevated);
  border: 1px solid var(--color-neutral-800);
  border-radius: var(--radius-md);
  color: var(--color-text);
  transition: all var(--duration-normal) var(--ease-out);
  outline: none;
}

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

.input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-glow);
}

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

.input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Cards */
.card {
  background-color: var(--color-bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-lg);
  transition: transform var(--duration-normal) var(--ease-out),
              box-shadow var(--duration-normal) var(--ease-out),
              border-color var(--duration-normal) var(--ease-out);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(255, 255, 255, 0.1);
}

.card-interactive {
  cursor: pointer;
}

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

@media (prefers-reduced-motion: reduce) {
  .btn,
  .input,
  .card,
  a {
    transition: none;
  }
  
  .btn:hover,
  .card:hover {
    transform: none;
  }
}