/* Asadin Edu Physics · Core Design System & Tokens */


:root {
  /* Color Palette: Cosmic Dark Space & Glowing Scientific Fields */
  --bg-darkest: #05070e;
  --bg-darker: #090d1a;
  --bg-dark: #0f172a;
  --bg-card: rgba(15, 23, 42, 0.75);
  --bg-card-hover: rgba(23, 34, 61, 0.85);
  --bg-glass: rgba(255, 255, 255, 0.04);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(0, 242, 254, 0.35);

  /* Scientific Accent Colors */
  --cyan-bright: #00f2fe;
  --azure-glow: #4facfe;
  --emerald-neon: #00f5d4;
  --amber-solar: #f6d365;
  --orange-thermo: #ff7a18;
  --violet-quantum: #b388ff;
  --purple-deep: #7028e4;
  --rose-relativity: #ff416c;

  /* Text & Typography */
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-accent: #00f2fe;

  --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'Fira Code', monospace;

  /* Shadows & Glows */
  --glow-cyan: 0 0 25px rgba(0, 242, 254, 0.25);
  --glow-amber: 0 0 25px rgba(246, 211, 101, 0.25);
  --glow-violet: 0 0 25px rgba(179, 136, 255, 0.25);
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);

  /* Layout Constants */
  --max-w: 1320px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  --nav-height: 72px;

  /* Transitions */
  --trans-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --trans-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: var(--font-body);
  background-color: var(--bg-darkest);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  background-image: 
    radial-gradient(ellipse at 15% 10%, rgba(0, 242, 254, 0.08), transparent 40%),
    radial-gradient(ellipse at 85% 30%, rgba(112, 40, 228, 0.08), transparent 45%),
    radial-gradient(circle at 50% 80%, rgba(246, 211, 101, 0.05), transparent 50%),
    radial-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 100% 100%, 32px 32px;
  overflow-x: hidden;
}

/* Typography Base */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

p {
  color: var(--text-secondary);
}

a {
  color: var(--cyan-bright);
  text-decoration: none;
  transition: color var(--trans-fast);
}

a:hover {
  color: #fff;
  text-shadow: 0 0 10px rgba(0, 242, 254, 0.6);
}

code, pre, .mono {
  font-family: var(--font-mono);
}

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

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

::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--cyan-bright);
}

/* Selection */
::selection {
  background: rgba(0, 242, 254, 0.3);
  color: #fff;
}