:root {
  /* Core Colors - Green Theme */
  --primary-color: #00C853;
  /* A vibrant, emerald green */
  --primary-hover: #00E676;
  --primary-dim: rgba(0, 200, 83, 0.1);

  /* Typography */
  --font-main: 'Outfit', 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'Fira Code', monospace;

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 4rem;

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode (Default) */
:root {
  --bg-body: #0A0A0A;
  /* Deep black context */
  --bg-surface: #141414;
  --bg-glass: rgba(20, 20, 20, 0.7);
  --text-main: #FFFFFF;
  --text-muted: #A0A0A0;
  --border-color: #333333;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.5);
}

/* Light Mode */
[data-theme="light"] {
  --bg-body: #F8F9FA;
  --bg-surface: #FFFFFF;
  --bg-glass: rgba(255, 255, 255, 0.7);
  --text-main: #1A1A1A;
  --text-muted: #666666;
  --border-color: #E5E5E5;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.08);
}

/* Global Reset & Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-body);
  color: var(--text-main);
  transition: background-color var(--transition-normal), color var(--transition-normal);
  line-height: 1.6;
}

a {
  color: inherit;
  text-decoration: none;
}

/* Utility */
.glass-panel {
  background: var(--bg-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: 16px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.btn-primary {
  background: var(--primary-color);
  color: #000;
  /* Contrast black on green is usually better/more clear than white on light green */
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--primary-dim);
}