/* CSS Variables - Professional Design System */
:root {
    /* Colors - Professional palette */
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #3b82f6;

    --color-secondary: #64748b;
    --color-secondary-dark: #475569;
    --color-secondary-light: #94a3b8;

    --color-success: #059669;
    --color-success-dark: #047857;
    --color-success-light: #10b981;

    --color-warning: #d97706;
    --color-warning-dark: #b45309;
    --color-warning-light: #f59e0b;

    --color-danger: #dc2626;
    --color-danger-dark: #b91c1c;
    --color-danger-light: #ef4444;

    /* Gray scale */
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    /* Background colors */
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f8f9fa;
    --color-bg-tertiary: #f1f3f4;
    --color-bg-dark: #2c3e50;

    /* Text colors */
    --color-text-primary: #2c3e50;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-text-white: #ffffff;

    /* Border colors */
    --color-border-light: #e2e8f0;
    --color-border-medium: #cbd5e0;
    --color-border-dark: #a0aec0;

    /* Typography */
    --font-family-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-family-mono: 'SF Mono', Monaco, Inconsolata, 'Roboto Mono', Consolas, 'Courier New', monospace;

    --font-size-xs: 0.75rem;
    /* 12px */
    --font-size-sm: 0.875rem;
    /* 14px */
    --font-size-base: 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-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;

    /* Spacing */
    --spacing-1: 0.25rem;
    /* 4px */
    --spacing-2: 0.5rem;
    /* 8px */
    --spacing-3: 0.75rem;
    /* 12px */
    --spacing-4: 1rem;
    /* 16px */
    --spacing-5: 1.25rem;
    /* 20px */
    --spacing-6: 1.5rem;
    /* 24px */
    --spacing-8: 2rem;
    /* 32px */
    --spacing-10: 2.5rem;
    /* 40px */
    --spacing-12: 3rem;
    /* 48px */
    --spacing-16: 4rem;
    /* 64px */
    --spacing-20: 5rem;
    /* 80px */
    --spacing-24: 6rem;
    /* 96px */

    /* Border radius */
    --border-radius-sm: 0.125rem;
    /* 2px */
    --border-radius-base: 0.25rem;
    /* 4px */
    --border-radius-md: 0.375rem;
    /* 6px */
    --border-radius-lg: 0.5rem;
    /* 8px */
    --border-radius-xl: 0.75rem;
    /* 12px */
    --border-radius-2xl: 1rem;
    /* 16px */
    --border-radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-base: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.06);

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 200ms ease-in-out;
    --transition-slow: 300ms ease-in-out;

    /* Z-index layers */
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;
    --z-toast: 1080;

    /* Layout */
    --header-height: 64px;
    --sidebar-width: 240px;
    --sidebar-collapsed-width: 60px;

    /* Breakpoints (for reference in JS) */
    --breakpoint-sm: 576px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 992px;
    --breakpoint-xl: 1200px;
    --breakpoint-2xl: 1400px;
}