/* ============================================
   TRADEVISION - PROFESSIONAL BLACK & WHITE THEME
   Enterprise B2B Software Company Design System
   Zero Compromises - 60 FPS - < 500ms Load
   ============================================ */

/* ============================================
   1. CSS CUSTOM PROPERTIES (Design Tokens)
   ============================================ */

:root {
    /* Primary Colors - Black Scale */
    --color-black-pure: #000000;           /* Pure Black */
    --color-black-soft: #0a0a0a;           /* Soft Black */
    --color-black-light: #1a1a1a;          /* Light Black */
    --color-black-medium: #2a2a2a;         /* Medium Black */

    /* Primary Colors - White Scale */
    --color-white-pure: #ffffff;           /* Pure White */
    --color-white-off: #f8f8f8;            /* Off White */
    --color-white-light: #f0f0f0;          /* Light Gray */

    /* Accent Colors - Gray Scale */
    --color-gray-darkest: #333333;         /* Darkest Gray */
    --color-gray-dark: #666666;            /* Dark Gray */
    --color-gray-medium: #999999;          /* Medium Gray */
    --color-gray-light: #cccccc;           /* Light Gray */
    --color-gray-lightest: #e0e0e0;        /* Lightest Gray */

    /* Functional Colors - Desaturated */
    --color-success: #10b981;              /* Success Green */
    --color-warning: #f59e0b;              /* Warning Amber */
    --color-error: #ef4444;                /* Error Red */
    --color-info: #3b82f6;                 /* Info Blue */

    /* DARK MODE - Default Theme */
    --color-primary: var(--color-white-pure);
    --color-secondary: var(--color-gray-light);
    --color-accent: var(--color-gray-medium);
    --color-background: var(--color-black-soft);
    --color-surface: var(--color-black-light);
    --color-text-primary: var(--color-white-pure);
    --color-text-secondary: var(--color-gray-light);
    --color-text-tertiary: var(--color-gray-medium);
    --color-border-default: var(--color-gray-darkest);
    --color-border-focus: var(--color-white-pure);

    /* Opacity Variants */
    --opacity-5: 0.05;
    --opacity-10: 0.10;
    --opacity-20: 0.20;
    --opacity-30: 0.30;
    --opacity-50: 0.50;
    --opacity-70: 0.70;

    /* Shadow System - 8 Levels */
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 12px 24px rgba(0, 0, 0, 0.18);
    --shadow-2xl: 0 16px 32px rgba(0, 0, 0, 0.20);
    --shadow-3xl: 0 24px 48px rgba(0, 0, 0, 0.25);
    --shadow-inner: inset 0 2px 4px rgba(0, 0, 0, 0.06);

    /* Spacing System - 4px Base Unit */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-6: 24px;
    --space-8: 32px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;
    --space-24: 96px;

    /* Typography Scale - 12 Steps */
    --font-size-xs: 0.625rem;    /* 10px */
    --font-size-sm: 0.75rem;     /* 12px */
    --font-size-base: 0.875rem;  /* 14px */
    --font-size-md: 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-size-5xl: 3rem;       /* 48px */
    --font-size-6xl: 3.75rem;    /* 60px */
    --font-size-7xl: 4rem;       /* 64px */

    /* Line Heights */
    --line-height-none: 1;
    --line-height-tight: 1.25;
    --line-height-snug: 1.375;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.625;
    --line-height-loose: 2;

    /* Font Weights */
    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;

    /* Border Radius */
    --radius-none: 0;
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 24px;
    --radius-full: 9999px;

    /* Transitions - Cubic Bezier for 60 FPS */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-medium: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Z-Index Scale */
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;

    /* Breakpoints (for JS) */
    --breakpoint-xs: 320px;
    --breakpoint-sm: 480px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 1024px;
    --breakpoint-xl: 1440px;
    --breakpoint-2xl: 1920px;
}

/* ============================================
   LIGHT MODE (Optional Toggle)
   ============================================ */

:root[data-theme="light"] {
    --color-primary: var(--color-black-pure);
    --color-secondary: var(--color-gray-darkest);
    --color-accent: var(--color-gray-dark);
    --color-background: var(--color-white-pure);
    --color-surface: var(--color-white-off);
    --color-text-primary: var(--color-black-pure);
    --color-text-secondary: var(--color-gray-dark);
    --color-text-tertiary: var(--color-gray-medium);
    --color-border-default: var(--color-gray-lightest);
    --color-border-focus: var(--color-black-pure);
}

/* ============================================
   2. GLOBAL RESET & BASE STYLES
   ============================================ */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    font-size: var(--font-size-md);
    line-height: var(--line-height-normal);
    color: var(--color-text-primary);
    background-color: var(--color-background);
    min-height: 100vh;
    overflow-x: hidden;
}

/* ============================================
   3. TYPOGRAPHY SYSTEM
   ============================================ */

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

h1 {
    font-size: clamp(var(--font-size-3xl), 5vw, var(--font-size-7xl));
    font-weight: var(--font-weight-extrabold);
}

h2 {
    font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-5xl));
}

h3 {
    font-size: clamp(var(--font-size-xl), 3vw, var(--font-size-4xl));
}

h4 {
    font-size: clamp(var(--font-size-lg), 2.5vw, var(--font-size-3xl));
}

h5 {
    font-size: clamp(var(--font-size-md), 2vw, var(--font-size-2xl));
}

h6 {
    font-size: clamp(var(--font-size-base), 1.5vw, var(--font-size-xl));
}

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

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

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

a:focus-visible {
    outline: 2px solid var(--color-border-focus);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* ============================================
   4. CONTAINER & LAYOUT
   ============================================ */

.container {
    width: 100%;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

.container-fluid {
    width: 100%;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

/* ============================================
   5. GRID SYSTEM (12 Column)
   ============================================ */

.grid {
    display: grid;
    gap: var(--space-6);
}

.grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
.grid-cols-6 { grid-template-columns: repeat(6, 1fr); }
.grid-cols-12 { grid-template-columns: repeat(12, 1fr); }

/* ============================================
   6. FLEXBOX UTILITIES
   ============================================ */

.flex { display: flex; }
.flex-inline { display: inline-flex; }
.flex-row { flex-direction: row; }
.flex-column { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.flex-nowrap { flex-wrap: nowrap; }

.items-start { align-items: flex-start; }
.items-center { align-items: center; }
.items-end { align-items: flex-end; }
.items-stretch { align-items: stretch; }

.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

/* ============================================
   7. SPACING UTILITIES
   ============================================ */

.m-0 { margin: 0; }
.m-1 { margin: var(--space-1); }
.m-2 { margin: var(--space-2); }
.m-4 { margin: var(--space-4); }
.m-6 { margin: var(--space-6); }
.m-8 { margin: var(--space-8); }

.mt-0 { margin-top: 0; }
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }

.mb-0 { margin-bottom: 0; }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }

.p-0 { padding: 0; }
.p-2 { padding: var(--space-2); }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }
.p-8 { padding: var(--space-8); }

/* ============================================
   8. RESPONSIVE BREAKPOINTS
   ============================================ */

@media (max-width: 767px) {
    .container {
        padding-left: var(--space-4);
        padding-right: var(--space-4);
    }

    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }
}

@media (min-width: 768px) {
    .md\:grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
    .md\:grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
}

@media (min-width: 1024px) {
    .lg\:grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
    .lg\:grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
}

/* ============================================
   9. ACCESSIBILITY & REDUCED MOTION
   ============================================ */

@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;
    }
}

.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;
}

/* ============================================
   10. FOCUS INDICATORS (WCAG 2.1 AA)
   ============================================ */

*:focus-visible {
    outline: 2px solid var(--color-border-focus);
    outline-offset: 4px;
    border-radius: var(--radius-sm);
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 2px solid var(--color-border-focus);
    outline-offset: 2px;
}

/* ============================================
   11. PRINT STYLES
   ============================================ */

@media print {
    *,
    *::before,
    *::after {
        background: transparent !important;
        color: black !important;
        box-shadow: none !important;
        text-shadow: none !important;
    }

    a,
    a:visited {
        text-decoration: underline;
    }

    img {
        page-break-inside: avoid;
    }

    h2, h3 {
        page-break-after: avoid;
    }
}