/* =============================================================================
   Raj IT Custom - Main CSS Framework
   Built with Test-Driven Development (TDD) approach
   ============================================================================= */

/* =============================================================================
   CSS Reset & Base Styles
   ============================================================================= */

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

html {
    font-size: 16px;
    line-height: 1.6;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-weight: 400;
    color: var(--color-text);
    background-color: var(--color-background);
    overflow-x: hidden;
}

/* =============================================================================
   CSS Custom Properties (Design System)
   ============================================================================= */

:root {
    /* Colors */
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-primary-light: #dbeafe;
    --color-secondary: #64748b;
    --color-accent: #f59e0b;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;

    /* Text Colors */
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-text-white: #ffffff;

    /* Background Colors */
    --color-background: #ffffff;
    --color-background-light: #f9fafb;
    --color-background-dark: #111827;

    /* Border Colors */
    --color-border: #e5e7eb;
    --color-border-light: #f3f4f6;
    --color-border-dark: #374151;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;

    /* Typography */
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --font-size-6xl: 3.75rem;

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

    /* Line Heights */
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.625;
    --line-height-loose: 2;

    /* Border Radius */
    --radius-sm: 0.125rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --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);

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;

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

    /* Container */
    --container-max-width: 1200px;
    --container-padding: var(--spacing-md);
}

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
    :root {
        --color-text: #f9fafb;
        --color-text-light: #d1d5db;
        --color-background: #111827;
        --color-background-light: #1f2937;
        --color-border: #374151;
        --color-border-light: #4b5563;
    }
}

/* =============================================================================
   Layout & Grid System
   ============================================================================= */

.container {
    width: 100%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.container-fluid {
    width: 100%;
    padding: 0 var(--container-padding);
}

/* Grid System */
.grid {
    display: grid;
    gap: var(--spacing-md);
}

.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); }

/* Responsive Grid */
@media (max-width: 768px) {
    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4,
    .grid-cols-6,
    .grid-cols-12 {
        grid-template-columns: 1fr;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .grid-cols-3,
    .grid-cols-4,
    .grid-cols-6,
    .grid-cols-12 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Flexbox Utilities */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.items-center {
    align-items: center;
}

.items-start {
    align-items: flex-start;
}

.items-end {
    align-items: flex-end;
}

.justify-center {
    justify-content: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-around {
    justify-content: space-around;
}

.justify-end {
    justify-content: flex-end;
}

/* =============================================================================
   Typography
   ============================================================================= */

h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
}

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

p {
    margin-bottom: var(--spacing-md);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-light);
}

.text-xs { font-size: var(--font-size-xs); }
.text-sm { font-size: var(--font-size-sm); }
.text-base { font-size: var(--font-size-base); }
.text-lg { font-size: var(--font-size-lg); }
.text-xl { font-size: var(--font-size-xl); }
.text-2xl { font-size: var(--font-size-2xl); }
.text-3xl { font-size: var(--font-size-3xl); }
.text-4xl { font-size: var(--font-size-4xl); }
.text-5xl { font-size: var(--font-size-5xl); }

.font-light { font-weight: var(--font-weight-light); }
.font-normal { font-weight: var(--font-weight-normal); }
.font-medium { font-weight: var(--font-weight-medium); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

/* =============================================================================
   Buttons
   ============================================================================= */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    line-height: 1;
    text-decoration: none;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    user-select: none;
}

.btn:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Button Sizes */
.btn-sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: var(--font-size-xs);
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-base);
}

.btn-full {
    width: 100%;
}

/* Button Variants */
.btn-primary {
    background-color: var(--color-primary);
    color: var(--color-text-white);
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background-color: var(--color-primary-hover);
    border-color: var(--color-primary-hover);
}

.btn-outline {
    background-color: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-outline:hover {
    background-color: var(--color-primary);
    color: var(--color-text-white);
}

.btn-white {
    background-color: var(--color-text-white);
    color: var(--color-text);
    border-color: var(--color-text-white);
}

.btn-white:hover {
    background-color: var(--color-background-light);
}

.btn-outline-white {
    background-color: transparent;
    color: var(--color-text-white);
    border-color: var(--color-text-white);
}

.btn-outline-white:hover {
    background-color: var(--color-text-white);
    color: var(--color-text);
}

/* =============================================================================
   Forms
   ============================================================================= */

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text);
    margin-bottom: var(--spacing-sm);
}

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-base);
    font-family: inherit;
    color: var(--color-text);
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--color-text-light);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-error {
    color: var(--color-error);
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

/* =============================================================================
   Cards
   ============================================================================= */

.card {
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border-light);
}

.card-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-sm);
}

.card-body {
    margin-bottom: var(--spacing-lg);
}

.card-footer {
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-border-light);
}

/* =============================================================================
   Navigation
   ============================================================================= */

.nav-link {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-light);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
}

/* =============================================================================
   Utilities
   ============================================================================= */

/* Spacing */
.m-0 { margin: 0; }
.mt-0 { margin-top: 0; }
.mr-0 { margin-right: 0; }
.mb-0 { margin-bottom: 0; }
.ml-0 { margin-left: 0; }

.m-1 { margin: var(--spacing-xs); }
.mt-1 { margin-top: var(--spacing-xs); }
.mr-1 { margin-right: var(--spacing-xs); }
.mb-1 { margin-bottom: var(--spacing-xs); }
.ml-1 { margin-left: var(--spacing-xs); }

.m-2 { margin: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-sm); }
.mr-2 { margin-right: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.ml-2 { margin-left: var(--spacing-sm); }

.m-4 { margin: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-md); }
.mr-4 { margin-right: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-md); }
.ml-4 { margin-left: var(--spacing-md); }

.p-0 { padding: 0; }
.pt-0 { padding-top: 0; }
.pr-0 { padding-right: 0; }
.pb-0 { padding-bottom: 0; }
.pl-0 { padding-left: 0; }

.p-1 { padding: var(--spacing-xs); }
.pt-1 { padding-top: var(--spacing-xs); }
.pr-1 { padding-right: var(--spacing-xs); }
.pb-1 { padding-bottom: var(--spacing-xs); }
.pl-1 { padding-left: var(--spacing-xs); }

.p-2 { padding: var(--spacing-sm); }
.pt-2 { padding-top: var(--spacing-sm); }
.pr-2 { padding-right: var(--spacing-sm); }
.pb-2 { padding-bottom: var(--spacing-sm); }
.pl-2 { padding-left: var(--spacing-sm); }

.p-4 { padding: var(--spacing-md); }
.pt-4 { padding-top: var(--spacing-md); }
.pr-4 { padding-right: var(--spacing-md); }
.pb-4 { padding-bottom: var(--spacing-md); }
.pl-4 { padding-left: var(--spacing-md); }

/* Display */
.block { display: block; }
.inline-block { display: inline-block; }
.inline { display: inline; }
.hidden { display: none; }

/* Position */
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; }

/* Width & Height */
.w-full { width: 100%; }
.h-full { height: 100%; }
.min-h-screen { min-height: 100vh; }

/* Colors */
.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-error { color: var(--color-error); }

.bg-primary { background-color: var(--color-primary); }
.bg-light { background-color: var(--color-background-light); }
.bg-white { background-color: var(--color-background); }

/* Border */
.border { border: 1px solid var(--color-border); }
.border-t { border-top: 1px solid var(--color-border); }
.border-r { border-right: 1px solid var(--color-border); }
.border-b { border-bottom: 1px solid var(--color-border); }
.border-l { border-left: 1px solid var(--color-border); }

.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-full { border-radius: var(--radius-full); }

/* Shadow */
.shadow { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-none { box-shadow: none; }

/* =============================================================================
   Accessibility
   ============================================================================= */

.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--color-primary);
    color: var(--color-text-white);
    padding: 8px;
    text-decoration: none;
    z-index: var(--z-tooltip);
    border-radius: var(--radius-md);
}

.skip-link:focus {
    top: 6px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* =============================================================================
   Animations
   ============================================================================= */

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
    from { transform: translateX(-100%); }
    to { transform: translateX(0); }
}

.animate-fade-in {
    animation: fadeIn 0.6s ease-out;
}

.animate-slide-in {
    animation: slideIn 0.3s ease-out;
}

/* =============================================================================
   Responsive Design
   ============================================================================= */

/* Mobile First Approach */
@media (max-width: 640px) {
    :root {
        --container-padding: var(--spacing-md);
        --font-size-4xl: 2rem;
        --font-size-3xl: 1.5rem;
        --font-size-2xl: 1.25rem;
    }

    .container {
        padding: 0 var(--spacing-md);
    }

    h1 { font-size: var(--font-size-3xl); }
    h2 { font-size: var(--font-size-2xl); }
    h3 { font-size: var(--font-size-xl); }
}

@media (min-width: 641px) and (max-width: 768px) {
    :root {
        --container-padding: var(--spacing-lg);
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    :root {
        --container-padding: var(--spacing-xl);
    }
}

@media (min-width: 1025px) {
    :root {
        --container-padding: var(--spacing-2xl);
    }
}

/* 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;
    }

    .btn {
        border: 1px solid black;
        background: transparent;
        color: black;
    }

    .hidden-print {
        display: none !important;
    }
}