/* ========================================
   BITS CONSULTANCY - MAIN STYLESHEET
   Global Styles, CSS Variables, Reset
   ======================================== */

/* CSS Variables - Easy Theme Customization */
:root {
  /* Colors */
  --color-primary: #0A2463;
  --color-primary-dark: #07183F;
  --color-primary-light: #1A3A7A;
  --color-accent: #00D4FF;
  --color-accent-dark: #00B8E6;
  --color-success: #10B981;
  --color-success-light: #34D399;
  
  /* Neutral Colors */
  --color-bg: #F9FAFB;
  --color-bg-white: #FFFFFF;
  --color-text: #1F2937;
  --color-text-light: #6B7280;
  --color-text-lighter: #9CA3AF;
  --color-border: #E5E7EB;
  --color-border-light: #F3F4F6;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #0A2463 0%, #1A3A7A 100%);
  --gradient-accent: linear-gradient(135deg, #00D4FF 0%, #00B8E6 100%);
  --gradient-ai: linear-gradient(135deg, #0A2463 0%, #00D4FF 100%);
  
  /* Typography */
  --font-display: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Type Scale */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-base: 1rem;     /* 16px */
  --text-lg: 1.125rem;   /* 18px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;   /* 36px */
  --text-5xl: 3rem;      /* 48px */
  --text-6xl: 3.75rem;   /* 60px */
  
  /* Spacing System (8px base grid) */
  --space-1: 0.5rem;     /* 8px */
  --space-2: 1rem;       /* 16px */
  --space-3: 1.5rem;     /* 24px */
  --space-4: 2rem;       /* 32px */
  --space-5: 2.5rem;     /* 40px */
  --space-6: 3rem;       /* 48px */
  --space-8: 4rem;       /* 64px */
  --space-10: 5rem;      /* 80px */
  --space-12: 6rem;      /* 96px */
  --space-15: 7.5rem;    /* 120px */
  
  /* Layout */
  --container-max-width: 1400px;
  --container-padding: 5rem; /* 80px */
  --section-padding-y: 7.5rem; /* 120px */
  
  /* 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;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
}

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

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

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

h1 {
  font-size: var(--text-5xl);
  font-weight: 800;
  letter-spacing: -0.02em;
}

h2 {
  font-size: var(--text-4xl);
  font-weight: 700;
  letter-spacing: -0.01em;
}

h3 {
  font-size: var(--text-3xl);
  font-weight: 700;
}

h4 {
  font-size: var(--text-2xl);
  font-weight: 600;
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-light);
}

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

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Utilities */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section {
  padding: var(--section-padding-y) 0;
}

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

.text-primary {
  color: var(--color-primary);
}

.text-accent {
  color: var(--color-accent);
}

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

.bg-accent {
  background-color: var(--color-accent);
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.875rem 2rem;
  font-family: var(--font-display);
  font-size: var(--text-base);
  font-weight: 600;
  line-height: 1;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  color: white;
}

.btn-accent {
  background: var(--gradient-accent);
  color: white;
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  color: white;
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

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

.btn-large {
  padding: 1.125rem 2.5rem;
  font-size: var(--text-lg);
}

/* Loading State */
.btn-loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}

.btn-loading::after {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  top: 50%;
  left: 50%;
  margin-left: -10px;
  margin-top: -10px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Grid System */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* Cards */
.card {
  background: var(--color-bg-white);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

/* Form Elements */
.form-group {
  margin-bottom: var(--space-5);
}

.form-label {
  display: block;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-2);
  font-size: var(--text-sm);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 0.875rem 1rem;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg-white);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all 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(10, 36, 99, 0.1);
}

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

.form-error {
  color: #EF4444;
  font-size: var(--text-sm);
  margin-top: var(--space-1);
  display: none;
}

.form-input.error,
.form-textarea.error,
.form-select.error {
  border-color: #EF4444;
}

.form-input.error + .form-error,
.form-textarea.error + .form-error,
.form-select.error + .form-error {
  display: block;
}

/* Accessibility */
.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;
}

/* Focus Styles */
*:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}