/* ============================================
   SUPPLY CHAIN ANALYTICS - BASE STYLES
   Data2Value Initiative
   ============================================ */

/* CSS Reset & Box Sizing */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* Root Variables - Shared Across Themes */
:root {
  /* Typography Scale */
  --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;
  
  /* Spacing Scale */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;
}

/* Base HTML & Body */
html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body, system-ui, sans-serif);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text, #333);
  background-color: var(--color-bg, #fff);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

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

/* Links */
a {
  color: var(--color-primary, #0066ff);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-dark, #0052cc);
  text-decoration: underline;
}

/* Lists */
ul, ol {
  padding-left: var(--space-6);
  margin-bottom: var(--space-4);
}

li {
  margin-bottom: var(--space-2);
}

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--space-6);
}

th, td {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--color-border, #e0e0e0);
}

th {
  font-weight: 600;
  background-color: var(--color-bg-alt, #f5f5f5);
}

/* Code */
code {
  font-family: 'Fira Code', 'Monaco', monospace;
  font-size: 0.9em;
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-bg-alt, #f5f5f5);
  border-radius: var(--radius-sm);
}

pre {
  background-color: var(--color-bg-alt, #1e1e1e);
  color: var(--color-code-text, #f8f8f2);
  padding: var(--space-4);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--space-6);
}

pre code {
  background: none;
  padding: 0;
}

/* ============================================
   PRESENTATION FRAMEWORK
   ============================================ */

/* Slide Container */
.presentation {
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  position: relative;
}

.slide {
  width: 100%;
  height: 100%;
  padding: var(--space-12);
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

.slide.active {
  opacity: 1;
  visibility: visible;
}

/* Slide Layouts */
.slide--title {
  text-align: center;
  justify-content: center;
  align-items: center;
}

.slide--content {
  justify-content: flex-start;
  padding-top: var(--space-20);
}

.slide--split {
  flex-direction: row;
  gap: var(--space-12);
}

.slide--split > * {
  flex: 1;
}

/* Navigation */
.nav-controls {
  position: fixed;
  bottom: var(--space-8);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: var(--space-4);
  z-index: 100;
}

.nav-btn {
  padding: var(--space-3) var(--space-6);
  background-color: var(--color-primary, #0066ff);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-sm);
  transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.nav-btn:hover {
  background-color: var(--color-primary-dark, #0052cc);
  transform: scale(1.05);
}

.nav-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Progress Bar */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  background-color: var(--color-primary, #0066ff);
  transition: width var(--transition-base);
  z-index: 100;
}

/* Slide Counter */
.slide-counter {
  position: fixed;
  bottom: var(--space-4);
  right: var(--space-4);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted, #666);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

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

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.gap-4 { gap: var(--space-4); }
.gap-8 { gap: var(--space-8); }

.mt-4 { margin-top: var(--space-4); }
.mt-8 { margin-top: var(--space-8); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-8 { margin-bottom: var(--space-8); }

.hidden { display: none; }
.visible { visibility: visible; }

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

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-50px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInRight {
  from { opacity: 0; transform: translateX(50px); }
  to { opacity: 1; transform: translateX(0); }
}

.animate-fadeIn { animation: fadeIn 0.6s ease forwards; }
.animate-slideInLeft { animation: slideInLeft 0.6s ease forwards; }
.animate-slideInRight { animation: slideInRight 0.6s ease forwards; }

.delay-100 { animation-delay: 100ms; }
.delay-200 { animation-delay: 200ms; }
.delay-300 { animation-delay: 300ms; }
.delay-400 { animation-delay: 400ms; }
.delay-500 { animation-delay: 500ms; }

/* Responsive */
@media (max-width: 768px) {
  .slide {
    padding: var(--space-6);
  }
  
  .slide--split {
    flex-direction: column;
  }
  
  h1 { font-size: var(--font-size-3xl); }
  h2 { font-size: var(--font-size-2xl); }
}