/* USC Immersion Day - Enhanced CSS Styling System */

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

/* Typography and Color Scheme */
:root {
  /* Professional color scheme */
  --primary-blue: #232f3e;
  --amazon-blue: #232f3e;
  --usc-cardinal: #990000;
  --text-primary: #232f3e;
  --text-secondary: #666666;
  --background-white: #ffffff;
  --background-light: #f8f9fa;
  --border-light: #e9ecef;
  --link-blue: #0066cc;
  --link-hover: #004499;
  --success-green: #28a745;
  
  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-size-base: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 24px;
  --font-size-xxl: 32px;
  --line-height-base: 1.6;
  --line-height-heading: 1.3;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* Border radius */
  --border-radius: 8px;
  --border-radius-lg: 12px;
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.12);
}

/* Base HTML Elements */
html {
  font-size: var(--font-size-base);
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  line-height: var(--line-height-base);
  color: var(--text-primary);
  background-color: var(--background-light);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Main Content Container */
.content {
  max-width: 800px;
  margin: 0 auto;
  background: var(--background-white);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

/* Header Section with Images */
.header-section {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-lg);
  border-bottom: 2px solid var(--border-light);
}

.header-images {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-lg);
  flex-wrap: wrap;
  margin-bottom: var(--spacing-md);
}

.header-images img {
  max-width: 100%;
  height: auto;
  border-radius: var(--border-radius);
}

.aws-logo {
  max-height: 180px;
}

.usc-logo {
  max-height: 140px;
}

/* Typography Hierarchy */
h1 {
  font-size: var(--font-size-xxl);
  font-weight: 700;
  color: var(--primary-blue);
  line-height: var(--line-height-heading);
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--primary-blue);
  line-height: var(--line-height-heading);
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-xs);
  border-bottom: 2px solid var(--amazon-blue);
}

h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-sm);
}

p {
  margin-bottom: var(--spacing-sm);
  color: var(--text-secondary);
}

/* Navigation Bar */
.nav-bar {
  display: flex;
  justify-content: center;
  gap: var(--spacing-md);
  padding: var(--spacing-lg) 0;
  margin-bottom: var(--spacing-lg);
  background: linear-gradient(135deg, var(--background-light), white);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.nav-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  background: #2c3e50;
  color: white !important;
  text-decoration: none;
  border-radius: var(--border-radius);
  font-weight: 600;
  font-size: 14px;
  transition: all 0.3s ease;
  min-width: 120px;
  text-align: center;
  border: 2px solid #2c3e50;
  box-shadow: var(--shadow-md);
  flex: 1;
  max-width: 250px;
}

.nav-button:hover {
  background: #34495e;
  color: white !important;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  border-color: #34495e;
}

.nav-button:focus {
  outline: 2px solid var(--amazon-blue);
  outline-offset: 2px;
}

.nav-button:active {
  transform: translateY(0);
}

/* Responsive navigation */
@media (max-width: 767px) {
  .nav-bar {
    flex-direction: column;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
  }
  
  .nav-button {
    width: 100%;
    min-width: auto;
    max-width: none;
    font-size: 13px;
    padding: 6px 12px;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .nav-bar {
    gap: var(--spacing-sm);
  }
  
  .nav-button {
    min-width: 120px;
    max-width: 160px;
    font-size: 13px;
    padding: 6px 12px;
  }
}

/* Content Sections */
.section {
  margin-bottom: var(--spacing-xl);
}

.access-section {
  background: linear-gradient(135deg, var(--primary-blue), #3a4a5c);
  color: white;
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  margin-bottom: var(--spacing-xl);
}

.access-section h3 {
  color: white;
  margin-bottom: var(--spacing-md);
}

.access-section p {
  color: rgba(255, 255, 255, 0.9);
}

/* Agenda Styles */
.agenda-container {
  background: var(--background-light);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  border-left: 4px solid var(--amazon-blue);
}

.agenda-item {
  display: flex;
  align-items: flex-start;
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--border-light);
  gap: var(--spacing-md);
}

.agenda-item:last-child {
  border-bottom: none;
}

.agenda-time {
  font-weight: 600;
  color: var(--primary-blue);
  min-width: 140px;
  flex-shrink: 0;
  font-size: 0.95em;
}

.agenda-activity {
  color: var(--text-primary);
  line-height: 1.4;
  flex: 1;
}

/* Responsive agenda layout */
@media (max-width: 767px) {
  .agenda-item {
    flex-direction: column;
    gap: var(--spacing-xs);
  }
  
  .agenda-time {
    min-width: auto;
    font-size: 0.9em;
  }
  
  .agenda-activity {
    padding-left: var(--spacing-sm);
  }
}

/* Link Styles */
a {
  color: var(--link-blue);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
  word-break: break-word;
}

a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

a:focus {
  outline: 2px solid var(--amazon-blue);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Primary Call-to-Action Links */
.cta-link {
  display: inline-block;
  background: var(--amazon-blue);
  color: white !important;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius);
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  margin: var(--spacing-xs) 0;
}

.cta-link:hover {
  background: #1a252f;
  color: white !important;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.cta-link:focus {
  outline: 2px solid var(--amazon-blue);
  outline-offset: 2px;
}

/* Secondary Links */
.secondary-link {
  display: inline-block;
  background: var(--background-light);
  color: var(--text-primary) !important;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 2px solid var(--border-light);
  border-radius: var(--border-radius);
  font-weight: 500;
  text-decoration: none;
  transition: all 0.3s ease;
  margin: var(--spacing-xs) 0;
}

.secondary-link:hover {
  background: white;
  border-color: var(--amazon-blue);
  color: var(--text-primary) !important;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
}

/* Lab Options and Resources Lists */
.link-list {
  list-style: none;
  padding: 0;
}

.link-list li {
  margin-bottom: var(--spacing-sm);
  padding: var(--spacing-sm);
  background: var(--background-light);
  border-radius: var(--border-radius);
  border-left: 4px solid var(--amazon-blue);
  transition: all 0.3s ease;
}

.link-list li:hover {
  background: white;
  box-shadow: var(--shadow-sm);
  transform: translateX(4px);
}

.link-list a {
  font-weight: 500;
  display: block;
}

/* Responsive Design - Mobile First Approach */

/* Mobile devices (default styles above are mobile-first) */
@media (max-width: 767px) {
  .content {
    margin: var(--spacing-sm);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
  }
  
  .header-images {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .aws-logo {
    max-height: 140px;
  }
  
  .usc-logo {
    max-height: 100px;
  }
  
  h1 {
    font-size: var(--font-size-xl);
  }
  
  h2 {
    font-size: var(--font-size-lg);
  }
  
  .access-section {
    padding: var(--spacing-md);
  }
  
  .cta-link,
  .secondary-link {
    display: block;
    text-align: center;
    margin: var(--spacing-sm) 0;
  }
}

/* Tablet devices */
@media (min-width: 768px) and (max-width: 1023px) {
  .content {
    max-width: 720px;
    margin: var(--spacing-lg) auto;
  }
  
  .header-images {
    gap: var(--spacing-lg);
  }
}

/* Desktop devices */
@media (min-width: 1024px) {
  .content {
    max-width: 800px;
    margin: var(--spacing-xl) auto;
  }
  
  .header-images {
    gap: var(--spacing-xl);
  }
  
  /* Two-column layout for larger screens if needed */
  .two-column {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
  }
}

/* Large desktop devices */
@media (min-width: 1200px) {
  .content {
    max-width: 900px;
  }
}

/* Print styles */
@media print {
  body {
    background: white;
    color: black;
  }
  
  .content {
    box-shadow: none;
    margin: 0;
    padding: 0;
  }
  
  .access-section {
    background: white !important;
    color: black !important;
    border: 2px solid black;
  }
  
  .cta-link,
  .secondary-link {
    background: white !important;
    color: black !important;
    border: 1px solid black;
  }
  
  a {
    color: black !important;
    text-decoration: underline;
  }
  
  a[href]:after {
    content: " (" attr(href) ")";
    font-size: 0.8em;
    color: #666;
  }
}

/* Accessibility enhancements */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --text-primary: #000000;
    --text-secondary: #000000;
    --background-white: #ffffff;
    --border-light: #000000;
    --link-blue: #0000ff;
    --link-hover: #000080;
  }
  
  .access-section {
    background: #000000 !important;
    color: #ffffff !important;
    border: 2px solid #ffffff;
  }
}

/* Focus visible for better keyboard navigation */
*:focus-visible {
  outline: 2px solid var(--amazon-blue);
  outline-offset: 2px;
  border-radius: 2px;
}