/* Katherine Cass Personal Site - Modern CSS
   Clean, minimal design with Libre Baskerville typography
   Black on white with multicolor hover accents
*/

/* CSS Custom Properties */
:root {
  --color-text: #333;
  --color-text-light: #666;
  --color-background: #fff;
  --color-link: #333;
  --color-accent-blue: #0066cc;
  --color-accent-green: #228b22;
  --color-accent-yellow: #daa520;
  --font-main: 'Libre Baskerville', Georgia, 'Times New Roman', serif;
  --max-width: 900px;
  --spacing-unit: 1rem;
}

/* Reset and Base */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  font-size: 18px;
  line-height: 1.6;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-main);
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.3;
  margin-top: 0;
  margin-bottom: var(--spacing-unit);
}

h1 {
  font-size: 2rem;
}

h2 {
  font-size: 1.5rem;
}

p {
  margin-top: 0;
  margin-bottom: var(--spacing-unit);
}

a {
  color: var(--color-link);
  text-decoration: underline;
  transition: color 0.2s ease;
}

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

/* Navigation */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: var(--color-background);
  z-index: 100;
  padding: var(--spacing-unit) 0;
  transition: transform 0.3s ease;
}

.nav-hidden {
  transform: translateY(-100%);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-unit);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 700;
  text-decoration: none;
  animation: color-cycle 12s ease-in-out infinite;
}

@keyframes color-cycle {
  0%, 100% { color: var(--color-accent-blue); }
  33% { color: var(--color-accent-green); }
  66% { color: var(--color-accent-yellow); }
}

.nav-brand:hover {
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  text-decoration: none;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text);
  transition: color 0.2s ease;
}

/* Multicolor hover accents */
.nav-links a.nav-who:hover,
.nav-links a.nav-who:focus,
.nav-links a.nav-who.active {
  color: var(--color-accent-blue);
}

.nav-links a.nav-what:hover,
.nav-links a.nav-what:focus,
.nav-links a.nav-what.active,
.nav-links a.nav-writings:hover,
.nav-links a.nav-writings:focus,
.nav-links a.nav-writings.active {
  color: var(--color-accent-green);
}

.nav-links a.nav-why:hover,
.nav-links a.nav-why:focus,
.nav-links a.nav-why.active {
  color: var(--color-accent-yellow);
}

/* Bold active nav link */
.nav-links a.active {
  font-weight: 700;
}

/* Color utility classes */
.color-blue { color: var(--color-accent-blue); }
.color-green { color: var(--color-accent-green); }
.color-yellow { color: var(--color-accent-yellow); }

/* Page header colors */
.page-header-blue h1 { color: var(--color-accent-blue); }
.page-header-green h1 { color: var(--color-accent-green); }
.page-header-yellow h1 { color: var(--color-accent-yellow); }

/* Mobile Navigation */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  margin: 5px 0;
  transition: transform 0.3s ease;
}

@media (max-width: 600px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-background);
    flex-direction: column;
    padding: var(--spacing-unit);
    gap: var(--spacing-unit);
    border-bottom: 1px solid #eee;
  }

  .nav-links.active {
    display: flex;
  }
}

/* Main Content */
.main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: calc(4rem + var(--spacing-unit)) var(--spacing-unit) var(--spacing-unit);
  min-height: 100vh;
}

/* Homepage Hero */
.hero {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 60vh;
  text-align: center;
  padding: 2rem 0;
}

.hero-quote {
  font-size: 1.5rem;
  font-style: italic;
  max-width: 700px;
  margin-bottom: 1rem;
  animation: color-cycle 12s ease-in-out infinite;
}

.hero-attribution {
  font-size: 1rem;
  color: var(--color-text-light);
}

@media (min-width: 600px) {
  .hero-quote {
    font-size: 1.75rem;
  }
}

/* Page Headers */
.page-header {
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid #eee;
}

.page-header h1 {
  margin-bottom: 0.5rem;
}

.page-header-links {
  font-size: 0.9rem;
  color: var(--color-text-light);
}

.page-header-links a {
  color: var(--color-text-light);
}

/* Content Grid for two-column layouts */
.content-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 700px) {
  .content-grid {
    grid-template-columns: 1fr 1fr;
  }
}

/* Timeline */
.timeline {
  padding: 0;
  margin: 0;
}

.timeline-item {
  margin-bottom: 1.5rem;
}

.timeline-date {
  font-weight: 700;
  display: block;
  margin-bottom: 0.25rem;
}

.timeline-content {
  color: var(--color-text);
}

/* Social Links */
.social-links {
  list-style: none;
  padding: 0;
  margin: 0;
}

.social-links li {
  margin-bottom: 0.5rem;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

/* Full-width section (spans grid columns) */
.full-width-section {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid #eee;
}

/* LinkedIn Feed Section */
.linkedin-feed {
  margin-top: 2rem;
}

.linkedin-embed {
  border: 1px solid #eee;
  border-radius: 4px;
  overflow: hidden;
}

/* Footer */
.footer {
  text-align: center;
  padding: 2rem var(--spacing-unit);
  color: var(--color-text-light);
  font-size: 0.85rem;
  border-top: 1px solid #eee;
  margin-top: 3rem;
}

/* Utility Classes */
.text-center {
  text-align: center;
}

.text-muted {
  color: var(--color-text-light);
}

/* 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: 0;
}

/* Focus styles for keyboard navigation only (not mouse clicks) */
a:focus,
button:focus {
  outline: none;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent-blue);
  outline-offset: 2px;
}

/* Skip link for accessibility - hidden until focused */
.skip-link {
  position: absolute;
  top: -100px;
  left: 0;
  background: var(--color-text);
  color: var(--color-background);
  padding: 8px;
  z-index: 200;
  text-decoration: none;
  opacity: 0;
}

.skip-link:focus {
  top: 0;
  opacity: 1;
}