:root {
  --color-blue: #0066aa;
  --color-yellow: #ffd557;
  --color-white: #ffffff;
  --color-text: #333333;
  --gradient-header: linear-gradient(135deg, #eff1f3 0%, #dcdce0 100%);
  --max-width: 1200px;
  --font-primary: "DM Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
  --font-serif: "Source Serif Pro", Georgia, serif;
}

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

body {
  font-family: var(--font-primary);
  color: var(--color-text);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a,
button {
  transition: color 0.2s, background-color 0.2s;
}

img {
  max-width: 100%;
  height: auto;
  vertical-align: bottom;
}

/* Header */

.header {
  background: var(--gradient-header);
  text-align: center;
  padding-top: 1rem;
}

.header-logo {
  display: block;
  margin: 0 auto;
}

.header-logo img {
  width: 90px;
  height: 90px;
}

.header h1 {
  color: var(--color-blue);
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: 2px;
  line-height: 1;
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
  margin: 0;
}

.header h1 a {
  color: var(--color-blue);
  text-decoration: none;
}

/* Navigation */

.nav {
  background-color: var(--color-blue);
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-white);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.5rem 1rem;
}

.nav-list {
  list-style: none;
  display: flex;
  gap: 0;
  justify-content: center;
  flex-wrap: wrap;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 0.75rem 1rem;
  color: var(--color-white);
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  text-transform: capitalize;
  white-space: nowrap;
  transition: box-shadow 0.2s;
}

.nav-link:hover,
.nav-link[aria-current="page"] {
  text-decoration: none;
  box-shadow: inset 0 -3px 0 var(--color-yellow);
}

.nav-dropdown {
  position: absolute;
  top: 100%;
  left: 0;
  background-color: var(--color-blue);
  min-width: 200px;
  display: none;
  z-index: 100;
  list-style: none;
  padding: 0;
}

.nav-item:hover .nav-dropdown,
.nav-item:focus-within .nav-dropdown {
  display: block;
}

.nav-dropdown .nav-link {
  padding: 0.5rem 1rem;
  white-space: nowrap;
}

/* Main content */

main {
  max-width: var(--max-width);
  margin: 2rem auto;
  padding: 0 1.5rem;
}

.content h1 {
  font-weight: 400;
  font-size: 2rem;
  margin-top: 1.25rem;
  margin-bottom: 1.25rem;
}

.content h2 {
  font-weight: 600;
  font-size: 1.5rem;
  margin-top: 1.5rem;
  margin-bottom: 0.75rem;
}

.content p {
  margin-bottom: 1rem;
}

.content p:last-child {
  margin-bottom: 0;
}

.content ul,
.content ol {
  margin-bottom: 1rem;
  padding-left: 2rem;
}

.content li {
  margin-bottom: 0.25rem;
}

.content em {
  font-style: italic;
}

.content strong {
  font-weight: 700;
}

.content a {
  color: var(--color-blue);
}

.content blockquote {
  border-left: 4px solid var(--color-blue);
  margin: 1rem 0;
  padding: 0.5rem 1rem;
  color: #555;
  font-style: italic;
}

.content hr {
  border: none;
  border-top: 1px solid #ddd;
  margin: 1.5rem 0;
}

.content code {
  background-color: #f5f5f5;
  padding: 0.15rem 0.3rem;
  border-radius: 3px;
  font-size: 0.9em;
}

/* Homepage sidebar nav */

.sidebar-nav {
  font-size: 0.875rem;
  line-height: 1.8;
  margin-bottom: 1rem;
}

.sidebar-nav a {
  text-decoration: underline;
  display: inline-block;
  padding: 0.15rem 0;
}

/* Photo columns */

.photo-columns {
  display: flex;
  gap: 2rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 1rem 0;
}

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

.photo-column img {
  border-radius: 4px;
}

.photo-column figcaption {
  margin-top: 0.5rem;
  font-size: 0.9rem;
}

/* Callout banner */

.callout-banner {
  text-align: center;
  color: var(--color-blue);
  background-color: var(--color-yellow);
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-style: italic;
  font-weight: 600;
  padding: 1.25rem 2.375rem;
  margin: 1rem 0;
}

/* Tables */

.content table {
  border-collapse: collapse;
  width: 100%;
  margin-bottom: 1rem;
}

.content th,
.content td {
  padding: 0.5rem;
  border: 1px solid #ddd;
  text-align: left;
}

.content th {
  font-weight: 700;
  background-color: #f5f5f5;
}

.content figure {
  margin-bottom: 1rem;
}

.content figcaption {
  font-size: 0.875rem;
  color: #666;
  margin-top: 0.5rem;
}

/* Footer */

.footer {
  background-color: var(--color-blue);
  color: var(--color-white);
  padding: 1.5rem;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer a {
  color: var(--color-white);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

.footer-site-title {
  font-weight: normal;
  font-size: 1rem;
  line-height: 1.4;
}

/* Focus */

:focus-visible {
  outline: 2px solid var(--color-yellow);
  outline-offset: 2px;
}

/* Responsive */

@media (max-width: 768px) {
  .nav {
    justify-content: flex-start;
    position: relative;
  }

  .nav-toggle {
    display: block;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    width: 100%;
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--color-blue);
    z-index: 200;
  }

  .nav[data-nav-open="true"] .nav-list {
    display: flex;
  }

  .nav-item {
    width: 100%;
  }

  .nav-dropdown {
    position: static;
    display: none;
  }

  .nav-item:hover .nav-dropdown,
  .nav-item:focus-within .nav-dropdown {
    display: block;
  }

  .nav-dropdown .nav-link {
    padding-left: 2rem;
  }

  .header h1 {
    font-size: 1.25rem;
  }

  .photo-columns {
    flex-direction: column;
    align-items: center;
  }

  .content h1 {
    font-size: 1.5rem;
  }

  .content table {
    display: block;
    overflow-x: auto;
  }

  main {
    margin: 1rem auto;
    padding: 0 1rem;
  }
}

/* Print */

@media print {
  .nav,
  .nav-toggle,
  .footer,
  .sidebar-nav {
    display: none !important;
  }

  main {
    margin: 0;
    padding: 0;
  }

  .header {
    background: none;
  }

  a {
    text-decoration: underline;
  }
}