:root {
  --bg-color: #ffffff;
  --text-color: #212121;
  --link-color: #005a9c;
  --focus-outline: 3px solid #000000;
  --focus-bg: #ffeb3b;
  --focus-text: #000000;
  --table-border: #555;
  --table-header-bg: #f0f0f0;
}

body {
  font-family: sans-serif; /* Keep it simple and legible */
  line-height: 1.6;
  color: var(--text-color);
  background-color: var(--bg-color);
  margin: 0;
  padding: 0;
}

/* Skip Link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--focus-bg);
  color: var(--focus-text);
  padding: 8px;
  z-index: 100;
  text-decoration: none;
  font-weight: bold;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 0;
  outline: var(--focus-outline);
}

/* Layout */
header, nav, main, footer {
  padding: 1rem;
  max-width: 800px;
  margin: 0 auto;
}

header {
  border-bottom: 2px solid var(--text-color);
  margin-bottom: 1rem;
}

/* Navigation */
nav ul {
  list-style: none;
  padding: 0;
}

nav li {
  margin-bottom: 0.5rem;
}

a {
  color: var(--link-color);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

a:hover {
  text-decoration: none;
  background-color: #eef;
}

a:focus {
  outline: var(--focus-outline);
  background-color: var(--focus-bg);
  color: var(--focus-text);
  box-shadow: 0 0 5px rgba(0,0,0,0.5);
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
  margin-top: 1.5rem;
  margin-bottom: 1rem;
}

/* Tables - Accessible Styling */
.table-container {
  overflow-x: auto;
}

.table-container:focus {
  outline: var(--focus-outline);
  box-shadow: 0 0 5px rgba(0,0,0,0.5);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
}

caption {
  font-weight: bold;
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  text-align: left;
}

th, td {
  border: 1px solid var(--table-border);
  padding: 0.75rem;
  text-align: left;
  vertical-align: top;
}

th {
  background-color: var(--table-header-bg);
  font-weight: bold;
}

/* Mobile Responsiveness */
@media (max-width: 600px) {
  header, nav, main, footer {
    padding: 0.5rem;
  }
}