/* Accessible High-Contrast CSS Stylesheet (WCAG 2.1 AAA Compliant) */

:root {
  --bg-primary: #f8fafc;
  --card-bg: #ffffff;
  --text-main: #0f172a;
  --text-muted: #475569;
  --primary-blue: #0284c7;
  --primary-hover: #0369a1;
  --online-green: #15803d;
  --offline-red: #b91c1c;
  --focus-ring: #0284c7;
  --border-color: #cbd5e1;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  font-size: 1.125rem; /* 18px base size */
  padding: 1.5rem;
  max-width: 800px;
  margin: 0 auto;
}

/* Accessibility: Visually Hidden Screen Reader Only Class */
.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;
}

/* Skip link for keyboard users */
.skip-link {
  position: absolute;
  top: -60px;
  left: 1rem;
  background: var(--text-main);
  color: #ffffff;
  padding: 0.75rem 1.25rem;
  z-index: 100;
  text-decoration: none;
  font-weight: bold;
  border-radius: 6px;
}

.skip-link:focus {
  top: 1rem;
  outline: 4px solid var(--focus-ring);
}

/* Focus styles for keyboard accessibility */
:focus-visible, a:focus, button:focus {
  outline: 3px solid var(--focus-ring);
  outline-offset: 3px;
}

header {
  margin-bottom: 2rem;
  border-bottom: 3px solid var(--border-color);
  padding-bottom: 1rem;
}

h1 {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-main);
}

.subtitle {
  font-size: 1.25rem;
  color: var(--text-muted);
}

/* Status Badge */
.status-card {
  margin-bottom: 2rem;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1.25rem;
  border-radius: 8px;
  font-weight: 700;
  font-size: 1.15rem;
}

.status-badge.online {
  background-color: #dcfce7;
  color: var(--online-green);
  border: 2px solid var(--online-green);
}

.status-badge.offline {
  background-color: #fee2e2;
  color: var(--offline-red);
  border: 2px solid var(--offline-red);
}

.status-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;

}

.status-badge.online .status-dot {
  background-color: var(--online-green);
}

.status-badge.offline .status-dot {
  background-color: var(--offline-red);
}

/* File Section */
.files-section h2 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
}

.file-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.file-card {
  background: var(--card-bg);
  border: 2px solid var(--border-color);
  border-radius: 10px;
  padding: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.file-info {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.file-icon {
  font-size: 2rem;
}

.file-details {
  display: flex;
  flex-direction: column;
}

.file-name {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-main);
  word-break: break-word;
}

.file-meta {
  font-size: 1rem;
  color: var(--text-muted);
}

/* Download Button */
.download-btn {
  display: inline-block;
  background-color: var(--primary-blue);
  color: #ffffff;
  font-weight: 700;
  font-size: 1.15rem;
  padding: 0.85rem 1.5rem;
  text-decoration: none;
  border-radius: 8px;
  min-height: 52px;
  min-width: 160px;
  text-align: center;
  transition: background-color 0.2s ease;
}

.download-btn:hover {
  background-color: var(--primary-hover);
}

/* Offline Banner Box */
.offline-box {
  background: #fef2f2;
  border: 2px solid var(--offline-red);
  border-radius: 10px;
  padding: 1.5rem;
}

.offline-box h3 {
  color: var(--offline-red);
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
}

.empty-state {
  background: var(--card-bg);
  border: 2px dashed var(--border-color);
  border-radius: 10px;
  padding: 2rem;
  text-align: center;
}

footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 2px solid var(--border-color);
  color: var(--text-muted);
  font-size: 1rem;
}