/* Base layout ------------------------------------------------------- */
:root {
  color-scheme: light;
  --border: #d1d5db;
  --text: #1f2937;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  color: var(--text);
  background: #f9fafb;
}
.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1rem;
  background: #111827;
  color: #fff;
}
.app-nav a { color: #fff; margin-right: 1rem; text-decoration: none; }
.app-nav a:hover, .app-nav a:focus { text-decoration: underline; }
.app-session { display: flex; align-items: center; gap: 0.5rem; }
.app-session a { color: #fff; }
.app-main { padding: 1rem; max-width: 960px; margin: 0 auto; }

.login-form, .zone-controls { display: flex; flex-direction: column; gap: 0.5rem; max-width: 320px; }
.zone-controls { flex-direction: row; align-items: end; flex-wrap: wrap; max-width: none; }
.zone-controls label { display: flex; flex-direction: column; font-size: 0.85rem; }
.form-error { color: #991b1b; }

#zone-canvas {
  border: 1px solid var(--border);
  background: #111827 center / contain no-repeat;
  cursor: crosshair;
  max-width: 100%;
}

button {
  cursor: pointer;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: #fff;
}
button:hover { background: #f3f4f6; }

/* Event list ---------------------------------------------------------- */
.event-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  margin-bottom: 0.5rem;
  background: #fff;
}
.event-row.is-unacknowledged { border-left: 4px solid #4b5563; }
.event-meta { flex: 1; }
.event-meta .event-type { font-weight: 600; }
.event-meta .event-time { color: #4b5563; font-size: 0.85rem; }

/* Severity badges (NF9): color-blind-safe — icon + text label + color.
   Never rely on color alone. Pastel background + dark text pairs are
   chosen for WCAG-AA contrast (>= 4.5:1 for normal-size text). */
.severity-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.85rem;
  white-space: nowrap;
}
.severity-badge .icon { font-size: 1rem; line-height: 1; }

.sev-critical { background: #fee2e2; color: #991b1b; border: 1px solid #991b1b; }
.sev-high     { background: #ffedd5; color: #9a3412; border: 1px solid #9a3412; }
.sev-warning  { background: #fef9c3; color: #854d0e; border: 1px solid #854d0e; }
.sev-info     { background: #e5e7eb; color: #374151; border: 1px solid #374151; }

.ack-btn { margin-left: auto; }
.ack-btn:disabled { opacity: 0.6; cursor: default; }