/* SelfDataGuard demo — minimal sober dark theme */
* { box-sizing: border-box; }
html { font-size: 16px; }
body {
  margin: 0;
  padding: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: #0F172A;
  color: #E2E8F0;
  line-height: 1.5;
}
header {
  padding: 2rem 1.5rem 1.5rem;
  border-bottom: 1px solid #1E293B;
  background: linear-gradient(180deg, #0F172A 0%, #1E293B 100%);
}
header h1 {
  margin: 0 0 0.25rem;
  font-size: 2rem;
  font-weight: 700;
  color: #3B82F6;
}
header h1 .version {
  font-size: 0.85rem;
  font-weight: 400;
  color: #64748B;
  margin-left: 0.5rem;
  letter-spacing: 0.05em;
}
header .tagline {
  margin: 0 0 0.75rem;
  font-style: italic;
  color: #94A3B8;
}
header nav {
  font-size: 0.85rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
}
header nav a {
  color: #60A5FA;
  text-decoration: none;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  border: 1px solid transparent;
  transition: all 0.15s;
}
header nav a:hover {
  background: rgba(59, 130, 246, 0.12);
  border-color: rgba(59, 130, 246, 0.3);
  text-decoration: none;
}
header nav a.nav-cta {
  background: #3B82F6;
  color: #FFF;
  font-weight: 600;
  border-color: #2563EB;
}
header nav a.nav-cta:hover {
  background: #2563EB;
  border-color: #1E40AF;
}
header nav .nav-license {
  color: #64748B;
  font-size: 0.75rem;
  margin-left: auto;
  letter-spacing: 0.05em;
}

#explainer {
  max-width: 1400px;
  margin: 1.5rem auto 0;
  padding: 0 1.5rem;
}
#explainer h2 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
  color: #93C5FD;
}
#explainer p {
  margin: 0;
  font-size: 0.9rem;
  color: #CBD5E1;
}

main {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1.5rem;
}
main.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 1.5rem;
  align-items: start;
}
@media (max-width: 980px) {
  main.split { grid-template-columns: 1fr; }
}
.col-frontend, .col-backend {
  min-width: 0;
}
.col-backend {
  position: sticky;
  top: 1rem;
  max-height: calc(100vh - 2rem);
  overflow: auto;
}
.col-title {
  margin: 0 0 1rem;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #64748B;
  border-bottom: 1px solid #334155;
  padding-bottom: 0.5rem;
}
.col-backend .col-title {
  color: #FBBF24;
}
.col-backend .result {
  max-height: calc(100vh - 14rem);
}
section {
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: #1E293B;
  border: 1px solid #334155;
  border-radius: 8px;
}
section h2 {
  margin-top: 0;
  margin-bottom: 1rem;
  font-size: 1.2rem;
  color: #93C5FD;
  font-weight: 600;
}
section p {
  margin: 0 0 1rem;
  color: #CBD5E1;
}
section p.hint {
  font-size: 0.85rem;
  color: #94A3B8;
  background: #0F172A;
  border-left: 3px solid #3B82F6;
  padding: 0.6rem 0.8rem;
  margin: 0 0 1rem;
  border-radius: 0 4px 4px 0;
}
section p.hint strong { color: #93C5FD; }
form {
  display: grid;
  gap: 0.6rem;
}
label {
  display: grid;
  gap: 0.25rem;
  font-size: 0.85rem;
  color: #94A3B8;
}
input, select {
  background: #0F172A;
  color: #E2E8F0;
  border: 1px solid #334155;
  border-radius: 4px;
  padding: 0.5rem 0.6rem;
  font-size: 0.9rem;
  font-family: ui-monospace, monospace;
}
input:focus, select:focus {
  outline: none;
  border-color: #3B82F6;
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}
fieldset {
  border: 1px solid #334155;
  border-radius: 4px;
  padding: 0.75rem;
  display: grid;
  gap: 0.5rem;
}
fieldset legend {
  padding: 0 0.5rem;
  color: #93C5FD;
  font-size: 0.85rem;
  font-weight: 600;
}
button {
  background: #3B82F6;
  color: white;
  border: none;
  border-radius: 4px;
  padding: 0.6rem 1rem;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 0.5rem;
  justify-self: start;
}
button:hover { background: #2563EB; }
button.danger { background: #DC2626; }
button.danger:hover { background: #B91C1C; }
button:disabled {
  background: #475569;
  cursor: not-allowed;
}
.result {
  margin-top: 1rem;
  padding: 0.75rem;
  background: #0F172A;
  border: 1px solid #1E293B;
  border-radius: 4px;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
  font-size: 0.8rem;
  color: #94A3B8;
  white-space: pre-wrap;
  word-break: break-all;
  max-height: 30rem;
  overflow: auto;
}
.result.ok { color: #6EE7B7; border-color: #064E3B; }
.result.err { color: #FCA5A5; border-color: #7F1D1D; }
footer {
  text-align: center;
  padding: 1.5rem;
  font-size: 0.8rem;
  color: #64748B;
  border-top: 1px solid #1E293B;
}
footer a { color: #60A5FA; }
footer p { margin: 0.25rem 0; }
footer .footer-notice {
  font-size: 0.75rem;
  color: #475569;
  font-style: italic;
}
footer .footer-notice strong {
  color: #94A3B8;
  font-style: normal;
}