:root {
  --bg: oklch(0.100 0 0);
  --surface: oklch(0.150 0 0);
  --surface-2: oklch(0.185 0 0);
  --border: oklch(0.280 0.004 200);
  --border-strong: oklch(0.360 0.006 200);
  --ink: oklch(0.950 0.006 200);
  --muted: oklch(0.680 0.012 200);
  --muted-2: oklch(0.520 0.010 200);

  --primary: oklch(0.720 0.110 200);
  --primary-ink: oklch(0.120 0.020 200);
  --primary-dim: oklch(0.720 0.110 200 / 0.14);
  --primary-border: oklch(0.720 0.110 200 / 0.35);

  --accent: oklch(0.870 0.130 70);
  --accent-ink: oklch(0.180 0.030 70);
  --accent-dim: oklch(0.870 0.130 70 / 0.14);

  --danger: oklch(0.640 0.190 25);
  --danger-ink: oklch(0.980 0.010 25);
  --danger-dim: oklch(0.640 0.190 25 / 0.14);
  --danger-border: oklch(0.640 0.190 25 / 0.4);

  --good: oklch(0.700 0.140 150);
  --good-ink: oklch(0.120 0.020 150);
  --good-dim: oklch(0.700 0.140 150 / 0.14);

  --font: -apple-system, "Segoe UI", system-ui, "Inter", sans-serif;
  --mono: ui-monospace, "Cascadia Mono", "Consolas", "SFMono-Regular", Menlo, monospace;

  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;

  --z-sticky: 10;
  --z-toast: 40;

  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--surface);
  color: var(--ink);
  padding: 0.6em 1em;
  z-index: var(--z-toast);
  border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus { left: 0; }

.topbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border);
  background: oklch(0.100 0 0 / 0.85);
  backdrop-filter: blur(10px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
  font-size: 15px;
}

.brand-mark {
  width: 26px;
  height: 26px;
  border-radius: 7px;
  background: var(--primary-dim);
  border: 1px solid var(--primary-border);
  display: grid;
  place-items: center;
  color: var(--primary);
  flex-shrink: 0;
}

.brand-mark svg { width: 15px; height: 15px; }

.topbar-actions a.button-ghost { font-size: 13px; }

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 48px 24px 96px;
}

.page-header {
  margin-bottom: 32px;
}

.page-header h1 {
  font-size: 1.7rem;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
  text-wrap: balance;
}

.page-header p {
  color: var(--muted);
  margin: 0;
  max-width: 62ch;
}

/* Upload form */

.upload-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.dropzone {
  display: block;
  position: relative;
  border: 1.5px dashed var(--border-strong);
  border-radius: var(--radius);
  padding: 40px 24px;
  text-align: center;
  transition: border-color 180ms ease-out, background-color 180ms ease-out;
  cursor: pointer;
}

.dropzone:hover { border-color: var(--muted-2); }

.dropzone.is-dragover,
.dropzone:focus-within {
  border-color: var(--primary);
  background: var(--primary-dim);
}

.dropzone input[type="file"] {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
  width: 100%;
  height: 100%;
}

.dropzone-icon {
  width: 40px;
  height: 40px;
  margin: 0 auto 14px;
  color: var(--muted);
  display: grid;
  place-items: center;
}

.dropzone-icon svg { width: 100%; height: 100%; }

.dropzone-title {
  font-weight: 600;
  margin-bottom: 4px;
}

.dropzone-hint {
  color: var(--muted);
  font-size: 13px;
}

.dropzone-filename {
  margin-top: 14px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--primary);
  display: none;
}

.dropzone.has-file .dropzone-filename { display: block; }

.form-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-top: 20px;
}

.form-note {
  color: var(--muted-2);
  font-size: 12.5px;
  margin: 0;
}

.button {
  appearance: none;
  border: none;
  border-radius: var(--radius-sm);
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: transform 120ms ease-out, background-color 150ms ease-out, opacity 150ms ease-out;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}

.button:active { transform: translateY(1px); }
.button:disabled { opacity: 0.55; cursor: not-allowed; transform: none; }

.button-primary {
  background: var(--primary);
  color: var(--primary-ink);
}
.button-primary:hover:not(:disabled) { background: oklch(0.760 0.110 200); }

.button-ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--border-strong);
}
.button-ghost:hover { background: var(--surface-2); }

.spinner {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid oklch(0.120 0.020 200 / 0.35);
  border-top-color: var(--primary-ink);
  animation: spin 0.7s linear infinite;
  display: none;
}

.button[data-loading="true"] .spinner { display: inline-block; }
.button[data-loading="true"] .button-label { opacity: 0.8; }

@keyframes spin { to { transform: rotate(360deg); } }

.about-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-top: 28px;
  padding: 0;
  list-style: none;
}

.about-list li {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  font-size: 13px;
  color: var(--muted);
}

.about-list strong {
  display: block;
  color: var(--ink);
  font-size: 13.5px;
  margin-bottom: 3px;
}

/* Alerts */

.alert {
  border-radius: var(--radius);
  padding: 14px 16px;
  font-size: 13.5px;
  border: 1px solid var(--border);
  margin-bottom: 20px;
}

.alert-danger {
  background: var(--danger-dim);
  border-color: var(--danger-border);
  color: oklch(0.900 0.040 25);
}

.alert-warn {
  background: var(--accent-dim);
  border-color: oklch(0.870 0.130 70 / 0.4);
  color: oklch(0.900 0.060 70);
}

/* Results: hero */

.hero {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--surface);
  padding: 28px;
  margin-bottom: 24px;
}

.hero-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 11px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.badge-high { background: var(--danger-dim); color: oklch(0.870 0.150 25); }
.badge-warn { background: var(--accent-dim); color: var(--accent); }
.badge-info { background: var(--primary-dim); color: var(--primary); }

.hero h2 {
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  margin: 14px 0 6px;
  text-wrap: balance;
}

.hero-signature {
  font-family: var(--mono);
  font-size: 13.5px;
  color: var(--muted);
  word-break: break-all;
}

.hero-signature .sig-value { color: var(--ink); }

.case-history-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  padding: 8px 14px;
  border-radius: var(--radius);
  background: var(--surface-2);
  border: 1px solid var(--border);
  font-size: 13px;
  color: var(--muted);
}

.case-history-chip strong { color: var(--ink); }

/* Section cards */

.section {
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  padding: 24px 26px;
  margin-bottom: 20px;
}

.section h3 {
  font-size: 1rem;
  margin: 0 0 14px;
  letter-spacing: -0.005em;
}

.section p.narrative {
  margin: 0 0 16px;
  max-width: 70ch;
  color: var(--ink);
}

.evidence-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.evidence-list li {
  display: flex;
  gap: 10px;
  font-size: 13.5px;
  color: var(--muted);
  align-items: flex-start;
}

.evidence-list li svg {
  flex-shrink: 0;
  margin-top: 3px;
  width: 13px;
  height: 13px;
  color: var(--primary);
}

.steps-list {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: step;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.step-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface-2);
}

.step-num {
  counter-increment: step;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--primary-dim);
  color: var(--primary);
  font-size: 12px;
  font-weight: 700;
  display: grid;
  place-items: center;
  flex-shrink: 0;
  margin-top: 1px;
}

.step-num::before { content: counter(step); }

.step-body { flex: 1; }
.step-text { font-size: 13.5px; margin-bottom: 6px; }

.confidence {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 2px 8px;
  border-radius: 999px;
  display: inline-block;
}

.confidence-high { background: var(--primary-dim); color: var(--primary); }
.confidence-medium { background: var(--accent-dim); color: var(--accent); }
.confidence-low { background: var(--surface); color: var(--muted-2); border: 1px solid var(--border); }

/* Technical details */

details.tech {
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  margin-bottom: 20px;
  overflow: hidden;
}

details.tech summary {
  padding: 18px 26px;
  cursor: pointer;
  font-weight: 600;
  font-size: 14px;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

details.tech summary::-webkit-details-marker { display: none; }

.summary-chevron {
  width: 16px;
  height: 16px;
  color: var(--muted);
  transition: transform 180ms ease-out;
  flex-shrink: 0;
}

details.tech[open] .summary-chevron { transform: rotate(90deg); }

.tech-body {
  padding: 4px 26px 24px;
  border-top: 1px solid var(--border);
}

.kv-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px 24px;
  margin-top: 18px;
}

.kv-grid dt {
  font-size: 11.5px;
  color: var(--muted-2);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 3px;
}

.kv-grid dd {
  margin: 0;
  font-family: var(--mono);
  font-size: 13.5px;
  color: var(--ink);
  word-break: break-word;
}

table.data-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 16px;
  font-size: 13px;
}

table.data-table th {
  text-align: left;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted-2);
  font-weight: 600;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border-strong);
}

table.data-table td {
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  font-family: var(--mono);
  color: var(--muted);
}

table.data-table tr:last-child td { border-bottom: none; }

table.data-table td.highlight { color: var(--ink); font-weight: 600; }

.table-scroll {
  overflow-x: auto;
  margin: 0 -2px;
}

.log-tail {
  margin-top: 18px;
  max-height: 340px;
  overflow-y: auto;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.65;
  color: var(--muted);
}

.log-tail .line-flag { color: var(--accent); }
.log-tail .line-error { color: oklch(0.800 0.130 25); }
.log-tail div { white-space: pre-wrap; word-break: break-word; }

.gap-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.gap-list li {
  font-size: 12.5px;
  color: var(--muted-2);
  padding-left: 16px;
  position: relative;
}

.gap-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--muted-2);
}

.result-actions {
  display: flex;
  justify-content: center;
  margin-top: 32px;
}

footer.site-footer {
  text-align: center;
  padding: 32px 24px 48px;
  color: var(--muted-2);
  font-size: 12px;
}

@media (prefers-reduced-motion: reduce) {
  .dropzone, .button, .summary-chevron, .spinner {
    transition: none !important;
    animation: none !important;
  }
}

@media (max-width: 560px) {
  main { padding: 32px 16px 64px; }
  .section, .upload-card { padding: 20px; }
  .tech-body { padding: 4px 18px 20px; }
  details.tech summary { padding: 16px 18px; }
  .form-footer { flex-direction: column; align-items: stretch; }
  .form-footer .button { justify-content: center; }
}