/* Lab: forward proxy vs. reverse proxy.
   Scoped to this one page. Every class is prefixed .pt- so it cannot collide
   with the site stylesheet or with another lab. Design tokens (--accent,
   --bg-raised, --mono ...) come from /css/style.css.

   Colour meaning throughout: red = the proxy, and whatever it can read;
   green = the far end; muted = the party that does not know what is going
   on. The dashed outline means "unaware" wherever it appears. */

/* ---------- intro ---------- */

.pt-glossary { margin: 10px 0 0; font-size: 0.92rem; }
.pt-glossary dt {
  font-family: var(--mono);
  font-size: 0.88rem;
  color: var(--text);
  margin-top: 10px;
}
.pt-glossary dd { margin: 2px 0 0; color: var(--text-muted); }

/* ---------- controls ---------- */

.pt-controls { margin-top: 32px; }

.pt-control-row {
  display: grid;
  grid-template-columns: 3fr 1fr;
  gap: 14px;
  align-items: end;
}
@media (max-width: 560px) {
  .pt-control-row { grid-template-columns: 1fr; }
}

.pt-control-row input[type="text"],
.pt-control-row select {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.95rem;
  padding: 10px 12px;
}
.pt-control-row input[type="text"]:focus,
.pt-control-row select:focus { outline: none; border-color: var(--accent); }

.pt-presets { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }

.pt-preset {
  background: none;
  border: 1px dashed var(--border);
  border-radius: 999px;
  color: var(--text-muted);
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 4px 12px;
  cursor: pointer;
}
.pt-preset:hover { border-color: var(--accent); border-style: solid; color: var(--accent); }

.pt-modes {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  border: none;
  margin-top: 22px;
}
@media (max-width: 560px) {
  .pt-modes { grid-template-columns: 1fr; }
}
.pt-modes legend { margin-bottom: 8px; }

.pt-mode {
  display: block;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-raised);
  padding: 12px 16px;
  cursor: pointer;
}
.pt-mode:hover { border-color: var(--text-muted); }
.pt-mode input { accent-color: var(--accent); margin-right: 8px; }
.pt-mode-name { font-family: var(--mono); font-size: 0.92rem; font-weight: 700; }
.pt-mode-sub {
  display: block;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 4px;
  padding-left: 24px;
}
.pt-mode:has(input:checked) { border-color: var(--accent); }

.pt-transport { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-top: 18px; }

.pt-step-btn {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-muted);
  font-family: var(--mono);
  font-size: 0.8rem;
  padding: 7px 14px;
  cursor: pointer;
}
.pt-step-btn:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.pt-step-btn:disabled { opacity: 0.4; cursor: default; }

.pt-status {
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 14px;
  min-height: 1.2em;
}
.pt-status-error { color: var(--accent); }

/* ---------- the diagram ---------- */

.pt-diagram {
  background: var(--bg-inset);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 8px 4px;
  margin-top: 30px;
}

.pt-svg { width: 100%; height: auto; display: block; font-family: var(--mono); }

/* trust boundary — the single most important mark on the diagram */
.pt-boundary {
  fill: color-mix(in srgb, var(--accent) 7%, transparent);
  stroke: color-mix(in srgb, var(--accent) 45%, transparent);
  stroke-width: 1;
  stroke-dasharray: 6 5;
}
.pt-boundary-label {
  fill: var(--accent);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* nodes */
.pt-node-box { fill: var(--bg-raised); stroke: var(--border); stroke-width: 1; }
.pt-node-client .pt-node-box { stroke: var(--text-muted); }
.pt-node-proxy .pt-node-box { stroke: var(--accent); stroke-width: 2; }
.pt-node-origin .pt-node-box { stroke: var(--allow); }

/* the dashed outline means the box does not know a proxy is in the path */
.pt-node.pt-unaware .pt-node-box { stroke-dasharray: 5 4; }

.pt-node-label { fill: var(--text); font-size: 14px; }
.pt-node-proxy .pt-node-label { fill: var(--accent); }
.pt-node-origin .pt-node-label { fill: var(--allow); }
.pt-node-sub { fill: var(--text-muted); font-size: 11px; }
.pt-node-aware { fill: var(--text-muted); font-size: 10px; font-style: italic; }
.pt-node.pt-unaware .pt-node-aware { fill: var(--accent); }
.pt-node-owner { fill: var(--text-muted); font-size: 10px; }

/* links */
.pt-link { stroke: var(--border); stroke-width: 2; }
.pt-seg-active .pt-link { stroke: var(--accent); }
.pt-seg-label {
  fill: var(--accent);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* the packet. Both links are the same length in viewBox units (135), so one
   pair of keyframes drives either direction. */
.pt-packet { fill: var(--accent); opacity: 0; }
@keyframes pt-glide {
  from { transform: translateX(0); }
  to { transform: translateX(135px); }
}
@keyframes pt-glide-back {
  from { transform: translateX(135px); }
  to { transform: translateX(0); }
}
.pt-packet-go { opacity: 1; animation: pt-glide 1.3s ease-in-out infinite; }
.pt-packet-back { opacity: 1; animation: pt-glide-back 1.3s ease-in-out infinite; }

/* what the visitor believes, in reverse mode */
.pt-belief-line {
  fill: none;
  stroke: var(--text-muted);
  stroke-width: 1;
  stroke-dasharray: 4 4;
}
.pt-belief-label { fill: var(--text-muted); font-size: 10px; font-style: italic; }

@media (prefers-reduced-motion: reduce) {
  .pt-packet-go, .pt-packet-back { animation: none; opacity: 1; }
}

.pt-diagram-caption {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 10px;
}

/* ---------- steps ---------- */

.pt-steps { margin-top: 12px; }

.pt-step {
  border: 1px solid var(--border);
  border-left: 4px solid var(--border);
  border-radius: 8px;
  background: var(--bg-raised);
  padding: 16px 20px;
  margin: 12px 0;
  cursor: pointer;
  transition: opacity 0.2s ease-out, border-color 0.2s ease-out;
}
.pt-step-clear { border-left-color: var(--accent); }
.pt-step-metadata { border-left-color: #d9a03f; }
.pt-step-opaque { border-left-color: var(--allow); }
.pt-step-none { border-left-color: var(--text-muted); }

/* walkthrough state: the step you are on, the ones behind it, the rest */
.pt-step.pt-todo { opacity: 0.42; }
.pt-step.pt-done { opacity: 0.75; }
.pt-step.pt-active { opacity: 1; border-color: var(--accent); }

@media (prefers-reduced-motion: reduce) {
  .pt-step.pt-todo, .pt-step.pt-done { opacity: 1; }
  .pt-step { transition: none; }
}

.pt-step-head { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

.pt-step-num {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 7px;
}
.pt-step.pt-active .pt-step-num { border-color: var(--accent); color: var(--accent); }
.pt-step-title { font-size: 1rem; margin: 0; }

.pt-badge {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 2px 8px;
  color: var(--text-muted);
  margin-left: auto;
}
.pt-badge-clear { border-color: var(--accent); color: var(--accent); }
.pt-badge-metadata { border-color: #d9a03f; color: #d9a03f; }
.pt-badge-opaque { border-color: var(--allow); color: var(--allow); }

.pt-step-summary { font-size: 0.88rem; margin: 8px 0 0; }

.pt-mini-label {
  display: block;
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin: 14px 0 6px;
}

.pt-wire {
  background: var(--bg-inset);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px 12px;
  font-size: 0.76rem;
  margin: 0;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.pt-sees {
  border: 1px dashed var(--border);
  border-radius: 6px;
  background: var(--bg-inset);
  padding: 4px 14px 12px;
  margin-top: 14px;
}
.pt-sees-proxy { border-color: color-mix(in srgb, var(--accent) 55%, transparent); }
.pt-sees-origin { border-color: color-mix(in srgb, var(--allow) 55%, transparent); }

.pt-sees-list { margin: 0 0 0 20px; font-size: 0.88rem; }
.pt-sees-list li { margin: 5px 0; color: var(--text-muted); }

.pt-step-note { font-size: 0.92rem; color: var(--text-muted); margin-top: 14px; }

/* ---------- the visibility matrix ---------- */

.pt-section-heading { margin-top: 46px; }
.pt-section-lede { color: var(--text-muted); font-size: 0.95rem; }

.pt-matrix, .pt-contrast {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
  margin-top: 16px;
  background: var(--bg-inset);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}
.pt-matrix th, .pt-matrix td,
.pt-contrast th, .pt-contrast td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
.pt-matrix thead th, .pt-contrast thead th {
  font-family: var(--mono);
  color: var(--text-muted);
  font-weight: 400;
  text-transform: uppercase;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
}
.pt-matrix thead .pt-col-proxy { color: var(--accent); }
.pt-matrix tbody th, .pt-contrast tbody th {
  font-family: var(--mono);
  color: var(--text);
  font-weight: 700;
  width: 24%;
  font-size: 0.8rem;
}
.pt-matrix tr:last-child th, .pt-matrix tr:last-child td,
.pt-contrast tr:last-child th, .pt-contrast tr:last-child td { border-bottom: none; }

.pt-cell-value {
  display: block;
  font-family: var(--mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.pt-cell-yes .pt-cell-value { color: var(--accent); }
.pt-cell-no .pt-cell-value { color: var(--allow); }
.pt-cell-claim .pt-cell-value { color: #d9a03f; }
.pt-cell-maybe .pt-cell-value { color: #d9a03f; }
.pt-cell-note { display: block; color: var(--text-muted); font-size: 0.8rem; margin-top: 4px; }

.pt-contrast tbody td { color: var(--text-muted); }
.pt-contrast thead th:nth-child(2) { color: var(--accent); }

/* ---------- implications, caveats, sources ---------- */

.pt-implications {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 14px;
  margin-top: 16px;
}

.pt-implication {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-raised);
  padding: 14px 16px;
}
.pt-implication h4 { font-family: var(--mono); font-size: 0.88rem; margin-bottom: 6px; }
.pt-implication p { font-size: 0.88rem; color: var(--text-muted); }

.pt-caveat {
  border: 1px solid var(--border);
  border-left: 3px solid #d9a03f;
  border-radius: 6px;
  background: var(--bg-raised);
  padding: 14px 18px;
  margin: 14px 0;
}
.pt-caveat h3 { font-size: 0.95rem; margin-bottom: 6px; }
.pt-caveat p { font-size: 0.92rem; color: var(--text-muted); }

.pt-sources { margin: 16px 0 0 22px; font-size: 0.9rem; }
.pt-sources li { margin: 8px 0; }
.pt-source-note { color: var(--text-muted); font-size: 0.88em; }