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

/* Keep the hidden attribute authoritative over display:flex/grid component rules */
[hidden] { display: none !important; }

:root {
  --bg: #05040c;
  --panel: #0d0c1d;
  --panel-deep: #070712;
  --border: rgba(103, 232, 249, 0.14);
  --border-soft: rgba(136, 146, 164, 0.18);
  --cyan: #67e8f9;
  --cyan-dim: rgba(103, 232, 249, 0.12);
  --violet: #8b68d4;
  --violet-light: #a884f0;
  --violet-dim: rgba(139, 104, 212, 0.14);
  --amber: #fbbf24;
  --amber-dim: rgba(251, 191, 36, 0.14);
  --red: #fb7185;
  --red-dim: rgba(251, 113, 133, 0.14);
  --green: #4ade80;
  --green-dim: rgba(74, 222, 128, 0.14);
  --text: #e2e8f0;
  --muted: #8892a4;
  --mono: 'Fira Code', 'JetBrains Mono', 'Courier New', monospace;
}

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.6;
}

.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;
}

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

main {
  max-width: 1040px;
  margin: 0 auto;
  padding: 2.5rem 2rem 4rem;
}

/* BACK LINK */
.back {
  display: inline-flex;
  margin-bottom: 1.5rem;
  color: var(--cyan);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
}

.back::before { content: '← '; margin-right: 0.35rem; }
.back:hover { text-decoration: underline; }

/* HERO */
.hero { margin-bottom: 2.5rem; }

.eyebrow {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 0.6rem;
}

.hero h1 {
  font-size: 2.2rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  background: linear-gradient(100deg, var(--text) 40%, var(--violet-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.dek {
  color: var(--muted);
  font-size: 1rem;
  max-width: 46rem;
  margin-bottom: 1.5rem;
}

.hero-facts {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.fact {
  border-left: 2px solid var(--cyan);
  padding-left: 0.9rem;
  font-size: 0.88rem;
  color: var(--muted);
  max-width: 22rem;
}

.fact strong { color: var(--text); display: block; }

/* EXPLAINER / DETAILS */
.explainer, .callout {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0;
  overflow: hidden;
}

.explainer { max-width: 46rem; }

.explainer summary, .callout summary {
  cursor: pointer;
  padding: 0.9rem 1.25rem;
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--cyan);
  list-style-position: inside;
  transition: background 0.2s;
}

.explainer summary:hover, .callout summary:hover { background: var(--cyan-dim); }

.explainer p, .callout p {
  padding: 0 1.25rem 1.1rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.explainer p strong, .callout p strong { color: var(--text); }
.callout code, .explainer code { font-family: var(--mono); font-size: 0.82em; color: var(--violet-light); }

/* ERROR BANNER */
.crypto-error {
  background: var(--red-dim);
  border: 1px solid var(--red);
  border-radius: 10px;
  color: var(--red);
  padding: 1rem 1.25rem;
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}

.crypto-error code { font-family: var(--mono); }

/* PANELS */
.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem 1.75rem;
  margin-bottom: 1.5rem;
}

.panel-title {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--violet-light);
  margin-bottom: 1rem;
}

/* CONTROLS */
.control-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.control-row + .control-row { margin-top: 1rem; }

.mode-toggle {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.mode-btn {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--muted);
  background: none;
  border: none;
  padding: 0.45rem 1.1rem;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.mode-btn.is-active {
  background: var(--cyan-dim);
  color: var(--cyan);
}

.mode-btn:disabled { opacity: 0.45; cursor: default; }

.count-label {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--muted);
}

.count-label select {
  font-family: inherit;
  font-size: 0.85rem;
  background: var(--panel-deep);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.4rem 0.6rem;
  cursor: pointer;
}

.count-label select:disabled { opacity: 0.45; cursor: default; }

.eve-toggle {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  background: none;
  border: 1px solid var(--border-soft);
  color: var(--muted);
  border-radius: 999px;
  padding: 0.45rem 1.1rem;
  cursor: pointer;
  transition: all 0.2s;
}

.eve-toggle:hover:not(:disabled) { border-color: var(--red); color: var(--text); }

.eve-toggle.eve-on {
  background: var(--red-dim);
  border-color: var(--red);
  color: var(--red);
}

.eve-toggle:disabled { opacity: 0.45; cursor: default; }

.btn {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.5rem 1.4rem;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: opacity 0.2s, border-color 0.2s, color 0.2s;
}

.btn-run { background: var(--violet); color: #fff; }
.btn-run:hover:not(:disabled) { opacity: 0.85; }

.btn-step {
  background: none;
  border: 1px solid var(--cyan);
  color: var(--cyan);
}

.btn-step:hover:not(:disabled) { background: var(--cyan-dim); }

.btn-reset {
  background: none;
  border: 1px solid var(--border-soft);
  color: var(--muted);
}

.btn-reset:hover:not(:disabled) { border-color: var(--text); color: var(--text); }

.btn:disabled { opacity: 0.4; cursor: default; }

/* QUANTUM CHANNEL */
.channel {
  display: flex;
  align-items: stretch;
  gap: 1rem;
  min-height: 130px;
}

.lane {
  flex: 0 0 auto;
  width: 130px;
  background: var(--panel-deep);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.75rem;
  text-align: center;
}

.lane-avatar { font-size: 1.6rem; line-height: 1.3; }

.lane-name {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.4rem;
}

.lane-alice .lane-name { color: var(--violet-light); }
.lane-bob .lane-name { color: var(--green); }

.lane-readout {
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 0.1rem 0.3rem;
}

.ro-label { color: var(--muted); }
.ro-val { color: var(--text); font-weight: 600; }

.channel-track {
  position: relative;
  flex: 1;
  min-width: 120px;
}

.channel-track::before {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  background: linear-gradient(90deg,
    rgba(103, 232, 249, 0.08),
    rgba(103, 232, 249, 0.4),
    rgba(103, 232, 249, 0.08));
  background-size: 200% 100%;
}

.channel.wire-active .channel-track::before {
  animation: wireflow 1.4s linear infinite;
}

@keyframes wireflow {
  from { background-position: 200% 0; }
  to   { background-position: 0% 0; }
}

.photon {
  position: absolute;
  left: 0%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.05rem;
  font-weight: 700;
  z-index: 2;
  transition-property: left;
  transition-timing-function: linear;
}

.photon[hidden] { display: none; }

.photon-rect {
  color: var(--amber);
  background: var(--amber-dim);
  border: 1px solid var(--amber);
  box-shadow: 0 0 14px rgba(251, 191, 36, 0.4);
}

.photon-diag {
  color: var(--cyan);
  background: var(--cyan-dim);
  border: 1px solid var(--cyan);
  box-shadow: 0 0 14px rgba(103, 232, 249, 0.4);
}

.photon-intercepted {
  box-shadow: 0 0 16px rgba(251, 113, 133, 0.65);
}

.eve-node {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 118px;
  background: var(--panel-deep);
  border: 1px solid var(--red);
  border-radius: 10px;
  padding: 0.5rem;
  text-align: center;
  z-index: 3;
  display: none;
  transition: box-shadow 0.25s;
}

.channel.has-eve .eve-node { display: block; }
.eve-node .lane-name { color: var(--red); }
.eve-node .lane-avatar { font-size: 1.3rem; }

.eve-node.eve-flash { box-shadow: 0 0 22px rgba(251, 113, 133, 0.7); }

.channel-status {
  margin-top: 1rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--cyan);
  min-height: 1.4em;
}

.channel-legend {
  margin-top: 0.4rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
}

.b-rect { color: var(--amber); font-weight: 600; }
.b-diag { color: var(--cyan); font-weight: 600; }

/* PROTOCOL LOG (terminal) */
.log-panel { padding: 0; background: none; border: none; }

.terminal {
  background: var(--panel-deep);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.5rem;
  font-family: var(--mono);
  font-size: 0.82rem;
}

.terminal-bar {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 1rem;
}

.terminal-dot { width: 12px; height: 12px; border-radius: 50%; }
.dot-red    { background: #ff5f57; }
.dot-yellow { background: #febc2e; }
.dot-green  { background: #28c840; }

.terminal-title {
  margin-left: 0.6rem;
  font-size: 0.72rem;
  color: var(--muted);
  letter-spacing: 0.06em;
}

.table-scroll {
  overflow-x: auto;
  overflow-y: auto;
  max-height: 340px;
  -webkit-overflow-scrolling: touch;
}

.protocol-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  text-align: center;
}

.protocol-table th {
  position: sticky;
  top: 0;
  background: var(--panel-deep);
  color: var(--muted);
  font-weight: 600;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.4rem 0.6rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
  z-index: 1;
}

.protocol-table td {
  padding: 0.3rem 0.6rem;
  border-bottom: 1px solid rgba(103, 232, 249, 0.05);
  color: var(--text);
  white-space: nowrap;
}

.protocol-table .col-eve { display: none; }
.protocol-table.has-eve .col-eve { display: table-cell; }

.row-discarded td { opacity: 0.38; }
.row-sacrificed td { background: var(--violet-dim); }
.row-error td { background: var(--red-dim); }

.sift-yes { color: var(--green); font-weight: 700; }
.sift-no { color: var(--muted); }
.cell-eve { color: var(--red); }

.log-empty {
  text-align: center;
  color: var(--muted);
  padding: 1.5rem 0;
  font-size: 0.8rem;
}

.log-key {
  display: flex;
  gap: 1.25rem;
  flex-wrap: wrap;
  margin-top: 0.9rem;
  font-size: 0.72rem;
  color: var(--muted);
}

.lk-item { display: inline-flex; align-items: center; gap: 0.4rem; }

.swatch {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  display: inline-block;
}

.swatch-sacrificed { background: var(--violet-dim); border: 1px solid var(--violet); }
.swatch-error { background: var(--red-dim); border: 1px solid var(--red); }
.swatch-discarded { background: rgba(136, 146, 164, 0.15); border: 1px solid var(--border-soft); }

/* STATS */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.stat-tile {
  background: var(--panel-deep);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.9rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.stat-label {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--muted);
}

.stat-hint { cursor: help; opacity: 0.7; text-transform: none; }

.stat-tile strong {
  font-size: 1.35rem;
  font-weight: 700;
  font-family: var(--mono);
}

.stat-sub { font-size: 0.68rem; color: var(--muted); }

.verdict-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.verdict-badge {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 0.4rem 1rem;
  border-radius: 999px;
}

.verdict-pending { background: rgba(136, 146, 164, 0.12); color: var(--muted); border: 1px solid var(--border-soft); }
.verdict-clean { background: var(--green-dim); color: var(--green); border: 1px solid var(--green); }
.verdict-compromised { background: var(--red-dim); color: var(--red); border: 1px solid var(--red); }

.qber-caveat { font-size: 0.78rem; color: var(--amber); }

.key-preview {
  margin-top: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.key-preview code {
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--green);
  background: var(--panel-deep);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.7rem 0.9rem;
  word-break: break-all;
  line-height: 1.8;
}

/* OTP PANEL */
.otp-intro {
  color: var(--muted);
  font-size: 0.88rem;
  max-width: 42rem;
  margin-bottom: 1rem;
}

.otp-row { display: flex; gap: 0.75rem; flex-wrap: wrap; }

.otp-row input {
  flex: 1;
  min-width: 220px;
  font-family: var(--mono);
  font-size: 0.85rem;
  background: var(--panel-deep);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.55rem 0.8rem;
}

.otp-row input:disabled { opacity: 0.45; }
.otp-row input::placeholder { color: var(--muted); }

.otp-warn {
  margin-top: 0.9rem;
  font-size: 0.82rem;
  color: var(--amber);
}

.otp-output { margin-top: 1.1rem; display: flex; flex-direction: column; gap: 0.75rem; align-items: flex-start; }

.otp-line {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  width: 100%;
}

.otp-line .ro-label { flex: 0 0 auto; width: 7.5ch; }

.otp-line code {
  font-family: var(--mono);
  color: var(--cyan);
  word-break: break-all;
}

#otpPlain { color: var(--green); }

/* EXPLAINER GRID */
.explainers { margin-top: 2.5rem; }

.explainer-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  align-items: start;
}

/* FOOTER */
footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 0.45rem 0.75rem;
  text-align: center;
  padding: 2rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}

.clacks-tribute {
  color: inherit;
  font-size: 0.72rem;
  letter-spacing: 0;
  text-transform: uppercase;
  opacity: 0.56;
}

.clacks-tribute::before { content: '// '; opacity: 0.45; }

/* REDUCED MOTION (belt-and-suspenders alongside the JS check) */
@media (prefers-reduced-motion: reduce) {
  .photon { transition: none !important; }
  .channel.wire-active .channel-track::before { animation: none; }
}

html[data-env-motion="reduce"] .photon { transition: none !important; }
html[data-env-motion="reduce"] .channel.wire-active .channel-track::before { animation: none; }

/* RESPONSIVE */
@media (max-width: 900px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .explainer-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 1.8rem; }
  .lane { width: 112px; }
}

@media (max-width: 640px) {
  main { padding: 1.5rem 1rem 3rem; }
  .panel { padding: 1.1rem 1rem; }
  .control-row { gap: 0.6rem; }
  .control-row.actions .btn { flex: 1; text-align: center; }
  .channel { gap: 0.5rem; min-height: 118px; }
  .lane { width: 96px; padding: 0.5rem 0.35rem; }
  .lane-avatar { font-size: 1.25rem; }
  .lane-readout { font-size: 0.7rem; }
  .eve-node { width: 92px; padding: 0.35rem; }
  .eve-node .lane-readout { font-size: 0.66rem; }
  .photon { width: 28px; height: 28px; font-size: 0.85rem; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 0.6rem; }
  .stat-tile strong { font-size: 1.1rem; }
  .terminal { padding: 1rem 0.9rem; }
  .table-scroll { max-height: 280px; }
}