:root {
  --bg: #0d1117;
  --panel: #161b22;
  --panel-2: #1c2330;
  --border: #2b3444;
  --text: #e6edf3;
  --muted: #8b98a9;
  --accent: #58a6ff;
  --master: #f0b429;
  --slave: #3fb950;
  --danger: #f85149;
  --ok: #3fb950;
  --warn: #d29922;
  --env: #a371f7;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

/* ---------- Header ---------- */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 22px;
  background: linear-gradient(90deg, #121a2b, #161b22);
  border-bottom: 1px solid var(--border);
  flex-wrap: nowrap;
  gap: 10px;
}
.title-block { flex: 0 1 auto; min-width: 0; }
.title-block h1 { margin: 0; font-size: 18px; letter-spacing: .3px; white-space: nowrap; }
.title-link {
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px dashed transparent;
  transition: color .15s, border-color .15s;
}
.title-link:hover { color: var(--accent); border-bottom-color: var(--accent); }
.subtitle { margin: 2px 0 0; color: var(--muted); font-size: 11.5px; }
.byline { margin: 2px 0 0; font-size: 11px; color: var(--muted); }
.byline a { color: var(--accent); text-decoration: none; border-bottom: 1px dashed transparent; transition: border-color .15s; }
.byline a:hover { border-bottom-color: var(--accent); }

.sim-controls { display: flex; gap: 8px; flex: 0 0 auto; align-items: center; }

/* Step-mode control: checkbox + step-size box, sits inline with the buttons */
.sim-step {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--panel-2);
  font-size: 11.5px;
  color: var(--muted);
  white-space: nowrap;
}
.sim-step input[type="number"] {
  width: 52px;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 2px 4px;
  font-size: 11px;
}
.sim-step .unit { color: var(--muted); }

.btn {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 9px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  transition: .15s;
}
.btn:hover:not(:disabled) { border-color: var(--accent); background: #222c3d; }
.btn:disabled { opacity: .4; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: #06101f; border-color: var(--accent); }
.btn-primary:hover:not(:disabled) { background: #79b8ff; }
.btn-ghost { background: transparent; }

/* ---------- Layout ---------- */
.layout {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 16px;
}
/* Config sidebar (left) + workspace (right). */
.main-row {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 16px;
  align-items: start;
}
.main-row.config-hidden { grid-template-columns: 1fr; }
.main-row.config-hidden .config-panel { display: none; }
.config-panel { position: sticky; top: 16px; }
.config-grid { display: block; }
.config-grid fieldset { margin-bottom: 14px; }
/* Workspace: stage full width (log is a top horizontal strip). */
.workspace {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  align-items: start;
  min-width: 0;            /* allow the grid track to shrink below content width */
}
.layout.log-hidden .log-embed { display: none; }
#btnToggleConfig.active { background: var(--accent); color: #06101f; border-color: var(--accent); }

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}
.panel h2 { margin: 0 0 12px; font-size: 15px; }

/* ---------- Config ---------- */
fieldset {
  border: 1px solid var(--border);
  border-radius: 10px;
  margin: 0 0 14px;
  padding: 10px 12px 14px;
}
legend { color: var(--accent); font-size: 12.5px; font-weight: 700; padding: 0 6px; }
.config-panel label {
  display: block;
  font-size: 12.5px;
  color: var(--muted);
  margin-top: 10px;
}
.config-panel label:first-of-type { margin-top: 2px; }
.unit { color: #5f6b7c; font-size: 11px; }
.config-panel input[type="number"],
.config-panel input[type="range"] {
  width: 100%;
  margin-top: 4px;
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 13px;
}
.config-panel input[type="range"] { padding: 0; }
output { font-size: 12px; color: var(--text); }
label.chk {
  display: flex !important;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  color: var(--text) !important;
  margin-top: 12px !important;
}
label.chk input[type="checkbox"] { width: auto; margin: 0; accent-color: var(--accent); }
.ppm-out {
  display: block;
  margin-top: 3px;
  font-family: "Consolas", monospace;
  font-size: 11px;
  color: var(--accent);
}
.legend-note { color: #5f6b7c; font-style: italic; }

/* ---------- Top band: combined sync panel (full width) ---------- */
.top-band {
  display: flex;
  align-items: stretch;
  gap: 16px;
}
.top-band .sync-panel { flex: 1 1 auto; }

/* ---------- Timestamp chart row: chart + slave calc + status tiles column ---------- */
.timer-row {
  display: flex;
  align-items: stretch;
  flex-wrap: wrap;
  gap: 16px;
  min-width: 0;
}
.timer-row .graph-panel { flex: 3 1 440px; min-width: 0; }
.timer-row .calc-panel-side { flex: 1 1 300px; min-width: 0; overflow-y: auto; }

/* ---------- Simulation config (header, centered) ---------- */
.sim-inline {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: rgba(13, 20, 32, 0.5);
  flex: 1 1 auto;
  min-width: 0;
  justify-content: center;
}
.sim-title {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .5px;
  color: var(--accent);
  padding-right: 6px;
}
.sim-field {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--panel-2);
  border: 1px solid var(--border);
}
.sim-lbl {
  display: flex;
  align-items: baseline;
  gap: 4px;
  font-size: 10px;
  font-weight: 600;
  color: var(--text);
}
.sim-inline .unit { font-size: 8.5px; font-weight: 400; color: var(--muted); }
.sim-inline output { font-size: 10px; font-weight: 700; color: var(--accent); font-family: "Consolas", monospace; }
.sim-inline input[type="number"] {
  width: 70px;
  max-width: 100%;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 2px 6px;
  font-size: 11px;
}
.sim-inline input[type="range"] { width: 96px; max-width: 100%; vertical-align: middle; margin: 2px 0; }
.sim-inline select#cfgStepMode,
.sim-inline select#cfgTsMode {
  width: auto;
  min-width: 66px;
  max-width: 100%;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 2px 6px;
  font-size: 11px;
  font-family: inherit;
}
/* Checkbox chip (Pdelay enable) */
.sim-chk { justify-content: center; }
.sim-chk .sim-lbl { justify-content: center; }
.sim-inline input[type="checkbox"] {
  width: 15px;
  height: 15px;
  accent-color: var(--accent);
  cursor: pointer;
  align-self: center;
  margin: 1px 0;
}

/* ---------- Stage ---------- */
.stage { display: flex; flex-direction: column; gap: 16px; min-width: 0; }

/* Combined sync panel: master | link + results | slave */
.sync-panel { padding: 12px 14px; }
.sync-panel h2 { display: flex; align-items: baseline; gap: 8px; flex-wrap: wrap; margin: 0 0 10px; font-size: 14px; }
.sync-grid {
  display: grid;
  grid-template-columns: minmax(220px, 0.85fr) minmax(380px, 1.7fr) minmax(220px, 0.85fr);
  gap: 12px;
  align-items: start;
}
.sync-col { display: flex; flex-direction: column; gap: 8px; }
.sync-col .node { flex: 0 0 auto; }
.ts-group {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 9px;
}
.ts-group h4 { margin: 0 0 3px; font-size: 11px; color: var(--accent); }
.sync-master .ts-group h4 { color: var(--master); }
.sync-slave .ts-group h4 { color: var(--slave); }

/* compact timestamp key beneath the master / slave node cards */
.ts-key {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 9px;
}
.ts-key h5 { margin: 0 0 4px; font-size: 10.5px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
.sync-master .ts-key h5 { color: var(--master); }
.sync-slave .ts-key h5 { color: var(--slave); }
.ts-key-row { display: flex; gap: 6px; align-items: baseline; font-size: 10.5px; line-height: 1.5; }
.ts-key-row .sym { flex: 0 0 18px; font-family: Consolas, monospace; font-weight: 700; }
.ts-key-row span:last-child { color: var(--muted); }
.sync-link .calc { display: block; }
.calc-block {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 9px;
}
.calc-block h4 {
  margin: 0 0 4px;
  font-size: 12px;
  color: var(--accent);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.calc-block h4 .at { font-size: 10px; font-weight: 400; color: var(--muted); }
/* combined "Slave calculation" window */
.calc-sub {
  margin: 6px 0 3px;
  font-size: 11px;
  font-weight: 600;
  color: var(--muted);
  display: flex;
  gap: 6px;
  align-items: baseline;
}
.calc-sub:first-of-type { margin-top: 2px; }
.calc-sub .at { font-size: 10px; font-weight: 400; color: var(--muted); }
/* formula, value list, then simplified formula + result + comments.
   All three areas share one font size for a uniform, uncluttered look. */
.calc-line { margin-bottom: 12px; }
.calc-line .formula,
.calc-line .calc-vals,
.calc-line .result,
.calc-line .result * {
  font-family: "Consolas", monospace;
  font-size: 11.5px;
  line-height: 1.6;
  font-weight: 400;
}
.calc-line .formula { margin: 0 0 4px; }
/* Values listed one per line: t₁ = …, t₂ = … */
.calc-line .calc-vals {
  margin: 0 0 4px;
  padding-left: 10px;
  color: var(--muted);
  word-break: break-word;
}
.calc-line .calc-vals > div { white-space: nowrap; }
/* Result block: simplified formula → final result → comments */
.calc-line .result { margin: 0; padding-left: 10px; color: var(--text); }
.calc-line .result .calc-simplified { color: #9db3d0; }
.calc-line .result .calc-final { margin-top: 2px; }
.calc-line .result .calc-comment { margin-top: 2px; color: var(--muted); }
/* Grayed-out step when the peer-delay (Pdelay) mechanism is disabled */
.calc-disabled { opacity: 0.4; }
.calc-disabled .formula,
.calc-disabled .calc-vals,
.calc-disabled .result { filter: grayscale(1); }
.calc-row {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  font-size: 11px;
  color: var(--muted);
  padding: 1px 0;
}
.calc-row .val { font-family: "Consolas", monospace; color: var(--text); }

/* Compact overrides inside the combined sync panel */
.node-row { display: flex; gap: 8px; align-items: stretch; }
.node-row .node { flex: 1 1 0; }
.node-row .ts-key { flex: 1 1 0; align-self: stretch; }
.sync-col .node { padding: 10px 12px; }
.sync-col .node-icon { font-size: 24px; line-height: 1; }
.sync-col .node-name { font-size: 13px; margin-top: 2px; }
.sync-col .node-clock { font-size: 17px; margin-top: 4px; }
.sync-col .node-raw { font-size: 11px; }
.sync-col .node-tag { margin-top: 6px; padding: 2px 8px; font-size: 10px; }
.sync-col .stbm-box { margin-top: 6px; padding: 6px 8px; }
.sync-col .stbm-row { font-size: 10.5px; }
.sync-panel table.ts { font-size: 11px; }
.sync-panel table.ts td { padding: 2px 3px; }
.sync-panel table.ts .who { font-size: 9.5px; }
.sync-panel .formula { margin-top: 6px; padding: 5px 7px; font-size: 11px; }
.sync-panel .result { margin-top: 5px; font-size: 11px; }
.sync-panel .result.sub { font-size: 10px; }
.sync-panel .verdict { margin-top: 5px; padding: 4px 8px; font-size: 11px; }

/* Network */
.network-panel {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
}
.node {
  text-align: center;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
  background: radial-gradient(circle at 50% 0%, #1d2637, #141a24);
  transition: box-shadow .2s;
  position: relative;
}
.node-master { box-shadow: 0 0 0 1px rgba(240,180,41,.25); }
.node-slave  { box-shadow: 0 0 0 1px rgba(63,185,80,.25); }
.node.flash-master { box-shadow: 0 0 24px 2px rgba(240,180,41,.7); }
.node.flash-slave  { box-shadow: 0 0 24px 2px rgba(63,185,80,.7); }
.node.flash-reject { box-shadow: 0 0 24px 2px rgba(248,81,73,.75); }
.node-icon { font-size: 34px; }
.node-name { font-weight: 700; margin-top: 4px; }
.node-clock {
  font-family: "Consolas", monospace;
  font-size: 22px;
  margin-top: 8px;
  letter-spacing: 1px;
}
.node-master .node-clock { color: var(--master); }
.node-slave  .node-clock { color: var(--slave); }
.node-raw { font-family: "Consolas", monospace; font-size: 12px; color: var(--muted); margin-top: 2px; }
.stbm-box {
  margin-top: 10px;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #0d1420;
  text-align: left;
}
.stbm-row {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  font-size: 11px;
  color: var(--muted);
  padding: 1px 0;
}
.stbm-row .mono { font-family: "Consolas", monospace; color: var(--slave); }
.stbm-row .mono.warn { color: var(--warn); }
.stbm-row .mono.bad { color: var(--danger); font-weight: 600; }
.node-tag {
  display: inline-block;
  margin-top: 10px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .5px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--muted);
}
#slaveState.state-unsync { color: var(--danger); border-color: var(--danger); }
#slaveState.state-sync   { color: var(--ok); border-color: var(--ok); }
#slaveState.state-holdover { color: var(--warn); border-color: var(--warn); }

/* state tag placed inline next to the "Slave" name */
.node-name-row { display: inline-flex; align-items: baseline; gap: 8px; }
.node-tag-inline { margin-top: 0 !important; padding: 2px 8px; font-size: 9.5px; letter-spacing: .4px; }

.link { position: relative; text-align: center; }
.link-label { color: var(--muted); font-size: 11px; margin-top: 2px; }
.frame-legend {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 4px 10px;
  margin-top: 6px;
  font-size: 10px;
  color: var(--muted);
}
.frame-legend span { display: inline-flex; align-items: center; gap: 4px; }
.fr { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }
.fr-sync   { background: #58a6ff; }
.fr-fup    { background: #79c0ff; }
.fr-preq   { background: #f0b429; }
.fr-presp  { background: #3fb950; }
.fr-prfup  { background: #56d4b8; }

/* Alerts strip */
.alerts { display: flex; flex-wrap: wrap; gap: 8px; }
.alerts:empty { display: none; }
.alert {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid;
}
.alert.ok   { color: var(--ok);     border-color: rgba(63,185,80,.5);  background: rgba(63,185,80,.08); }
.alert.warn { color: var(--warn);   border-color: rgba(210,153,34,.5); background: rgba(210,153,34,.1); }
.alert.bad  { color: var(--danger); border-color: rgba(248,81,73,.5);  background: rgba(248,81,73,.12); }

/* gPTP computation panel */
.compute-panel h2 { display: flex; align-items: baseline; gap: 8px; }
.hint { font-size: 11px; font-weight: 400; color: var(--muted); }
.compute-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.compute-col {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 14px;
}
.compute-col h3 {
  margin: 0 0 8px;
  font-size: 13px;
  color: var(--accent);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.compute-col h3 .at { font-size: 11px; font-weight: 400; color: var(--muted); }
table.ts { width: 100%; border-collapse: collapse; font-size: 12px; }
table.ts td { padding: 3px 4px; border-bottom: 1px solid rgba(43,52,68,.5); }
table.ts .sym {
  font-family: "Consolas", monospace;
  color: var(--master);
  font-weight: 700;
  width: 22px;
}
/* Color-coded timestamp symbols to disambiguate reused t₁/t₂ across message types.
   Same classes are applied to the symbols inside the formulas. */
table.ts .sym.t-pd, .t-pd  { color: #58a6ff; font-weight: 700; }   /* Pdelay handshake t₁–t₄ */
table.ts .sym.t-sy, .t-sy  { color: #a371f7; font-weight: 700; }   /* Sync t₁ / t₂ */
table.ts .sym.t-mpd, .t-mpd { color: #3fb950; font-weight: 700; }  /* δ meanPathDelay */
table.ts .sym.t-c, .t-c   { color: #d29922; font-weight: 700; }    /* correctionField c */
table.ts .sym.t-dp, .t-dp  { color: #f85149; font-weight: 700; }   /* poll notify delay Δp */
table.ts .desc { color: var(--muted); }
table.ts .who { color: #5f6b7c; font-size: 10.5px; }
table.ts .val {
  text-align: right;
  font-family: "Consolas", monospace;
  color: var(--text);
  white-space: nowrap;
}
.formula {
  margin-top: 10px;
  font-family: "Consolas", monospace;
  font-size: 12px;
  color: #9db3d0;
  background: #0b0f16;
  border: 1px dashed var(--border);
  border-radius: 6px;
  padding: 7px 9px;
}
.result {
  margin-top: 8px;
  font-family: "Consolas", monospace;
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
}
.result.sub { font-size: 12.5px; font-weight: 600; color: var(--muted); }
.result .ok { color: var(--ok); }
.result .warn { color: var(--warn); }
.result .bad { color: var(--danger); }
.verdict {
  margin-top: 8px;
  font-size: 12px;
  font-weight: 700;
  padding: 6px 10px;
  border-radius: 6px;
  text-align: center;
}
.verdict.apply { color: var(--ok); background: rgba(63,185,80,.12); border: 1px solid rgba(63,185,80,.4); }
.verdict.init  { color: var(--accent); background: rgba(88,166,255,.12); border: 1px solid rgba(88,166,255,.4); }
.verdict.reject{ color: var(--danger); background: rgba(248,81,73,.14); border: 1px solid rgba(248,81,73,.5); }

@media (max-width: 720px) {
  .compute-grid { grid-template-columns: 1fr; }
  .sync-grid { grid-template-columns: 1fr; }
}

/* Tiles */
.tiles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 12px;
}
/* Single column × 5 rows next to the timestamp chart */
.tiles-col {
  flex: 0 0 210px;
  align-self: stretch;
  grid-template-columns: 1fr;
  grid-auto-rows: 1fr;
}
.tile {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.tile-label { font-size: 11.5px; color: var(--muted); }
.tile-value { font-size: 20px; font-weight: 700; font-family: "Consolas", monospace; }
.tile-sub { font-size: 11px; color: var(--muted); }
.tile-value.ok { color: var(--ok); }
.tile-value.bad { color: var(--danger); }
.tile-value.warn { color: var(--warn); }

/* Slave calculation panel, docked beside the timestamp chart */
.calc-panel-side { padding: 12px 14px; }
.calc-panel-side .calc-block { border: none; background: transparent; padding: 0; }
.calc-panel-side .calc-block h4 { font-size: 13px; margin-bottom: 6px; }

/* Graph */
.graph-header { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px; }
.zoom-bar { display: flex; align-items: center; gap: 6px; }
.zoom-label { font-size: 11.5px; color: var(--muted); }
.btn-mini {
  padding: 4px 9px;
  font-size: 12px;
  border-radius: 6px;
}
.zoom-out {
  font-family: "Consolas", monospace;
  font-size: 12.5px;
  color: var(--text);
  min-width: 58px;
  text-align: center;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 6px;
}
.legend { display: flex; gap: 14px; flex-wrap: wrap; font-size: 11.5px; color: var(--muted); }
.legend span { display: inline-flex; align-items: center; gap: 5px; }
.sw { width: 12px; height: 12px; border-radius: 3px; display: inline-block; }
.sw-dev { background: var(--slave); }
.sw-acc { background: rgba(88,166,255,.35); }
.sw-env { background: var(--env); }
.sw-ok  { background: var(--ok); border-radius: 50%; }
.sw-rej { background: var(--danger); border-radius: 50%; }
.sw-master { background: var(--master); }
.sw-slave  { background: var(--slave); }
.sw-rx { background: repeating-linear-gradient(90deg, #58a6ff 0 4px, transparent 4px 7px); }
#graphCanvas { width: 100%; height: auto; display: block; border-radius: 8px; background: #0b0f16; }
#clockCanvas { width: 100%; height: auto; display: block; border-radius: 8px; background: #0b0f16; }
#timerCanvas { width: 100%; height: auto; display: block; border-radius: 8px; background: #0b0f16; }
#linkCanvas { width: 100%; height: auto; display: block; border-radius: 8px; background: #0b0f16; }

/* Log */
.log-panel { padding: 5px 10px; }
.log-panel .log-head { display: flex; align-items: center; margin-bottom: 4px; }
.log-panel .log-head h2 { margin: 0; }

/* Event log embedded inside the timestamp chart panel */
.log-embed {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
  min-width: 0;
}
.log-embed .log-head { display: flex; align-items: center; margin-bottom: 6px; }
.log-embed .log-head h2 { margin: 0; font-size: 14px; }

/* Horizontal, compact, color-coded log strip. Newest entry on the left. */
.log-strip {
  display: flex;
  flex-direction: row-reverse;
  justify-content: flex-start;
  flex-wrap: nowrap;
  gap: 6px;
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  overflow-y: hidden;
  padding-bottom: 4px;
  align-items: stretch;
}
.log-strip .log-line {
  flex: 0 0 auto;
  width: 20px;
  height: 105px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  font-family: "Consolas", monospace;
  font-size: 11px;
  line-height: 1.1;
  padding: 5px 5px;
  border: 1px solid var(--border);
  border-bottom-width: 3px;
  border-radius: 5px;
  background: var(--panel-2);
  overflow: hidden;
}
.log-strip .log-line.lvl-ok { border-bottom-color: var(--ok); }
.log-strip .log-line.lvl-rej { border-bottom-color: var(--danger); }
.log-strip .log-line.lvl-warn { border-bottom-color: var(--warn); }
.log-strip .log-line.lvl-info { border-bottom-color: var(--muted); }
/* Timestamp sits above the event tag, at a 45° angle */
.log-strip .log-time {
  flex: 0 0 auto;
  height: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: var(--muted);
  writing-mode: horizontal-tb;
  transform: rotate(-90deg);
  transform-origin: center;
  white-space: nowrap;
  padding: 0px 20px 0 0;
}
/* Short tag runs vertically, reading bottom-to-top */
.log-strip .log-tag {
  flex: 1 1 auto;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-weight: 700;
  letter-spacing: .5px;
}
.log-time { color: var(--accent); }
.log-ok { color: var(--ok); }
.log-rej { color: var(--danger); }
.log-info { color: var(--muted); }
.log-warn { color: var(--warn); }
.log-panel { position: static; }

@media (max-width: 900px) {
  .main-row { grid-template-columns: 1fr; }
  .config-panel { position: static; }
}

/* Header: on narrow screens let the three sections stack instead of being
   crammed into one non-wrapping row (which pushed the title off-alignment). */
@media (max-width: 820px) {
  .app-header {
    flex-wrap: wrap;
    justify-content: center;
    text-align: center;
    padding: 10px 14px;
    gap: 8px;
  }
  .title-block {
    flex: 1 1 100%;
    text-align: center;
  }
  .title-block h1 { white-space: normal; font-size: 16px; }
  .subtitle { font-size: 11px; }
  .sim-inline {
    flex: 1 1 100%;
    order: 3;
  }
  .sim-controls {
    flex: 1 1 100%;
    order: 2;
    justify-content: center;
    flex-wrap: wrap;
  }
}

/* ---------------- Footer / creator credit ---------------- */
.app-footer {
  margin-top: 28px;
  border-top: 1px solid var(--border);
  background: var(--panel);
}
.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.footer-credit { display: flex; flex-direction: column; gap: 2px; }
.footer-by { font-size: 13.5px; color: var(--text); }
.footer-by strong { color: var(--accent); }
.footer-role { font-size: 12px; color: var(--muted); }
.footer-links { display: flex; gap: 16px; flex-wrap: wrap; }
.footer-links a {
  color: var(--accent);
  text-decoration: none;
  font-size: 13px;
  border-bottom: 1px solid transparent;
  transition: border-color .15s;
}
.footer-links a:hover { border-bottom-color: var(--accent); }
@media (max-width: 720px) {
  .footer-inner { flex-direction: column; align-items: flex-start; }
}
.footer-meta {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px 10px;
  align-items: center;
  font-size: 11.5px;
  color: var(--muted);
}
.footer-meta .footer-dot { color: var(--border); }

/* ---------------- Feedback & community ---------------- */
.feedback {
  max-width: 1100px;
  margin: 36px auto 0;
  padding: 24px;
  border-top: 1px solid var(--border);
}
.feedback-title { font-size: 20px; margin: 0 0 8px; color: var(--text); }
.feedback-intro { color: var(--muted); font-size: 14px; margin: 0 0 18px; max-width: 72ch; }
.feedback-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 26px; }
.fb-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  transition: border-color .15s, background .15s, transform .1s;
}
.fb-btn:hover { transform: translateY(-1px); background: var(--panel-2); }
.fb-discuss:hover { border-color: var(--accent); }
.fb-issue:hover { border-color: var(--warn); }
.fb-star:hover { border-color: var(--slave); }
.feedback-sub { font-size: 15px; margin: 4px 0 10px; color: var(--text); }
.feedback-hint { font-size: 12px; font-weight: 400; color: var(--muted); }
/* Keep the Cusdis comment box a comfortable reading width and let its iframe
   grow to fit its content so it doesn't show an internal scrollbar. */
#cusdis_thread { margin-top: 8px; min-height: 330px; }
#cusdis_thread iframe { width: 100% !important; min-height: 330px; }