:root {
  --bg: #0e1518;
  --bg-pane: #131e22;
  --bg-pane-2: #0b1316;
  --edge: #20323a;
  --ink: #c9dde2;
  --ink-dim: #7c969e;
  --accent: #38b0c0;
  --accent-soft: #1d4a52;
  --emit: #8fe3c6;
  --err: #e88a8a;
  --warn: #d9c27a;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
}

body {
  background: var(--bg);
  color: var(--ink);
  font-family: "Iosevka", "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 15px;
}

.app {
  height: 100vh;
  display: flex;
  flex-direction: column;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.7rem 1.1rem;
  background: var(--bg-pane);
  border-bottom: 1px solid var(--edge);
  flex: 0 0 auto;
}

.brand { font-size: 1.25rem; letter-spacing: 0.02em; }

.brand .ver {
  font-size: 0.7rem;
  color: var(--ink-dim);
  vertical-align: super;
  margin-left: 0.2rem;
}

.controls {
  display: flex;
  gap: 0.6rem;
  align-items: center;
  flex-wrap: wrap;
}

select, button {
  font-family: inherit;
  font-size: 0.85rem;
  color: var(--ink);
  background: var(--bg-pane-2);
  border: 1px solid var(--edge);
  border-radius: 6px;
  padding: 0.4rem 0.7rem;
  cursor: pointer;
}

select:hover, button:hover { border-color: var(--accent-soft); }

#run {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: #eaf7f9;
  font-weight: 600;
}
#run:hover { background: #235b65; }

.speed-ctl {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.78rem;
  color: var(--ink-dim);
  background: var(--bg-pane-2);
  border: 1px solid var(--edge);
  border-radius: 6px;
  padding: 0.25rem 0.55rem;
}
.speed-ctl #speedVal { min-width: 2.1rem; text-align: right; color: var(--ink); }
.speed-ctl input[type="range"] { width: 6rem; accent-color: var(--accent); }

.mini {
  font-size: 0.7rem;
  padding: 0.15rem 0.5rem;
}

.panes {
  flex: 1 1 auto;
  display: grid;
  grid-template-columns: 0.85fr 1.6fr;
  gap: 1px;
  background: var(--edge);
  min-height: 0;
}

.pane {
  display: flex;
  flex-direction: column;
  background: var(--bg-pane);
  min-height: 0;
  min-width: 0;
}

.pane-label {
  flex: 0 0 auto;
  padding: 0.45rem 0.9rem;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-dim);
  background: var(--bg-pane-2);
  border-bottom: 1px solid var(--edge);
}

#code {
  flex: 1 1 auto;
  resize: none;
  border: 0;
  outline: none;
  background: var(--bg-pane);
  color: var(--ink);
  font-family: inherit;
  font-size: 0.95rem;
  line-height: 1.55;
  padding: 0.9rem 1.1rem;
  tab-size: 2;
}

/* ── flow canvas ── */
.flow-wrap {
  flex: 1 1 auto;
  position: relative;
  min-height: 0;
  min-width: 0;
  overflow: hidden;
}

#flow {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

.progress-track {
  position: absolute;
  left: 0; right: 0; top: 0;
  height: 3px;
  background: rgba(255,255,255,0.04);
  pointer-events: none;
}
.progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--emit));
  transition: width 0.12s linear;
  opacity: 0.35;
}
.progress-track.active .progress-bar { opacity: 1; }

.spill-log {
  position: absolute;
  left: 0.7rem;
  bottom: 0.7rem;
  width: min(38%, 22rem);
  max-height: 42%;
  display: flex;
  flex-direction: column;
  background: rgba(8, 18, 24, 0.78);
  border: 1px solid var(--edge);
  border-radius: 8px;
  backdrop-filter: blur(3px);
  overflow: hidden;
}
.spill-head {
  flex: 0 0 auto;
  padding: 0.3rem 0.6rem;
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--ink-dim);
  border-bottom: 1px solid var(--edge);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.log {
  flex: 1 1 auto;
  overflow-y: auto;
  padding: 0.4rem 0.6rem;
  line-height: 1.45;
  font-size: 0.82rem;
  white-space: pre-wrap;
  word-break: break-word;
}
.log-line { color: var(--emit); }
.log-spill::before { content: "~ "; color: var(--accent); }
.log-err { color: var(--err); }
.log-note { color: var(--ink-dim); font-style: italic; }

/* ── field guide drawer ── */
.guide {
  position: fixed;
  top: 0; right: 0;
  height: 100vh;
  width: min(24rem, 90vw);
  background: var(--bg-pane);
  border-left: 1px solid var(--edge);
  transform: translateX(100%);
  transition: transform 0.25s ease;
  z-index: 20;
  display: flex;
  flex-direction: column;
  box-shadow: -8px 0 28px rgba(0,0,0,0.4);
}
.guide.open { transform: translateX(0); }
.guide-head {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 0.9rem;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-dim);
  background: var(--bg-pane-2);
  border-bottom: 1px solid var(--edge);
}

.ref {
  flex: 1 1 auto;
  overflow-y: auto;
  padding: 0.6rem 1rem 1.4rem;
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--ink-dim);
}
.ref h4 {
  color: var(--accent);
  margin: 1rem 0 0.3rem;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}
.ref p { margin: 0.3rem 0; }
.ref em { color: var(--ink); font-style: normal; }
.ref strong { color: var(--emit); }
.ref code {
  color: var(--ink);
  background: var(--bg-pane-2);
  padding: 0.05rem 0.3rem;
  border-radius: 4px;
}
.ref pre {
  background: var(--bg-pane-2);
  border: 1px solid var(--edge);
  border-radius: 6px;
  padding: 0.5rem 0.7rem;
  margin: 0.3rem 0;
  color: var(--ink);
  white-space: pre-wrap;
}

@media (max-width: 880px) {
  .panes { grid-template-columns: 1fr; grid-template-rows: 0.8fr 1.2fr; }
  .spill-log { width: min(60%, 18rem); }
}